WorldWideScience

Sample records for additive mutational effects

  1. Additive dominant effect of a SOX10 mutation underlies a complex phenotype of PCWH.

    Ito, Yukiko; Inoue, Naoko; Inoue, Yukiko U; Nakamura, Shoko; Matsuda, Yoshiki; Inagaki, Masumi; Ohkubo, Takahiro; Asami, Junko; Terakawa, Youhei W; Kohsaka, Shinichi; Goto, Yu-ichi; Akazawa, Chihiro; Inoue, Takayoshi; Inoue, Ken

    2015-08-01

    Distinct classes of SOX10 mutations result in peripheral demyelinating neuropathy, central dysmyelinating leukodystrophy, Waardenburg syndrome, and Hirschsprung disease, collectively known as PCWH. Meanwhile, SOX10 haploinsufficiency caused by allelic loss-of-function mutations leads to a milder non-neurological disorder, Waardenburg-Hirschsprung disease. The cellular pathogenesis of more complex PCWH phenotypes in vivo has not been thoroughly understood. To determine the pathogenesis of PCWH, we have established a transgenic mouse model. A known PCWH-causing SOX10 mutation, c.1400del12, was introduced into mouse Sox10-expressing cells by means of bacterial artificial chromosome (BAC) transgenesis. By crossing the multiple transgenic lines, we examined the effects produced by various copy numbers of the mutant transgene. Within the nervous systems, transgenic mice revealed a delay in the incorporation of Schwann cells in the sciatic nerve and the terminal differentiation of oligodendrocytes in the spinal cord. Transgenic mice also showed defects in melanocytes presenting as neurosensory deafness and abnormal skin pigmentation, and a loss of the enteric nervous system. Phenotypes in each lineage were more severe in mice carrying higher copy numbers, suggesting a gene dosage effect for mutant SOX10. By uncoupling the effects of gain-of-function and haploinsufficiency in vivo, we have demonstrated that the effect of a PCWH-causing SOX10 mutation is solely pathogenic in each SOX10-expressing cellular lineage in a dosage-dependent manner. In both the peripheral and central nervous systems, the primary consequence of SOX10 mutations is hypomyelination. The complex neurological phenotypes in PCWH patients likely result from a combination of haploinsufficiency and additive dominant effect. PMID:25959061

  2. Effective Temperature of Mutations

    Derényi, Imre; Szöllősi, Gergely J.

    2015-02-01

    Biological macromolecules experience two seemingly very different types of noise acting on different time scales: (i) point mutations corresponding to changes in molecular sequence and (ii) thermal fluctuations. Examining the secondary structures of a large number of microRNA precursor sequences and model lattice proteins, we show that the effects of single point mutations are statistically indistinguishable from those of an increase in temperature by a few tens of kelvins. The existence of such an effective mutational temperature establishes a quantitative connection between robustness to genetic (mutational) and environmental (thermal) perturbations.

  3. Simultaneous Estimation of Additive and Mutational Genetic Variance in an Outbred Population of Drosophila serrata.

    McGuigan, Katrina; Aguirre, J David; Blows, Mark W

    2015-11-01

    How new mutations contribute to genetic variation is a key question in biology. Although the evolutionary fate of an allele is largely determined by its heterozygous effect, most estimates of mutational variance and mutational effects derive from highly inbred lines, where new mutations are present in homozygous form. In an attempt to overcome this limitation, middle-class neighborhood (MCN) experiments have been used to assess the fitness effect of new mutations in heterozygous form. However, because MCN populations harbor substantial standing genetic variance, estimates of mutational variance have not typically been available from such experiments. Here we employ a modification of the animal model to analyze data from 22 generations of Drosophila serrata bred in an MCN design. Mutational heritability, measured for eight cuticular hydrocarbons, 10 wing-shape traits, and wing size in this outbred genetic background, ranged from 0.0006 to 0.006 (with one exception), a similar range to that reported from studies employing inbred lines. Simultaneously partitioning the additive and mutational variance in the same outbred population allowed us to quantitatively test the ability of mutation-selection balance models to explain the observed levels of additive and mutational genetic variance. The Gaussian allelic approximation and house-of-cards models, which assume real stabilizing selection on single traits, both overestimated the genetic variance maintained at equilibrium, but the house-of-cards model was a closer fit to the data. This analytical approach has the potential to be broadly applied, expanding our understanding of the dynamics of genetic variance in natural populations. PMID:26384357

  4. MTHFR homozygous mutation and additional risk factors for cerebral infarction in a large Italian family.

    Del Balzo, Francesca; Spalice, Alberto; Perla, Massimo; Properzi, Enrico; Iannetti, Paola

    2009-01-01

    Several cases with cerebral infarctions associated with the C677T mutation in the methylenetetrahydrofolate reductase gene (MTHFR) have been reported. Given the large number of asymptomatic individuals with the MTHFR mutation, additional risk factors for cerebral infarction should be considered. This study describes a large family with the MTHFR mutation and a combination of heterozygous factor V Leiden mutations and different additional exogenous and endogenous thrombogenic risk factors. Psychomotor retardation and a left fronto-insular infarct associated with the MTHFR mutation together with diminished factor VII and low level of protein C was documented in the first patient. In the second patient, generalized epilepsy and a malacic area in the right nucleus lenticularis was associated with the MTHFR mutation and a low level of protein C. In the third patient, right hemiparesis and a left fronto-temporal porencephalic cyst were documented, together with the MTHFR mutation and hyperhomocysteinemia. An extensive search of additional circumstantial and genetic thrombogenic risk factors should be useful for prophylaxis and prognosis of infants with cerebral infarctions associated with the MTHFR mutation and of their related family members. PMID:19068258

  5. Identification of additional IDH mutations associated with oncometabolite R(-)-2-hydroxyglutarate production

    Ward, Patrick S.; Cross, Justin R.; Lu, Chao; Weigert, Oliver; Abel-Wahab, Omar; Levine, Ross L.; Weinstock, David M.; SHARP, KIM A.; Thompson, Craig B.

    2011-01-01

    Mutationsin cytosolic isocitrate dehydrogenase 1 (IDH1) or its mitochondrial homolog IDH2 can lead to R(-)-2-hydroxyglutarate (2HG) production. To date, mutations in three active site arginine residues IDH1 R132, IDH2 R172, and IDH2 R140 have been shown to result in the neomorphic production of 2HG. Here we report three additional 2HG-producing IDH1 mutations: IDH1 R100 which is affected in adult glioma, IDH1 G97 which is mutated in colon cancer cell lines and pediatric glioblastoma, and IDH1...

  6. Systematic Mapping of Protein Mutational Space by Prolonged Drift Reveals the Deleterious Effects of Seemingly Neutral Mutations.

    Liat Rockah-Shmuel

    2015-08-01

    Full Text Available Systematic mappings of the effects of protein mutations are becoming increasingly popular. Unexpectedly, these experiments often find that proteins are tolerant to most amino acid substitutions, including substitutions in positions that are highly conserved in nature. To obtain a more realistic distribution of the effects of protein mutations, we applied a laboratory drift comprising 17 rounds of random mutagenesis and selection of M.HaeIII, a DNA methyltransferase. During this drift, multiple mutations gradually accumulated. Deep sequencing of the drifted gene ensembles allowed determination of the relative effects of all possible single nucleotide mutations. Despite being averaged across many different genetic backgrounds, about 67% of all nonsynonymous, missense mutations were evidently deleterious, and an additional 16% were likely to be deleterious. In the early generations, the frequency of most deleterious mutations remained high. However, by the 17th generation, their frequency was consistently reduced, and those remaining were accepted alongside compensatory mutations. The tolerance to mutations measured in this laboratory drift correlated with sequence exchanges seen in M.HaeIII's natural orthologs. The biophysical constraints dictating purging in nature and in this laboratory drift also seemed to overlap. Our experiment therefore provides an improved method for measuring the effects of protein mutations that more closely replicates the natural evolutionary forces, and thereby a more realistic view of the mutational space of proteins.

  7. Cellular effects of LRRK2 mutations

    Cookson, Mark R.

    2012-01-01

    Mutations in leucine-rich repeat kinase 2 (LRRK2) are a relatively common cause of inherited Parkinson's disease (PD) but the mechanism(s) by which mutations lead to disease are poorly understood. Here, I will discuss what is known about LRRK2 in cellular models, focusing on specifically on assays that have been used to tease apart the effects of LRRK2 mutations on cellular phenotypes. LRRK2 expression has been suggested to cause loss of neuronal viability, although because it also has a stro...

  8. Additive decompositions with interaction effects

    Biewen, Martin

    2012-01-01

    This paper proposes a comprehensive, path-independent decomposition formula of changes into ceteris paribus effects and interaction effects. The formula implies a reassessment of sequential decomposition methods that are widely used in the literature and that are restrictive in how they treat interaction effects. If counterfactual outcomes are correctly specified, it may also be viewed as a description of certain aspects of causality in the situation where more than one causal influence is pr...

  9. Beyond Mutations: Additional Mechanisms and Implications of SWI/SNF Complex Inactivation

    Stefanie eMarquez

    2015-02-01

    Full Text Available SWI/SNF is a major regulator of gene expression. Its role is to facilitate the shifting and exposure of DNA segments within the promoter and other key domains to transcription factors and other essential cellular proteins. This complex interacts with a wide range of proteins and does not function within a single, specific pathway; thus, it is involved in a multitude of cellular processes, including DNA repair, differentiation, development, cell adhesion, and growth control. Given SWI/SNF’s prominent role in these processes, many of which are important for blocking cancer development, it is not surprising that the SWI/SNF complex is targeted during cancer initiation and progression both by mutations and by nonmutational mechanisms. Currently, the understanding of the types of alterations, their frequency, and their impact on the SWI/SNF subunits is an area of intense research that has been bolstered by a recent cadre of NextGen sequencing studies. These studies have revealed mutations in SWI/SNF subunits, indicating that this complex is thus important for cancer development. The purpose of this review is to put into perspective the role of mutations versus other mechanisms in the silencing of SWI/SNF subunits, in particular, BRG1 and BRM. In addition, this review explores the recent development of synthetic lethality and how it applies to this complex, as well as how BRM polymorphisms are becoming recognized as potential clinical biomarkers for cancer risk.

  10. BRAF mutation in papillary thyroid microcarcinoma – additional marker of risk stratification

    Dmitriy Yuriyevich Semyonov

    2014-11-01

    Full Text Available BackgroundPapillary thyroid microcarcinoma (PTMC is heterogeneous group of tumor less than 1 cm in the diameter. The volume of surgical treatment stay unstable because unclear biological potential of PTMC.AimThe aim of our study was to assess the utility of BRAF gene mutation as preoperative additional marker of risk stratification.Materials and methodsWe include 44 patient who were operated in general surgery department Pavlov State Medical University from 2001 to 2013. In all 44 cases BRAF gene mutation was detected and compared with clinic-morphological features (multifocality, invasive growth, lymph node metastasis, recurrence retrospectivelyResultsIn our study the frequency of BRAF gene mutation was 68.2%. On multivariate regression analysis the presence of bilateral tumoural foci, lymph node metastasis and the presence of capsular invasion were significantly related to BRAF positive gene status.ConclusionsThus, appropriate volume for the BRAF positive PTMC is thyroidectomy with central compartment lymph node dissection.

  11. Islet-intrinsic effects of CFTR mutation.

    Koivula, Fiona N Manderson; McClenaghan, Neville H; Harper, Alan G S; Kelly, Catriona

    2016-07-01

    Cystic fibrosis-related diabetes (CFRD) is the most significant extra-pulmonary comorbidity in cystic fibrosis (CF) patients, and accelerates lung decline. In addition to the traditional view that CFRD is a consequence of fibrotic destruction of the pancreas as a whole, emerging evidence may implicate a role for cystic fibrosis transmembrane-conductance regulator (CFTR) in the regulation of insulin secretion from the pancreatic islet. Impaired first-phase insulin responses and glucose homeostasis have also been reported in CF patients. CFTR expression in both human and mouse beta cells has been confirmed, and recent studies have shown differences in endocrine pancreatic morphology from birth in CF. Recent experimental evidence suggests that functional CFTR channels are required for insulin exocytosis and the regulation of membrane potential in the pancreatic beta cell, which may account for the impairments in insulin secretion observed in many CF patients. These novel insights suggest that the pathogenesis of CFRD is more complicated than originally thought, with implications for diabetes treatment and screening in the CF population. This review summarises recent emerging evidence in support of a primary role for endocrine pancreatic dysfunction in the development of CFRD. Summary • CF is an autosomal recessive disorder caused by mutations in the CFTR gene • The vast majority of morbidity and mortality in CF results from lung disease. However CFRD is the largest extra-pulmonary co-morbidity and rapidly accelerates lung decline • Recent experimental evidence shows that functional CFTR channels are required for normal patterns of first phase insulin secretion from the pancreatic beta cell • Current clinical recommendations suggest that insulin is more effective than oral glucose-lowering drugs for the treatment of CFRD. However, the emergence of CFTR corrector and potentiator drugs may offer a personalised approach to treating diabetes in the CF population

  12. Studies on biological effects of ion beams on lethality, molecular nature of mutation, mutation rate, and spectrum of mutation phenotype for mutation breeding in higher plants

    Recently, heavy ions or ion beams have been used to generate new mutants or varieties, especially in higher plants. It has been found that ion beams show high relative biological effectiveness (RBE) of growth inhibition, lethality, and so on, but the characteristics of ion beams on mutation have not been clearly elucidated. To understand the effect of ion beams on mutation induction, mutation rates were investigated using visible known Arabidopsis mutant phenotypes, indicating that mutation frequencies induced by carbon ions were 20-fold higher than by electrons. In chrysanthemum and carnation, flower-color and flower-form mutants, which are hardly produced by gamma rays or X rays, were induced by ion beams. Novel mutants and their responsible genes, such as UV-B resistant, serrated petals and sepals, anthocyaninless, etc. were induced by ion beams. These results indicated that the characteristics of ion beams for mutation induction are high mutation frequency and broad mutation spectrum and therefore, efficient induction of novel mutants. On the other hand, PCR and sequencing analyses showed that half of all mutants induced by ion beams possessed large DNA alterations, while the rest had point-like mutations. Both mutations induced by ion beams had a common feature that deletion of several bases were predominantly induced. It is plausible that ion beams induce a limited amount of large and irreparable DNA damage, resulting in production of a null mutation that shows a new mutant phenotype. (author)

  13. The Oenothera plastome mutator: effect of UV irradiation and nitroso-methyl urea on mutation frequencies

    Oenothera plants homozygous for a recessive plastome mutator allele (pm) showed spontaneous mutation frequencies for plastome genes that are 200-fold higher than spontaneous levels. Mutations occurred at high frequencies in plants grown in the field, in a glasshouse, or as leaf tip cultures under fluorescent light, indicating that the plastome mutator activity is UV-independent. However, the chlorotic sectors became visible at an earlier stage of development when seedlings were irradiated, compared to seedlings that were not exposed to UV. These results imply that the rate of sorting-out was increased by the irradiation treatment, possibly due to a decrease in the effective number of multiplication-competent plastids, or a reduction in the extent of cytoplasmic mixing. Nitroso-methyl urea treatment of seeds had a dramatic effect on mutation frequency in both wild-type and plastome mutator samples. When the background mutation rates were low, the combination of the plastome mutator nucleus and the chemical mutagenesis treatment resulted in a synergistic effect, suggesting that the plastome mutator may involve a cpDNA repair pathway. (author)

  14. A DSPP Mutation Causing Dentinogenesis Imperfecta and Characterization of the Mutational Effect

    Sook-Kyung Lee

    2013-01-01

    Full Text Available Mutations in the DSPP gene have been identified in nonsyndromic hereditary dentin defects, but the genotype-phenotype correlations are not fully understood. Recently, it has been demonstrated that the mutations of DSPP affecting the IPV leader sequence result in mutant DSPP retention in rough endoplasmic reticulum (ER. In this study, we identified a Korean family with dentinogenesis imperfecta type III. To identify the disease causing mutation in this family, we performed mutational analysis based on candidate gene sequencing. Exons and exon-intron boundaries of DSPP gene were sequenced, and the effects of the identified mutation on the pre-mRNA splicing and protein secretion were investigated. Candidate gene sequencing revealed a mutation (c.50C > T, p.P17L in exon 2 of the DSPP gene. The splicing assay showed that the mutation did not influence pre-mRNA splicing. However, the mutation interfered with protein secretion and resulted in the mutant protein remaining largely in the ER. These results suggest that the mutation affects ER-to-Golgi apparatus export and results in the reduction of secreted DSPP and ER overload. This may induce cell stress and damage processing and/or transport of dentin matrix proteins or other critical proteins.

  15. Environmental stresses can alleviate the average deleterious effect of mutations

    Leibler Stanislas

    2003-05-01

    Full Text Available Abstract Background Fundamental questions in evolutionary genetics, including the possible advantage of sexual reproduction, depend critically on the effects of deleterious mutations on fitness. Limited existing experimental evidence suggests that, on average, such effects tend to be aggravated under environmental stresses, consistent with the perception that stress diminishes the organism's ability to tolerate deleterious mutations. Here, we ask whether there are also stresses with the opposite influence, under which the organism becomes more tolerant to mutations. Results We developed a technique, based on bioluminescence, which allows accurate automated measurements of bacterial growth rates at very low cell densities. Using this system, we measured growth rates of Escherichia coli mutants under a diverse set of environmental stresses. In contrast to the perception that stress always reduces the organism's ability to tolerate mutations, our measurements identified stresses that do the opposite – that is, despite decreasing wild-type growth, they alleviate, on average, the effect of deleterious mutations. Conclusions Our results show a qualitative difference between various environmental stresses ranging from alleviation to aggravation of the average effect of mutations. We further show how the existence of stresses that are biased towards alleviation of the effects of mutations may imply the existence of average epistatic interactions between mutations. The results thus offer a connection between the two main factors controlling the effects of deleterious mutations: environmental conditions and epistatic interactions.

  16. Effective Structural Health Monitoring with Additive Manufacturing

    De Baere, Dieter; Strantza, Maria; Hinderdael, Michaël; Devesse, Wim; Guillaume, Patrick

    2014-01-01

    The current remaining challenges for structural health monitoring (SHM) systems prevented the introduction of SHM systems on a large scale within industrial applications. An effective SHM system is required for the reduction of the direct operation costs, improvement of the life-safety and the introduction of additive manufactured components for critical structures. In this paper, a new structural health monitoring methodology will be presented for components that can be processed by additive...

  17. EGFR mutation frequency and effectiveness of erlotinib

    Weber, Britta; Hager, Henrik; Sorensen, Boe S;

    2014-01-01

    OBJECTIVES: In 2008, we initiated a prospective study to explore the frequency and predictive value of epidermal growth factor receptor (EGFR) mutations in an unselected population of Danish patients with non-small cell lung cancer offered treatment with erlotinib, mainly in second-line. MATERIAL...

  18. Sintering of magnesia: effect of additives

    Satyananda Behera; Ritwik Sarkar

    2015-10-01

    Effect of different additives, namely Cr2O3, Fe2O3 and TiO2, up to 2 wt% was studied on the sintering and microstructural developments of the chemically pure magnesia using the pressureless sintering technique between 1500 and 1600° C. Sintering was evaluated by per cent densification and microstructural developments were studied by electron microscopy and elemental distribution of the additives in the sintered products was also investigated for their distribution in the matrix. Cr2O3 and TiO2 were found to deteriorate the densification associated with grain growth. Fe2O3 was found to improve the densification and well-compacted grain distribution was observed in the microstructure.

  19. Effect of space mutation of photosynthetic characteristics of soybean varieties

    In order to elucidate the response of the photosynthetic traits of soybean to space mutation, three soybean varieties (lines) of Heinong 48, Heinong 44 and Ha 2291-Y were carried by artificial satellite in 2006 and the net photo synthetic rate (Pn), stomatal conductance (Cond), intercellular CO2 concentration (Ci) and stomatal resistance (Rs) from SP1 to SP4 generation were determined. The results showed that space mutation affected photosynthesis traits of soy bean. The photosynthetic rate of soybean varieties by space mutation occurred different levels of genetic variation and the positive mutation rate were higher. Coefficient of variation among generations were SP2 >SP3 >SP4 >CK. Results suggest that space mutation can effectively create soybean materials with higher photosynthetic rate. (authors)

  20. Addition agents effects on hydrocarbon fuels burning

    Larionov, V. M.; Mitrofanov, G. A.; Sakhovskii, A. V.

    2016-01-01

    Literature review on addition agents effects on hydrocarbon fuels burning has been conducted. The impact results in flame pattern and burning velocity change, energy efficiency increase, environmentally harmful NOx and CO emission reduction and damping of self-oscillations in flow. An assumption about water molecules dissociation phenomenon existing in a number of practical applications and being neglected in most explanations for physical- chemical processes taking place in case of injection of water/steam into combustion zone has been noted. The hypothesis about necessity of water dissociation account has been proposed. It can be useful for low temperature combustion process control and NOx emission reduction.

  1. Chlorambucil effectively induces deletion mutations in mouse germ cells.

    Russell, L B; Hunsicker, P R; Cacheiro, N L; Bangham, J W; Russell, W. L.; Shelby, M D

    1989-01-01

    The chemotherapeutic agent chlorambucil was found to be more effective than x-rays or any chemical investigated to date in inducing high yields of mouse germ-line mutations that appear to be deletions or other structural changes. Induction of mutations involving seven specific loci was studied after exposures of various male germ-cell stages to chlorambucil at 10-25 mg/kg. A total of 60,750 offspring was scored. Mutation rates in spermatogonial stem cells were not significantly increased over...

  2. New approaches for effective mutation induction in gamma field

    The purpose of the report is to clarify the effects of chronic irradiation using in vitro culture on inducing the mutation of two model plants. Culture technique combined with irradiation can overcome the problem of chimera formation and provided 10 times greater mutation efficiency than conventional method. Proper mutagenic treatment using cultured materials is indispensable to effective mutation induction. The chronic culture method showed the widest color spectrum in chrysanthemum and extended toward not only the negative but positive direction. However, the acute culture methods indicated a relatively low mutation rate and a very limited flower color spectrum. Flower color mutation of the regenerations could be induced more from petals and buds than from leaves. These facts is supposed that the gene loci fully expressed on floral organs may be unstable for mutation by mutagenesis or culture. It may be likely to control a direction of desired mutation. One possible reason why the chronic culture methods showed higher frequencies is that most of the cells composing the tissue and organs continually irradiated into a cell division which was highly sensitive and more mutable to irradiation. Under these conditions, many mutated sectors may accumulate in the cells of the growing organs. Regenerated mutant lines show remarkable decrease of chromosome numbers by irradiation. It is a proper indicator to monitor radiation damage. In this study, the six flower color mutant varieties registered were derived from chronic irradiation. The combined method of chronic irradiation with floral organ cultures proved to be of particularly great practical use in mutation breeding for not only flower species but any other species. (author)

  3. New approaches for effective mutation induction in gamma field

    Nagatomi, Shigeki [National Institute of Agrobiological Resources, Institute of Radiation Breeding, Omiya, Ibaraki (Japan)

    2001-03-01

    The purpose of the report is to clarify the effects of chronic irradiation using in vitro culture on inducing the mutation of two model plants. Culture technique combined with irradiation can overcome the problem of chimera formation and provided 10 times greater mutation efficiency than conventional method. Proper mutagenic treatment using cultured materials is indispensable to effective mutation induction. The chronic culture method showed the widest color spectrum in chrysanthemum and extended toward not only the negative but positive direction. However, the acute culture methods indicated a relatively low mutation rate and a very limited flower color spectrum. Flower color mutation of the regenerations could be induced more from petals and buds than from leaves. These facts is supposed that the gene loci fully expressed on floral organs may be unstable for mutation by mutagenesis or culture. It may be likely to control a direction of desired mutation. One possible reason why the chronic culture methods showed higher frequencies is that most of the cells composing the tissue and organs continually irradiated into a cell division which was highly sensitive and more mutable to irradiation. Under these conditions, many mutated sectors may accumulate in the cells of the growing organs. Regenerated mutant lines show remarkable decrease of chromosome numbers by irradiation. It is a proper indicator to monitor radiation damage. In this study, the six flower color mutant varieties registered were derived from chronic irradiation. The combined method of chronic irradiation with floral organ cultures proved to be of particularly great practical use in mutation breeding for not only flower species but any other species. (author)

  4. Effects of intronic mutations in the LDLR gene on pre-mRNA splicing: Comparison of wet-lab and bioinformatics analyses

    O.L. Holla; S. Nakken; M. Mattingsdal; T. Ranheim; K.E. Berge; J.C. Defesche; T.P. Leren

    2009-01-01

    Screening for mutations in the low density lipoprotein receptor (LDLR) gene has identified more than 1000 mutations as the cause of familial hypercholesterolemia (FH). In addition, numerous intronic mutations with uncertain effects on pre-mRNA splicing have also been identified. In this study, we ha

  5. Risk of venous thrombosis: obesity and its joint effect with oral contraceptive use and prothrombotic mutations

    Pomp, Elisabeth R.; Cessie, le Saskia; Rosendaal, Frits R.; Doggen, Carine J.M.

    2007-01-01

    In the Multiple Environmental and Genetic Assessment of risk factors for venous thrombosis (MEGA study), body weight, height and body mass index (BMI) were evaluated as risk factors. Additionally, the joint effect of obesity together with oral contraceptive use and prothrombotic mutations on the ris

  6. Food Additives and Effects to Human Health

    Ayper Boga; Secil Binokay

    2010-01-01

    Food purchasing patterns have changed dramatically over the past fifty years. Packaged and processed foods get many a family through the day. They’re convenient, portable, and they stay fresh for a long time. There are over fourteen thousand man-made chemicals added to American food supply today. Food additives are not natural nutrition for humans or their pets. Children are suffering the most from food additives because they are exposed to food chemicals from infancy, and human bodies w...

  7. Nurse Scheduling by Cooperative GA with Effective Mutation Operator

    Ohki, Makoto

    In this paper, we propose an effective mutation operators for Cooperative Genetic Algorithm (CGA) to be applied to a practical Nurse Scheduling Problem (NSP). The nurse scheduling is a very difficult task, because NSP is a complex combinatorial optimizing problem for which many requirements must be considered. In real hospitals, the schedule changes frequently. The changes of the shift schedule yields various problems, for example, a fall in the nursing level. We describe a technique of the reoptimization of the nurse schedule in response to a change. The conventional CGA is superior in ability for local search by means of its crossover operator, but often stagnates at the unfavorable situation because it is inferior to ability for global search. When the optimization stagnates for long generation cycle, a searching point, population in this case, would be caught in a wide local minimum area. To escape such local minimum area, small change in a population should be required. Based on such consideration, we propose a mutation operator activated depending on the optimization speed. When the optimization stagnates, in other words, when the optimization speed decreases, the mutation yields small changes in the population. Then the population is able to escape from a local minimum area by means of the mutation. However, this mutation operator requires two well-defined parameters. This means that user have to consider the value of these parameters carefully. To solve this problem, we propose a periodic mutation operator which has only one parameter to define itself. This simplified mutation operator is effective over a wide range of the parameter value.

  8. Dominance effects of deleterious and beneficial mutations in a single gene of the RNA virus ϕ6.

    Sarah B Joseph

    Full Text Available Most of our knowledge of dominance stems from studies of deleterious mutations. From these studies we know that most deleterious mutations are recessive, and that this recessivity arises from a hyperbolic relationship between protein function (i.e., protein concentration or activity and fitness. Here we investigate whether this knowledge can be used to make predictions about the dominance of beneficial and deleterious mutations in a single gene. We employed a model system--the bacteriophage φ6--that allowed us to generate a collection of mutations in haploid conditions so that it was not biased toward either dominant beneficial or recessive deleterious mutations. Screening for the ability to infect a bacterial host that does not permit infection by the wildtype φ6, we generated a collection of mutations in P3, a gene involved in attachment to the host and in phage particle assembly. The resulting collection contained mutations with both deleterious and beneficial effects on fitness. The deleterious mutations in our collection had additive effects on fitness and the beneficial mutations were recessive. Neither of these observations were predicted from previous studies of dominance. This pattern is not consistent with the hyperbolic (diminishing returns relationship between protein function and fitness that is characteristic of enzymatic genes, but could have resulted from a curve of increasing returns.

  9. Rosiglitazone and Fenofibrate Additive Effects on Lipids

    Ahmad Slim

    2011-01-01

    Full Text Available Background. To evaluate the effect of rosiglitazone, fenofibrate, or their combined use on plasma lipids in normoglycemic healthy adults. Methods and Results. Subjects were randomized in a double-blind fashion to rosiglitazone + placebo, fenofibrate + placebo, rosiglitazone + fenofibrate, or matching double placebo. The between-group difference in the change in fasting TG, high-density lipoprotein cholesterol (HDL-C, LDL-C, and plasma apolipoproteins A-I, A-II, and C-III level were compared after 12 weeks of treatment. A total of 548 subjects were screened and 41 met the inclusion criteria. After 12 weeks of therapy, the median change in the triglyceride levels showed a significant reduction ranging from 47 to 55 mg per deciliter in the fenofibrate only and rosiglitazone/fenofibrate groups compared with placebo (=0.0496. However, the rosiglitazone only group did not show significant change in triglyceride level. The change in the Apo AII showed increase in all the treatment groups compared with placebo (=0.009. There was also significant change in the Apo CIII that showed reduction of its level in the fenofibrate only and rosiglitazone/fenofibrate groups (=0.0003. Conclusion. Rosiglitazone does not appear to modulate hypertriglyceridemia in patients with elevated triglycerides independent of glucose metabolism.

  10. Somatic mutations in Tradescantia as a model system for studying the effects of the environmental agents

    The application of the plant model system for studying the biological effects of ionizing radiation and chemical mutagens is presented. The model system is based on the somatic mutation frequency in stamen hair cells of Tradescantia clones heterosygous for flower color. The interaction of chemical mutagens with radiation in the induction of somatic mutations was investigated. The results demonstrate the synergistic interaction between radiation and chemical mutagens like ethyl methanesulfonate and di-bromoethane. The synergistic effect is clearly manifested after combined treatment with radiation and chemicals. In the low dose region the effect depends on the radiation dose and chemical exposure. Other results show the influence of the fluoride treatment on the radiation effect. The fluoride treatment is likely to alter the DNA double strand breaks repair processes. Additionally the usefulness of the model system for studying the mutagenic effectiveness of the pollution in the ambient air is presented. 148 refs. (author)

  11. Additional mutations in SRSF2, ASXL1 and/or RUNX1 identify a high-risk group of patients with KIT D816V(+) advanced systemic mastocytosis.

    Jawhar, M; Schwaab, J; Schnittger, S; Meggendorfer, M; Pfirrmann, M; Sotlar, K; Horny, H-P; Metzgeroth, G; Kluger, S; Naumann, N; Haferlach, C; Haferlach, T; Valent, P; Hofmann, W-K; Fabarius, A; Cross, N C P; Reiter, A

    2016-01-01

    Most patients with KIT D816V(+) advanced systemic mastocytosis (SM) are characterized by somatic mutations in additional genes. We sought to clarify the prognostic impact of such mutations. Genotype and clinical characteristics of 70 multi-mutated KIT D816V(+) advanced SM patients were included in univariate and multivariate analyses. The most frequently identified mutated genes were TET2 (n=33 of 70 patients), SRSF2 (n=30), ASXL1 (n=20), RUNX1 (n=16) and JAK2 (n=11). In univariate analysis, overall survival (OS) was adversely influenced by mutations in SRSF2 (P<0.0001), ASXL1 (P=0.002) and RUNX1 (P=0.03), but was not influenced by mutations in TET2 or JAK2. In multivariate analysis, SRSF2 and ASXL1 remained the most predictive adverse indicators concerning OS. Furthermore, we found that inferior OS and adverse clinical characteristics were significantly influenced by the number of mutated genes in the SRSF2/ASXL1/RUNX1 (S/A/R) panel (P<0.0001). In conclusion, the presence and number of mutated genes within the S/A/R panel are adversely associated with advanced disease and poor survival in KIT D816V(+) SM. On the basis of these findings, inclusion of molecular markers should be considered in upcoming prognostic scoring systems for patients with SM. PMID:26464169

  12. Mutational Effects on the Folding Dynamics of a Minimized Hairpin‡

    Scian, Michele; Shu, Irene; Olsen, Katherine A.; Hassam, Khalil; Andersen, Niels H.

    2013-01-01

    The fold stabilities and folding dynamics of a series of mutants of a model hairpin, KTW-NPATGK-WTE (HP7), are reported. The parent system and the corresponding DPATGK loop species display sub-μs folding time constants. The mutational studies revealed that ultrafast folding requires both some pre-structuring of the loop and a favorable interaction between the chain termini at the transition state. In the case of YY-DPETGT-WY, another sub-μs folding species [Davis, C. M.; Xiao, S.; Raleigh, D. P.; Dyer, R. B. (2012) J. Am. Chem. Soc. 134, 14476–14482], a hydrophobic cluster provides the latter. In the case of HP7, the Coulombic interaction between the terminal NH3+ and CO2− units provides this; a C-terminal Glu to amidated Ala mutation results in a 5-fold folding rate retardation. The effects of mutations within the reversing loop indicate the balance between loop flexibility (favoring fast conformational searching) and turn-formation in the unfolded state is a major factor in determining the folding dynamics. The –NAAAKX- loops examined display no detectable turn formation propensity in other hairpin constructs, but do result in stable analogs of HP7. Peptide KTW-NAAAKK-WTE displays the same fold stability as HP7 but both the folding and unfolding time constants are greater by a factor of 20. PMID:23521619

  13. Mutational effects on the folding dynamics of a minimized hairpin.

    Scian, Michele; Shu, Irene; Olsen, Katherine A; Hassam, Khalil; Andersen, Niels H

    2013-04-16

    The fold stabilities and folding dynamics of a series of mutants of a model hairpin, KTW-NPATGK-WTE (HP7), are reported. The parent system and the corresponding DPATGK loop species display submicrosecond folding time constants. The mutational studies revealed that ultrafast folding requires both some prestructuring of the loop and a favorable interaction between the chain termini in the transition state. In the case of YY-DPETGT-WY, another submicrosecond folding species [Davis, C. M., Xiao, S., Raleigh, D. P., and Dyer, R. B. (2012) J. Am. Chem. Soc. 134, 14476-14482], a hydrophobic cluster provides the latter. In the case of HP7, the Coulombic interaction between the terminal NH3(+) and CO2(-) units provides this; a C-terminal Glu to amidated Ala mutation results in a 5-fold retardation of the folding rate. The effects of mutations within the reversing loop indicate the balance between loop flexibility (favoring fast conformational searching) and turn formation in the unfolded state is a major factor in determining the folding dynamics. The -NAAAKX- loops examined display no detectable turn formation propensity in other hairpin constructs but do result in stable analogues of HP7. Peptide KTW-NAAAKK-WTE displays the same fold stability as HP7, but both the folding and unfolding time constants are greater by a factor of 20. PMID:23521619

  14. Point Mutations Effects on Charge Transport Properties of the Tumor-Suppressor Gene p53

    Shih, Chi-Tin; Roche, Stephan; Römer, Rudolf A.

    2007-01-01

    We report on a theoretical study of point mutations effects on charge transfer properties in the DNA sequence of the tumor-suppressor p53 gene. On the basis of effective single-strand or double-strand tight-binding models which simulate hole propagation along the DNA, a statistical analysis of charge transmission modulations associated with all possible point mutations is performed. We find that in contrast to non-cancerous mutations, mutation hotspots tend to result in significantly weaker {...

  15. Computing Stability Effects of Mutations in Human Superoxide Dismutase 1

    Kepp, Kasper Planeta

    2014-01-01

    physiological importance. In this work, stability changes of SOD1 mutations were computed with five methods, CUPSAT, I-Mutant2.0, I-Mutant3.0, PoPMuSiC, and SDM, with emphasis on structural sensitivity as a potential issue in structure-based protein calculation. The large correlation between experimental...... interest, but had little impact on overall batch estimates. Protein-interaction effects (as a mimic of crystal packing) were small for the more accurate methods. Thus, batch computations, relevant to, e.g., comparisons of disease/nondisease mutant sets or different clades in phylogenetic trees, are much...

  16. Assessment of computational methods for predicting the effects of missense mutations in human cancers

    Gnad, Florian; Baucom, Albion; Mukhyala, Kiran; Manning, Gerard; Zhang, Zemin

    2013-01-01

    Background Recent advances in sequencing technologies have greatly increased the identification of mutations in cancer genomes. However, it remains a significant challenge to identify cancer-driving mutations, since most observed missense changes are neutral passenger mutations. Various computational methods have been developed to predict the effects of amino acid substitutions on protein function and classify mutations as deleterious or benign. These include approaches that rely on evolution...

  17. A rapid, sensitive, reproducible and cost-effective method for mutation profiling of colon cancer and metastatic lymph nodes

    An increasing number of studies show that genetic markers can aid in refining prognostic information and predicting the benefit from systemic therapy. Our goal was to develop a high throughput, cost-effective and simple methodology for the detection of clinically relevant hot spot mutations in colon cancer. The Maldi-Tof mass spectrometry platform and OncoCarta panel from Sequenom were used to profile 239 colon cancers and 39 metastatic lymph nodes from NSABP clinical trial C-07 utilizing routinely processed FFPET (formalin-fixed paraffin-embedded tissue). Among the 238 common hot-spot cancer mutations in 19 genes interrogated by the OncoCarta panel, mutations were detected in 7 different genes at 26 different nucleotide positions in our colon cancer samples. Twenty-four assays that detected mutations in more than 1% of the samples were reconfigured into a new multiplexed panel, termed here as ColoCarta. Mutation profiling was repeated on 32 mutant samples using ColoCarta and the results were identical to results with OncoCarta, demonstrating that this methodology was reproducible. Further evidence demonstrating the validity of the data was the fact that the mutation frequencies of the most common colon cancer mutations were similar to the COSMIC (Catalog of Somatic Mutations in Cancer) database. The frequencies were 43.5% for KRAS, 20.1% for PIK3CA, and 12.1% for BRAF. In addition, infrequent mutations in NRAS, AKT1, ABL1, and MET were detected. Mutation profiling of metastatic lymph nodes and their corresponding primary tumors showed that they were 89.7% concordant. All mutations found in the lymph nodes were also found in the corresponding primary tumors, but in 4 cases a mutation was present in the primary tumor only. This study describes a high throughput technology that can be used to interrogate DNAs isolated from routinely processed FFPET and identifies the specific mutations that are common to colon cancer. The development of this technology and the Colo

  18. Use of amplification refractory mutation system PCR assay as a simple and effective tool to detect HIV-1 drug resistance mutations.

    Nanfack, Aubin J; Agyingi, Lucy; Noubiap, Jean Jacques N; Ngai, Johnson N; Colizzi, Vittorio; Nyambi, Phillipe N

    2015-05-01

    Access to genotyping assays to determine successful antiretroviral treatment (ART) is limited in resource-constrained settings by high cost, suggesting the need for a cost-effective and simplified method to identify HIV-1 drug resistance (HIVDR) mutations. In this study, an amplification refractory mutation system (ARMS)-PCR assay was developed and used to investigate the most frequent HIVDR mutations affecting first-line ART in settings where WHO ART guidelines are applied. Seventy-five HIV-positive (HIV(+)) samples from Cameroon were used to assess the performance of this assay. Sequencing of HIV-1 reverse transcriptase was simultaneously performed for comparison, and discordant samples were tested with a Trugene HIV-1 genotyping kit. The ARMS-PCR assay was able to detect M184V, T215Y/F, K103N, and Y181C mutations with sensitivities of 96.8%, 85.7%, 91.3%, and 70%, respectively, and specificities of 90.6%, 95%, 100%, 96.9%, respectively, compared with data on sequencing. The results indicated the highest positive predictive value for K103N (100%) and the highest negative predictive value for M184V (97.5%). ARMS-PCR's limits of detection for mutations M184V, T215Y/F, K103N, and Y181C were HIV-1 clades (CRF02_AG and non-CRF02_AG). In addition, this approach was more cost-effective than other genotyping assays. The high throughput, the cost-effectiveness, and the simplicity of the ARMS-PCR assay make it a suitable tool to monitor HIVDR patterns in resource-constrained settings with broad HIV-1 genetic diversity. PMID:25788547

  19. Downstream effects of plectin mutations in epidermolysis bullosa simplex with muscular dystrophy.

    Winter, Lilli; Türk, Matthias; Harter, Patrick N; Mittelbronn, Michel; Kornblum, Cornelia; Norwood, Fiona; Jungbluth, Heinz; Thiel, Christian T; Schlötzer-Schrehardt, Ursula; Schröder, Rolf

    2016-01-01

    Mutations of the human plectin gene (PLEC) on chromosome 8q24 cause autosomal recessive epidermolysis bullosa simplex with muscular dystrophy (EBS-MD). In the present study we analyzed the downstream effects of PLEC mutations on plectin protein expression and localization, the structure of the extrasarcomeric desmin cytoskeleton, protein aggregate formation and mitochondrial distribution in skeletal muscle tissue from three EBS-MD patients. PLEC gene analysis in a not previously reported 35-year-old EBS-MD patient with additional disease features of cardiomyopathy and malignant arrhythmias revealed novel compound heterozygous (p.(Phe755del) and p.(Lys1040Argfs*139)) mutations resulting in complete abolition of plectin protein expression. In contrast, the other two patients with different homozygous PLEC mutations showed preserved plectin protein expression with one only expressing rodless plectin variants, and the other markedly reduced protein levels. Analysis of skeletal muscle tissue from all three patients revealed severe disruption of the extrasarcomeric intermediate filament cytoskeleton, protein aggregates positive for desmin, syncoilin, and synemin, degenerative myofibrillar changes, and mitochondrial abnormalities comprising respiratory chain dysfunction and an altered organelle distribution and amount.Our study demonstrates that EBS-MD causing PLEC mutations universally result in a desmin protein aggregate myopathy phenotype despite marked differences in individual plectin protein expression patterns. Since plectin is the key cytolinker protein that regulates the structural and functional organization of desmin filaments, the defective anchorage and spacing of assembled desmin filaments is the key pathogenetic event that triggers the formation of desmin protein aggregates as well as secondary mitochondrial pathology. PMID:27121971

  20. Effect of additives on the purification of urease

    Yu, X.; Wang, J.; Ulrich, J.

    2015-12-01

    The effect of additives on the purification of proteins was investigated. The target protein studied here is the enzyme urease. Studies on the purification of urease from jack bean meal were carried out. 32% (v/v) acetone was utilized to extract urease from the jack bean meal. Further purification by crystallization with the addition of 2-mercaptoethanol and EDTA disodium salt dehydrate was carried out. It was found out that the presence of additives can affect the selectivity of the crystallization. Increases in both purity and yield of the urease after crystallization were observed in the presence of additives, which were proven using both SDS-PAGE and activity. Urease crystals with a yield of 69.9% and a purity of 85.1% were obtained in one crystallization step in the presence of additives. Furthermore, the effect of additives on the thermodynamics and kinetics of urease crystallization was studied.

  1. Biological effects of space-induced mutation on robinia pseudoacacia

    Dry seeds of Robinia pseudoacacia were carried by Shijian No.8 breeding satellite for mutagenesis and the biological effect of space-induced mutation was studied. The parameters of Robinia pseudoacacia such as plant height, stem base, branch number, knot spacing, length of thorn and chlorophyll content were analyzed, and, at the same time, the genetic diversity was tested by SSR marker. The results showed that the plant height and stem base of 2-year-old seedlings which derived from space mutagenesis were 22.0% and 24.1% lower than those of control, and 3-year-old seedlings were 13.1% and 22.4% lower than those of control, respectively. While the inhibiting effect of plant height became undermined in the following growth years. However, the inhibiting effect in stem base existed all the time,the length of thorn of branch and stem were 15.6% and 28.6% shorter than the control,respectively. Compared with the control,the variation of the length of thorn from stem was extremely significant. The variation of chlorophyll a content from space mutagenesis compared with control was not remarkable, while the total chlorophyll and chlorophyll b contents were 18.7% and 9.7% lower than those of control, respectively, and the difference between space mutagenesis and control was significant. While the chlorophyll a/b was 25.6% higher than that of control, but the difference was not significant. The coefficient of variation of the relative traits was increased by the space mutagenesis. The extensively population genome mutation after space-induction were not detected by SSR (Simple Sequence Repeats). (authors)

  2. Mutations Closer to the Active Site Improve the Promiscuous Aldolase Activity of 4-Oxalocrotonate Tautomerase More Effectively than Distant Mutations.

    Rahimi, Mehran; van der Meer, Jan-Ytzen; Geertsema, Edzard M; Poddar, Harshwardhan; Baas, Bert-Jan; Poelarends, Gerrit J

    2016-07-01

    The enzyme 4-oxalocrotonate tautomerase (4-OT), which catalyzes enol-keto tautomerization as part of a degradative pathway for aromatic hydrocarbons, promiscuously catalyzes various carbon-carbon bond-forming reactions. These include the aldol condensation of acetaldehyde with benzaldehyde to yield cinnamaldehyde. Here, we demonstrate that 4-OT can be engineered into a more efficient aldolase for this condensation reaction, with a >5000-fold improvement in catalytic efficiency (kcat /Km ) and a >10(7) -fold change in reaction specificity, by exploring small libraries in which only "hotspots" are varied. The hotspots were identified by systematic mutagenesis (covering each residue), followed by a screen for single mutations that give a strong improvement in the desired aldolase activity. All beneficial mutations were near the active site of 4-OT, thus underpinning the notion that new catalytic activities of a promiscuous enzyme are more effectively enhanced by mutations close to the active site. PMID:27238293

  3. Integrated genetic and epigenetic analysis of bladder cancer reveals an additive diagnostic value of FGFR3 mutations and hypermethylation events

    Serizawa, Reza R; Ralfkiaer, Ulrik; Steven, Kenneth;

    2011-01-01

    screened FGFR3, PIK3CA, TP53, HRAS, NRAS and KRAS for mutations and quantitatively assessed the methylation status of APC, ARF, DBC1, INK4A, RARB, RASSF1A, SFRP1, SFRP2, SFRP4, SFRP5 and WIF1 in a prospective series of tumor biopsies (N = 105) and urine samples (N = 113) from 118 bladder tumor patients. We...

  4. Pairwise-additive hydrophobic effect for alkanes in water

    Wu, Jianzhong; Prausnitz, John M.

    2008-01-01

    Pairwise additivity of the hydrophobic effect is indicated by reliable experimental Henry's constants for a large number of linear and branched low-molecular-weight alkanes in water. Pairwise additivity suggests that the hydrophobic effect is primarily a local phenomenon and that the hydrophobic interaction may be represented by a semiempirical force field. By representing the hydrophobic potential between two methane molecules as a linear function of the overlap volume of the hydration layer...

  5. Platelet hexosaminidase a enzyme assay effectively detects carriers missed by targeted DNA mutation analysis.

    Nakagawa, Sachiko; Zhan, Jie; Sun, Wei; Ferreira, Jose Carlos; Keiles, Steven; Hambuch, Tina; Kammesheidt, Anja; Mark, Brian L; Schneider, Adele; Gross, Susan; Schreiber-Agus, Nicole

    2012-01-01

    Biochemical testing of hexosaminidase A (HexA) enzyme activity has been available for decades and has the ability to detect almost all Tay-Sachs disease (TSD) carriers, irrespective of ethnic background. This is increasingly important, as the gene pool of those who identify as Ashkenazi Jewish is diversifying. Here we describe the analysis of a cohort of 4,325 individuals arising from large carrier screening programs and tested by the serum and/or platelet HexA enzyme assays and by targeted DNA mutation analysis. Our results continue to support the platelet assay as a highly effective method for TSD carrier screening, with a low inconclusive rate and the ability to detect possible disease-causing mutation carriers that would have been missed by targeted DNA mutation analysis. Sequence analysis performed on one such platelet assay carrier, who had one non-Ashkenazi Jewish parent, identified the amino acid change Thr259Ala (A775G). Based on crystallographic modeling, this change is predicted to be deleterious, as threonine 259 is positioned proximal to the HexA alpha subunit active site and helps to stabilize key residues therein. Accordingly, if individuals are screened for TSD in broad-based programs by targeted molecular testing alone, they must be made aware that there is a more sensitive and inexpensive test available that can identify additional carriers. Alternatively, the enzyme assays can be offered as a first tier test, especially when screening individuals of mixed or non-Jewish ancestry. PMID:23430931

  6. Pleiotropic Effect of tatC Mutation on Metabolism of Pathogen Yesinia enterocolitica

    2007-01-01

    Objective To analyze the impact of depletion of the twin arginine translocation (TAT) system on virulence and physiology of Yersinia enterocolitica for a better understanding of its pathogenicity. Methods We constructed a △tatC::SpRmutant of Yersinia enterocolitica by P1 phage mediated transduction using Escherichia coli K-12 △tatC::SpR strain as a donor. Results A P1-mediated genetic material transfer was found between the two species of enterobacteria, indicating a great potential of acquisition of antibiotic resistance in emergency of a new threatening pathogen by genetic material exchanges.Periplasmic trimethylamine N-oxidase reductase activity was detected in the wild type Y. enterocolitica strain and translocation of this enzyme was completely abolished by the △tatC::SpR mutation. In addition, the △tatC::SpR mutation showed a pleiotropic effect on the metabolism of Y. enterocolitica. However, the tat mutation did not seem to affect the mobility and virulence of Y.enterocolitica under the conditions used. Conclusion Unlike other pathogenic bacteria studied, the TAT system of Y.enterocolitica might play an important role in the pathogenic process, which is distinct from other pathogens, such as Pseudomonas aeruginosa and enterohemorrhagic E. coli O157:H7.

  7. The A431E mutation in PSEN1 causing Familial Alzheimer’s Disease originating in Jalisco State, Mexico: an additional fifteen families

    Murrell, Jill; Ghetti, Bernardino; Cochran, Elizabeth; Macias-Islas, Miguel Angel; Medina, Luis; Varpetian, Arousiak; Cummings, Jeffrey L.; Mendez, Mario F.; KAWAS, CLAUDIA; Chui, Helena; Ringman, John M.

    2006-01-01

    Nine families with autosomal dominant Alzheimer’s disease (AD), all of whom had the Ala431Glu substitution in the PSEN1 gene and came from Jalisco State in Mexico, have been previously reported. As they shared highly polymorphic flanking dinucleotide marker alleles, this strongly suggests that this mutation arose from a common founder. In the current letter, we expand this observation by describing an additional 15 independent families with the Ala431Glu substitution in the PSEN1 gene and con...

  8. Study on thermal effects & sulfurized additives, in lubricating greases

    Shah, Ami Atul

    Lithium Base grease constitutes about 50% of market. The greases are developed to be able to work in multiple working conditions and have longer working life. Greases with extreme pressure additives and anti-wear additives have been developed as a solution to many of the applications. These developed greases are tested under ASTM D2266 testing conditions to meet the requirements. The actual working conditions, although, differ than the real testing conditions. The loading, speed and temperature conditions can be more harsh, or fluctuating in nature. The cyclic nature of the parameters cannot be directly related to the test performance. For this purpose studies on the performance under spectrum loading, variable speed and fluctuating temperature must be performed. This study includes tests to understand the effect of thermal variation on some of the most commonly used grease additives that perform well under ASTM D2266 testing conditions. The studied additives include most widely used industrial extreme pressure additive MoS2. Performance of ZDDP which is trying to replace MoS2 in its industrial applications has also been studied. The tests cover study of extreme pressure, anti-wear and friction modifier additives to get a general idea on the effects of thermal variation in three areas. Sulphur is the most common extreme pressure additive. Sulphur based MoS 2 is extensively used grease additive. Study to understand the tribological performance of this additive through wear testing and SEM/EDX studies has been done. This performance is also studied for other metallic sulfides like WS2 and sulphur based organic compound. The aim is to study the importance of the type of bond that sulphur shares in its additive's structure on its performance. The MoS2 film formation is found to be on the basis of the FeS formation on the substrate and protection through sacrificial monolayer deposition of the MoS2 sheared structure. The free Mo then tends to oxidise. An attempt to

  9. MICO: A meta-tool for prediction of the effects of non-synonymous mutations

    Lee, Gilliean; Chen, Chin-Fu

    2014-01-01

    The Next Generation Sequencing (NGS) is a state-of-the-art technology that produces high throughput data with high resolution mutation information in the genome. Numerous methods with different efficiencies have been developed to predict mutational effects in the genome. The challenge is to present the results in a balanced manner for better biological insights and interpretation. Hence, we describe a meta-tool named Mutation Information Collector (MICO) for automatically querying and collect...

  10. Disparate Effects of Different Mutations in Plakoglobin on Cell Mechanical Behavior

    Huang, Hayden; Asimaki, Angeliki; Lo, Denise; McKenna, William; Saffitz, Jeffrey

    2008-01-01

    Mutations in genes encoding desmosomal proteins have been implicated in the pathogenesis of heart and skin diseases. This has led to the hypothesis that defective cell-cell adhesion is the underlying cause of injury in tissues that repeatedly bear high mechanical loads. In this study, we examined the effects of two different mutations in plakoglobin on cell migration, stiffness, and adhesion. One is a C-terminal mutation causing Naxos disease, a recessive syndrome of arrhythmogenic right vent...

  11. Effects of additives on glyphosate activity in purple nutsedge

    Effects of additives on 14 C-glyphosate penetration into purple nutsedge leaves were examined in the laboratory and efficacy of glyphosate for purple nutsedge control was studied in the greenhouse and field. The addition of (NH4)2 SO4 at 1.0% (v/v) + diesel oil at 1,0% (v/v) + Tendal at 1.0% (v/v) increased 14C-glyphosate penetration into nutsedge leaves more than the addition of either one alone. (NH4)2SO4 at 1.0% + diesel oil at 1.0% + Tendal at 0.12 or 0.25% increased the phytotoxicity of glyphosate at 0.5 and 0.75 kg, a.e./ha on nutsedge plants in the greenhouse but not in the field. Additives did not enhance glyphosate activity by reducing the number of nutsedae tubers. (author)

  12. Mutational effects of space flight on Zea mays seeds

    Mei, M.; Qiu, Y.; He, Y.; Bucker, H.; Yang, C. H.

    1994-01-01

    The growth and development of more than 500 Zea mays seeds flown on Long Duration Exposure Facility (LDEF) were studied. Somatic mutations, including white-yellow stripes on leaves, dwarfing, change of leaf sheath color or seedling color were observed in plants developed from these seeds. When the frequency of white-yellow formation was used as the endpoint and compared with data from ground based studies, the dose to which maize seeds might be exposed during the flight was estimated to be equivalent to 635 cGy of gamma rays. Seeds from one particular holder gave a high mutation frequency and a wide mutation spectrum. White-yellow stripes on leaves were also found in some of the inbred progenies from plants displayed somatic mutation. Electron microscopy studies showed that the damage of chloroplast development in the white-yellow stripe on leaves was similar between seeds flown on LDEF and that irradiated by accelerated heavy ions on ground.

  13. Ethnic differentials in health: the additional effect of ethnic density

    Feng, Zhixin; Vlachantoni, Athina; Falkingham, Jane; Evandrou, Maria

    2016-01-01

    It is well established that there are differentials in health among individuals of different Black and Minority Ethnic (BME) heritage. BME communities are unevenly concentrated across England and Wales. This paper examines the effect of residential density of one’s own ethnic group on physical health outcomes in England and Wales. In addition, it explores whether the effects of ethnic density on physical health outcomes are concealed by area deprivation, and whether individual economic depriv...

  14. Insights into enzyme point mutation effect by molecular simulation: phenylethylamine oxidation catalyzed by monoamine oxidase A.

    Oanca, Gabriel; Purg, Miha; Mavri, Janez; Shih, Jean C; Stare, Jernej

    2016-05-21

    The I335Y point mutation effect on the kinetics of phenylethylamine decomposition catalyzed by monoamine oxidase A was elucidated by means of molecular simulation. The established empirical valence bond methodology was used in conjunction with the free energy perturbation sampling technique and a classical force field representing the state of reactants and products. The methodology allows for the simulation of chemical reactions, in the present case the breaking of the α-C-H bond in a phenylethylamine substrate and the subsequent hydrogen transfer to the flavin cofactor, resulting in the formation of the N-H bond on flavin. The empirical parameters were calibrated against the experimental data for the simulated reaction in a wild type protein and then used for the calculation of the reaction free energy profile in the I335Y mutant. In very good agreement with the measured kinetic data, mutation increases the free energy barrier for the rate limiting step by slightly more than 1 kcal mol(-1) and consequently decreases the rate constant by about an order of magnitude. The magnitude of the computed effect slightly varies with simulation settings, but always remains in reasonable agreement with the experiment. Analysis of trajectories reveals a major change in the interaction between phenyl rings of the substrate and the neighboring Phe352 residue upon the I335Y mutation due to the increased local polarity, leading to an attenuated quadrupole interaction between the rings and destabilization of the transition state. Additionally, the increased local polarity in the mutant allows for a larger number of water molecules to be present near the active site, effectively shielding the catalytic effect of the enzyme and contributing to the increased barrier. PMID:27121693

  15. Effect of mutation and polyploidy breeding methods in tree cotton (Gossypium arboreum)

    An experiment was conducted during 1988 to understand the effect of mutation and ploy ploidy breeding methods in improving economically important characters of tree or desi cotton (Gossypium arboreum L.). It was determined by evaluating derivatives of M5 and C5 generation by the 2 methods. Polyploidy method proved more effective in improving halo length and seed index, whereas mutation breeding method in improving seed-cotton yield. No method proved effective in improving ginning out turn however, mutation method was slightly superior to polyploidy method. Adoption of polyploidy rather than mutation breeding method proved more effective for improving negatively correlation characters, i.e. ginning out turn with halo length and seed index. Magnitude of genetic variability was higher in the population derived by mutation breeding method, indicating better scope for further improvement. (author). 6 refs., 2 tabs

  16. Mutational effects of γ-rays and carbon ion beams on Arabidopsis seedlings

    Yoshihara, Ryouhei; Nozawa, Shigeki; Hase, Yoshihiro; Narumi, Issay; Hidema, Jun; Sakamoto, Ayako N

    2013-01-01

    To assess the mutational effects of radiation on vigorously proliferating plant tissue, the mutation spectrum was analyzed with Arabidopsis seedlings using the plasmid-rescue method. Transgenic plants containing the Escherichia coli rpsL gene were irradiated with γ-rays and carbon ion beams (320-MeV 12C6+), and mutations in the rpsL gene were analyzed. Mutant frequency increased significantly following irradiation by γ-rays, but not by 320-MeV 12C6+. Mutation spectra showed that both radiatio...

  17. Contamination effects of drilling fluid additives on cement slurry

    Youzhi Zheng

    2015-10-01

    Full Text Available During the cementation of deep wells, contamination at the contact surface between cement slurry and drilling fluid will present a technical challenge, which may threaten operation safety. To deal with the problem, lab tests and analysis were performed specifically on the compatibility of fluids during cementation in Sichuan and Chongqing gas fields. Impacts of commonly used additives for drilling fluids were determined on fluidity and thickening time of conventional cement slurry. Through the infrared spectrum analysis, SEM and XRD, infrared spectrum data of kalium polyacrylamide (KPAM and bio-viscosifier were obtained, together with infrared spectrum, SEM and XRD data of cement slurry with additives. Contamination mechanisms of the cement slurry by conventional additives for drilling fluid were reviewed. Test results show that both KPAM and bio-viscosifier are such high-molecular materials that the long chains in these materials may easily absorb cement particles in the slurry to form mixed network structures; as a result, cement particles were prone to agglomeration and eventually lost their pumpability. Finally, assessment of and testing methods for the contamination effects of drilling fluid additives on cement slurry were further improved to form standards and codes that may help solve the said problems. This study will provide technological supports for the preparation of drilling fluids with desirable properties prior to cementation, the selection of optimal drilling fluids additives, and the development of innovative drilling fluids additives.

  18. Large-Effect Beneficial Synonymous Mutations Mediate Rapid and Parallel Adaptation in a Bacterium.

    Agashe, Deepa; Sane, Mrudula; Phalnikar, Kruttika; Diwan, Gaurav D; Habibullah, Alefiyah; Martinez-Gomez, Norma Cecilia; Sahasrabuddhe, Vinaya; Polachek, William; Wang, Jue; Chubiz, Lon M; Marx, Christopher J

    2016-06-01

    Contrary to previous understanding, recent evidence indicates that synonymous codon changes may sometimes face strong selection. However, it remains difficult to generalize the nature, strength, and mechanism(s) of such selection. Previously, we showed that synonymous variants of a key enzyme-coding gene (fae) of Methylobacterium extorquens AM1 decreased enzyme production and reduced fitness dramatically. We now show that during laboratory evolution, these variants rapidly regained fitness via parallel yet variant-specific, highly beneficial point mutations in the N-terminal region of fae These mutations (including four synonymous mutations) had weak but consistently positive impacts on transcript levels, enzyme production, or enzyme activity. However, none of the proposed mechanisms (including internal ribosome pause sites or mRNA structure) predicted the fitness impact of evolved or additional, engineered point mutations. This study shows that synonymous mutations can be fixed through strong positive selection, but the mechanism for their benefit varies depending on the local sequence context. PMID:26908584

  19. Tin nanoparticles as an effective conductive additive in silicon anodes.

    Zhong, L; Beaudette, C; Guo, J; Bozhilov, K; Mangolini, L

    2016-01-01

    We have found that the addition of tin nanoparticles to a silicon-based anode provides dramatic improvements in performance in terms of both charge capacity and cycling stability. Using a simple procedure and off-the-shelf additives and precursors, we developed a structure in which the tin nanoparticles are segregated at the interface between the silicon-containing active layer and the solid electrolyte interface. Even a minor addition of tin, as small as ∼2% by weight, results in a significant decrease in the anode resistance, as confirmed by electrochemical impedance spectroscopy. This leads to a decrease in charge transfer resistance, which prevents the formation of electrically inactive "dead spots" in the anode structure and enables the effective participation of silicon in the lithiation reaction. PMID:27484849

  20. Tin nanoparticles as an effective conductive additive in silicon anodes

    Zhong, L.; Beaudette, C.; Guo, J.; Bozhilov, K.; Mangolini, L.

    2016-01-01

    We have found that the addition of tin nanoparticles to a silicon-based anode provides dramatic improvements in performance in terms of both charge capacity and cycling stability. Using a simple procedure and off-the-shelf additives and precursors, we developed a structure in which the tin nanoparticles are segregated at the interface between the silicon-containing active layer and the solid electrolyte interface. Even a minor addition of tin, as small as ∼2% by weight, results in a significant decrease in the anode resistance, as confirmed by electrochemical impedance spectroscopy. This leads to a decrease in charge transfer resistance, which prevents the formation of electrically inactive “dead spots” in the anode structure and enables the effective participation of silicon in the lithiation reaction. PMID:27484849

  1. Effects of small ionic amphiphilic additives on reverse microemulsion morphology

    Hopkins Hatzopoulos, Marios T; James, Craig; Rogers, Sarah E.; Grillo, Isabelle; Dowding, Peter J; Eastoe, Julian

    2014-01-01

    HypothesisInitial studies (Hopkins Hatzopoulos et al. (2013)) have shown that ionic hydrotropic additives can drive a sphere-to-cylinder (ellipsoid) transition in water-in-oil (w/o) microemulsions stabilized by the anionic surfactant Aerosol-OT; however the origins of this behaviour remained unclear. Here systematic effects of chemical structure are explored with a new set of hydrotropes, in terms of an aromatic versus a saturated cyclic hydrophobic group, and linear chain length of alkyl car...

  2. Sentinel and other mutational effects in offspring of cancer survivors

    To date, no agent has been documented to cause germ cell mutation in human beings, with the possible exception of radiation causing abnormal meiotic chromosomes in testes. For studies in humans, mutation epidemiologists prefer the cohort approach, starting with an exposed population and looking for mutations that may be expressed in offspring as variants in health, chromosomes, proteins, or nucleic acids. Currently patients with cancer are the cohort exposed to the largest doses of potential mutagens, i.e., radiotherapy and drugs. In 12 large studies with over 825 patients and 1573 pregnancies, 46 (4%) of 1240 liveborns had a major birth defect, a rate comparable to that in the general population. One of these was a classic sentinel phenotype, i.e., a new sporadic case of a dominant mendelian syndrome. In collaboration with 5 U.S. cancer registries, we interviewed a retrospective cohort of 2383 patients diagnosed with cancer under age 20 years, from 1945 through 1975. Records were sought to verify major genetic disease, defined as a cytogenetic or single gene disorder or 1 of 15 isolated birth defects. In 2308 offspring of survivors, 5 had a chromosomal syndrome, 11 had a single gene disorder, and 62 had at least one major malformation. Among 4722 offspring of sibling controls, the respective numbers were 7, 12, and 127, nonsignificant differences. 7% of the parents of the offspring with possibly new mutations received potentially mutagenic therapy, compared with 12% of parents of normal children. Since pregnancy in or by cancer survivors is still a rare event, future efforts to document germ cell mutation may be best studied through international cooperation coupled with diverse laboratory measures of mutation

  3. A recessive mutation in the APP gene with dominant-negative effect on amyloidogenesis.

    Di Fede, Giuseppe; Catania, Marcella; Morbin, Michela; Rossi, Giacomina; Suardi, Silvia; Mazzoleni, Giulia; Merlin, Marco; Giovagnoli, Anna Rita; Prioni, Sara; Erbetta, Alessandra; Falcone, Chiara; Gobbi, Marco; Colombo, Laura; Bastone, Antonio; Beeg, Marten; Manzoni, Claudia; Francescucci, Bruna; Spagnoli, Alberto; Cantù, Laura; Del Favero, Elena; Levy, Efrat; Salmona, Mario; Tagliavini, Fabrizio

    2009-03-13

    beta-Amyloid precursor protein (APP) mutations cause familial Alzheimer's disease with nearly complete penetrance. We found an APP mutation [alanine-673-->valine-673 (A673V)] that causes disease only in the homozygous state, whereas heterozygous carriers were unaffected, consistent with a recessive Mendelian trait of inheritance. The A673V mutation affected APP processing, resulting in enhanced beta-amyloid (Abeta) production and formation of amyloid fibrils in vitro. Co-incubation of mutated and wild-type peptides conferred instability on Abeta aggregates and inhibited amyloidogenesis and neurotoxicity. The highly amyloidogenic effect of the A673V mutation in the homozygous state and its anti-amyloidogenic effect in the heterozygous state account for the autosomal recessive pattern of inheritance and have implications for genetic screening and the potential treatment of Alzheimer's disease. PMID:19286555

  4. A study on photoreceptor by using the effect of additives

    We have been studied photosensitization mechanism's additive effect, of perylene 3,4,9,10-tetracarboxyl-diimide and X-phthalocyanine (charge generation materials), using the photochemical and photoelectrochemical approach. It was found that the photoreceptor on the excited state reacts with metal oxide, which creates the charge transfer on the interface of SnO2/electrolyte. In the electrode (X5P1) made of five X-phthalocyanine and single perylene 3,4,9,10-tetracarboxyldiimide layers, the cathodic photocurrent of X-phthalocyanine in the 400-600 nm region was increased by the addition of perylene 3,4,9,10-tetracarboxyldiimide. The maximum wavelength of fluorescence of perylene 3,4,9,10-tetracarboxyldiimide showed no dependence on the temperature. The addition of 4-dibenzylamino-2-methylbenzaldehyde diphenylhydrazone known as charge transport material was represented as decreasing photocurrent for X-phthalocyanine and perylene 3,4,9,10-tetracarboxyldiimide, respectively. In the electrode (X1P1) made of single X-phthalocyanine and single perylene 3,4,9,10-tetracarboxyldiimide layers, an anodic photocurrent of about 10.5 nA was generated by addition of hydroquinone at 550 nm. And the characteristic of photoinduced discharge was shown to decrease by a factor 5 and the speed of dark decay was increased by a factor of 1.2

  5. Effect of additives on physicochemical properties in amorphous starch matrices.

    Liang, Jun; Wang, Simon; Ludescher, Richard D

    2015-03-15

    The effect of the addition of non-reducing sugars or methylcellulose on the matrix physical properties and rate of non-enzymatic browning (NBR) between exogenous glucose+lysine in a starch-based glassy matrix were studied, using the methods of luminescence and FTIR. Amorphous starch-based matrices were formulated by rapidly dehydrating potato starch gel mixed with additives at weight ratios of 7:93 (additive:starch). Data on the phosphorescence emission energy and lifetime from erythrosin B dispersed in the matrices indicated that sugars decreased starch matrix mobility in a Tg-dependent manner, except for trehalose that interacted with starch in a unique mode, while methylcellulose, the additive with the highest Tg, increased the molecular mobility. Using FTIR, we found that methylcellulose decreased the strength of hydrogen bond network and sugars enhanced the hydrogen bond strength in the order: trehalose>maltitol>sucrose. Comparing those changes with the rate of NBR between exogenous glucose+lysine, we suggest that NBR rates are primarily influenced by matrix mobility, which is modulated by the hydrogen bond network, and interactions among components. PMID:25308673

  6. Effect of radiation resistance additives for insulation materials

    For the electric wires and cables used in radiation environment such as nuclear power stations and fuel reprocessing facilities, the properties of excellent radiation resistance are required. For these insulators and sheath materials, ethylene propylene rubber, polyethylene and other polymers have been used, but it cannot be said that they always have good radiation resistance. However, it has been well known that radiation resistance can be improved with small amount of additives, and heat resistance and burning retarding property as well as radiation resistance are given to the insulators of wires and cables for nuclear facilities by mixing various additives. In this research, the measuring method for quantitatively determining the effect of Anti-rad (radiation resistant additive) was examined. Through the measurement of gel fraction, radical formation and decomposed gas generation, the effect of Anti-rad protecting polymers from radiation deterioration was examined from the viewpoint of chemical reaction. The experimental method and the results are reported. The radiation energy for cutting C-H coupling is polymers is dispersed by Anti-rad, and the probability of cutting is lowered. Anti-rad catches and extinguishes radicals that start oxidation reaction. (K.I.)

  7. Evaluating the Effects of Additives on Drilling Fluid Characteristics

    Uche OSOKOGWU*

    2014-06-01

    Full Text Available Drilling fluid plays a vital role in hole cleaning, suspension of cuttings, prevent caving, and ensure the tightness of the well wall. Moreover, they also help in cooling and lubricating the drilling tool, transfer the hydraulic power and carry information about the nature of the drilled formation by raising the cuttings from the bottom to the surface, using a simple mixture of water and clays, to complex mixtures of various specific organic and inorganic products as additives. These additives improve fluid rheological properties and filtration capability, allowing bits to penetrate heterogeneous geological formations. Two potassium Chloride polymers were formulated to test the effect of varying concentration of additives on the drilling fluid characteristic for water base mud. From the experimental results of formulation 1and 2, rheological properties shows that the plastic viscosities are 18 and 8Cp and yield point are 32 and 8 lb/100ft2 respectively. Also the mud weights are 8.4 and 8.3ppg, fluid loss, 11and 13 mls, and pH are 12.7and 12.5 respectively. Two oil base muds were also formulated to test the effect of additives on drilling fluid characteristic at varying concentration. From the experimental results, the rheological properties show that the plastic viscosities are 19and 13Cp and yield point are 21 and 10lb/100ft2 respectively. Also the mud weights are 9.5 and 9.0 ppg, fluid loss, 6 and 10 mls, and pH are 10.5and 9.7 respectively. Electrical stability which is the increase in voltage across a probe until the emulsion breaks and a current is established were also obtained as 400 and 340v in the oil base mud. It will vary with the amount of water - the more water generally the lower the stability; as the emulsion stabilizes the electrical stability increases..

  8. Accurate Measurement of the Effects of All Amino-Acid Mutations on Influenza Hemagglutinin

    Doud, Michael B.; Bloom, Jesse D.

    2016-01-01

    Influenza genes evolve mostly via point mutations, and so knowing the effect of every amino-acid mutation provides information about evolutionary paths available to the virus. We and others have combined high-throughput mutagenesis with deep sequencing to estimate the effects of large numbers of mutations to influenza genes. However, these measurements have suffered from substantial experimental noise due to a variety of technical problems, the most prominent of which is bottlenecking during the generation of mutant viruses from plasmids. Here we describe advances that ameliorate these problems, enabling us to measure with greatly improved accuracy and reproducibility the effects of all amino-acid mutations to an H1 influenza hemagglutinin on viral replication in cell culture. The largest improvements come from using a helper virus to reduce bottlenecks when generating viruses from plasmids. Our measurements confirm at much higher resolution the results of previous studies suggesting that antigenic sites on the globular head of hemagglutinin are highly tolerant of mutations. We also show that other regions of hemagglutinin—including the stalk epitopes targeted by broadly neutralizing antibodies—have a much lower inherent capacity to tolerate point mutations. The ability to accurately measure the effects of all influenza mutations should enhance efforts to understand and predict viral evolution. PMID:27271655

  9. Effect of Residue Mutation on the Electrostatic Potential in EcCIC

    ZOU Xianwu; DONG Shuxiang; WANG Xiaoqing; HUANG Shengyou

    2007-01-01

    The effect of mutation of strongly conserved porelining residues in the chloride channel EcClC on the electrostatic potential and binding free energy of the chloride ion was studied using explicit protein-membrane structures. Electrostatic potential distribution and binding free energy of the chloride ion at different binding sites in the wild-type and mutated EcClC were calculated with APBS. The potential data reveal that the electrostatic potential around the selectivity filter, especially around the site Sext and Scen becomes more negative as the residue R147 was mutated to C147. The electrostatic binding free energy shows that the binding free energy of the chloride ion at all binding sites becomes more positive as R147 was mutated. It follows that mutation of R147 decreases ion stabilization at binding sites and affects channel's gating.

  10. Additive effects of acetic acid upon hydrothermal reaction of amylopectin

    It is well known that over 0.8 kg kg−1 of starch is consisted of amylopectin (AP). In this study, production of glucose for raw material of ethanol by hydrothermal reaction of AP as one of the model compound of food is discussed. Further, additive effects of acetic acid upon hydrothermal reactions of AP are also investigated. During hydrothermal reaction of AP, production of glucose occurred above 453 K, and the glucose yield increased to 0.48 kg kg−1 at 473 K. Upon hydrothermal reaction of AP at 473 K, prolongation of the holding time was not effective for the increase of the glucose yield. Upon hydrothermal reaction of AP at 473 K for 0 s, the glucose yield increased significantly by addition between 0.26 mol L−1 and 0.52 mol L−1 of acetic acid. However, the glucose yield decreased and the yield of the other constituents increased with the increases of concentration of acetic acid from 0.65 mol L−1 to 3.33 mol L−1. It was considered that hydrolysis of AP to yield glucose was enhanced due to the increase of the amount of proton derived from acetic acid during hydrothermal reaction with 0.52 mol L−1 of acetic acid. -- Highlights: ► Glucose production by hydrothermal reaction of amylopectin (AP) at 473 K. ► Glucose yield increased to 0.48 kg kg-1 at 473 K. ► Prolongation of holding time was not effective for glucose yield. ► Glucose yield increased significantly by acetic acid (0.26–0.52 mol L-1) addition. ► Hydrolysis of AP to glucose was enhanced due to increase of proton from acetic acid.

  11. Mutations of Vasopressin Receptor 2 Including Novel L312S Have Differential Effects on Trafficking.

    Tiulpakov, Anatoly; White, Carl W; Abhayawardana, Rekhati S; See, Heng B; Chan, Audrey S; Seeber, Ruth M; Heng, Julian I; Dedov, Ivan; Pavlos, Nathan J; Pfleger, Kevin D G

    2016-08-01

    Nephrogenic syndrome of inappropriate antidiuresis (NSIAD) is a genetic disease first described in 2 unrelated male infants with severe symptomatic hyponatremia. Despite undetectable arginine vasopressin levels, patients have inappropriately concentrated urine resulting in hyponatremia, hypoosmolality, and natriuresis. Here, we describe and functionally characterize a novel vasopressin type 2 receptor (V2R) gain-of-function mutation. An L312S substitution in the seventh transmembrane domain was identified in a boy presenting with water-induced hyponatremic seizures at the age of 5.8 years. We show that, compared with wild-type V2R, the L312S mutation results in the constitutive production of cAMP, indicative of the gain-of-function NSIAD profile. Interestingly, like the previously described F229V and I130N NSIAD-causing mutants, this appears to both occur in the absence of notable constitutive β-arrestin2 recruitment and can be reduced by the inverse agonist Tolvaptan. In addition, to understand the effect of various V2R substitutions on the full receptor "life-cycle," we have used and further developed a bioluminescence resonance energy transfer intracellular localization assay using multiple localization markers validated with confocal microscopy. This allowed us to characterize differences in the constitutive and ligand-induced localization and trafficking profiles of the novel L312S mutation as well as for previously described V2R gain-of-function mutants (NSIAD; R137C and R137L), loss-of-function mutants (nephrogenic diabetes insipidus; R137H, R181C, and M311V), and a putative silent V266A V2R polymorphism. In doing so, we describe differences in trafficking between unique V2R substitutions, even at the same amino acid position, therefore highlighting the value of full and thorough characterization of receptor function beyond simple signaling pathway analysis. PMID:27355191

  12. Microsatellite instability and BRAF mutation in colorectal cancer: clinicopathological characteristics and effects on survival

    Sebnem Batur

    2016-04-01

    Full Text Available Prognostic significance of microsatellite instability (MSI status and B-type Raf proto-oncogene (BRAF mutation in colorectal cancer is controversial. The aim of this study was to examine the clinical and pathological characteristics associated with microsatellite stability and the effect of MSI and BRAF mutation on the survival of patients with colorectal cancer. The study included 145 colorectal cancer cases. All the patients were examined for DNA mismatch repair (MMR proteins with an immunohistochemical method. Molecular assessment of microsatellite instability was available in a subset of 41 patients. In addition, BRAF mutation analysis was performed in 30 cases. Immunohistochemically, MMR deficiency was present in 28 (19.3% patients. Female gender (p=0.001, lesion size ≥ 5 cm (p=0.013, Crohn like response (p=0.035, and right-sided localization (p<0.001 were significantly more frequent among MMR deficient patients. The overall survival was 44.1±5.1 months (95% CI, 33.7-54.4. Multivariate analyses identified only high tumor grade as an independent predictor of poor overall survival: OR, 6.7 (95% CI 2.1-21.7, p=0.002. In the subset of patients with available BRAF assessment (n=30, a negative BRAF status was associated with better survival when compared to a positive BRAF status (36.7±2.1 vs. 34.1±7.2 months, p=0.048. The sensitivity and specificity of the immunohistochemical method in predicting positive MSI status, with the molecular method as a reference, were 85.7% (95% CI: 56.2%-97.5% and 88.9% (95% CI: 69.7%-97.1%, respectively. BRAF appears to be a significant predictor of a worse outcome in patients with colorectal cancer. Further studies with a large spectrum of clinical and biological variables are warranted.

  13. The effects of extremely low frequency magnetic fields on mutation induction in mice

    Highlights: • The effects of 50 Hz magnetic fields on mutation induction in mice were analyzed. • The frequency of ESTR mutation was established in sperm and blood. • Exposure to 10–300 μT for 2 and 15 h did not result in mutation induction. • Mutagenic effects of 50 Hz magnetic fields are likely to be negligible. - Abstract: The growing human exposure to extremely low frequency (ELF) magnetic fields has raised a considerable concern regarding their genotoxic effects. The aim of this study was to evaluate the in vivo effects of ELF magnetic fields irradiation on mutation induction in the germline and somatic tissues of male mice. Seven week old BALB/c × CBA/Ca F1 hybrid males were exposed to 10, 100 or 300 μT of 50 Hz magnetic fields for 2 or 15 h. Using single-molecule PCR, the frequency of mutation at the mouse Expanded Simple Tandem Repeat (ESTR) locus Ms6-hm was established in sperm and blood samples of exposed and matched sham-treated males. ESTR mutation frequency was also established in sperm and blood samples taken from male mice exposed to 1 Gy of acute X-rays. The frequency of ESTR mutation in DNA samples extracted from blood of mice exposed to magnetic fields did not significantly differ from that in sham-treated controls. However, there was a marginally significant increase in mutation frequency in sperm but this was not dose-dependent. In contrast, acute exposure X-rays led to significant increases in mutation frequency in sperm and blood of exposed males. The results of our study suggest that, within the range of doses analyzed here, the in vivo mutagenic effects of ELF magnetic fields are likely to be minor if not negligible

  14. The effects of extremely low frequency magnetic fields on mutation induction in mice

    Wilson, James W. [Department of Genetics, University of Leicester, Leicester LE1 7RH (United Kingdom); Haines, Jackie; Sienkiewicz, Zenon [Centre for Radiation, Chemical and Environmental Hazards, Public Health England, Chilton, Didcot, Oxfordshire OX11 0RQ (United Kingdom); Dubrova, Yuri E., E-mail: yed2@le.ac.uk [Department of Genetics, University of Leicester, Leicester LE1 7RH (United Kingdom)

    2015-03-15

    Highlights: • The effects of 50 Hz magnetic fields on mutation induction in mice were analyzed. • The frequency of ESTR mutation was established in sperm and blood. • Exposure to 10–300 μT for 2 and 15 h did not result in mutation induction. • Mutagenic effects of 50 Hz magnetic fields are likely to be negligible. - Abstract: The growing human exposure to extremely low frequency (ELF) magnetic fields has raised a considerable concern regarding their genotoxic effects. The aim of this study was to evaluate the in vivo effects of ELF magnetic fields irradiation on mutation induction in the germline and somatic tissues of male mice. Seven week old BALB/c × CBA/Ca F{sub 1} hybrid males were exposed to 10, 100 or 300 μT of 50 Hz magnetic fields for 2 or 15 h. Using single-molecule PCR, the frequency of mutation at the mouse Expanded Simple Tandem Repeat (ESTR) locus Ms6-hm was established in sperm and blood samples of exposed and matched sham-treated males. ESTR mutation frequency was also established in sperm and blood samples taken from male mice exposed to 1 Gy of acute X-rays. The frequency of ESTR mutation in DNA samples extracted from blood of mice exposed to magnetic fields did not significantly differ from that in sham-treated controls. However, there was a marginally significant increase in mutation frequency in sperm but this was not dose-dependent. In contrast, acute exposure X-rays led to significant increases in mutation frequency in sperm and blood of exposed males. The results of our study suggest that, within the range of doses analyzed here, the in vivo mutagenic effects of ELF magnetic fields are likely to be minor if not negligible.

  15. EFFECT OF THE ANTIMUTAGENS VANILLIN AND CINNAMALDEHYDE ON THE SPONTANEOUS MUTATION SPECTRA OF SALMONELLA TA104

    Effect of the Antimutagens Vanillin and Cinnamaldehyde on the / Spontaneous Mutation Spectra of Salmonella TAlO4 Vanillin (VAN) and cinnamaldehyde (CIN) are dietary antimutagens that, when added to assay plates, reduced the spontaneous mutant frequency in Salmonella typhi...

  16. Priming effects in Haplic Luvisol after different substrate additions

    Bogomolova, I.; Blagodatskaya, E.; Blagodatsky, S.; Kuzyakov, Y.

    2009-04-01

    Although soils contain considerable amounts of soil organic carbon (SOC), most of it is not easily available for microorganisms. Addition of various substrates to soil (for example, plant residues, root exudates) may affect SOC mineralization. The addition of mineral nutrients, especially N, may also affect C turnover and so change the mineralization rate of SOC. Such short-term changes in mineralization of organic substance of soil were termed as "priming-effects" (Bingemann et al., 1953). Priming effect leads to additional mineralization of SOC (van Elsas and van Overbeek, 1993). It has been shown that not only plant residues induce priming effects (Sauerbeck, 1966; Stemmer et al., 1999; Bell et al., 2003), but also easily available substrates such as sugars or amino acids, which are present in soil solutions and root exudates (Vasconcellos, 1994; Shen and Bartha, 1997; Hamer and Marschner, 2002). Since easily available substrates may not only accelerate SOC mineralization, but also may retard it, Kuzyakov et al. (2000) differentiated between positive and negative priming effects. It is not clear until now, how long priming effects persists in soil after substrate addition, and if they are induced every time when a substrate becomes available in soil. So, the aim of this study was to evaluate effects of glucose and plant residues on SOM decomposition, and influence of glucose on plant residues decomposition in soil. The experimental layout was designed as two factor experiment: 1) plant residues and 2) available substrate amendment. Maize shoot residues (50 mg added to 5 g soil) were 14C labeled (9•104 DPM per 5 g soil). Soil without of any plant residues served as a control for this treatment. Two levels of D (+) glucose as easily available substrates were added after three months of pre-incubation of soil samples with maize residues: 0.009 mg glucose C g-1 soil and 0.225 mg glucose C g-1 soil. The glucose was uniformly labelled with 14C (2.37•104 DPM per 5

  17. Effect of the G375C and G346E achondroplasia mutations on FGFR3 activation.

    Lijuan He

    Full Text Available Two mutations in FGFR3, G380R and G375C are known to cause achondroplasia, the most common form of human dwarfism. The G380R mutation accounts for 98% of the achondroplasia cases, and thus has been studied extensively. Here we study the effect of the G375C mutation on the phosphorylation and the cross-linking propensity of full-length FGFR3 in HEK 293 cells, and we compare the results to previously published results for the G380R mutant. We observe identical behavior of the two achondroplasia mutants in these experiments, a finding which supports a direct link between the severity of dwarfism phenotypes and the level and mechanism of FGFR3 over-activation. The mutations do not increase the cross-linking propensity of FGFR3, contrary to previous expectations that the achondroplasia mutations stabilize the FGFR3 dimers. Instead, the phosphorylation efficiency within un-liganded FGFR3 dimers is increased, and this increase is likely the underlying cause for pathogenesis in achondroplasia. We further investigate the G346E mutation, which has been reported to cause achondroplasia in one case. We find that this mutation does not increase FGFR3 phosphorylation and decreases FGFR3 cross-linking propensity, a finding which raises questions whether this mutation is indeed a genetic cause for human dwarfism.

  18. Parental source effect of inherited mutations in the dystrophin gene of mice and men

    Kress, W.; Grimm, T.; Mueller, C.R. [Institute of Human Genetics, Wuerburg (Germany); Bittner, R. [Institute of Anatomy, Wein (Australia)

    1994-09-01

    Skewed X-inactivation has been suspected the genetic cause for some manifesting female carriers of BMD and DMD. To test whether a parental source effect on the protein expression of the dystrophin gene exists, we have set up backcrosses of mdx mice to wild type strains, enabling us to study the effect of the well-defined origin of the mutation on the dystrophin expression. In skeletal muscle sections the immunohistological staining patterns of dystrophin antibodies were showing a significant difference in the proportion of dystrophin positive versus negative fibers, suggesting a lower expression of paternally inherited mdx mutations. These data are in concordance with the pyruvate kinase (PK) levels in the serum: PK levels were much higher when the mutation was of maternal origin as compared to PK levels in paternally derived mutations. In order to test this {open_quotes}paternal source effect{close_quotes} in humans, we checked obligatory carriers of Becker muscular dystrophy (BMD) for the origin of their mutations. Creatin kinase (CK) levels in 21 carriers with maternally derived mutations were compared to CK values from 8 heterozygotes with mutations of paternal origin: CK (mat) = 140.3 IU/1 versus CK (pat) = 48.6 IU/I. The difference is statistically significant at the 5% level. These observations suggest either a differential X-inactivation or an imprinting of the dystrophin gene in mice and men.

  19. The influence of oil additives on the effectiveness of herbicides

    Andrzej Chwedoruk

    2013-12-01

    Full Text Available The possibility to decrease herbicide doses without reducing their weed controlling effectiveness was investigated in two microplots and one field experiment. The following herbicides were used: atrazine, mixture of atrazine with terbutrine, MCPA + MCPP, MCPA + dikamba, desmedipham and phenmedipham (Betanal 31, 32 or 37. They were combined with one or several of the following adjuvants: parafinic oil, refuse product of rape oil rafination, oil mixture from the Institute of Organic Chemistry Industry (IPO-Warsaw, surfactant Rokafenol N-1O, mineral oil Nr 8 (Aviol. It was shown that the doses of herbicides could be lowered by 30-50% without loosing their phytotoxic effect on weeds due to addition of adjuvants. The mineral oil 8 was very active in a mixture with Betanal 37 and was completly non toxic toward sugar beets. The oil mixture from IPO and Rokafenol N-10 were very active in mixtures with atrazine or atraizine with terbutrine.

  20. MITF mutations associated with pigment deficiency syndromes and melanoma have different effects on protein function.

    Grill, Christine; Bergsteinsdóttir, Kristín; Ogmundsdóttir, Margrét H; Pogenberg, Vivian; Schepsky, Alexander; Wilmanns, Matthias; Pingault, Veronique; Steingrímsson, Eiríkur

    2013-11-01

    The basic-helix-loop-helix-leucine zipper (bHLHZip) protein MITF (microphthalmia-associated transcription factor) is a master regulator of melanocyte development. Mutations in the MITF have been found in patients with the dominantly inherited hypopigmentation and deafness syndromes Waardenburg syndrome type 2A (WS2A) and Tietz syndrome (TS). Additionally, both somatic and germline mutations have been found in MITF in melanoma patients. Here, we characterize the DNA-binding and transcription activation properties of 24 MITF mutations found in WS2A, TS and melanoma patients. We show that most of the WS2A and TS mutations fail to bind DNA and activate expression from melanocyte-specific promoters. Some of the mutations, especially R203K and S298P, exhibit normal activity and may represent neutral variants. Mutations found in melanomas showed normal DNA-binding and minor variations in transcription activation properties; some showed increased potential to form colonies. Our results provide molecular insights into how mutations in a single gene can lead to such different phenotypes. PMID:23787126

  1. Differential effects of CSF-1R D802V and KIT D816V homologous mutations on receptor tertiary structure and allosteric communication.

    Priscila Da Silva Figueiredo Celestino Gomes

    Full Text Available The colony stimulating factor-1 receptor (CSF-1R and the stem cell factor receptor KIT, type III receptor tyrosine kinases (RTKs, are important mediators of signal transduction. The normal functions of these receptors can be compromised by gain-of-function mutations associated with different physiopatological impacts. Whereas KIT D816V/H mutation is a well-characterized oncogenic event and principal cause of systemic mastocytosis, the homologous CSF-1R D802V has not been identified in human cancers. The KIT D816V oncogenic mutation triggers resistance to the RTK inhibitor Imatinib used as first line treatment against chronic myeloid leukemia and gastrointestinal tumors. CSF-1R is also sensitive to Imatinib and this sensitivity is altered by mutation D802V. Previous in silico characterization of the D816V mutation in KIT evidenced that the mutation caused a structure reorganization of the juxtamembrane region (JMR and facilitated its departure from the kinase domain (KD. In this study, we showed that the equivalent CSF-1R D802V mutation does not promote such structural effects on the JMR despite of a reduction on some key H-bonds interactions controlling the JMR binding to the KD. In addition, this mutation disrupts the allosteric communication between two essential regulatory fragments of the receptors, the JMR and the A-loop. Nevertheless, the mutation-induced shift towards an active conformation observed in KIT D816V is not observed in CSF-1R D802V. The distinct impact of equivalent mutation in two homologous RTKs could be associated with the sequence difference between both receptors in the native form, particularly in the JMR region. A local mutation-induced perturbation on the A-loop structure observed in both receptors indicates the stabilization of an inactive non-inhibited form, which Imatinib cannot bind.

  2. Eddy damping effect of additional conductors in superconducting levitation systems

    Jiang, Zhao-Fei; Gou, Xiao-Fan

    2015-12-01

    Passive superconducting levitation systems consisting of a high temperature superconductor (HTSC) and a permanent magnet (PM) have demonstrated several fascinating applications such as the maglev system, flywheel energy storage. Generally, for the HTSC-PM levitation system, the HTSC with higher critical current density Jc can obtain larger magnetic force to make the PM levitate over the HTSC (or suspended below the HTSC), however, the process of the vibration of the levitated PM, provides very limited inherent damping (essentially hysteresis). To improve the dynamic stability of the levitated PM, eddy damping of additional conductors can be considered as the most simple and effective approach. In this article, for the HTSC-PM levitation system with an additional copper damper attached to the HTSC, we numerically and comprehensively investigated the damping coefficient c, damping ratio, Joule heating of the copper damper, and the vibration frequency of the PM as well. Furthermore, we comparatively studied four different arrangements of the copper damper, on the comprehensive analyzed the damping effect, efficiency (defined by c/VCu, in which VCu is the volume of the damper) and Joule heating, and finally presented the most advisable arrangement.

  3. Probing the "additive effect" in the proline and proline hydroxamic acid catalyzed asymmetric addition of nitroalkanes to cyclic enones.

    Hanessian, Stephen; Govindan, Subramaniyan; Warrier, Jayakumar S

    2005-11-01

    The effect of chirality and steric bulk of 2,5-disubstituted piperazines as additives in the conjugate addition of 2-nitropropane to cyclohexenone, catalyzed by l-proline, was investigated. Neither chirality nor steric bulk affects the enantioselectivity of addition, which gives 86-93% ee in the presence of achiral and chiral nonracemic 2,5-disubstituted piperazines. Proline hydroxamic acid is shown for the first time to be an effective organocatalyst in the same Michael reaction. PMID:16189834

  4. Thermal processing of EVA encapsulants and effects of formulation additives

    Pern, F.J.; Glick, S.H. [National Renewable Energy Lab., Golden, CO (United States)

    1996-05-01

    The authors investigated the in-situ processing temperatures and effects of various formulation additives on the formation of ultraviolet (UV) excitable chromophores, in the thermal lamination and curing of ethylene-vinyl acetate (EVA) encapsulants. A programmable, microprocessor-controlled, double-bag vacuum laminator was used to study two commercial as formulated EVA films, A9918P and 15295P, and solution-cast films of Elvaxrm (EVX) impregnated with various curing agents and antioxidants. The results show that the actual measured temperatures of EVA lagged significantly behind the programmed profiles for the heating elements and were affected by the total thermal mass loaded inside the laminator chamber. The antioxidant Naugard P{trademark}, used in the two commercial EVA formulations, greatly enhances the formation of UV-excitable, short chromophores upon curing, whereas other tested antioxidants show little effect. A new curing agent chosen specifically for the EVA formulation modification produces little or no effect on chromophore formation, no bubbling problems in the glass/EVX/glass laminates, and a gel content of {approximately}80% when cured at programmed 155{degrees}C for 4 min. Also demonstrated is the greater discoloring effect with higher concentrations of curing-generated chromophores.

  5. Effect of the G375C and G346E Achondroplasia Mutations on FGFR3 Activation

    He, Lijuan; Serrano, Christopher; Niphadkar, Nitish; Shobnam, Nadia; Hristova, Kalina

    2012-01-01

    Two mutations in FGFR3, G380R and G375C are known to cause achondroplasia, the most common form of human dwarfism. The G380R mutation accounts for 98% of the achondroplasia cases, and thus has been studied extensively. Here we study the effect of the G375C mutation on the phosphorylation and the cross-linking propensity of full-length FGFR3 in HEK 293 cells, and we compare the results to previously published results for the G380R mutant. We observe identical behavior of the two achondroplasia...

  6. Mortar cohesión. The effect of additives

    Castro, J. H.

    1975-12-01

    Full Text Available This study was concerned with the hydration of clinker compounds in the presence of different additives; it appeared that accelerating additives, such as calcium chloride and silicic acid, produce longer fibers of tobermorite, whereas inhibitors, such as sugar, produce shorter fibers of tobermorite. This same effect was observed in the hydration of anhydrite, in which large crystals of gypsum were produced in the presence of sodium sulphate. So the cohesion in mortars of cement and anhydrite is explained in terms of the role of fibers.Se estudia la hidratación del clínker en presencia de diferentes aditivos encontrándose que los aceleradores, como el cloruro cálcico y el ácido salicílico, producen tobermorita de fibra larga y los inhibidores, como el azúcar, tobermorita de fibra corta. Este mismo efecto se encuentra en la anhidrita, produciéndose cristales de yeso largo, en presencia del sulfato de sodio, y cristales cortos en ausencia del catalizador. La cohesión de un mortero depende luego del largo de sus fibras. Así la cohesión de los morteros de cemento y anhidrita se explican en función del rol de la fibra.

  7. Effect of chemical additives on flow characteristics of coal slurries

    E.S. Mosa; A.-H. M. Saleh; T.A. Taha; A.M. El-Molla [Al-Azhar University, Cairo (Egypt). Mining & Petroleum Engineering Department

    2008-07-01

    In the present paper, the effect of chemical additives or reagents on rheological characteristics of coal water slurry (CWS) was investigated. The power-law model was applied to determine the non-Newtonian properties of coal slurries. Three types of dispersants namely, sulphonic acid, sodium tripolyphosphate and sodium carbonate were studied and tested at different concentrations ranging from 0.5 to 1.5% by weight from total solids. Sodium salt of carboxymethyl cellulose (Na-CMC) and xanthan gum were tested as stabilizers at concentrations in the range of 0.05 to 0.25% by weight from total solids. It was found that apparent viscosity and flow properties of CWS are sensitive to the use of chemical additives (dispersants and stabilizers). Among studied dispersing agents, sulphonic acid recorded the best performance in modification and reducing CWS viscosity. The best dosage of all tested dispersants was found to be 0.75% by wt of solids. With regard to studied stabilizers, Na-CMC recorded better performance than xanthan gum. The best dosage of investigated stabilizers was found to be as 0.1 % by wt. from total solids. 13 refs., 9 figs., 1 tab.

  8. Effect of different additives on the properties of lithium alanate

    2008-01-01

    LiAlH4 doped with Ni and Ce(SO4)2 additives and the effect of doping on temperature and hydrogen release were studied by pressure-content-temperature (PCT) experiment and X-ray diffraction (XRD) analysis.It is indicated that doping with Ni induces a significant decrease in temperature in the first step and LiAlH4 doped with 1mol% Ni presents the most absorption of hydrogen.Doping with Ce(SO4)2 also causes a marked decrease,while the amount of hydrogen release changes only slightly.The results from X-ray diffraction analysis show that doping does not cause any structural change; Ni and Ce-containing phases are not observed at room temperature or even at 250℃.

  9. Dolomite addition effects on the thermal expansion of ceramic tiles

    The thermal expansion of ceramic tiles is of greater importance in engineering applications because the ceramics are relatively brittle and cannot tolerate large internal strain imposed by thermal expansion. When ceramic bodies are produced for glazed ties the compatibility of this property of the components should be considered to avoid damage in the final products. Carbonates are an important constituent of ceramic wall-title bodies and its presence in formulations and the reactions that occur between them and other components modify body properties. The influence in expansivity by additions of calcium magnesium carbonate in a composition of wall tile bodies has been investigated. The relative content of mineralogical components was determined by X-ray diffraction and thermal expansion by dilatometric measurements. The results was indicated that with the effect of calcium-magnesium phases and porosity on thermal expansion of wall tile bodies. (author)

  10. Effect of adsorbent addition on floc formation and clarification.

    Younker, Jessica M; Walsh, Margaret E

    2016-07-01

    Adding adsorbent into the coagulation process is an emerging treatment solution for targeting hard-to-remove dissolved organic compounds from both drinking water and industrial wastewater. The impact of adding powdered activated carbon (PAC) or organoclay (OC) adsorbents with ferric chloride (FeCl3) coagulant was investigated in terms of potential changes to the coagulated flocs formed with respect to size, structure, and breakage and regrowth properties. The ability of dissolved air flotation (DAF) and sedimentation (SED) clarification processes to remove hybrid adsorbent-coagulant flocs was also evaluated through clarified water quality analysis of samples collected in bench-scale jar test experiments. The jar tests were conducted using both a synthetic fresh water and oily wastewater test water spiked with dissolved aromatic compounds phenol and naphthalene. Results of the study demonstrated that addition of adsorbent reduced the median coagulated floc size by up to 50% but did not affect floc strength or regrowth potential after application of high shear. Experimental results in fresh water demonstrated that sedimentation was more effective than DAF for clarification of both FeCl3-PAC and FeCl3-OC floc aggregates. However, experimental tests performed on the synthetic oily wastewater showed that coagulant-adsorbent floc aggregates were effectively removed with both DAF and sedimentation treatment, with lower residual turbidity achieved in clarified water samples than with coagulation treatment alone. Addition of OC or PAC into the coagulation process resulted in removals of over half, or nearly all of the dissolved aromatics, respectively. PMID:27064206

  11. Understanding the distribution of fitness effects of mutations by a biophysical-organismal approach

    Bershtein, Shimon

    2011-03-01

    The distribution of fitness effects of mutations is central to many questions in evolutionary biology. However, it remains poorly understood, primarily due to the fact that a fundamental connection that exists between the fitness of organisms and molecular properties of proteins encoded by their genomes is largely overlooked by traditional research approaches. Past efforts to breach this gap followed the ``evolution first'' paradigm, whereby populations were subjected to selection under certain conditions, and mutations which emerged in adapted populations were analyzed using genomic approaches. The results obtained in the framework of this approach, while often useful, are not easily interpretable because mutations get fixed due to a convolution of multiple causes. We have undertaken a conceptually opposite strategy: Mutations with known biophysical and biochemical effects on E. coli's essential proteins (based on computational analysis and in vitro measurements) were introduced into the organism's chromosome and the resulted fitness effects were monitored. Studying the distribution of fitness effects of such fully controlled replacements revealed a very complex fitness landscape, where impact of the microscopic properties of the mutated proteins (folding, stability, and function) is modulated on a macroscopic, whole genome level. Furthermore, the magnitude of the cellular response to the introduced mutations seems to depend on the thermodynamic status of the mutant.

  12. Mutation induction for domestication of Cuphea: Effects of gamma rays

    Full text: Oils of the so called lauric acid group plants are very interesting for industries commercially because of their relatively high content of saturated medium chain triglycerides (MCT), in particular lauric acid (C12:0). Steep melting point curves and low melting points make these oils particularly suitable as fats for synthetic creams, hard butters and similar products; sodium soaps of MCT's are hard, stable to oxidation, and free lathering. Palm kernel oil from Elaeis guineensis Jacq. and coconut oil from Cocos nucifera L. are the two most important commercial source of MCT's for the chemical industry. However, because of large variation in production and price, industries became interested in a continuous supply of MCT's from other species. The genus Cuphea (Lythraceae) contains a large number of herbaceous annuals adapted to temperate climate whose seed oil contains high levels of MCT's. Unfortunately, a common characteristic of the wild species is seed shattering during ripening. Seed shattering could be due to floral zygomorphy which causes the placenta to rupture the ovary wall during development, exposing the seeds; exposed seeds dry and are quickly shed. Seed dormancy is another major deterrent to the agronomic use of Cuphea. It appears to result from hard seed coats as well as from physiological factors and can be effectively broken only by prolonged after-ripening (up to a year). Natural genetic variation in Cuphea does not appear to be suitable for the development of non-shattering types. Therefore, the potential of broadening genetic variation through mutagenesis (using EMS) was investigated, first in the autogamous species C. aperta and in the allogamous species C. lanceolata, and C. procumbens. Mutants having somewhat improved seed retention were selected from all three species, however, expressivity was complete only in C. aperta. According to HIRSINGER and ROEBBELEN, the autogamous species C. tolucana Peyr. (n=12) and C. wrightii A. Gray

  13. Synergistic and compensatory effects of two point mutations conferring target-site resistance to fipronil in the insect GABA receptor RDL.

    Zhang, Yixi; Meng, Xiangkun; Yang, Yuanxue; Li, Hong; Wang, Xin; Yang, Baojun; Zhang, Jianhua; Li, Chunrui; Millar, Neil S; Liu, Zewen

    2016-01-01

    Insecticide resistance can arise from a variety of mechanisms, including changes to the target site, but is often associated with substantial fitness costs to insects. Here we describe two resistance-associated target-site mutations that have synergistic and compensatory effects that combine to produce high and persistent levels of resistance to fipronil, an insecticide targeting on γ-aminobytyric acid (GABA) receptors. In Nilaparvata lugens, a major pest of rice crops in many parts of Asia, we have identified a single point mutation (A302S) in the GABA receptor RDL that has been identified previously in other species and which confers low levels of resistance to fipronil (23-fold) in N. lugans. In addition, we have identified a second resistance-associated RDL mutation (R300Q) that, in combination with A302S, is associated with much higher levels of resistance (237-fold). The R300Q mutation has not been detected in the absence of A302S in either laboratory-selected or field populations, presumably due to the high fitness cost associated with this mutation. Significantly, it appears that the A302S mutation is able to compensate for deleterious effects of R300Q mutation on fitness cost. These findings identify a novel resistance mechanism and may have important implications for the spread of insecticide resistance. PMID:27557781

  14. Mutational Effects on the Folding Dynamics of a Minimized Hairpin‡

    Scian, Michele; Shu, Irene; Olsen, Katherine A.; Hassam, Khalil; Andersen, Niels H.

    2013-01-01

    The fold stabilities and folding dynamics of a series of mutants of a model hairpin, KTW-NPATGK-WTE (HP7), are reported. The parent system and the corresponding DPATGK loop species display sub-μs folding time constants. The mutational studies revealed that ultrafast folding requires both some pre-structuring of the loop and a favorable interaction between the chain termini at the transition state. In the case of YY-DPETGT-WY, another sub-μs folding species [Davis, C. M.; Xiao, S.; Raleigh, D....

  15. Effect of the uvrD mutation on excision repair.

    Kuemmerle, N B; Masker, W E

    1980-01-01

    A pair of related Escherichia coli K-12 strains, one of which contains the uvrD101 mutation, were constructed and compared for ability to perform various steps in the excision repair of deoxyribonucleic acid damage inflicted by ultraviolet radiation. The results of this study indicated: (i) ultraviolet sensitivity in the uvrD101 mutant was greater than that of wild type but less than that measured in an incision-deficient uvrA mutant; (ii) host cell reactivation paralleled the survival data; ...

  16. AML1-ETO expression is directly involved in the development of acute myeloid leukemia in the presence of additional mutations

    Yuan, Youzhong; Zhou, Liming; Miyamoto, Toshihiro; Iwasaki, Hiromi; Harakawa, Nari; Hetherington, Christopher J.; Burel, Sebastien A.; Lagasse, Eric; Weissman, Irving L.; Akashi, Koichi; Zhang, Dong-Er

    2001-01-01

    The t(8;21) is one of the most frequent chromosomal abnormalities associated with acute myeloid leukemia (AML). The translocation, which involves the AML1 gene on chromosome 21 and the ETO gene on chromosome 8, generates an AML1-ETO fusion transcription factor. To examine the effect of the AML1-ETO fusion protein on leukemogenesis, we made transgenic mice in which expression of AML1-ETO is under the control of the human MRP8 promoter (hMRP8-AML1-ETO). AML1-ETO is specifically expressed in mye...

  17. Radical effects on mutation spectra in lambda phage

    Mutations in the lambda repressor gene cI (710 bp) were induced by 60Co-gamma radiation in dissolved lambda phage DNA. After in vitro DNA packaging to lambda phage particles (pack phage) and phenotypic expression of the mutants, DNA was sequenced directly. Two-thirds of mutations were located in the amino terminus region of the gene without any signs of hotspots. Changes consisted of (+1) insertions (25%) and base substitutions (75%). Transitions were exclusively G/C to A/T. Transversions were mostly G/C to C/G and few G/C to T/A. A/T to T/A transversions, A/T to G/C transitions, deletions and gross rearrangements were not found. In most of the base substitutions a pre-existing base pair had been replaced by an A/T pair; this might come from 'non- instructional sites' like abasic sites. Several mechanisms for base substitutions are considered. (author)

  18. Effect of the uvrD mutation on excision repair

    A pair of related Escherichia coli K-12 strains, one of which contains the uvrD101 mutation, were constructed and compared for ability to perform various steps in the excision repair of deoxyribonucleic acid damage inflicted by ultraviolet radiation. The results of this study indicated: (i) ultraviolet sensitivity in the uvrD101 mutant was greater than that of wild type but less than that measured in an incision-deficient uvrA mutant; (ii) host cell reactivation paralleled the survival data; (iii) postirradiation deoxyribonucleic acid degradation was virtually identical in the two strains; (iv) incision, presumably at the sites of pyrimidine dimers, proceeded normally in the uvrD101 strain; (v) excision of pyrimidine dimers was markedly reduced in both rate and extent in the uvrD101 mutant; (vi) the amount of repair resynthesis was the same in both strains, and there was no evidence of abnormally long repair patches in the uvrD mutant; and (vii) rejoining of incision breaks was slow and incomplete in the uvrD strain. These data suggest that the ultraviolet sensitivity conferred by the uvrD mutation arises from inefficient removal of pyrimidine dimers or from failure to close incision breaks. The data are compatible with the notion that the uvrD+ gene product affects the conformation of incised deoxyribonucleic acid molecules

  19. Effect of the uvrD mutation on excision repair

    Kuemmerle, N.B.; Masker, W.E.

    1980-05-01

    A pair of related Escherichia coli K-12 strains, one of which contains the uvrD101 mutation, were constructed and compared for ability to perform various steps in the excision repair of deoxyribonucleic acid damage inflicted by ultraviolet radiation. The results of this study indicated: (i) ultraviolet sensitivity in the uvrD101 mutant was greater than that of wild type but less than that measured in an incision-deficient uvrA mutant; (ii) host cell reactivation paralleled the survival data; (iii) postirradiation deoxyribonucleic acid degradation was virtually identical in the two strains; (iv) incision, presumably at the sites of pyrimidine dimers, proceeded normally in the uvrD101 strain; (v) excision of pyrimidine dimers was markedly reduced in both rate and extent in the uvrD101 mutant; (vi) the amount of repair resynthesis was the same in both strains, and there was no evidence of abnormally long repair patches in the uvrD mutant; and (vii) rejoining of incision breaks was slow and incomplete in the uvrD strain. These data suggest that the ultraviolet sensitivity conferred by the uvrD mutation arises from inefficient removal of pyrimidine dimers or from failure to close incision breaks. The data are compatible with the notion that the uvrD+ gene product affects the conformation of incised deoxyribonucleic acid molecules.

  20. Age and sex effects on human mutation rates. An old problem with new complexities

    Base substitution mutations are far more common in human males than in females, and the frequency increases with paternal age. Both can be accounted for by the greater number of pre-meiotic cell divisions in males, especially old ones. In contrast, small deletions do not show any important age effect and occur with approximately equal frequency in the two sexes. Mutations in most genes include both types, and the sex and paternal age effect depends on the proportion of the two types. A few traits, of which Apert Syndrome is best understood, are mutation hot spots with all the mutations occurring in one or two codons, usually at one nucleotide. They occur with very high frequency almost exclusively in males and the frequency increases rapidly with paternal age. It has been suggested that the mutant cells have a selective advantage in the male germ-line prior to meiosis. Evidence for this surprising, but important, hypothesis is discussed. A possible mechanism is the conversion of asymmetrical stem-cell divisions into symmetric ones. Some traits with complex etiology show a slight paternal age effect. There is also a short discussion of the high deleterious mutation rate and the role of sexual reproduction in reducing the consequent mutation load. (author)

  1. Differential effects of human L1CAM mutations on complementing guidance and synaptic defects in Drosophila melanogaster.

    Sirisha Kudumala

    Full Text Available A large number of different pathological L1CAM mutations have been identified that result in a broad spectrum of neurological and non-neurological phenotypes. While many of these mutations have been characterized for their effects on homophilic and heterophilic interactions, as well as expression levels in vitro, there are only few studies on their biological consequences in vivo. The single L1-type CAM gene in Drosophila, neuroglian (nrg, has distinct functions during axon guidance and synapse formation and the phenotypes of nrg mutants can be rescued by the expression of human L1CAM. We previously showed that the highly conserved intracellular FIGQY Ankyrin-binding motif is required for L1CAM-mediated synapse formation, but not for neurite outgrowth or axon guidance of the Drosophila giant fiber (GF neuron. Here, we use the GF as a model neuron to characterize the pathogenic L120V, Y1070C, C264Y, H210Q, E309K and R184Q extracellular L1CAM missense mutations and a L1CAM protein with a disrupted ezrin-moesin-radixin (ERM binding site to investigate the signaling requirements for neuronal development. We report that different L1CAM mutations have distinct effects on axon guidance and synapse formation. Furthermore, L1CAM homophilic binding and signaling via the ERM motif is essential for axon guidance in Drosophila. In addition, the human pathological H210Q, R184Q and Y1070C, but not the E309K and L120V L1CAM mutations affect outside-in signaling via the FIGQY Ankyrin binding domain which is required for synapse formation. Thus, the pathological phenotypes observed in humans are likely to be caused by the disruption of signaling required for both, guidance and synaptogenesis.

  2. ISOLATION OF ENDOPHYTIC ACTINOMYCETES FROM MEDICINAL PLANTS AND ITS MUTATIONAL EFFECT IN BIOCONTROL ACTIVITY

    Hema Shenpagam N.*, D. Kanchana Devi ** and Sinduja G.

    2012-11-01

    Full Text Available In the present study, the endophytic actinomycetes were collected from three medicinal plants Azadiracta indica, Ocimum sanctum and Phyllanthus amarus. Endophytic actinomycetes were isolated using different media like Starch casein agar, Starch casein nitrate agar, Actinomycetes isolation agar and Soyabean agar, while it showed more colonies in Starch casein agar. The endophytic actinomycetes were stained and biochemical tests were performed. Antimicrobial compound was purified from the filtrate by ethanol extraction method. Antagonistic activities of endophytic actinomycetes isolates were tested against bacterial pathogens (Staphylococcus aureus, Streptococcus pyogenes, Klebsiella pneumoniae and Pseudomonas aeruginosa and the fungi Rhizopus. For the selected isolates antibiotic resistance was checked using various antibiotic discs like Amoxycillin, Penicillin, Rifampicin and Ampicillin. The strains which showed efficient antibacterial activity were selected to study the effect of mutation by physical and chemical method. In this study, UV mutated endophytic actinomycetes increase antibiotic production than non-mutated endophytic Actinomycetes, whereas in chemical mutation it does not increase the antibiotic production.

  3. Human immunodeficiency virus type 1 integrase: effect on viral replication of mutations at highly conserved residues.

    Cannon, P M; Wilson, W; Byles, E; Kingsman, S M; Kingsman, A J

    1994-08-01

    Sequence comparisons of the integrase (IN) proteins from different retroviruses have identified several highly conserved residues. We have introduced mutations at 16 of these sites into the integrase gene of human immunodeficiency virus type 1 and analyzed the phenotypes of the resulting viruses. The viruses were all normal for p24 content and reverse transcriptase activity. In addition, all of the mutants could infect T-cell lines and undergo reverse transcription, as assessed by PCR analysis. Most of the mutant viruses also had normal Western blot (immunoblot) profiles, although three of the mutations resulted in reduced signals for IN relative to the wild type on the immunoblots and mutation of residue W235 completely abolished recognition of the protein by pooled sera from human immunodeficiency virus type 1-positive patients. Mutations that have previously been shown to abolish activity in in vitro studies produced noninfectious viruses. The substitution of W235 was notable in producing a noninfectious virus, despite previous reports of this residue being nonessential for IN activity in vitro (A.D. Leavitt, L. Shiue, and H.E. Varmus, J. Biol. Chem. 268:2113-2119, 1993). In addition, we have identified four highly conserved residues that can be mutated without any affect on viral replication in T-cell lines. PMID:8035478

  4. Effect of solid additives on pyrolysis behaviour of Makerwal coal

    Ahmad, T.; Nisar, J.; Awan, I.A.; Ahmad, I. [University of Peshawar, Peshawar (Pakistan)

    2009-02-15

    The method used in this study provides a quantitative description of the relationship between the chemical structure of coal and the physical and chemical properties of the resultant pyrolysis products (gas, tar, liquid, and char). The purpose of this study is to investigate the effect of inorganic solid additives (Na{sub 2}CO{sub 3}, K{sub 2}CO{sub 3}, CaCO{sub 3}, MgCO{sub 3}, Fe{sub 2}O{sub 3} and CaSO{sub 4},), on flash pyrolysis of high volatile bituminous coal samples from Makerwal coalfields by using open tubular type pyrolyzer coupled with gas chromatography. Two different coal samples were selected for this purpose. The sampling apparatus consisted of two traps in order to separate the products into fractions on the basis of their volatility such as tar, liquid, and gaseous fractions. The product yields released from each sample in their raw, de-mineralized and salt treated form were monitored. The gaseous fractions were directly introduced to GC for identification. The gases were C{sub 1}-C{sub 5}, hydrocarbons. The pyrolysis was carried out at 690{sup o}C. Some evaluations and comparisons, from the results obtained, are presented.

  5. I-129 Moessbauer effect of polyacetylene with iodine addition

    The I-129 Moessbauer effect of polyacetylene with iodine addition was measured. The gamma-ray used was emitted from the first excited state of I-129, which is a decay product of Te-129. The Te-129 was produced by neutron irradiation of ZnTe128. The state of iodine in the #betta#-carotene-iodine complex was studied by the Moessbauer method. An obtained Moessbauer spectrum showed the presence of two kinds of iodine. As a result, it can be said that the #betta#-carrotene iodine complex is present in an ionic state of (C40H56)+ I3-. The states of iodine doped into cis- and trans-polyacetylene were also measured by the Moessbauer method. The test samples were made by dipping the polyacetylene into carbon tetrachloride solution of iodine. The obtained Moessbauer spectra were more complex than that of the #betta#-carotene iodine complex. Eight components of iodine were assumed for the analysis of spectra. It is suggested that the iodine states in polyacetylene are I3- and I5-. The I5- ions are linear. The number of I5- increases with increase of the iodine concentration in cis and trans polyacetylene. (Kato, T.)

  6. Effects of Several Purple Potato Additions on Bread Quality

    Bădărău Carmen Liliana

    2016-04-01

    Full Text Available Potato cultivars with purple flesh represent an efficient and natural source of antioxidants, this vegetable having high content in polyphenols (especially anthocyanin pigments. The research goal of this work was to evaluate the anthocyanin and polyphenols content of several Romanian potato varieties (Albastru-Violet de Gălănești and Christian and the effects of these potatoes (add to dough in different proportions on several bread quality indicators. The bread quality depends on physical and chemical properties and on several signs like: flavor and taste, external appearance, crumb porosity and texture, bread’s volume. In this research experiment, beside the total polyphenols and anthocyanin content, the analysis performed on bread (prepared using different potatoes addition 5%, 15% and 30% were sensorial and physic chemical analysis (product volume, crumb porosity, height/diameter ratio, moist and acidity. Experimental results indicated that 15% purple potato cultivar added on the dough was the most indicate proportion to be used in bread processing.

  7. Mutation accumulation and fitness effects in hybridogenetic populations: a comparison to sexual and asexual systems

    Bagheri Homayoun C

    2007-05-01

    Full Text Available Abstract Background Female only unisexual vertebrates that reproduce by hybridogenesis show an unusual genetic composition. They are of hybrid origin but show no recombination between the genomes of their parental species. Instead, the paternal genome is discarded from the germline prior to meiosis, and gametes (eggs only contain solely unrecombined maternal genomes. Hence hybridogens only transmit maternally inherited mutations. Hybridity is restored each generation by backcrossing with males of the sexual parental species whose genome was eliminated. In contrast, recombining sexual species propagate an intermixed pool of mutations derived from the maternal and paternal parts of the genome. If mutation rates are lower in female gametes than males, it raises the possibility for lower mutation accumulation in a hybridogenetic population, and consequently, higher population fitness than its sexual counterpart. Results We show through Monte-Carlo simulations that at higher male to female mutation ratios, and sufficiently large population sizes, hybridogenetic populations can carry a lower mutation load than sexual species. This effect is more pronounced with synergistic forms of epistasis. Mutations accumulate faster on the sexual part of the genome, and with the purifying effects of epistasis, it makes it more difficult for mutations to be transmitted on the clonal part of the genome. In smaller populations, the same mechanism reduces the speed of Muller's Ratchet and the number of fixed mutations compared to similar asexual species. Conclusion Since mutation accumulation can be less pronounced in hybridogenetic populations, the question arises why hybridogenetic organisms are so scarce compared to sexual species. In considering this, it is likely that comparison of population fitnesses is not sufficient. Despite competition with the sexual parental species, hybrid populations are dependent on the maintenance of – and contact with – their

  8. Electrodeposition of Asphaltenes. 2. Effect of Resins and Additives

    Khvostichenko, Daria S; Andersen, Simon Ivar

    2010-01-01

    Electrodeposition of asphaltenes from oil/heptane, asphaltene/heptane, and asphaltene/heptane/additive mixtures has been investigated. Toluene, native petroleum resins, and a synthetic asphaltene dispersant, p-nonylphenol, were used as additives. The addition of these components led to partial...... preparation of the mixture and the toluene content. Introduction of petroleum resins into asphaltene/heptane mixtures resulted in neutralization of the asphaltene particle charge. The addition of p-nonylphenol to asphaltene suspensions in heptane did not alter the charge of asphaltene particles. Current...

  9. Effect of Additional Structure on Effective Stack Height of Gas Dispersion in Atmosphere

    Takenobu Michioka

    2016-03-01

    Full Text Available Wind-tunnel experiments were conducted to evaluate the effect of additional structure (building, sea wall and banking on the effective stack height, which is usually used in safety analyses of nuclear power facilities in Japan. The effective stack heights were estimated with and without the additional structure in addition to the reactor building while varying several conditions such as the source height, the height of additional structure and the distance between the source position and the additional structure. When the source height is equivalent to the reactor building height, the additional structure enhances both the vertical and horizontal gas dispersion widths and decreases the ground gas concentration, and it means that the additional structure does not decrease the effective stack height. When the source height is larger than the reactor height, the additional structures might affect the effective stack height. As the distance between the source and the additional structure decreases, or as the height of the additional structure increases, the structure has a larger effect on the effective stack height.

  10. Ecotoxicological effects of activated carbon addition to sediments.

    Jonker, M.T.O.; Suijkerbuijk, M.P.; Schmitt, H.; Sinnige, T.L.

    2009-01-01

    Activated carbon (AC) addition is a recently developed technique for the remediation of sediments and soils contaminated with hydrophobic organic chemicals. Laboratory and field experiments have demonstrated that the addition of 3-4% of AC can reduce aqueous concentrations and the bioaccumulation po

  11. Chemistry of Food Additives: Direct and Indirect Effects.

    Pauli, George H.

    1984-01-01

    The primary component(s), impurities, and degradation products of polysorbate 80, nitrate and nitrite salts, and diethylpyrocarbonate (DEPC) are discussed. Safety considerations related to these food additives are also noted. The chick-edema factor which results from an additive in poultry feed is also discussed. (JN)

  12. Two heterozygous Cav3.2 channel mutations in a pediatric chronic pain patient: recording condition-dependent biophysical effects.

    Souza, Ivana A; Gandini, Maria A; Wan, Miranda M; Zamponi, Gerald W

    2016-04-01

    We report expression system-dependent effects of heterozygous mutations (P769L and A1059S) in the Cav3.2 CACNA1H gene identified in a pediatric patient with chronic pain and absence seizures. The mutations were introduced individually into recombinant channels and then analyzed by means of electrophysiology. When both mutants were co-expressed in tsA-201 cells, we observed a loss of channel function, with significantly smaller current densities across a wide range of voltages (-40 to +20 mV). In addition, when both mutant channels were co-expressed, the channels opened at a more depolarizing potential with a ~5-mV right shift in the half-activation potential, with no changes in half-inactivation potential and the rate of recovery from inactivation. Interestingly, when both mutants were co-expressed in the neuronal-derived CAD cells in a different extracellular milieu, the effect was remarkably different. Although not statistically significant (p replacement of extracellular sodium and potassium with tetraethylammonium chloride. Our results show that experimental conditions can be a confounding factor in the biophysical effects of T-type calcium channel mutations found in certain neurological disorders. PMID:26706850

  13. The effects of in utero irradiation on mutation induction and transgenerational instability in mice

    Barber, Ruth C.; Hardwick, Robert J.; Shanks, Morag E.; Glen, Colin D.; Mughal, Safeer K.; Voutounou, Mariel [Department of Genetics, University of Leicester, University Road, Leicester, LE1 7RH (United Kingdom); Dubrova, Yuri E., E-mail: yed2@le.ac.uk [Department of Genetics, University of Leicester, University Road, Leicester, LE1 7RH (United Kingdom)

    2009-05-12

    Epidemiological evidence suggests that the deleterious effects of prenatal irradiation can manifest during childhood, resulting in an increased risk of leukaemia and solid cancers after birth. However, the mechanisms underlying the long-term effects of foetal irradiation remain poorly understood. This study was designed to analyse the impact of in utero irradiation on mutation rates at expanded simple tandem repeat (ESTR) DNA loci in directly exposed mice and their first-generation (F{sub 1}) offspring. ESTR mutation frequencies in the germline and somatic tissues of male and female mice irradiated at 12 days of gestation remained highly elevated during adulthood, which was mainly attributed to a significant increase in the frequency of singleton mutations. The prevalence of singleton mutations in directly exposed mice suggests that foetal irradiation results in genomic instability manifested both in utero and during adulthood. The frequency of ESTR mutation in the F{sub 1} offspring of prenatally irradiated male mice was equally elevated across all tissues, which suggests that foetal exposure results in transgenerational genomic instability. In contrast, maternal in utero exposure did not affect the F{sub 1} stability. Our data imply that the passive erasure of epigenetic marks in the maternal genome can diminish the transgenerational effects of foetal irradiation and therefore provide important clues to the still unknown mechanisms of radiation-induced genomic instability. The results of this study offer a plausible explanation for the effects of in utero irradiation on the risk of leukaemia and solid cancers after birth.

  14. In silico investigation of molecular effects caused by missense mutations in creatine transporter protein

    Zhang, Zhe; Schwatz, Charles; Alexov, Emil

    2011-03-01

    Creatine transporter (CT) protein, which is encoded by SLC6A8 gene, is essential for taking up the creatine in the cell, which in turn plays a key role in the spatial and temporal maintenance of energy in skeletal and cardiac muscle cells. It was shown that some missense mutations in CT cause mental retardation, while others are harmless non-synonymous single nucleoside polymorphism (nsSNP). Currently fifteen missense mutations in CT are known, among which twelve are disease-causing. Sequence analysis reveals that there is no clear trend distinguishing disease-causing from harmless missense mutations. Because of that, we built 3D model of the CT using highly homologous template and use the model to investigate the effects of mutations of CT stability and hydrogen bond network. It is demonstrated that disease-causing mutations affect the folding free energy and ionization states of titratable group in much greater extend as compared with harmless mutations. Supported by grants from NLM, NIH, grant numbers 1R03LM009748 and 1R03LM009748-S1.

  15. Concentration addition, independent action and generalized concentration addition models for mixture effect prediction of sex hormone synthesis in vitro

    Hadrup, Niels; Taxvig, Camilla; Pedersen, Mikael;

    2013-01-01

    of the concentration addition (CA), independent action (IA) and generalized concentration addition (GCA) models. First we measured effects of single chemicals and mixtures thereof on steroid synthesis in H295R cells. Then single chemical data were applied to the models; predictions of mixture effects were calculated...... and compared to the experimental mixture data. Mixture 1 contained environmental chemicals adjusted in ratio according to human exposure levels. Mixture 2 was a potency adjusted mixture containing five pesticides. Prediction of testosterone effects coincided with the experimental Mixture 1 data. In contrast...

  16. Correlated mutations in protein sequences: Phylogenetic and structural effects

    Lapedes, A.S. [Los Alamos National Lab., NM (United States). Theoretical Div.]|[Santa Fe Inst., NM (United States); Giraud, B.G. [C.E.N. Saclay, Gif/Yvette (France). Service Physique Theorique; Liu, L.C. [Los Alamos National Lab., NM (United States). Theoretical Div.; Stormo, G.D. [Univ. of Colorado, Boulder, CO (United States). Dept. of Molecular, Cellular and Developmental Biology

    1998-12-01

    Covariation analysis of sets of aligned sequences for RNA molecules is relatively successful in elucidating RNA secondary structure, as well as some aspects of tertiary structure. Covariation analysis of sets of aligned sequences for protein molecules is successful in certain instances in elucidating certain structural and functional links, but in general, pairs of sites displaying highly covarying mutations in protein sequences do not necessarily correspond to sites that are spatially close in the protein structure. In this paper the authors identify two reasons why naive use of covariation analysis for protein sequences fails to reliably indicate sequence positions that are spatially proximate. The first reason involves the bias introduced in calculation of covariation measures due to the fact that biological sequences are generally related by a non-trivial phylogenetic tree. The authors present a null-model approach to solve this problem. The second reason involves linked chains of covariation which can result in pairs of sites displaying significant covariation even though they are not spatially proximate. They present a maximum entropy solution to this classic problem of causation versus correlation. The methodologies are validated in simulation.

  17. Effect of cationic polyelectrolytes addition in cement cohesion

    Edison Albert Zuluaga-Hernández; Bibian A Hoyos

    2014-01-01

    Here is studied the variation in cohesion of cement main phase (C-S-H) as a result of cationic polyelectrolytes addition (quaternary amines spermine and norspermidine). Cohesion study was carried out by molecular simulation techniques (Monte Carlo) using a primitive model in a canonical ensemble (NVT). The proposed model takes into account the influence of ionic size of each particle and the addition of polyelectrolytes with different charge number and separation. The results obtained show th...

  18. On the effect of thallium additions on cadmium amalgam potentials

    A study has been made of the influence of additives of thallium on potentials of cadmium amalgams with thallium contents of 10, 20, 30, and 40 at.% at 20, 40, 60, and 80 deg C. Additives of thallium have been found to shift the potential of cadmium amalgams towards the range of negative values which indicates an increase in the activity of cadmium. A possibility of calculation of the potential shift for heterogeneous cadmium amalgams on introducing thallium has been shown

  19. The effect of point mutations on structure and mechanical properties of collagen-like fibril: A molecular dynamics study

    Marlowe, Ashley E.; Singh, Abhishek; Yingling, Yaroslava G., E-mail: yara_yingling@ncsu.edu

    2012-12-01

    Understanding sequence dependent mechanical and structural properties of collagen fibrils is important for the development of artificial biomaterials for medical and nanotechnological applications. Moreover, point mutations are behind many collagen associated diseases, including Osteogenesis Imperfecta (OI). We conducted a combination of classical and steered atomistic molecular dynamics simulations to examine the effect of point mutations on structure and mechanical properties of short collagen fibrils which include mutations of glycine to alanine, aspartic acid, cysteine, and serine or mutations of hydroxyproline to arginine, asparagine, glutamine, and lysine. We found that all mutations disrupt structure and reduce strength of the collagen fibrils, which may affect the hierarchical packing of the fibrils. The glycine mutations were more detrimental to mechanical strength of the fibrils (WT > Ala > Ser > Cys > Asp) than that of hydroxyproline (WT > Arg > Gln > Asn > Lys). The clinical outcome for glycine mutations agrees well with the trend in reduction of fibril's tensile strength predicted by our simulations. Overall, our results suggest that the reduction in mechanical properties of collagen fibrils may be used to predict the clinical outcome of mutations. Highlights: Black-Right-Pointing-Pointer All mutations disrupt structure and bonding pattern and reduce strength of the collagen fibrils. Black-Right-Pointing-Pointer Gly based mutations are worst to mechanical integrity of fibrils than that of Hyp. Black-Right-Pointing-Pointer Lys and Arg mutations most dramatically destabilize collagen fibril properties. Black-Right-Pointing-Pointer Clinical outcome of mutations may be related to the reduced mechanical properties of fibrils.

  20. Effect of mutated IκBα transfection on multidrug resistance in hilar cholangiocarcinoma cell lines

    Ru-Fu Chen; Zhi-Hua Li; Xian-He Kong; Ji-Sheng Chen

    2005-01-01

    AIM: To explore the expression effect of mutated IκBαtransfection on multidrug resistance gene (MDR-1) in hilar cholangiocarcinoma cells by inhibiting the activity of nuclear transcription factor-κB (NF-κB).METHODS: We used the mutated IκBα plasmid to transfect QBC939HCVC+ cells and QBC939 cells, and electrophoretic gel mobility shift assay (EMSA) to detect the binding activity of NF-κB DNA and the effect of the transfrecting mutated IκBα plasmid on multidrug resistance gene (MDR-1) in hilar cholangiocarcinoma cells and its expression protein (P-GP).RFSULTS: Plasmid DNA was digested by restriction enzymes Xbal and Hand Ⅲ, and its product after electrophoresis showed two bands with a big difference in molecular weight,with a size of 4.9 kb and 1.55 kb respectively, which indicated that the carrier was successfully constructed and digested with enzymes. The radioactivity accumulation of QBC939HCVC+and QBC939 cells transfected with mutated IκBα plasmid was significantly lower than that of the control group not transfected with mutated IκBα plasmid. Double densimeter scanning showed that the relative signal density between the tansfection group and non-transfection group was significantly different, which proved that the mutated IκBα plasmid could inhibit the binding activity of NF-κB DNA in hilar cholangiocarcinoma cells. Compared to control group not transfected with m IκBα plasmid, the expression level of MDR-1mRNA in the QBC939 and QBC939HCVC+ cells transfected with mutated IκBα plasmid was lower. The expression intensity of P-GP protein in QBC939 and QBC939HCVC+ cells transfected with mutated IκBα was significantly lower than that of the control group not transfected with mutated IκBα plasmid.CONCLUSION: The mutated IκBα plasmid transfection can markedly reverse the multidrug resistance of hilar cholangiocarcinoma cells. Interruption of NF-κB activity may become a new target in gene therapy for hilar cholangiocarcinogenesic carcinoma.

  1. The effect of β2-α2 loop mutation on amyloidogenic properties of the prion protein

    Dutta, Arpana; Chen, Shugui; Surewicz, Witold K.

    2013-01-01

    Recent studies revealed that elk-like S170N/N174T mutation in mouse prion protein (moPrP), which results in an increased rigidity of β2-α2 loop, leads to a prion disease in transgenic mice. Here we characterized the effect of this mutation on biophysical properties of moPrP. Despite similar thermodynamic stabilities of wild type and mutant proteins, the latter was found to have markedly higher propensity to form amyloid fibrils. Importantly, this effect was observed even under fully denaturin...

  2. The Effect Acid Addition on Characteristic Effervescent Tablet of Tamarillo

    Fidela Violalita

    2015-01-01

    Full Text Available The aim of study was to determine the percentage of acid and its influence on characteristic effervescent tablet of tamarillo. The percentages of  acid addition that consist with citric acid and tartaric acid (1:1 were 15%, 20%, 25%, 30% and 35%. Water content, pH solution, vitamin C content, soluble duration, friability of tablet and organoleptic test on colour, aroma and flavour of tamarillo effervescent tablet were determined after addition of acid. The results showed that the difference in percentage of acid addition significantly affected to the water content, pH solution, soluble duration and friability of tablets. Based on organoleptic test, the tablet consist of 25% addition of acid was the best percentage of acid addition. The quality parameters in this percentage were the water content 6.09%, pH solution 4.80,  vitamin C 498.0800 mg/tablet, soluble duration 3.96 minute, friability of tablet 0.11%, while the averages of organoleptic test for colour were 3.40 (ordinary, aroma 3.36 (ordinary, and flavour 3.76 (like.

  3. The cosmological constant. A small addition with a great effect

    The consequences of a cosmological constant Λ to cosmological models on the one hand and to Newton's gravitational law in the weak field expansion on the other hand are discussed. In case of a negative Λ with Λ∼10-56 cm-2 the universe is open but does not expand forever. Furthermore, its age is compatible with the age of the oldest globular clusters. On the other hand, Newton's gravitational law is modified by an additional attractive force term linearly increasing woth the distance. This term acts only over very large distances. If one assumes a value Λ∼=-10-56 cm-2 the additional term acts for stars over a characteristic scale of about 120 pc and for galaxies over a characteristic scale of about 0.8 Mpc. A positive cosmological constant Λ∼=-10-56 cm-2 leads to an additional repulsive force which would have prevented the existence of galaxy clusters

  4. Effect of space flight mutation on eggplant and analysis of genetic diversity by ssr molecular marker

    Seeds of three eggplant varieties (05 - 7, 05 - 9 and 05 - 18) were carried byShijian 8satellite for space flight treatment. The space flight mutation effects on eggplant were studied and the genetic diversity of mutant lines was analyzed using SSR markers. The results showed that space flight had obvious effects on the seed germination in eggplant SP1 generation and other characters such as plant height, plant type, leaf shape, fruit shape in the second generation. Most of the mutated characters could stably inherit in the third generation. The results also indicated that different eggplant genotypes resporded different to the space flight mutation; the long eggplant 05 - 18 was much more sensitive than other two varieties. Great variation between variant lines and their original varieties were detected by SSR markers, suggesting that space flight could induce molecular variation in eggplant. (authors)

  5. Effect of shaddock albedo addition on the properties of frankfurters

    Shan, Bing; Li, Xingmin; Pan, Teng; Zheng, Limin; Zhang, Hao; Guo, Huiyuan; JIANG, LU; Zhen, Shaobo; Ren, Fazheng

    2014-01-01

    To explore the potential as a natural auxiliary emulsifier, shaddock albedo was added into frankfurters at six different levels: 0.0, 2.5, 5.0, 7.5, 10 and 12.5 %. The emulsion capacity (EC) of meat batters and cooking properties of frankfurters were evaluated. EC of meat batters was improved with the addition of shaddock albedo and the maximum value was reached at the 5 % albedo concentration. The addition of shaddock albedo resulted in lower cooking losses of frankfurters, with the lowest v...

  6. EFFECTS OF PROPERTIES POLYMERIC ADDITIVES IN RHEOLOGIC AND DRILLING FLUIDS

    Danielly Vieira de Lucena

    2014-03-01

    Full Text Available The influence of carboxymethylcellulose, CMC (filtrate reducer and xanthan gum (viscosifier in plastic and apparent viscosity at yield strength and the volume of filtrate in the composition of drilling fluids based on water was investigated based on statistical design. Five formulations consist of a range of concentrations used commercially were utilized in the design of the experiment. The formulations were prepared in accordance with company standards Petrobras. Regression models were calculated and correlated with the properties of the compositions. The relevance and validation of the models were confirmed by statistical analysis. The design can be applied to statistically optimize the mud properties considering the addition of CMC and xanthan gum, and to provide a better understanding of the influence of additives on the properties of polymer-based fluid system water. From the study it was observed that the values of the rheological properties vary with the concentration of additives, increasing with increasing concentration of the same, and that the concentration of the additives caused a decline of parameter values filtration.

  7. Effects of Video Games as Reinforcers for Computerized Addition Performance.

    Axelrod, Saul; And Others

    1987-01-01

    Four 2nd-grade students completed addition problems on a computer, using video games as reinforcers. Two variable ratio schedules of reinforcement failed to increase student accuracy or the rate of correct responses. In a no-games reinforcement condition, students had more opportunities to respond and had a greater number of correct answers.…

  8. Effect of Calcium Additive on the Crystallization of Struvite

    Perwitasari Dyah Suci

    2016-01-01

    Full Text Available Crystallization of struvite [MgNH4PO4.6H2O] may lead to the deposition of scale which may create significant problems in the process pipes, pumps and other industrial equipment. However, struvite precipitation can be benefited for phosphate recovery for use of fertilizer. The aim at the present work was to investigate calcium additive on struvite precipitation. The experiment was carried out in a batch mode using a 1-liter Pyrex glass vessel mechanically agitated for 200 rpm. The scale-forming solution was prepared for mixing solutions to MgCl2 and NH4H2PO4 with Mg+2 , NH4+ and PO4-3 in a molar ratio of 1: 1:1. The crystallization temperature of 30 and 40 °C was selected. Ca was added into the crystallizing solution to chloride dihydrate 0.4M (CaCl2•2H2O. Then each solution was pH adjusted to 9 by addition of KOH. The crystals obtained were characterized using SEM for morphology, EDS for elemental analysis as well as XRPD Rietveld analysis for crystaline phases. The induction periods varied from 10 to 90 min, which means that the struvite crystals began forming 10 to 90 min after mixing of the solution. It was observed that the Ca additive may inhibit the struvite crystallization. SEM analysis revealed that the struvite crystals obtained were predominantly of irregular prismatic morphology. Furthermore, the EDS pattern revealed that the elemental composition of the crystals consisted of Ca, Cl, S Mg, N, and P, providing that many crystalline phase found in the crystals such as Gypsum, CaCl2, struvite, struvite-(K and sylvite. It was observed that the Ca additive appeared to inhibit the struvite crystallization.

  9. Effects of additives on thermal stability of Li ion cells

    Doughty, Daniel H.; Roth, E. Peter; Crafts, Chris C.; Nagasubramanian, G.; Henriksen, Gary; Amine, Khalil

    Li ion cells are being developed for high-power applications in hybrid electric vehicles, because these cells offer superior combination of power and energy density over current cell chemistries. Cells using this chemistry are proposed for battery systems in both internal combustion engine and fuel cell-powered hybrid electric vehicles. However, the safety of these cells needs to be understood and improved for eventual widespread commercial applications. The thermal-abuse response of Li ion cells has been improved by the incorporation of more stable anode carbons and electrolyte additives. Electrolyte solutions containing vinyl ethylene carbonate (VEC), triphenyl phosphate (TPP), tris(trifluoroethyl)phosphate (TFP) as well as some proprietary flame-retardant additives were evaluated. Test cells in the 18,650 configuration were built at Sandia National Laboratories using new stable electrode materials and electrolyte additives. A special test fixture was designed to allow determination of self-generated cell heating during a thermal ramp profile. The flammability of vented gas and expelled electrolyte was studied using a novel arrangement of a spark generator placed near the cell to ignite vent gas if a flammable gas mixture was present. Flammability of vent gas was somewhat reduced by the presence of certain additives. Accelerating rate calorimetry (ARC) was also used to characterize 18,650-size test cell heat and gas generation. Gas composition was analyzed by gas chromatography (GC) and was found to consist of CO 2, H 2, CO, methane, ethane, ethylene and small amounts of C1-C4 organic molecules.

  10. The effect of chemical additives on the synthesis of ethanol

    Chuang, S.S.C.

    1992-03-06

    The objective of this research was to investigate the reaction mechanism of higher alcohol and aldehyde synthesis from syngas and the role of additives in the synthesis. An in situ IR reaction system and probe molecule technique were developed to study adsorbed species, active sites, and reaction pathway during reaction. The catalysts used for this study included silica-supported Rh, Ru, and Ni. (VC)

  11. Effect of shaddock albedo addition on the properties of frankfurters.

    Shan, Bing; Li, Xingmin; Pan, Teng; Zheng, Limin; Zhang, Hao; Guo, Huiyuan; Jiang, Lu; Zhen, Shaobo; Ren, Fazheng

    2015-07-01

    To explore the potential as a natural auxiliary emulsifier, shaddock albedo was added into frankfurters at six different levels: 0.0, 2.5, 5.0, 7.5, 10 and 12.5 %. The emulsion capacity (EC) of meat batters and cooking properties of frankfurters were evaluated. EC of meat batters was improved with the addition of shaddock albedo and the maximum value was reached at the 5 % albedo concentration. The addition of shaddock albedo resulted in lower cooking losses of frankfurters, with the lowest value obtained at the 7.5 % level. The presence of shaddock albedo decreased the total expressible fluid (TEF) and the proportion of fat in total expressible fluid (PF) which indicated the emulsion stability of frankfurters and the lowest values both occurred at the concentration of 7.5 %. Shaddock albedo inclusion increased the lightness and yellowness of frankfurters and decreased redness. Texture profile analysis showed increased hardness and decreased chewiness of frankfurters with the addition of shaddock albedo. Consequently, shaddock albedo could be a potential source of auxiliary emulsifier filler for emulsion-type meat products. PMID:26139927

  12. Cognitive Effects of Greek Affiliation in College: Additional Evidence

    Pascarella, Ernest T.; Flowers, Lamont; Whitt, Elizabeth J.

    2009-01-01

    Previous research published in this journal found broad-based negative effects of Greek affiliation on standardized measures of cognitive development after 1 year of college. Following the same sample, and employing essentially the same research design and analytic model, the present study found that the negative effects of Greek affiliation were…

  13. Novel C16orf57 mutations in patients with Poikiloderma with Neutropenia: bioinformatic analysis of the protein and predicted effects of all reported mutations

    Colombo Elisa A

    2012-01-01

    Full Text Available Abstract Background Poikiloderma with Neutropenia (PN is a rare autosomal recessive genodermatosis caused by C16orf57 mutations. To date 17 mutations have been identified in 31 PN patients. Results We characterize six PN patients expanding the clinical phenotype of the syndrome and the mutational repertoire of the gene. We detect the two novel C16orf57 mutations, c.232C>T and c.265+2T>G, as well as the already reported c.179delC, c.531delA and c.693+1G>T mutations. cDNA analysis evidences the presence of aberrant transcripts, and bioinformatic prediction of C16orf57 protein structure gauges the mutations effects on the folded protein chain. Computational analysis of the C16orf57 protein shows two conserved H-X-S/T-X tetrapeptide motifs marking the active site of a two-fold pseudosymmetric structure recalling the 2H phosphoesterase superfamily. Based on this model C16orf57 is likely a 2H-active site enzyme functioning in RNA processing, as a presumptive RNA ligase. According to bioinformatic prediction, all known C16orf57 mutations, including the novel mutations herein described, impair the protein structure by either removing one or both tetrapeptide motifs or by destroying the symmetry of the native folding. Finally, we analyse the geographical distribution of the recurrent mutations that depicts clusters featuring a founder effect. Conclusions In cohorts of patients clinically affected by genodermatoses with overlapping symptoms, the molecular screening of C16orf57 gene seems the proper way to address the correct diagnosis of PN, enabling the syndrome-specific oncosurveillance. The bioinformatic prediction of the C16orf57 protein structure denotes a very basic enzymatic function consistent with a housekeeping function. Detection of aberrant transcripts, also in cells from PN patients carrying early truncated mutations, suggests they might be translatable. Tissue-specific sensitivity to the lack of functionally correct protein accounts for the

  14. Founder effect of a prevalent phenylketonuria mutation in the Oriental population

    A missense mutation has been identified in the human phenylalanine hydroxylase Chinese patient with classic phenylketonuria (PKU). A G-to-C transition at the second base of codon 413 in exon 12 of the gene results in the substitution of Pro413 for Arg413 in the mutant protein. This mutation (R413P) results in negligible enzymatic activity when expressed in heterologous mammalian cells and is compatible with a classic PKU phenotype in the patient. Population genetic studies reveal that this mutation is tightly linked to restriction fragment length polymorphism haplotype 4, which is the predominant haplotype of the PAH locus in the Oriental population. It accounts for 13.8% of northern Chinese and 27% of Japanese PKU alleles, but it is rare in southern Chinese (2.2%) and is absent in the Caucasian population. The data demonstrate unambiguously that the mutation occurred after racial divergence of Orientals and Caucasians and suggest that the allele has spread throughout the Orient by a founder effect. Previous protein polymorphism studies in eastern Asia have led to the hypothesis that northern Mongoloids represented a founding population in Asia. The results are compatible with this hypothesis in that the PKU mutation might have occurred in northern Mongoloids and subsequently spread to the Chinese and Japanese populations

  15. EFFECTS OF MUTATIONS IN THE POLYMERASE GENE OF HEPATITIS B VIRUS GENOME ON LAMIVUDINE THERAPY

    韩永年; 张欣欣; 陆志檬; 张东华

    2001-01-01

    Objective To explore the effects of mutations in tyrosine-methionine-aspartic acid-aspartic acid (YMDD) motif of the polymerase in the hepatitis B virus ( HBV) genome on lamivudine antiviral therapy. Methods Partial HBV DNA segment containing the YMDD motif in the P gene was obtained through amplification by polymerase chain reaction ( PCR ) from 19 chronic hepatitis B patients with serum HBV DNA positive at the 48th week treatment with lamivudine and subjected to automatic sequencing. Influences of variants with YMDD mutations on lamivudine therapy were seen by observing the dynamic changes of serum HBV DNA and ALT levels. Results Serum HBV DNA breakthrough was found in 3 out of 10 individuals with detection of the YMDD mutations at the 48th week and in 5 at the 52th week, 2 of the 5 patients accompanied by serum ALT re-elevation, whereas of 9 subjects without YMDD mutations, 2 experienced an HBV DNA breakthrough at the 48th week and 1 of them had a conversion from HBV DNA positive to negative at the 52th week. Patients with detectable HBV DNA level had a fluctuating level of serum ALT all time during the treatment. Conclusion Detection of mutations in the YMDD motif of polyrnerase gene in HBV genome during the lamivudine therapy will be helpful to monitoring its therapeutic outcomes.

  16. The observed human sperm mutation frequency cannot explain the achondroplasia paternal age effect

    Tiemann-Boege, Irene; Navidi, William; Grewal, Raji; Cohn, Dan; Eskenazi, Brenda; Wyrobek, Andrew J.; Arnheim, Norman

    2002-01-01

    The lifelong spermatogonial stem cell divisions unique to male germ cell production are thought to contribute to a higher mutation frequency in males. The fact that certain de novo human genetic conditions (e.g., achondroplasia) increase in incidence with the age of the father is consistent with this idea. Although it is assumed that the paternal age effect is the result of an increasing frequency of mutant sperm as a man grows older, no direct molecular measurement of the germ-line mutation ...

  17. Mutation Testing for Effective Verification of Digital Components of Physical Systems

    Kushik, N. G.; Evtushenko, N. V.; Torgaev, S. N.

    2015-12-01

    Digital components of modern physical systems are often designed applying circuitry solutions based on the field programmable gate array technology (FPGA). Such (embedded) digital components should be carefully tested. In this paper, an approach for the verification of digital physical system components based on mutation testing is proposed. The reference description of the behavior of a digital component in the hardware description language (HDL) is mutated by introducing into it the most probable errors and, unlike mutants in high-level programming languages, the corresponding test case is effectively derived based on a comparison of special scalable representations of the specification and the constructed mutant using various logic synthesis and verification systems.

  18. The effects of maternal irradiation during adulthood on mutation induction and transgenerational instability in mice

    Abouzeid Ali, Hamdy E. [Department of Genetics, University of Leicester, University Road, Leicester LE1 7RH (United Kingdom); Radiobiological Applications Department, Nuclear Research Centre, Atomic Energy Authority, Cairo (Egypt); Barber, Ruth C. [Department of Genetics, University of Leicester, University Road, Leicester LE1 7RH (United Kingdom); Dubrova, Yuri E., E-mail: yed2@le.ac.uk [Department of Genetics, University of Leicester, University Road, Leicester LE1 7RH (United Kingdom)

    2012-04-01

    The long-term genetic effects of maternal irradiation remain poorly understood. To establish the effects of radiation exposure on mutation induction in the germline of directly exposed females and the possibility of transgenerational effects in their non-exposed offspring, adult female BALB/c and CBA/Ca mice were given 1 Gy of acute X-rays and mated with control males. The frequency of mutation at expanded simple tandem repeat (ESTR) loci in the germline of directly exposed females did not differ from that of controls. Using a single-molecule PCR approach, ESTR mutation frequency was also established for both germline and somatic tissues in the first-generation offspring of irradiated parents. While the frequency of ESTR mutation in the offspring of irradiated males was significantly elevated, maternal irradiation did not affect stability in their F{sub 1} offspring. Considering these data and the results of our previous study, we propose that, in sharp contrast to paternal exposure to ionising radiation, the transgenerational effects of maternal high-dose acute irradiation are likely to be negligible.

  19. Additive effect of propofol and fentanyl precipitating cardiogenic shock

    AC Jesudoss Prabhakaran

    2013-01-01

    Full Text Available The intravenous administration of propofol and fentanyl has become a common practice in a variety of clinical settings including outpatient dermatologic, cosmetic and oral surgery. The combination provides both systematic sedation and analgesia with low incidence of unwanted side effects. The cardiogenic shock is very uncommon in healthy individuals. The cardiovascular depressive effect of propofol and fentanyl has been well established, but the development of cardiogenic shock is very rare when these drugs are used together. Hence the awareness of this effect is advantageous to the patients undergoing such surgeries

  20. Effects of an additional dimension in the Young experiment

    Barros, Allan Kardec

    2015-01-01

    The results of the Young experiment can be analyzed either by classical or Quantum Physics. The later one though leads to a more complete interpretation, based on two different patterns that appear when one works either with single or double slits. Here we show that the two patterns can be derived from a single principle, in the context of General Relativity, if one assumes an additional spatial dimension to the four known today. The found equations yield the same results as those in Quantum Mechanics.

  1. Effects of an additional dimension in the Young experiment

    The results of the Young experiment can be analyzed either by classical or Quantum Physics. The later one though leads to a more complete interpretation, based on two different patterns that appear when one works either with single or double slits. Here we show that the two patterns can be derived from a single principle, in the context of General Relativity, if one assumes an additional spatial dimension to the four known today. The found equations yield the same results as those in Quantum Mechanics

  2. Effects of an additional dimension in the Young experiment

    Barros, Allan Kardec, E-mail: allan@elo.com.br

    2015-09-15

    The results of the Young experiment can be analyzed either by classical or Quantum Physics. The later one though leads to a more complete interpretation, based on two different patterns that appear when one works either with single or double slits. Here we show that the two patterns can be derived from a single principle, in the context of General Relativity, if one assumes an additional spatial dimension to the four known today. The found equations yield the same results as those in Quantum Mechanics.

  3. Additive effect of propofol and fentanyl precipitating cardiogenic shock

    AC Jesudoss Prabhakaran

    2013-01-01

    The intravenous administration of propofol and fentanyl has become a common practice in a variety of clinical settings including outpatient dermatologic, cosmetic and oral surgery. The combination provides both systematic sedation and analgesia with low incidence of unwanted side effects. The cardiogenic shock is very uncommon in healthy individuals. The cardiovascular depressive effect of propofol and fentanyl has been well established, but the development of cardiogenic shock is very rare w...

  4. Effect of hydrogen addition on autoignited methane lifted flames

    Choin, Byung Chul

    2012-01-01

    Autoignited lifted flames in laminar jets with hydrogen-enriched methane fuels have been investigated experimentally in heated coflow air. The results showed that the autoignited lifted flame of the methane/hydrogen mixture, which had an initial temperature over 920 K, the threshold temperature for autoignition in methane jets, exhibited features typical of either a tribrachial edge or mild combustion depending on fuel mole fraction and the liftoff height increased with jet velocity. The liftoff height in the hydrogen-assisted autoignition regime was dependent on the square of the adiabatic ignition delay time for the addition of small amounts of hydrogen, as was the case for pure methane jets. When the initial temperature was below 920 K, where the methane fuel did not show autoignition behavior, the flame was autoignited by the addition of hydrogen, which is an ignition improver. The liftoff height demonstrated a unique feature in that it decreased nonlinearly as the jet velocity increased. The differential diffusion of hydrogen is expected to play a crucial role in the decrease in the liftoff height with increasing jet velocity.

  5. Assessing the effects of Aedes aegypti kdr mutations on pyrethroid resistance and its fitness cost.

    Luiz Paulo Brito

    Full Text Available Pyrethroids are the most used insecticide class worldwide. They target the voltage gated sodium channel (NaV, inducing the knockdown effect. In Aedes aegypti, the main dengue vector, the AaNaV substitutions Val1016Ile and Phe1534Cys are the most important knockdown resistance (kdr mutations. We evaluated the fitness cost of these kdr mutations related to distinct aspects of development and reproduction, in the absence of any other major resistance mechanism. To accomplish this, we initially set up 68 crosses with mosquitoes from a natural population. Allele-specific PCR revealed that one couple, the one originating the CIT-32 strain, had both parents homozygous for both kdr mutations. However, this pyrethroid resistant strain also presented high levels of detoxifying enzymes, which synergistically account for resistance, as revealed by biological and biochemical assays. Therefore, we carried out backcrosses between CIT-32 and Rockefeller (an insecticide susceptible strain for eight generations in order to bring the kdr mutation into a susceptible genetic background. This new strain, named Rock-kdr, was highly resistant to pyrethroid and presented reduced alteration of detoxifying activity. Fitness of the Rock-kdr was then evaluated in comparison with Rockefeller. In this strain, larval development took longer, adults had an increased locomotor activity, fewer females laid eggs, and produced a lower number of eggs. Under an inter-strain competition scenario, the Rock-kdr larvae developed even slower. Moreover, when Rockefeller and Rock-kdr were reared together in population cage experiments during 15 generations in absence of insecticide, the mutant allele decreased in frequency. These results strongly suggest that the Ae. aegypti kdr mutations have a high fitness cost. Therefore, enhanced surveillance for resistance should be priority in localities where the kdr mutation is found before new adaptive alleles can be selected for diminishing the

  6. Human immunodeficiency virus type 1 integrase: effect on viral replication of mutations at highly conserved residues.

    Cannon, P M; Wilson, W; Byles, E; Kingsman, S M; Kingsman, A J

    1994-01-01

    Sequence comparisons of the integrase (IN) proteins from different retroviruses have identified several highly conserved residues. We have introduced mutations at 16 of these sites into the integrase gene of human immunodeficiency virus type 1 and analyzed the phenotypes of the resulting viruses. The viruses were all normal for p24 content and reverse transcriptase activity. In addition, all of the mutants could infect T-cell lines and undergo reverse transcription, as assessed by PCR analysi...

  7. Effective face recognition using bag of features with additive kernels

    Yang, Shicai; Bebis, George; Chu, Yongjie; Zhao, Lindu

    2016-01-01

    In past decades, many techniques have been used to improve face recognition performance. The most common and well-studied ways are to use the whole face image to build a subspace based on the reduction of dimensionality. Differing from methods above, we consider face recognition as an image classification problem. The face images of the same person are considered to fall into the same category. Each category and each face image could be both represented by a simple pyramid histogram. Spatial dense scale-invariant feature transform features and bag of features method are used to build categories and face representations. In an effort to make the method more efficient, a linear support vector machine solver, Pegasos, is used for the classification in the kernel space with additive kernels instead of nonlinear SVMs. Our experimental results demonstrate that the proposed method can achieve very high recognition accuracy on the ORL, YALE, and FERET databases.

  8. Effect of B addition to hypereutectic Ti-based alloys

    Louzguina-Luzgina, Larissa V. [Institute for Materials Research, Tohoku University, Katahira 2-1-1, Aoba-Ku, Sendai 980-8577 (Japan); Louzguine-Luzgin, Dmitri V. [WPI Advanced Institute for Materials Research, Tohoku University, Katahira 2-1-1, Aoba-Ku, Sendai 980-8577 (Japan)], E-mail: dml@imr.tohoku.ac.jp; Inoue, Akihisa [WPI Advanced Institute for Materials Research, Tohoku University, Katahira 2-1-1, Aoba-Ku, Sendai 980-8577 (Japan)

    2009-04-17

    The structure and mechanical properties of Ti-Fe-B and Ti-Fe-Co-B alloys produced in the shape of the arc-melted ingots of about 25 mm diameter and 10 mm height are studied. The hypereutectic alloys showed excellent compressive mechanical properties. The structures of the high-strength and ductile hypereutectic alloys studied by X-ray diffractometry and scanning electron microscopy were found to consist of the primary cubic cP2 intermetallic compound (TiFe-phase or a solid solution on its base) and a dispersed eutectic consisting of this cP2 intermetallic compound + BCC cI2 {beta}-Ti supersaturated solid solution phase. The addition of B increased mechanical strength. Si causes embrittlement owing to the formation of alternative intermetallic compounds. The structure and deformation behaviour were studied.

  9. Effect of dabrafenib on melanoma cell lines harbouring the BRAFV600D/R mutations

    Conventional therapeutic agents are largely unsatisfactory into the treatment of malignant melanoma. Recently, an innovative approach based on inhibitors of the mutated BRAF gene (which represents the most prevalent alteration in melanoma patients) appears very promising from the clinical point of view. On this regard, a new compound, dabrafenib (GSK2118436), has been demonstrated to be effective in patients carrying the BRAFV600E/K mutations. We here tested dabrafenib for its capability to inhibit cell growth on primary melanoma cell lines, established from patients' tumour tissues and carrying the BRAFV600D/R mutations. Three melanoma cell lines were tested: M257 wild-type BRAF, LCP BRAFV600R and WM266 BRAFV600D. The MTT assays were performed using standardized approaches. To evaluate the inhibition of MAPK pathway and the consequent inhibition of cellular proliferation, the phosphorylation of ERK was examined by Western Blot analysis performed on total protein extracts from cell lines after treatment with dabrafenib. Our experiments demonstrated an effective action of Dabrafenib (GSK2118436) and the inhibition of MAPK pathway in melanoma cell lines carrying BRAFV600D/R mutations. These results could be helpful to enlarge the number of melanoma patients who may benefit of a more effective targeted treatment

  10. Effect of dabrafenib on melanoma cell lines harbouring the BRAFV600D/R mutations

    Gentilcore Giusy

    2013-01-01

    Full Text Available Abstract Background Conventional therapeutic agents are largely unsatisfactory into the treatment of malignant melanoma. Recently, an innovative approach based on inhibitors of the mutated BRAF gene (which represents the most prevalent alteration in melanoma patients appears very promising from the clinical point of view. On this regard, a new compound, dabrafenib (GSK2118436, has been demonstrated to be effective in patients carrying the BRAFV600E/K mutations. We here tested dabrafenib for its capability to inhibit cell growth on primary melanoma cell lines, established from patients' tumour tissues and carrying the BRAFV600D/R mutations. Methods Three melanoma cell lines were tested: M257 wild-type BRAF, LCP BRAFV600R and WM266 BRAFV600D. The MTT assays were performed using standardized approaches. To evaluate the inhibition of MAPK pathway and the consequent inhibition of cellular proliferation, the phosphorylation of ERK was examined by Western Blot analysis performed on total protein extracts from cell lines after treatment with dabrafenib. Results Our experiments demonstrated an effective action of Dabrafenib (GSK2118436 and the inhibition of MAPK pathway in melanoma cell lines carrying BRAFV600D/R mutations. Conclusion These results could be helpful to enlarge the number of melanoma patients who may benefit of a more effective targeted treatment.

  11. Inverse dose-rate effect for mutation induction by γ-rays in human lymphoblasts

    In order to define further the effects of differences in recombinational proficiency on cell survival and mutation by ionizing radiation, we exposed the syngenic cell lines TK6 and WTK1 to continuous low dose-rate γ-irradiation. We previously demonstrated that acute X-ray exposure results in lower survival and lower mutation induction at both the thymidine kinase (tk) and the hypoxanthine-guanine phosphoribosyltransferase (hprt) loci in TK6 cells compared with WTK1 cells. These differences were attributed in part to reduced levels of recombination in the TK6 line relative to WTK1. Using a low dose rate 137Cs irradiator, we exposed asynchronous growing populations of these cells to γ-rays at 14.3, 6.7 and 2.7 cGy/h. Both cell lines exhibited a dose-rate effect on survival. Compared with acute doses, the low dose-rates also protected against mutation induction at the hrpt locus in WTK1, but protection was inversely related to dose-rate. There was also a slight inverse dose-rate effect in TK6, with mutation induction at the lowest dose-rate exceeding that at acute exposures. (Author)

  12. Effect of ethanol fuel additive on diesel emissions.; TOPICAL

    Engine-out emissions from a Volkswagen model TDI engine were measured for three different fuels: neat diesel fuel, a blend of diesel fuel and additives containing 10% ethanol, and a blend of diesel fuel and additives containing 15% ethanol. The test matrix covered five speeds from 1,320 to 3,000 rpm, five torques from 15 Nm to maximum plus the 900-rpm idle condition, and most of the points in the FTP-75 and US-06 vehicle tests. Emissions of particulate matter (PM), nitrogen oxides (NO(sub x)), unburned hydrocarbons (HCs), and carbon monoxide (CO) were measured at each point, as were fuel consumption, exhaust oxygen, and carbon dioxide output. PM emissions were reduced up to 75% when ethanol-diesel blends were used instead of neat diesel fuel. Significant reductions in PM emissions occurred over one-half to two-thirds of the test matrix. NO(sub x) emissions were reduced by up to 84%. Although the regions of reduced NO(sub x) emissions were much smaller than the regions of reduced PM emissions, there was considerable overlap between the two regions where PM emissions were reduced by up to 75% and NO(sub x) emissions were reduced by up to 84%. Such simultaneous reduction of both PM and NO(sub x) emissions would be difficult to achieve by any other means. HC and CO emissions were also reduced in the regions of reduced PM and NO(sub x) emissions that overlapped. Because the ethanol-diesel blends contain less energy on both a per-unit-mass basis and a per-unit-volume basis, there was a reduction in maximum torque of up to 10% and an increase in brake-specific fuel consumption of up to 7% when these blends were used

  13. The biological effects and clinical implications of BRCA mutations: where do we go from here?

    Stoppa-Lyonnet, Dominique

    2016-09-01

    BRCA1 and BRCA2 are tumour-suppressor genes encoding proteins that are essential for the repair of DNA double-strand breaks by homologous recombination (HR). Cells that lack either BRCA1 or BRCA2 repair these lesions by alternative, more error-prone mechanisms. Individuals carrying germline pathogenic mutations in BRCA1 or BRCA2 are at highly elevated risk of developing breast and/or ovarian cancer. Genetic testing for germline pathogenic mutations in BRCA1 and BRCA2 has proved to be a valuable tool for determining eligibility for cancer screening and prevention programmes. In view of increasing evidence that the HR DNA repair pathway can also be disrupted by sequence variants in other genes, screening for other BRCA-like defects has potential implications for patient care. Additionally, there is a growing argument for directly testing tumours for pathogenic mutations in BRCA1, BRCA2 and other genes involved in HR-DNA repair as inactivation of these genes may be strictly somatic. Tumours in which HR-DNA repair is altered are most likely to respond to emerging targeted therapies, such as inhibitors of poly-ADP ribose polymerase. This review highlights the biological role of pathogenic BRCA mutations and other associated defects in DNA damage repair mechanisms in breast and ovarian cancer, with particular focus on implications for patient management strategies. PMID:27514841

  14. Joint effects of heavy metal binary mixtures on seed germination, root and shoot growth, bacterial bioluminescence, and gene mutation

    In Chul Kong

    2013-01-01

    This investigation was to assess the joint effects of metal binary mixtures on seed germination,root and shoot growth,bacterial bioluminescence,and gene mutation based on the one toxic unit (1 TU) approach.Different sensitivities and orders of toxicity of metal mixtures were observed among the bioassays.In general,mostly additive or antagonistic effects were observed,while almost no synergistic effects by the binary metal mixtures in all bioassays.Therefore,the combined effects of heavy metals in the different bioassays were difficult to generalize since they were dependent on both chemical type and the organism used in each bioassay.However,these results indicate that a battery of bioassays with mixture chemicals as opposed to just a single assay with single metal is a better strategy for the bioassessment of environmental pollutants.

  15. Proceedings of the 8th workshop on plant mutation breeding. Effective use of physical/chemical mutagens

    Kume, Tamikazu; Watanabe, Kazuo; Tano, Shigemitsu (eds.) [Japan Atomic Energy Research Inst., Takasaki, Gunma (Japan). Takasaki Radiation Chemistry Research Establishment

    2001-03-01

    The Workshop on Plant Mutation Breeding of FNCA (Forum for Nuclear Cooperation in Asia), was held on 9-13 October 2000 in Hanoi, Vietnam. The Workshop was co-sponsored by the Science and Technology Agency (STA), the Ministry of Science, Technology and Environment (MOSTE of Vietnam) and the Ministry of Agriculture and Rural Development (MARD of Vietnam) in cooperation with the Ministry of Agriculture, Forestry and Fisheries (MAFF), National Institute of Agrobiological Resources (NIAR of Vietnam), the Japan Atomic Industrial Forum (JAIF) and Japan Atomic Energy Research Institute (JAERI). Two Scientists, a Project Leader and an expert on methodology for plant/crop mutation breeding, participated from each of the member countries, i.e. China, Indonesia, Malaysia, the Philippines, Thailand, Vietnam and Japan. Also attending the Workshop were, one participant from Korea, seven participants from both Japan and Vietnam. The number of the participants in the Workshop totalled about sixty people including guests and observers. Sixteen papers including eight invited papers on the current status of methodology for plant/crop mutation breeding in the participating countries were presented. Discussions were focused on the subject concerning 'Effective Use of Physical/Chemical Mutagens', as well as a detailed report on the current status of research in each participating country. In addition, the topics of developing a mutant breeding database, an information exchange for plant/crop mutation breeding, and more tightly bound international co-operative research in the near future were also high on the agenda. This proceeding compiles the invited and contributed papers that were submitted from the speakers. (author)

  16. Proceedings of the 8th workshop on plant mutation breeding. Effective use of physical/chemical mutagens

    The Workshop on Plant Mutation Breeding of FNCA (Forum for Nuclear Cooperation in Asia), was held on 9-13 October 2000 in Hanoi, Vietnam. The Workshop was co-sponsored by the Science and Technology Agency (STA), the Ministry of Science, Technology and Environment (MOSTE of Vietnam) and the Ministry of Agriculture and Rural Development (MARD of Vietnam) in cooperation with the Ministry of Agriculture, Forestry and Fisheries (MAFF), National Institute of Agrobiological Resources (NIAR of Vietnam), the Japan Atomic Industrial Forum (JAIF) and Japan Atomic Energy Research Institute (JAERI). Two Scientists, a Project Leader and an expert on methodology for plant/crop mutation breeding, participated from each of the member countries, i.e. China, Indonesia, Malaysia, the Philippines, Thailand, Vietnam and Japan. Also attending the Workshop were, one participant from Korea, seven participants from both Japan and Vietnam. The number of the participants in the Workshop totalled about sixty people including guests and observers. Sixteen papers including eight invited papers on the current status of methodology for plant/crop mutation breeding in the participating countries were presented. Discussions were focused on the subject concerning 'Effective Use of Physical/Chemical Mutagens', as well as a detailed report on the current status of research in each participating country. In addition, the topics of developing a mutant breeding database, an information exchange for plant/crop mutation breeding, and more tightly bound international co-operative research in the near future were also high on the agenda. This proceeding compiles the invited and contributed papers that were submitted from the speakers. (author)

  17. Measuring epistasis in fitness landscapes: The correlation of fitness effects of mutations.

    Ferretti, Luca; Schmiegelt, Benjamin; Weinreich, Daniel; Yamauchi, Atsushi; Kobayashi, Yutaka; Tajima, Fumio; Achaz, Guillaume

    2016-05-01

    Genotypic fitness landscapes are constructed by assessing the fitness of all possible combinations of a given number of mutations. In the last years, several experimental fitness landscapes have been completely resolved. As fitness landscapes are high-dimensional, simple measures of their structure are used as statistics in empirical applications. Epistasis is one of the most relevant features of fitness landscapes. Here we propose a new natural measure of the amount of epistasis based on the correlation of fitness effects of mutations. This measure has a natural interpretation, captures well the interaction between mutations and can be obtained analytically for most landscape models. We discuss how this measure is related to previous measures of epistasis (number of peaks, roughness/slope, fraction of sign epistasis, Fourier-Walsh spectrum) and how it can be easily extended to landscapes with missing data or with fitness ranks only. Furthermore, the dependence of the correlation of fitness effects on mutational distance contains interesting information about the patterns of epistasis. This dependence can be used to uncover the amount and nature of epistatic interactions in a landscape or to discriminate between different landscape models. PMID:26854875

  18. The Mutation Breeding and Mutagenic Effect of Air Plasma on Penicillium Chrysogenum

    桂芳; 王辉; 王鹏; 刘会; 蔡晓春; 胡以华; 袁成凌; 郑之明

    2012-01-01

    Low temperature air plasma was used as the mutation tool for penicillin-producing strain Penicillium chrysogenum. The discharge conditions were RF power of 360 W, temperature of 40℃ in a sealed chamber, and pressure of 10 Pa to 30 Pa. The result showed that the kinetics of the survival rate followed a typical saddle-shaped curve. Based on a statistic analysis, at the treating duration of 10 min, the positive mutation rate was as high as 37.5% while the negative mutation rate was low. The colonial morphology changed obviously when the plasma treating duration reached or exceeded 45 min. After both primary and secondary screening, a mutant designated as aPc051310 with high productivity of penicillin was obtained, and a strong mutagenic effect on P. chrysogenurn was observed in the process. It was proved that after five generations, the mutant aPc051310 still exhibits a high productivity. All the results prove that the plasma mutation method could be developed as a convenient and effective tool to breed high-yield strains in the fermentation industry, while expanding the plasm application at the same time.

  19. Effect of extracellular calcium on the additive effect of theophylline on the cardiac response to catecholamine

    Shamkuwar Prashant

    2008-01-01

    Full Text Available At different extracellular calcium concentrations, the positive inotropic effect of isoproterenol and isoproterenol in combination with theophylline, a phosphodiesterase inhibitor have been evaluated in the isolated frog heart and the isolated guinea pig left atria to investigate whether extracellular calcium produces any effect on the additive effect of the theophylline on the cardiac response to catecholamine. Cumulative dose response study of isoproterenol and isoproterenol in presence of theophylline at different extracellular calcium concentration was performed. The study revealed an increase in additive effect of theophylline on the cardiac response to catecholamine with increase in extracellular calcium concentration, but increase in extracellular calcium concentration decreased the myocardial responsiveness to additive effect of theophylline and isoproterenol combination. The mechanism of positive inotropic effect of isoproterenol and in combination with theophylline involves increase in intracellular cAMP by different pathways and extracellular calcium produces positive inotropic effect by initiating the interaction between the contractile proteins actin and myosin. The study revealed that an increase in the concentration of extracellular calcium increased the additive effect of theophylline and isoproterenol combination, but a decrease in the myocardial responsiveness was observed.

  20. IMMUNOMODULATORY EFFECT OF PHYTO-ADDITIVES IN BROILER CHICKENS

    LAVINIA ŞTEF

    2013-12-01

    Full Text Available The experiment was been performed in the sector of Nutrition and Animal Feeding discipline from Timisoara Didactic Station, on a 6 week period, beginning with hatching and finishing with 42 days of age, on 120 broilers divided into four experimental variants, each of them with 30 individuals. In LEU group was incorporated essential oils of Satureja hortensis, Mentha piperita and Hyperici herba 250 mg in 1 kg combined fodder, in LEP group was included in combined fodder structure a plants premix in 2%, in LEUP group was incorporated plants premix 2% +250 mg essential oil of Satureja hortensis, Mentha piperita, Hyperici herba in 1 kg combined fodder. After seric lizozime quntification was observed an increase with 303.46% in LEPU group, followed by LEU with 200.14%, results who demonstrated the presence of an immunological stimulation in broiler chickens. Increased values of seric properdine were observed in LEPU group, with 210.45% more increased in comparison with LM group, followed by LEU group, demonstrating that the changing of unspecific immune effectors values took place like a result of a exogenous substance with immunomodulator effect. Was also observed an easy increase of limfocytes in LPU group, but not so important like in first two determinations, if the experiment will continue, these values maybe will be significant increased, taking into consideration that these increases become more evident after a period of time after stimulation.

  1. A novel SOD1-ALS mutation separates central and peripheral effects of mutant SOD1 toxicity.

    Joyce, Peter I; Mcgoldrick, Philip; Saccon, Rachele A; Weber, William; Fratta, Pietro; West, Steven J; Zhu, Ning; Carter, Sarah; Phatak, Vinaya; Stewart, Michelle; Simon, Michelle; Kumar, Saumya; Heise, Ines; Bros-Facer, Virginie; Dick, James; Corrochano, Silvia; Stanford, Macdonnell J; Luong, Tu Vinh; Nolan, Patrick M; Meyer, Timothy; Brandner, Sebastian; Bennett, David L H; Ozdinler, P Hande; Greensmith, Linda; Fisher, Elizabeth M C; Acevedo-Arozena, Abraham

    2015-04-01

    Transgenic mouse models expressing mutant superoxide dismutase 1 (SOD1) have been critical in furthering our understanding of amyotrophic lateral sclerosis (ALS). However, such models generally overexpress the mutant protein, which may give rise to phenotypes not directly relevant to the disorder. Here, we have analysed a novel mouse model that has a point mutation in the endogenous mouse Sod1 gene; this mutation is identical to a pathological change in human familial ALS (fALS) which results in a D83G change in SOD1 protein. Homozgous Sod1(D83G/D83G) mice develop progressive degeneration of lower (LMN) and upper motor neurons, likely due to the same unknown toxic gain of function as occurs in human fALS cases, but intriguingly LMN cell death appears to stop in early adulthood and the mice do not become paralyzed. The D83 residue coordinates zinc binding, and the D83G mutation results in loss of dismutase activity and SOD1 protein instability. As a result, Sod1(D83G/D83G) mice also phenocopy the distal axonopathy and hepatocellular carcinoma found in Sod1 null mice (Sod1(-/-)). These unique mice allow us to further our understanding of ALS by separating the central motor neuron body degeneration and the peripheral effects from a fALS mutation expressed at endogenous levels. PMID:25468678

  2. The Potential Negative Effects of Interleukin 1 B in Multiple Sclerosis Patients with MEFV Mutation

    Mahmut Alpayci

    2013-10-01

    Full Text Available Multiple sclerosis patients, who are carriers of MEditerranean FeVer (MEFV gene mutation, have faster progression than the non-carriers. However, its underlying mechanism is not well understood. This article proposes the potential role of interleukin-1β (IL-1β that may be responsible for this rapid progression. Mutations in MEFV, the gene encoding for protein pyrin, cause familial Mediterranean fever, lead to gain of pyrin function, resulting in inappropriate IL-1β release. Interleukin-1β is a major mediator of systemic inflammation and fever, and also it contributes to permeability of the blood-brain barrier in active lesions of multiple sclerosis. Moreover, IL-1β promotes apoptosis of neurons and oligodendrocytes that produce the myelin sheath, which insulates axons. Thus, inflammatory damage, the blood-brain barrier disfunction, effects of fever on the central nervous system (or Uhthoff’s phenomenon, and apoptosis of neurons and oligodendrocytes, which play an important role in the pathogenesis and clinical course of multiple sclerosis, can be induced by increased activation and release of IL-1β in the presence of MEFV gene mutations. Therefore, screening for MEFV mutations in patients with multiple sclerosis and treatment planning with IL-1β targeting drugs for the carriers, may be a logical idea that will be a source of inspiration for scientific studies.

  3. Distinctive effects of nicotinic receptor intracellular-loop mutations associated with nocturnal frontal lobe epilepsy.

    Weltzin, Maegan M; Lindstrom, Jon M; Lukas, Ronald J; Whiteaker, Paul

    2016-03-01

    Previously characterized nicotinic acetylcholine receptor (nAChR) autosomal dominant nocturnal frontal lobe epilepsy (ADNFLE)-associated mutations are found in α2, α4 and β2 subunit transmembrane (TM) domains. They predominantly increase ACh potency and, for β2-subunit mutants, increase macroscopic currents. Two recently-identified mutations, α4(R336H) and β2(V337G), located in the intracellular cytoplasmic loop (C2) have been associated with non-familial NFLE. Effects of these mutations on α4β2-nAChR function and expression were studied for the first time, using two-electrode voltage clamp recordings in Xenopus laevis oocytes. Biased-ratio preparations elucidated the mutations' effects at alternate isoforms: high-sensitivity [HS; (α4)2(β2)3] or low-sensitivity [LS; (α4)3(β2)2] via 1:10 or 30:1 [α4:β2] cRNA injection ratios, respectively. An unbiased (1:1 [α4:β2] cRNA) injection ratio was also used to study potential shifts in isoform expression. α4(R336H)-containing receptors showed significant increases in maximal ACh-induced currents (Imax) in all preparations (140% increase compared to wild type control). β2(V337G)-containing receptors significantly increased Imax in the LS-favoring preparation (20% increase compared to control). Expression of either mutation consistently produced enrichment of HS-isoform expression in all preparations. α4β2-nAChR harboring either NFLE mutant subunit showed unchanged ACh, sazetidine-A, nicotine, cytisine and mecamylamine potency. However, both mutant subunits enhanced partial agonist efficacies in the LS-biased preparation. Using β2-subunit-specific [(125)I]mAb 295 immunolabeling, nAChR cell-surface expression was determined. Antibody binding studies revealed that the β2(V337G) mutation tended to reduce cell-surface expression, and function per receptor was significantly increased by either NFLE mutant subunit in HS-favoring preparations. These findings identify both common and differing features between

  4. Effects of mutations on the structure and function of silkworm type 1 acetylcholinesterase.

    Wang, B B; Li, F C; Xu, K Z; Ni, M; Hu, J S; Tian, J H; Li, Y Y; Shen, W D; Li, B

    2016-05-01

    AChE is the target of organophosphate (OP) and carbamate (CB) pesticides, and mutations in the gene can significantly reduce insects' sensitivity to these pesticides. Bombyx mori is highly sensitive to pesticides. To investigate the effects of mutations on AChE1 structure and function, we used a prokaryotic system to express B.mori wild type AChE1 (wAChE1) and mutant AChE1 (mAChE1) in this study. Active AChE1 proteins were obtained after refolding and purification, and wAChE1 and mAChE1 had similar activities. After incubation with 10(-6)M physostigmine and 10(-3)mg/mL phoxim, the remaining enzyme activity of mAChE1 was 4.42% and 8.86% higher than that of wAChE1's, respectively. Three-dimensional analysis of mutation AChE1 (mAChE1) revealed that the Ser and Ala side chains extended toward the central part of S285 with distances of just 2.80Å and 3.68Å, respectively, which changed the spatial structure of the active center and reduced its sensitivity to pesticides. These results indicated that the mutations altered the 3D structure of AChE1, which may affect the binding of physostigmine and phoxim to the serine residue at the active center, leading to reduced sensitivity. Our study helps understand the relationship between AChE1 mutations and pesticide resistance and provides a new direction for the cultivation of new pesticide-resistant varieties of B.mori. PMID:27017875

  5. The effect of antagonistic pleiotropy on the estimation of the average coefficient of dominance of deleterious mutations.

    Fernández, B; García-Dorado, A; Caballero, A

    2005-12-01

    We investigate the impact of antagonistic pleiotropy on the most widely used methods of estimation of the average coefficient of dominance of deleterious mutations from segregating populations. A proportion of the deleterious mutations affecting a given studied fitness component are assumed to have an advantageous effect on another one, generating overdominance on global fitness. Using diffusion approximations and transition matrix methods, we obtain the distribution of gene frequencies for nonpleiotropic and pleiotropic mutations in populations at the mutation-selection-drift balance. From these distributions we build homozygous and heterozygous chromosomes and assess the behavior of the estimators of dominance. A very small number of deleterious mutations with antagonistic pleiotropy produces substantial increases on the estimate of the average degree of dominance of mutations affecting the fitness component under study. For example, estimates are increased three- to fivefold when 2% of segregating loci are over-dominant for fitness. In contrast, strengthening pleiotropy, where pleiotropic effects are assumed to be also deleterious, has little effect on the estimates of the average degree of dominance, supporting previous results. The antagonistic pleiotropy model considered, applied under mutational parameters described in the literature, produces patterns for the distribution of chromosomal viabilities, levels of genetic variance, and homozygous mutation load generally consistent with those observed empirically for viability in Drosophila melanogaster. PMID:16118193

  6. The Effect of Mutation and Selection on Codon Adaptation in Escherichia coli Bacteriophage

    Chithambaram, Shivapriya; Prabhakaran, Ramanandan; Xia, Xuhua

    2014-01-01

    Studying phage codon adaptation is important not only for understanding the process of translation elongation, but also for reengineering phages for medical and industrial purposes. To evaluate the effect of mutation and selection on phage codon usage, we developed an index to measure selection imposed by host translation machinery, based on the difference in codon usage between all host genes and highly expressed host genes. We developed linear and nonlinear models to estimate the C→T mutati...

  7. Cochlear implantation effect on deaf children with gap junction protein beta 2 gene mutation

    KONG Ying; LIU Sha; WANG Su-ju; Li Shu-jing; LIANG Shuang

    2013-01-01

    Background The popularization and promotion of gene diagnosis technology makes it possible to detect deafness genes for children with congenital hearing impairment,and the proportion of gap junction protein beta 2 (GJB2) gene mutations in cochlear implant patients is 26.5% We did follow-up evaluation on auditory rehabilitation effect for all 31 deaf children with GJB2 gene mutation after cochlear implantation to provide a reference for such patients.Methods Application of “the genetic deafness gene chip detection kit” and “gene complete sequence analysis” were applied to conduct detection on common genetic deafness gene mutation hotspots of the hearing impaired children with cochlear implantation.To conduct auditory rehabilitation effect evaluation on all 31 cases of patients with GJB2 genetic deafness after 3,6 and 12 months of the operation respectively.The single factor repeated measure analysis of variance (ANOVA) was applied to analysis whether there were significant difference among the results of initial consonant of a Chinese syllable recognition at 3 different stages after the operation,the results of vowel of a Chinese syllable recognition at 3 different stages after the operation,and the results of two-syllable recognition at 3 different stages after the operation.Results The 235delC is the high-incidence mutational site in 31 cases of patients with GJB2 genetic deafness,and the total detection rate is up to 90.3% (28/31).There were significant differences in the initial consonant and the vowel of a Chinese syllable recognition rate,and the two-syllable recognition rates at 3,6,and 12 months after the operation (P<0.01).Conclusion Cochlear implantation is a safe and effective measure for auditory reconstruction,enabling patients with GJB2 hereditary severe sensorineural deafness to achieve auditory speech recognition effectively.

  8. The Effect of Post-Reproductive Lifespan on the Fixation Probability of Beneficial Mutations.

    Stefano Giaimo

    Full Text Available Post-reproductive lifespan is a common trait among mammals and is usually considered to be neutral; i.e. with no influence on population dynamics. Here, we explore the role of post-reproductive lifespan in the fixation probability of beneficial genetic variation. We compare two separate, stationary populations living in a constant environment that are equivalent except for the average time their respective members spend in the post-reproductive stage of life. Using a recently derived approximation, we show that fixation of a beneficial mutation is more likely in the population with greater post-reproductive longevity. This finding is surprising, as the population with more prolonged post-reproductive lifespan has smaller effective size and the classic population-genetic model would suggest that decreasing effective size reduces fixation chances of beneficial mutations. Yet, as we explain, in the age-structured case, when effective size gets smaller because of longer post-reproductive lifespan but census size is kept equal, a beneficial mutation has a higher likelihood to get fixed because it finds itself at higher initial frequency.

  9. Differential effects of radical scavengers on X-ray-induced mutation and cytotoxicity in human cells

    The cytotoxic and mutagenic effects of X irradiation on a human lymphoblast cell line were examined in the presence of two radioprotective agents which modulate damage to DNA. The cells were treated with X rays alone or in the presence of either dimethyl sulfoxide or cysteamine. Surviving fraction and mutation to trifluorothymidine resistance (tk locus) and to 6-thioguanine resistance (hgprt locus) were measured. Survival was enhanced when the cells were irradiated in the presence of dimethyl sulfoxide; the D0 rose from 58 to 107 rad. However, at both genetic loci the induced mutant fractions were identical in the presence or absence of dimethyl sulfoxide. Survival was enhanced to a greater degree when the cells were irradiated in the presence of cysteamine; the D0 rose from 58 to 200 rad. Cysteamine also protected the cells from X-ray-induced mutation; the frequencies of X-ray-induced mutation at both the tk and hgprt loci were reduced by 50-75%. No protective effects were observed unless dimethyl sulfoxide or cysteamine was present during irradiation. These findings are discussed in terms of the hypothesis that, unlike for cell killing, radiation-induced mutagenesis in human lymphoblast cells is not mediated by the actions of aqueous free radicals, but rather by the direct effects of ionizing radiation

  10. The impact on outcome of the addition of all-trans retinoic acid to intensive chemotherapy in younger patients with nonacute promyelocytic acute myeloid leukemia: overall results and results in genotypic subgroups defined by mutations in NPM1, FLT3, and CEBPA.

    Burnett, Alan K; Hills, Robert K; Green, Claire; Jenkinson, Sarah; Koo, Kenneth; Patel, Yashma; Guy, Carol; Gilkes, Amanda; Milligan, Donald W; Goldstone, Anthony H; Prentice, Archibald G; Wheatley, Keith; Linch, David C; Gale, Rosemary E

    2010-02-01

    We investigated the benefit of adding all-trans retinoic acid (ATRA) to chemotherapy for younger patients with nonacute promyelocytic acute myeloid leukemia and high-risk myelodysplastic syndrome, and considered interactions between treatment and molecular markers. Overall, 1075 patients less than 60 years of age were randomized to receive or not receive ATRA in addition to daunorubicin/Ara-C/thioguanine chemotherapy with Ara-C at standard or double standard dose. There were data on FLT3 internal tandem duplications and NPM1 mutations (n = 592), CEBPA mutations (n = 423), and MN1 expression (n = 195). The complete remission rate was 68% with complete remission with incomplete count recovery in an additional 16%; 8-year overall survival was 32%. There was no significant treatment effect for any outcome, with no significant interactions between treatment and demographics, or cytarabine randomization. Importantly, there were no interactions by FLT3/internal tandem duplications, NPM1, or CEBPA mutation. There was a suggestion that ATRA reduced relapse in patients with lower MN1 levels, but no significant effect on overall survival. Results were consistent when restricted to patients with normal karyotype. ATRA has no overall effect on treatment outcomes in this group of patients. The study did not identify any subgroup of patients likely to derive a significant survival benefit from the addition of ATRA to chemotherapy. PMID:19965647

  11. Multiple oncogenic mutations related to targeted therapy in nasopharyngeal carcinoma

    Jian-Wei Zhang; Hong-Yuan Zhao; Yu-Xiang Ma; Zhi-Huang Hu; Pei-Yu Huang; Li Zhang; Tao Qin; Shao-Dong Hong; Jing Zhang; Wen-Feng Fang; Yuan-Yuan Zhao; Yun-Peng Yang; Cong Xue; Yan Huang

    2015-01-01

    Introduction:An increasing number of targeted drugs have been tested for the treatment of nasopharyngeal carcinoma (NPC). However, targeted therapy-related oncogenic mutations have not been fully evaluated. This study aimed to detect targeted therapy-related oncogenic mutations in NPC and to determine which targeted therapy might be potentially effective in treating NPC. Methods:By using the SNaPshot assay, a rapid detection method, 19 mutation hotspots in 6 targeted therapy-related oncogenes were examined in 70 NPC patients. The associations between oncogenic mutations and clinicopathologic factors were analyzed. Results:Among 70 patients, 12 (17.1%) had mutations in 5 oncogenes:7 (10.0%) had v-kit Hardy-Zuckerman 4 feline sarcoma viral oncogene homolog (KIT) mutation, 2 (2.8%) had epidermal growth factor receptor (EGFR) mutation, 1 (1.4%) had phosphatidylinositol-4,5-bisphosphate 3-kinase, catalytic subunit alpha (PIK3CA) mutation, 1 (1.4%) had Kirsten rat sarcoma viral oncogene homolog (KRAS) mutation, and 1 (1.4%) had simultaneous EGFR and v-Raf murine sarcoma viral oncogene homolog B1 (BRAF) mutations. No significant differences were observed between oncogenic mutations and clinicopathologic characteristics. Additionally, these oncogenic mutations were not associated with tumor recurrence and metastasis. Conclusions:Oncogenic mutations are present in NPC patients. The efficacy of targeted drugs on patients with the related oncogenic mutations requires further validation.

  12. Direct Estimate of the Spontaneous Mutation Rate Uncovers the Effects of Drift and Recombination in the Chlamydomonas reinhardtii Plastid Genome.

    Ness, Rob W; Kraemer, Susanne A; Colegrave, Nick; Keightley, Peter D

    2016-03-01

    Plastids perform crucial cellular functions, including photosynthesis, across a wide variety of eukaryotes. Since endosymbiosis, plastids have maintained independent genomes that now display a wide diversity of gene content, genome structure, gene regulation mechanisms, and transmission modes. The evolution of plastid genomes depends on an input of de novo mutation, but our knowledge of mutation in the plastid is limited to indirect inference from patterns of DNA divergence between species. Here, we use a mutation accumulation experiment, where selection acting on mutations is rendered ineffective, combined with whole-plastid genome sequencing to directly characterize de novo mutation in Chlamydomonas reinhardtii. We show that the mutation rates of the plastid and nuclear genomes are similar, but that the base spectra of mutations differ significantly. We integrate our measure of the mutation rate with a population genomic data set of 20 individuals, and show that the plastid genome is subject to substantially stronger genetic drift than the nuclear genome. We also show that high levels of linkage disequilibrium in the plastid genome are not due to restricted recombination, but are instead a consequence of increased genetic drift. One likely explanation for increased drift in the plastid genome is that there are stronger effects of genetic hitchhiking. The presence of recombination in the plastid is consistent with laboratory studies in C. reinhardtii and demonstrates that although the plastid genome is thought to be uniparentally inherited, it recombines in nature at a rate similar to the nuclear genome. PMID:26615203

  13. Effects of short-term spontaneous mutation accumulation for life history traits in grape phylloxera, Daktulosphaira vitifoliae.

    Downie, D A

    2003-11-01

    Mutation is the source of all genetic variation, but rate of input and effects of new mutations for phenotypic traits related to fitness and the role they play in the maintenance of genetic variation are still subject to controversy. These parameters are important in models of the evolution of sex and recombination, the persistence of asexual populations, and the extinction of small populations. Most estimates have come from a few model organisms. Here, mutation accumulation experiments were conducted with three clones of grape phylloxera, Daktulosphaira vitifoliae Fitch, a gall forming herbivore and pest of grapes, to estimate the rate of input and effects of spontaneous mutation on life history traits. This is perhaps the first such experiment using a non-model organism of economic importance. Significant heritable genetic variation accrued in one of three sets of lines for one of four traits measured, and deleterious effects of mutation were found for two of four traits in two of the three sets of lines. Estimates of the parameters by the Bateman-Mukai (BM) method were within the range found in previous studies but at the lower end for genomic mutation rate, U approximately 0.023 and mutational variance, V(M) approximately 0.0003, the upper end for average heterozygous effect, alpha, of approximately -0.11, and on the order of previous estimates for mutational heritability, hM approximately 0.007. Under a model of equal effects of mutations, maximum likelihood (ML) estimates of U were slightly higher, and of alpha lower, than the BM estimates. Support limits were too large to provide much confidence in the ML estimates, however, and models of mutational effects assuming a gamma distribution of effects under different values of the shape parameter, beta, could not be distinguished though likelihoods tended to be lower at lower values of beta (more leptokurtic). Rapid accumulation of deleterious mutations suggest that for many pest species, adaptive response under

  14. Aromatase inhibiting and combined estrogenic effects of parabens and estrogenic effects of other additives in cosmetics

    There is concern widely on the increase in human exposure to exogenous (anti)estrogenic compounds. Typical are certain ingredients in cosmetic consumer products such as musks, phthalates and parabens. Monitoring a variety of human samples revealed that these ingredients, including the ones that generally are considered to undergo rapid metabolism, are present at low levels. In this in vitro research individual compounds and combinations of parabens and endogenous estradiol (E2) were investigated in the MCF-7 cell proliferation assay. The experimental design applied a concentration addition model (CA). Data were analyzed with the estrogen equivalency (EEQ) and method of isoboles approach. In addition, the catalytic inhibitory properties of parabens on an enzyme involved in a rate limiting step in steroid genesis (aromatase) were studied in human placental microsomes. Our results point to an additive estrogenic effect in a CA model for parabens. In addition, it was found that parabens inhibit aromatase. Noticeably, the effective levels in both our in vitro systems were far higher than the levels detected in human samples. However, estrogenic compounds may contribute in a cumulative way to the circulating estrogen burden. Our calculation for the extra estrogen burden due to exposure to parabens, phthalates and polycyclic musks indicates an insignificant estrogenic load relative to the endogenous or therapeutic estrogen burden

  15. Effects of track structure and cell inactivation on the calculation of heavy ion mutation rates in mammalian cells

    Cucinotta, F. A.; Wilson, J. W.; Shavers, M. R.; Katz, R.

    1996-01-01

    It has long been suggested that inactivation severely effects the probability of mutation by heavy ions in mammalian cells. Heavy ions have observed cross sections of inactivation that approach and sometimes exceed the geometric size of the cell nucleus in mammalian cells. In the track structure model of Katz the inactivation cross section is found by summing an inactivation probability over all impact parameters from the ion to the sensitive sites within the cell nucleus. The inactivation probability is evaluated using the dose-response of the system to gamma-rays and the radial dose of the ions and may be equal to unity at small impact parameters for some ions. We show how the effects of inactivation may be taken into account in the evaluation of the mutation cross sections from heavy ions in the track structure model through correlation of sites for gene mutation and cell inactivation. The model is fit to available data for HPRT mutations in Chinese hamster cells and good agreement is found. The resulting calculations qualitatively show that mutation cross sections for heavy ions display minima at velocities where inactivation cross sections display maxima. Also, calculations show the high probability of mutation by relativistic heavy ions due to the radial extension of ions track from delta-rays in agreement with the microlesion concept. The effects of inactivation on mutations rates make it very unlikely that a single parameter such as LET or Z*2/beta(2) can be used to specify radiation quality for heavy ion bombardment.

  16. Effect of point mutations on Herbaspirillum seropedicae NifA activity

    Aquino, B.; Stefanello, A.A.; Oliveira, M.A.S.; Pedrosa, F.O.; Souza, E.M.; Monteiro, R.A.; Chubatsu, L.S. [Departamento de Bioquímica e Biologia Molecular, Universidade Federal do Paraná, Curitiba, PR (Brazil)

    2015-07-10

    NifA is the transcriptional activator of the nif genes in Proteobacteria. It is usually regulated by nitrogen and oxygen, allowing biological nitrogen fixation to occur under appropriate conditions. NifA proteins have a typical three-domain structure, including a regulatory N-terminal GAF domain, which is involved in control by fixed nitrogen and not strictly required for activity, a catalytic AAA+ central domain, which catalyzes open complex formation, and a C-terminal domain involved in DNA-binding. In Herbaspirillum seropedicae, a β-proteobacterium capable of colonizing Graminae of agricultural importance, NifA regulation by ammonium involves its N-terminal GAF domain and the signal transduction protein GlnK. When the GAF domain is removed, the protein can still activate nif genes transcription; however, ammonium regulation is lost. In this work, we generated eight constructs resulting in point mutations in H. seropedicae NifA and analyzed their effect on nifH transcription in Escherichia coli and H. seropedicae. Mutations K22V, T160E, M161V, L172R, and A215D resulted in inactive proteins. Mutations Q216I and S220I produced partially active proteins with activity control similar to wild-type NifA. However, mutation G25E, located in the GAF domain, resulted in an active protein that did not require GlnK for activity and was partially sensitive to ammonium. This suggested that G25E may affect the negative interaction between the N-terminal GAF domain and the catalytic central domain under high ammonium concentrations, thus rendering the protein constitutively active, or that G25E could lead to a conformational change comparable with that when GlnK interacts with the GAF domain.

  17. Effect of point mutations on Herbaspirillum seropedicae NifA activity

    NifA is the transcriptional activator of the nif genes in Proteobacteria. It is usually regulated by nitrogen and oxygen, allowing biological nitrogen fixation to occur under appropriate conditions. NifA proteins have a typical three-domain structure, including a regulatory N-terminal GAF domain, which is involved in control by fixed nitrogen and not strictly required for activity, a catalytic AAA+ central domain, which catalyzes open complex formation, and a C-terminal domain involved in DNA-binding. In Herbaspirillum seropedicae, a β-proteobacterium capable of colonizing Graminae of agricultural importance, NifA regulation by ammonium involves its N-terminal GAF domain and the signal transduction protein GlnK. When the GAF domain is removed, the protein can still activate nif genes transcription; however, ammonium regulation is lost. In this work, we generated eight constructs resulting in point mutations in H. seropedicae NifA and analyzed their effect on nifH transcription in Escherichia coli and H. seropedicae. Mutations K22V, T160E, M161V, L172R, and A215D resulted in inactive proteins. Mutations Q216I and S220I produced partially active proteins with activity control similar to wild-type NifA. However, mutation G25E, located in the GAF domain, resulted in an active protein that did not require GlnK for activity and was partially sensitive to ammonium. This suggested that G25E may affect the negative interaction between the N-terminal GAF domain and the catalytic central domain under high ammonium concentrations, thus rendering the protein constitutively active, or that G25E could lead to a conformational change comparable with that when GlnK interacts with the GAF domain

  18. The use of Citrus tissue culture for mutation breeding. Effects of plant growth substances and gamma irradiation on embryogenesis

    An embryogenic callus subcultured from unfertilized ovules of the 'Shamouti' orange (Citrus sinensis) was established and is used for mutation-breeding. The callus is habituated and lines of differing embryogenic potential were established. The effect of growth substances and of gamma-irradiation on embryogenesis were studied. Auxins and cytokinins inhibited embryogenesis while inhibitors of auxin synthesis and a cytokinin antagonist significantly stimulate embryogenesis in an embryogenic line. A non-embryogenic callus line did not respond to these treatments. Stimulation of embryogenesis was observed when callus but not when the medium was irradiated. Age of callus prior to subculture and irradiation intensities modify irradiation induced embryogenesis by changing optimal dose range and radiosensitivity of the callus. Addition of IAA to unirradiated medium resulted in increased embryogenesis and greatly stimulated plantlet development in certain combinations of irradiation dose and IAA concentration. (author)

  19. The effects of lexA101, recB21, recF143 and uvrD3 mutations on liquid-holding recovery in ultraviolet-irradiated Escherichia coli K12 recA56

    Using an Escherichia coli K12 recA strain, we have tested the effects of incorporating additional mutations affecting deoxyribonucleic acid (DNA) repair on ultraviolet-radiation sensitivity and in the expression of liquid-holding recovery (LHR). (This laboratory had previously shown that a mutation at uvrA, uvrB or uvrC blocked LHR in a recA strain). In the recA56 background, an additional lexA101 mutation had no effect on UV-radiation sensitivity or LHR. The addition of a recB21 mutation to recA56 did not alter UV-radiation sensitivity, but greatly increased the rate of LHR. The recB gene product (exonuclease V) appears to act as a competitive inhibitor both of excision repair and of photoreactivation under liquid-holding (LH) conditions. The uvrD3 mutation increased the radiation sensitivity of a recA strain, and almost completely blocked LHR. The recA uvrD strain showed more DNA degradation and DNA double-strand breaks during LH than did the recA strain. Rhe recF143 mutation increased both UV-radiation sensitivity and LHR in a recA strain, suggesting that the recF gene product may also function in recA-independent pathways of DNA repair. (orig.)

  20. Effects of some natural extracts on tradescantia somatic cell pink mutation frequencies induced by gamma-ray

    This study deals with the effect of some natural extracts on the pink mutations induced by radiation in Tradescantia 4430 stamen hair cells. Inflorescence cuttings, with or without pretreatments of natural extracts for 3 hours, were exposed to 1 Gy of gamma ray. Comparisons were made on the basis of pooled data during the peak interval between the mean pink mutation frequencies of the two experimental groups. Pretreatments of FB or FB-I resulted in two-fold increases of the pink mutation frequencies, compared to those of control group. Synergism between certain fractions and radiation was a possible cause of increased DNA damage. On the other hand, the extract PG in proper concentrations significantly reduced the pink mutation frequencies (p<0.05). The result meant that PG had a protective effect on radiation-induced cell damage. Tradescantia proved to be an excellent biological model system for assessing the radiomodification effects of natural materials

  1. Effects of partial hepatectomy on induction of mutation frequency by gamma-rays in new HITEC mice

    Mutations induced in vivo by radiation were studied with a transgenic mouse strain, called New HITEC (Hypersensitive In vitro Test of Carcinogenecity), carrying the rpsL gene as a reporter for mutation detection. The wild-type rpsL gene and a gene inducing a kanamycin-resistant phenotype were placed on a pSSW plasmid shuttle vector, and were transfected into E. coli by electroporation after extraction from mouse genomic DNA. Transfected cells were plated on LB plates containing Kanamycine (Km) or Km plus Streptomycine (Sm). The ratio of the colony number on Km and Sm plates to that on Km plates is defined as the rpsL mutation frequency. We had previously investigated differences in mutation frequencies in the testis, spleen, liver, brain, and thymus using rpsL transgenic mice. However, there were some problems in the analysis with a high background mutation frequency. To solve this problem, a partial hepatectomy was tried to increase the mutation frequency detection. The mice were exposed to 3 Gy of gamma rays at 24, 40, 48, or 72 hours after the hepatectomy. Then, the liver was resected on day 7-10 after irradiation, and the mutation frequencies were analyzed. In the mice exposed 24 hours after hepatectomy, the mutation frequency increased approximately four times compared with that of the control mice. In the mice exposed 40, 48, or 72 hours after hepatectomy, the increase in mutation frequency was 2-3 times greater than that of the control mice. These results indicate that hepatectomy is effective in raising the mutation frequency along with the appropriate timing of irradiation

  2. The novel R347g pathogenic mutation of aromatic amino acid decarboxylase provides additional molecular insights into enzyme catalysis and deficiency.

    Montioli, Riccardo; Paiardini, Alessandro; Kurian, Manju A; Dindo, Mirco; Rossignoli, Giada; Heales, Simon J R; Pope, Simon; Voltattorni, Carla Borri; Bertoldi, Mariarita

    2016-06-01

    We report here a clinical case of a patient with a novel mutation (Arg347→Gly) in the gene encoding aromatic amino acid decarboxylase (AADC) that is associated with AADC deficiency. The variant R347G in the purified recombinant form exhibits, similarly to the pathogenic mutation R347Q previously studied, a 475-fold drop of kcat compared to the wild-type enzyme. In attempting to unravel the reason(s) for this catalytic defect, we have carried out bioinformatics analyses of the crystal structure of AADC-carbidopa complex with the modelled catalytic loop (residues 328-339). Arg347 appears to interact with Phe103, as well as with both Leu333 and Asp345. We have then prepared and characterized the artificial F103L, R347K and D345A mutants. F103L, D345A and R347K exhibit about 13-, 97-, and 345-fold kcat decrease compared to the wild-type AADC, respectively. However, unlike F103L, the R347G, R347K and R347Q mutants as well as the D345A variant appear to be more defective in catalysis than in protein folding. Moreover, the latter mutants, unlike the wild-type protein and the F103L variant, share a peculiar binding mode of dopa methyl ester consisting of formation of a quinonoid intermediate. This finding strongly suggests that their catalytic defects are mainly due to a misplacement of the substrate at the active site. Taken together, our results highlight the importance of the Arg347-Leu333-Asp345 hydrogen-bonds network in the catalysis of AADC and reveal the molecular basis for the pathogenicity of the variants R347. Following the above results, a therapeutic treatment for patients bearing the mutation R347G is proposed. PMID:26994895

  3. The Effect of Antagonistic Pleiotropy on the Estimation of the Average Coefficient of Dominance of Deleterious Mutations

    Fernández, B.; García-Dorado, A; Caballero, A.

    2005-01-01

    We investigate the impact of antagonistic pleiotropy on the most widely used methods of estimation of the average coefficient of dominance of deleterious mutations from segregating populations. A proportion of the deleterious mutations affecting a given studied fitness component are assumed to have an advantageous effect on another one, generating overdominance on global fitness. Using diffusion approximations and transition matrix methods, we obtain the distribution of gene frequencies for n...

  4. The additive and interactive effects of parenting and children's personality on externalizing behaviour

    Prinzie, P; Onghena, P; Hellinckx, W; Grietens, H; Ghesquiere, P; Colpin, H

    2003-01-01

    Parenting practices have been previously linked to childhood externalizing behaviour However little attention has been given to the potential effect of individual personality differences among children on this relation. The current study assesses the additive effects of children's personality charac

  5. Widespread non-additive and interaction effects within HLA loci modulate the risk of autoimmune diseases

    Lenz, Tobias L.; Deutsch, Aaron J.; Han, Buhm; Hu, Xinli; Okada, Yukinori; Eyre, Stephen; Knapp, Michael; Zhernakova, Alexandra; Huizinga, Tom W. J.; Abecasis, Gonçalo; Becker, Jessica; Boeckxstaens, Guy; Chen, Wei-Min; Franke, Andre; Gladman, Dafna D

    2015-01-01

    Human leukocyte antigen (HLA) genes confer substantial risk for autoimmune diseases on a log-additive scale. Here we speculated that differences in autoantigen-binding repertoires between a heterozygote's two expressed HLA variants might result in additional non-additive risk effects. We tested the non-additive disease contributions of classical HLA alleles in patients and matched controls for five common autoimmune diseases: rheumatoid arthritis (ncases = 5,337), type 1 diabetes (T1D; ncases...

  6. Ultaviolet-induced frameshift mutagenesis in Salmonella typhimurium: absence of an effect of mutation frequency decline

    Enhanced yields of UV-induced back mutants to prototrophy are observed when irradiated cells of the Salmonella typhimurium frameshift strain LT2 hisC3076(R46) are plated on defined medium containing broth (2.5%, v/v) rather than a trace (0.02 μg/ml) of the required nutrient (histidine). This broth effect is not abolished, and is in fact augmented, in an excision-deficient derivative of hisC3076(R46) carrying the uvr-302 mutation. Since similar broth effects on UV-induced base-pair substitution mutagenesis have usually been attributed to inhibition of mutation frequency decline (MFD), and since MFD is in turn thought to reflect the activity of an intact excision-repair system, we sought to determine whether or not UV-induced premutational lesions leading to the production of frameshifts are susceptible to MFD. Results with the doubly auxotrophic strain LT2 hisC3076 leuA150 (pKM101) showed that in a population of cells actually undergoing MFD (as judged by a rapid loss of UV-induced reversions of the base-pair substitution marker (leuA150)), no concomitant loss of UV-induced reversions of the frameshift hisC3076 marker could be detected. (orig.)

  7. Modulation of Additive and Interactive Effects in Lexical Decision by Trial History

    Masson, Michael E. J.; Kliegl, Reinhold

    2013-01-01

    Additive and interactive effects of word frequency, stimulus quality, and semantic priming have been used to test theoretical claims about the cognitive architecture of word-reading processes. Additive effects among these factors have been taken as evidence for discrete-stage models of word reading. We present evidence from linear mixed-model…

  8. Effect of small additions of vanadium and niobium on structure and mechanical properties of ductile iron

    Fraś E.; Górny M.; Kawalec M.

    2007-01-01

    Results of investigations of influence of small additions of vanadium (up to 0,15 % V) and niobium (up to 0,04% Nb) on structure of ductile iron is presented in this work. Effect of these additions on distribution of graphite nodule diameter, nodule count, fraction and carbide count have been determined. Investigations of effect of small additions of vanadium and niobium on mechanical properties taking into account tensile strength, yield strength and elongation have also been made.

  9. The Effect of Additional Funds for Low-Ability Pupils - A Nonparametric Bounds Analysis

    de Haan, Monique

    2012-01-01

    This paper investigates the effect of a policy measure that gives secondary schools additional resources for low-ability pupils. Schools are free in deciding how to spend the additional money. I use a nonparametric bounds analysis to estimate upper and lower bounds on the effect of additional funds on exam results of pupils. First I investigate what can be concluded without imposing assumptions; next I layer weak nonparametric assumptions to tighten the bounds. The tightest bounds show that t...

  10. Multi-mutational model for cancer based on age-time patterns of radiation effects: 2. Biological aspects

    Mendelsohn, M.L.; Pierce, P.A.

    1997-09-04

    Biological properties of relevance when modeling cancers induced in the atom bomb survivors include the wide distribution of the induced cancers across all organs, their biological indistinguishability from background cancers, their rates being proportional to background cancer rates, their rates steadily increasing over at least 50 years as the survivors age, and their radiation dose response being linear. We have successfully described this array of properties with a modified Armitage-Doll model using 5 to 6 somatic mutations, no intermediate growth, and the dose-related replacement of any one of these time-driven mutations by a radiation-induced mutation. Such a model is contrasted to prevailing models that use fewer mutations combined with intervening growth. While the rationale and effectiveness of our model is compelling for carcinogenesis in the atom bomb survivors, the lack of a promotional component may limit the generality of the model for other types of human carcinogenesis.

  11. Combined Effects of Thermal Neutrons and Diethyl Sulphate on Mutation Frequency and Spectrum in Rice

    Treatment of rice seeds of variety Ptb-10 with 0.076 molar solution of diethyl sulphate drastically reduced the germination of seeds to 21% and the survival of plants to 13%. When seeds irradiated with thermal neutron doses of 5 x 1011 nth/cm2, 1 x 1012 nth/cm2, 5 x 1012 nth/cm2 and 1 x 1013 nth/cm2 were treated with 0.076 M solution of diethyl sulphate, there was an increase of germination and survival with increase in thermal neutron dose. There was a synergistic effect on mutation frequency in combined treatments of 5 x 1011 nth/cm2 and 1 x 1012 nth/cm2 and diethyl sulphate. The mutation frequency, however, decreased with higher doses of neutron and chemical treatments corresponding to survival. Better germination with combined treatments was obtained only when the seeds were treated with the chemical within 24 to 36 h after irradiation. When irradiated seeds were stored for a week or more, no difference could be noted between chemical and combined treatments. Furthermore, low concentration (0.0456 M) and prolonged treatment (4 h) also failed to show appreciable increase in germination. The better germination and survival with some combined treatments can possibly be due to physiological stimulation often noticed with neutron irradiation or due to the acceleration of hydrolysis and loss of efficiency of the chemical. The decrease in mutation frequency with better survival suggests loss of efficiency of the chemical due to rapid hydrolysis. (author)

  12. Site-specific mutations of FtsZ - effects on GTPase and in vitro assembly

    Stricker Jesse

    2001-05-01

    Full Text Available Abstract Background FtsZ, the major cytoskeletal protein in bacterial cytokinesis, assembles in vitro into protofilaments, which can further associate into sheets, bundles or tubes. We have constructed 16 site-directed mutants of E. coli ftsZ, and tested them for GTP hydrolysis and assembly in vitro, and for their ability to complement the temperature sensitive ftsZ84 mutation in E. coli. Results The mutants were grouped into three classes. Benign mutants, which mapped mostly to the front and back surface of the protofilament, were able to complement ftsZ84 in vivo and showed normal assembly in vitro. GTP contact mutations had less than 10% of wild type GTPase activity. They could all assemble in vitro, and several of these mutants could complement ftsZ84. A third, and newly discovered, class of mutations mapped to the sides of the protofilaments. These lateral mutants had mostly normal GTPase and assembly in vitro, but none of them complemented ftsZ84. The non-complementing mutants showed greatly reduced expression from the pBS58 vector, suggesting possible dominant negative effects. Conclusions Several mutants with greatly reduced GTPase could still complement ftsZ84, suggesting that the high level of GTPase observed in vitro is not essential for in vivo function. All of the lateral mutants failed to complement ftsZ84, which suggests that these surfaces of the protofilaments are important for function in cell division. These lateral surfaces may mediate association of FtsZ protofilaments into pairs or small sheets, although their structure is apparently different from the sheets assembled in DEAE dextran or calcium.

  13. Effects on human transcriptome of mutated BRCA1 BRCT domain: A microarray study

    BRCA1 (breast cancer 1, early onset) missense mutations have been detected in familial breast and ovarian cancers, but the role of these variants in cancer predisposition is often difficult to ascertain. In this work, the molecular mechanisms affected in human cells by two BRCA1 missense variants, M1775R and A1789T, both located in the second BRCT (BRCA1 C Terminus) domain, have been investigated. Both these variants were isolated from familial breast cancer patients and the study of their effect on yeast cell transcriptome has previously provided interesting clues to their possible role in the pathogenesis of breast cancer. We compared by Human Whole Genome Microarrays the expression profiles of HeLa cells transfected with one or the other variant and HeLa cells transfected with BRCA1 wild-type. Microarray data analysis was performed by three comparisons: M1775R versus wild-type (M1775RvsWT-contrast), A1789T versus wild-type (A1789TvsWT-contrast) and the mutated BRCT domain versus wild-type (MutvsWT-contrast), considering the two variants as a single mutation of BRCT domain. 201 differentially expressed genes were found in M1775RvsWT-contrast, 313 in A1789TvsWT-contrast and 173 in MutvsWT-contrast. Most of these genes mapped in pathways deregulated in cancer, such as cell cycle progression and DNA damage response and repair. Our results represent the first molecular evidence of the pathogenetic role of M1775R, already proposed by functional studies, and give support to a similar role for A1789T that we first hypothesized based on the yeast cell experiments. This is in line with the very recently suggested role of BRCT domain as the main effector of BRCA1 tumor suppressor activity

  14. Effect of Particle Addition on Degradation Rate of Methylene Blue in an Ultrasonic Field

    Honma, Chiemi; Kobayashi, Daisuke; Matsumoto, Hideyuki; Takahashi, Tomoki; Kuroda, Chiaki; Otake, Katsuto; Shono, Atsushi

    2013-07-01

    Ultrasound has been found to be an attractive advanced technology for the degradation of hazardous organic compounds in water. In addition, the sonochemical reaction is enhanced by particle addition. However, the enhancement mechanism of particle addition has not been investigated well, because ultrasound enhances not only chemical reactions but also mass transfer. In this study, the ultrasonic degradation of methylene blue was carried out, and the effects of the ultrasonic irradiation condition on the degradation rate were investigated. The effect of ultrasonic frequency on the improvement of degradation by particle addition was also investigated. The order of degradation rate with frequency was the same as the tendency of sonochemical efficiency value obtained using KI oxidation dosimetry method (SEKI). The degradation process of methylene blue was intensified by particle addition, and the degradation rate increased with increasing amount of particle addition. The enhancement of degradation rate by particle addition was influenced by both ultrasonic frequency and type or diameter of particles.

  15. The combined effect of two mutations that alter serially homologous color pattern elements on the fore and hindwings of a butterfly

    Vedder Lindsey

    2007-05-01

    differentiation of the signaling centers of a subset of the serial homologous eyespots present on both the fore and the hindwing in a dose-dependent fashion. The effect of Missing on the forewing, however, is only observed when the mutation Spotty introduces additional eyespots on this wing. Spotty, on the other hand, controls the differentiation of eyespot centers only on the forewing. Spotty, unlike Missing, may be under Ubx gene regulation, since it affects a subset of eyespots on only one of the serially homologous wings.

  16. Mutation effects of C2+ ion irradiation on the greasy Nitzschia sp

    Highlights: • The optimal conditions of C2+ ion irradiation on Nitzschia sp. were discussed. • Get the “saddle type” survival curve. • One mutant whose lipid content improved significantly was selected. • The C2+ ion irradiation didn’t change the algae's morphology and growth rate. - Abstract: Screening and nurturing algae with high productivity, high lipid content and strong stress resistance are very important in algae industry. In order to increase the lipid content, the Nitzschia sp. was irradiated with a 3 MeV C2+ beam. The sample pretreatment method was optimized to obtain the best mutagenic condition and the survival ratio curve. The positive mutants with a significant improvement in lipid content were screened and their C2+ mutagenic effects were analyzed by comparing the greasiness and growth characteristics with the wild type algae. Results showed that when the Nitzschia sp. was cultivated in nutritious medium containing 10% glycerol solution, and dried on the filter for 5 min after centrifugation, the realization of the microalgae heavy ion mutagenesis could be done. The survival ratio curve caused by C2+ irradiation was proved to be “saddle-shaped”. A positive mutant was screened among 20 survivals after irradiation, the average lipid content of the mutation increased by 9.8% than the wild type after 4 generations. But the growth rate of the screened mutation didn’t change after the heavy ion implantation compared to the wild type algae

  17. Site-directed mutation of a laccase from Thermus thermophilus: Effect on the activity profile

    Liu Xin

    2012-01-01

    Full Text Available A site-directed mutant R453T of a laccase from Thermus thermophilus HB27 (Tth-laccase was constructed in order to investigate the effect on laccase catalytic properties. The mutated gene was cloned and overexpressed in Escherichia coli. Nickel-affinity purification was achieved and followed by copper ion incorporation. The mature mutated enzyme was quantitatively equal to the wild type. A photometric assay based on the oxidation of the substrate 2,2-azino-bis-(3- ethylbenzthiazoline-6-sulfonate (ABTS was employed in comparison with the wild-type Tth-laccase on catalytic properties. The R453T mutant exhibited improvement in substrate affinity and specific activity at room temperature, whereas those parameters were not significantly influenced when the temperature increased up to 65°C or higher. The mutant had better catalytic activity than that of the wild type at acidic pH. Investigated by circular dichroism spectroscopy, the mutant Tth-laccase displayed similar profiles at low and high temperatures.

  18. Study on mutation induced effect of gamma ray and DES on black bean phaseolus vulgaris

    The study on mutation induced effect of gamma ray and DES on black bean Phaseolus vulgaris was carried out at Radiobiology Department, Nuclear Research Institute of Dalat. Dry seeds of variety No.1847 - Bonita - Cuba in set of 13 black bean varieties were irradiated with gamma ray from 60Co source at dose range from 150 Gy to 350 Gy and treated with DES at concentration from 0.1% to 0.3% in 2 hours for experiments in laboratory. The doses of 200, 250, 300 Gy and concentration of 0.2% DES in 2 hours were selected to treat dry seeds for experiments on the field. In populations of M1 generation, the height, number of branches and fruits per plant, number of seeds per fruit were decreased with increasing of irradiation doses. In populations of M2 generation, individual variants in leaf shape, chlorophyll, short stem, dwarf, early maturity, flowering in very short time were obtained and selected in all treatment cases. Mutation frequency at dose of 300 Gy was higher than that in other treatment cases, but ratio of sterility is also largest. The mutant lines of early maturity and short stem with flowering in very short time are promised materials for further studies. (author)

  19. Effect of mutations in the uthetarD cistron of Escherichia coli on repair resynthesis

    Kuemmerle, N.B.; Ley, R.D.; Masker, W.E. (Oak Ridge National Lab., TN (USA). Biology Div.)

    1982-01-01

    The resynthesis step of the excision repair pathway has been examined in Escherichia coli K12 strains isogenic except for mutations in the uvrD cistron. Strains mutant at the uvrD3, uvrD101, uvrE156, and recLl52 loci exhibited slight but distinct differences in their response to ultraviolet radiation. The repair capacity of the uvrD101 mutant was given special attention. Repair resynthesis in this mutant was saturated at fluences greater than about 20 J/m/sup 2/. Isopycnic analysis of repaired deoxyribonucleic acid from this strain revealed a two-fold increase over its wild-type counterpart in the amount of repair replication performed after a dose of 15 J/m/sup 2/. Sedimentation velocity analysis of DNA after selective photolysis of bromouracil-containing repaired regions showed that the uvrD101 mutation exerted its primary effect on the long-patch component of excision repair. The uvrD101 mutant performed long-patch repair at a larger number of sites than the number repaired by this mode in the wild-type strain; these patches were more extensive in length than the long-patch component in wild-type.

  20. The effect of mutations in the uthetarD cistron of Escherichia coli on repair resynthesis

    The resynthesis step of the excision repair pathway has been examined in Escherichia coli K12 strains isogenic except for mutations in the uvrD cistron. Strains mutant at the uvrD3, uvrD101, uvrE156, and recLl52 loci exhibited slight but distinct differences in their response to ultraviolet radiation. The repair capacity of the uvrD101 mutant was given special attention. Repair resynthesis in this mutant was saturated at fluences greater than about 20 J/m2. Isopycnic analysis of repaired deoxyribonucleic acid from this strain revealed a two-fold increase over its wild-type counterpart in the amount of repair replication performed after a dose of 15 J/m2. Sedimentation velocity analysis of DNA after selective photolysis of bromouracil-containing repaired regions showed that the uvrD101 mutation exerted its primary effect on the long-patch component of excision repair. The uvrD101 mutant performed long-patch repair at a larger number of sites than the number repaired by this mode in the wild-type strain; these patches were more extensive in length than the long-patch component in wild-type. (orig.)

  1. The state of the art on zinc addition effect in the nuclear reactor coolant system

    Zinc addition to the primary coolant appears promising with regard to reducing radiation dose rate, and is being used in several plants. Zinc acts to inhibit the corrosion of stainless steel by forming a thin protective film. This oxide film, with no associated increase in cobalt concentration within the film, thereby lowers the dose rate. This report on the state of art presents an overview of the zinc addition to the reactor coolant to reduce the primary system dose rate. This report discusses the effect of zinc addition for BWRs and PWRs, the thermodynamic of zinc chemistry, and the effect of zinc addition on material corrosion. (author)

  2. The state of the art on zinc addition effect in the nuclear reactor coolant system

    Kim, U. C.; Sung, K. W.; Kim, K. R.; Paek, S.; Maeng, W. Y

    1999-12-01

    Zinc addition to the primary coolant appears promising with regard to reducing radiation dose rate, and is being used in several plants. Zinc acts to inhibit the corrosion of stainless steel by forming a thin protective film. This oxide film, with no associated increase in cobalt concentration within the film, thereby lowers the dose rate. This report on the state of art presents an overview of the zinc addition to the reactor coolant to reduce the primary system dose rate. This report discusses the effect of zinc addition for BWRs and PWRs, the thermodynamic of zinc chemistry, and the effect of zinc addition on material corrosion. (author)

  3. The Ups and Downs of Mutation Frequencies during Aging Can Account for the Apert Syndrome Paternal Age Effect

    Song-Ro Yoon; Jian Qin; Rivka L Glaser; Ethylin Wang Jabs; Wexler, Nancy S; Rebecca Sokol; Norman Arnheim; Peter Calabrese

    2009-01-01

    Author Summary Epidemiological studies show that the incidence of some genetic diseases increases with the age of the father. This “paternal age effect” is traditionally explained by the fact that, as men age, the male germ-line cells continue to divide, and each division presents an additional chance for mutation. Apert syndrome is an example of such a disease; virtually all cases are caused by spontaneous base substitution mutations of paternal origin at either one of just two sites. In thi...

  4. Biphenyl compounds are hydroxyl radical scavengers: their effective inhibition for UV-induced mutation in Salmonella typhimurium TA102.

    Fujita, S; Taira, J

    1994-09-01

    In our previous study, we found several hydroxylated biphenyl compounds have a great scavenging effect for hydroxyl radicals (.OH). In this study, to elucidate the relationship between generation of the .OH and photo-mutagenesis, six biphenyl compounds such as dehydrodieugenol, dehydrodivanillyl alcohol, dehydrodidihydroeugenol, dehydrodicreosol, magnolol and honokiol, respectively, were examined for their ability to inhibit UV-induced mutation in Salmonella typhimurium TA102. The relative mutagenic activities (RMA, %) indicated the mutation frequency of treated cells divided by the mutation frequency of control cells times 100%. The RMA (%) are as follows: 28 +/- 1, 31 +/- 1, 33 +/- 1, 41 +/- 2, 62 +/- 1, and 62 +/- 4 at concentrations of 5 micrograms per plate for dehydrodieugenol, dehydrodivanillyl alcohol, dehydrodidihydroeugenol, dehydrodicreosol, magnolol, and honokiol, respectively. These values indicate that low concentrations of these biphenyl compounds effectively suppress UV-induced mutagenesis. Also, these compounds acted as effective antimutagens in a dose-dependent manner (0.00005-5 micrograms per plate). These compounds are effective .OH scavengers. Consequently, the results obtained above suggest that these compounds could inhibit against UV-induced mutations by scavenging of .OH generated by UV irradiation. The results also suggest that .OH are associated with UV-induced mutation in Salmonella typhimurium TA102. PMID:7982632

  5. Non-additive genetic effects for fertility traits in Canadian Holstein cattle (Open Access publication

    Miglior Filippo

    2007-02-01

    Full Text Available Abstract The effects of additive, dominance, additive by dominance, additive by additive and dominance by dominance genetic effects on age at first service, non-return rates and interval from calving to first service were estimated. Practical considerations of computing additive and dominance relationships using the genomic relationship matrix are discussed. The final strategy utilized several groups of 1000 animals (heifers or cows in which all animals had a non-zero dominance relationship with at least one other animal in the group. Direct inversion of relationship matrices was possible within the 1000 animal subsets. Estimates of variances were obtained using Bayesian methodology via Gibbs sampling. Estimated non-additive genetic variances were generally as large as or larger than the additive genetic variance in most cases, except for non-return rates and interval from calving to first service for cows. Non-additive genetic effects appear to be of sizeable magnitude for fertility traits and should be included in models intended for estimating additive genetic merit. However, computing additive and dominance relationships for all possible pairs of individuals is very time consuming in populations of more than 200 000 animals.

  6. Random point mutations with major effects on protein-coding genes are the driving force behind premature aging in mtDNA mutator mice.

    Edgar, D.; Shabalina, I.; Camara, Y.; Wredenberg, A.; Calvaruso, M.A.; Nijtmans, L.G.J.; Nedergaard, J.; Cannon, B.; Larsson, N.G.; Trifunovic, A.

    2009-01-01

    The mtDNA mutator mice have high levels of point mutations and linear deletions of mtDNA causing a progressive respiratory chain dysfunction and a premature aging phenotype. We have now performed molecular analyses to determine the mechanism whereby these mtDNA mutations impair respiratory chain fun

  7. The Inhibitory Effects of Aqueous Extract from Guava Twigs, Psidium guajava L., on Mutation and Oxidative Damage

    Zhi-Chyang Kang

    2013-01-01

    Full Text Available This study examines the inhibitory effects of the aqueous extract from guava twigs (GTE, Psidium guajava L., on mutation and oxidative damage. The results show that GTE inhibits the mutagenicity of 4-nitroquinoline-N-oxide (4-NQO, a direct mutagen, and 2-aminoanthracene (2-AA, an indirect mutagen, toward Salmonella typhimurium TA 98 and TA 100. In addition, GTE shows radical scavenging, reducing activities, tyrosinase inhibition, and liposome protection effects. Meanwhile, GTE in the range of 0.1–0.4 mg/mL protects liver cells from tert-butyl-hydroperoxide-(t-BHP- induced cytotoxicity. Furthermore, the cytotoxicity inhibition of GTE in the t-BHP-treated cells was demonstrated in a dose-dependent manner. High-performance liquid chromatography analysis suggests that the major phenolic constituents in GTE are gallic acid, ferulic acid, and myricetin. These active phenolic components may contribute to the biological protective effects of GTE in different models. The data suggest that GTE exhibiting biological activities can be applied to antimutation, antityrosinase, and antioxidative damage.

  8. Additivity of Feature-Based and Symmetry-Based Grouping Effects in Multiple Object Tracking.

    Wang, Chundi; Zhang, Xuemin; Li, Yongna; Lyu, Chuang

    2016-01-01

    Multiple object tracking (MOT) is an attentional process wherein people track several moving targets among several distractors. Symmetry, an important indicator of regularity, is a general spatial pattern observed in natural and artificial scenes. According to the "laws of perceptual organization" proposed by Gestalt psychologists, regularity is a principle of perceptual grouping, such as similarity and closure. A great deal of research reported that feature-based similarity grouping (e.g., grouping based on color, size, or shape) among targets in MOT tasks can improve tracking performance. However, no additive feature-based grouping effects have been reported where the tracking objects had two or more features. "Additive effect" refers to a greater grouping effect produced by grouping based on multiple cues instead of one cue. Can spatial symmetry produce a similar grouping effect similar to that of feature similarity in MOT tasks? Are the grouping effects based on symmetry and feature similarity additive? This study includes four experiments to address these questions. The results of Experiments 1 and 2 demonstrated the automatic symmetry-based grouping effects. More importantly, an additive grouping effect of symmetry and feature similarity was observed in Experiments 3 and 4. Our findings indicate that symmetry can produce an enhanced grouping effect in MOT and facilitate the grouping effect based on color or shape similarity. The "where" and "what" pathways might have played an important role in the additive grouping effect. PMID:27199875

  9. Effects of the jimpy mutation on mouse retinal structure and function.

    Hovhannisyan, Anahit; Benkner, Boris; Biesemeier, Antje; Schraermeyer, Ulrich; Kukley, Maria; Münch, Thomas A

    2015-12-15

    The Jimpy mutant mouse has a point mutation in the proteolipid protein gene (plp1). The resulting misfolding of the protein leads to oligodendrocyte death, myelin destruction, and failure to produce adequately myelinated axons in the central nervous system (CNS). It is not known how the absence of normal myelination during development influences neural function. We characterized the Jimpy mouse retina to find out whether lack of myelination in the optic nerve during development has an effect on normal functioning and morphology of the retina. Optokinetic reflex measurements showed that Jimpy mice had, in general, a functional visual system. Both PLP1 antibody staining and reverse transcriptase-polymerase chain reaction for plp1 mRNA showed that plp1 is not expressed in the wild-type retina. However, in the optic nerve, plp1 is normally expressed, and consequently, in Jimpy mutant mice, myelination of axons in the optic nerve was mostly absent. Nevertheless, neither axon count nor axon ultrastructure in the optic nerve was affected. Physiological recordings of ganglion cell activity using microelectrode arrays revealed a decrease of stimulus-evoked activity at mesopic light levels. Morphological analysis of the retina did not show any significant differences in the gross morphology, such as thickness of retinal layers or cell number in the inner and outer nuclear layer. The cell bodies in the inner nuclear layer, however, were larger in the peripheral retina of Jimpy mutant mice. Antibody labeling against cell type-specific markers showed that the number of rod bipolar and horizontal cells was increased in Jimpy mice. In conclusion, whereas the Jimpy mutation has dramatic effects on the myelination of retinal ganglion cell axons, it has moderate effects on retinal morphology and function. PMID:26011242

  10. Non–lineage/stage-restricted effects of a gain-of-function mutation in tyrosine phosphatase Ptpn11 (Shp2) on malignant transformation of hematopoietic cells

    Xu, Dan; Liu, Xia; Yu, Wen-Mei; Meyerson, Howard J.; Guo, Caiying; Gerson, Stanton L.; Qu, Cheng-Kui

    2011-01-01

    Activating mutations in protein tyrosine phosphatase 11 (Ptpn11) have been identified in childhood acute leukemias, in addition to juvenile myelomonocytic leukemia (JMML), which is a myeloproliferative disorder (MPD). It is not clear whether activating mutations of this phosphatase play a causal role in the pathogenesis of acute leukemias. If so, the cell origin of leukemia-initiating stem cells (LSCs) remains to be determined. Ptpn11E76K mutation is the most common and most active Ptpn11 mut...

  11. Effects of Food Additives on Susceptibility of Gram Negative Bacteria Derived from Dry-Fermented Sausage

    DORJ, Serjmyadag; SHIMADA, Kenichiro; SEKIKAWA, Mitsuo; 島田, 謙一郎; 関川, 三男

    2009-01-01

    This study examined the effects of food additives on gram-negative bacteria. The food additives used included synthetic antioxidants (butylated hydroxyanisole, BHA, and butylated hydroxytoluene, BHT), a curing agent and lactic acid with or without a cell-free supernatant (CFS) containing antimicrobial compounds of Lactobacillus sakei D-1001. The gram-negative bacteria were selected from dry-fermented sausages and cultured with different food additives for 18 h in nutrient broth, and then anot...

  12. Effect of Additives on Wood Pellet Physical and Thermal Characteristics: A Review

    Dmitry Tarasov; Chander Shahi; Mathew Leitch

    2013-01-01

    Additives play a major role in wood pellet characteristics and are a subject of major interest as they act as binding agents for the biomass raw material. Past research has reported the use of lignosulphonate, dolomite, starches, potato flour and peel, and some motor and vegetable oils as additives for wood pellet production. This paper reviews the available research on the effect of different additives on wood pellets' physical and thermal characteristics. It was found that lignosulphonate a...

  13. The Effects of Different Silage Additives on the Quality of Sugar Beet Pulp Silage

    ŞAHİN, Kâzım; ÇERÇİ, İ. Halil; GÜLER, Talat

    1999-01-01

    In this study, the effect of different silage additive added during ensiling period was investigated on the silages quality and determination of storage characters of sugar beet pulp. Treatment groups consisted of silage additives. These groups were K group no additives, F group with %5 formic acid, P group with %8 whole crop barley after wilting silage, M group with %8 corn silage and S group with whole crop barley added straw with treated HCI silage. The changes in nutrients contents, fe...

  14. Mutagenic effects of gamma rays and EMS on frequency and spectrum of chlorophyll mutations in urdbean (Vigna mungo (L.) Hepper)

    Chlorophyll mutations act as a significant index in the judgment of induced genetic variations in mutagen treated populations. Different types of chlorophyll mutation have been observed in various crop plants. In the current study, the effect of different concentrations (40 kR, 50 kR and 60 kR) of gamma rays, Ethyl Methane Sulphonate (50 mM, 60 mM and 70 mM) in single and combination dose/concentration on the frequency and spectrum of chlorophyll mutation and the effect of VBN 4 urdbean variety to such irradiation dose was observed. Results showed induction of broad spectrum of chlorophyll mutations which included albina, xantha, chlorina and viridis. Among these chlorina type was predominant in all the mutagenic treatments. The albina type of chlorophyll mutants occurred very rarely and was found only at 60 mM of EMS treatment and at 40 kR + 50 mM, 60 kR + 70 mM of combination treatments. Based on the chlorophyll mutation frequency, gamma rays were most effective followed by EMS and combination of treatments. (author)

  15. Synergistic effect of additives including multifunctional acrylates in wood plastic composites

    Wood Plastic Composite (WPC) was prepared with simul (soft wood, density = 0.4g/cc) and butylmethacrylate (BMA) monomer using 10% methanol as the swelling agent. Effect of additives including multifunctional acrylates such as tripropylene glycol diacrylate (TPGDA), trimethylol propane triacrylate (TMPTA), oligomer acrylates like the urethane (UA), epoxy (EA) and polyester (PEA) acrylates and N-vinyl pyrrolidone (NVP) was investigated using 1 to 3 Mrad dose at 0.8 Mrad/h. Synergistic increases in polymer loading yields was achieved in presence of the additives, particularly with the trifunctional acrylate (TMPTA). In addition, acid as well as urea were also used as co-additives and synergistic enhancement in yields of polymer loading were obtained. The synergistic polymer loading by acid addition causes substantial decrease in tensile strength of the composite; but other additives and co-additives increase both the polymer loading and the tensile strength in these systems. (author)

  16. Cardiac effects of the c.1583 C→G LMNA mutation in two families with Emery-Dreifuss muscular dystrophy.

    Zhang, Li; Shen, Hongrui; Zhao, Zhe; Bing, Qi; Hu, Jing

    2015-10-01

    The present study aimed to examine and analyze cardiac involvement in two Emery‑Dreifuss muscular dystrophy (EDMD) pedigrees caused by the c.1583 C→G mutation of the lamin A/C gene (LMNA). The clinical and genetic characteristics of members of two families with EDMD were evaluated by performing neurological examinations, skeletal muscle biopsies, cardiac evaluations, including electrocardiography, 24 h Holter, ultrasound cardiography and 99TcM‑MIBI‑gated myocardiac perfusion imaging, and genomic DNA sequencing. Family history investigations revealed an autosomal dominant transmission pattern of the disease in Family 1 and a sporadic case in Family 2. The three affected patients exhibited typical clinical features of EDMD, including joint contractures, muscle weakness and cardiac involvement. Muscle histopathological investigation revealed dystrophic features. In addition, each affected individual exhibited either cardiac arrhythmia, which was evident as sinus tachycardia, atrial flutter or complete atrioventricular inhibition. Cardiac imaging revealed dilated cardiomyopathy in two of the individuals, one of whom was presented with heart failure. The second patient presented with no significant abnormalities in cardiac structure or function. The three affected individuals exhibited a heterozygous missense mutation in the LMNA gene (c.1583 C→G), which caused a T528R amino acid change in the LMNA protein. In conclusion, the present study identified three patients with EDMD, exhibiting the same dominant LMNA mutation and presenting with a spectrum of severe cardiac abnormalities, including cardiac conduction system defects, cardiomyopathy and heart failure. As LMNA mutations have been associated with at least six clinical disorders, including EDMD, the results of the present study provide additional mutational and functional data, which may assist in further establishing LMNA mutational variation and disease pathogenesis. PMID:26165385

  17. Effects of biological pit additives on microbial ecology of stored pig manure

    The effects of biological pit additives on microbial ecology in stored pig manure were investigated using a dynamic manure storage system, which allowed for continual addition of swine feces and urine. After 13 weeks of manure collection and storage, four treatments were added to tanks (900 L capaci...

  18. Effect of cold atmospheric pressure He-plasma jet on DNA change and mutation

    Yaopromsiri, C.; Yu, L. D.; Sarapirom, S.; Thopan, P.; Boonyawan, D.

    2015-12-01

    Cold atmospheric pressure plasma jet (CAPPJ) effect on DNA change was studied for assessment of its safety. The experiment utilized a home-developed CAPPJ using 100% helium to directly treat naked DNA plasmid pGFP (plasmid green fluorescent protein). A traversal electric field was applied to separate the plasma components and both dry and wet sample conditions were adopted to investigate various factor roles in changing DNA. Plasma species were measured by using optical emission spectroscopy. DNA topological form change was analyzed by gel electrophoresis. The plasma jet treated DNA was transferred into bacterial Escherichia coli cells for observing mutation. The results show that the He-CAPPJ could break DNA strands due to actions from charge, radicals and neutrals and potentially cause genetic modification of living cells.

  19. Trends in lignin modification: a comprehensive analysis of the effects of genetic manipulations/mutations on lignification and vascular integrity

    Anterola, Aldwin M.; Lewis, Norman G.

    2002-01-01

    activities. Such enzymes thus fulfill subsidiary processing roles, with all (except CCOMT) apparently being bifunctional for both H and G substrates. Their severe downregulation does, however, predictably result in impaired monolignol biosynthesis, reduced lignin deposition/vascular integrity, (upstream) metabolite build-up and/or shunt pathway metabolism. There was no evidence for an alternative acid/ester O-methyltransferase (AEOMT) being involved in lignin biosynthesis.The G/S lignin pathway networks are operative in specific cell types in angiosperms and employ two additional biosynthetic steps to afford the corresponding S components, i.e. through introduction of an hydroxyl group at C-5 and its subsequent O-methylation. [These enzymes were originally classified as ferulate-5-hydroxylase (F5H) and caffeate O-methyltransferase (COMT), respectively.] As before, neither step has apparently any role in carbon allocation to the pathway; hence their individual downregulation/manipulation, respectively, gives either a G enriched lignin or formation of the well-known S-deficient bm3 "lignin" mutant, with cell walls of impaired vascular integrity. In the latter case, COMT downregulation/mutation apparently results in utilization of the isoelectronic 5-hydroxyconiferyl alcohol species albeit in an unsuccessful attempt to form G-S lignin proper. However, there is apparently no effect on overall G content, thereby indicating that deposition of both G and S moieties in the G/S lignin forming cells are kept spatially, and presumably temporally, fully separate. Downregulation/mutation of further downstream steps in the G/S network [i.e. utilizing 4CL, CCR and CAD isoforms] gives predictable effects in terms of their subsidiary processing roles: while severe downregulation of 4CL gave phenotypes with impaired vascular integrity due to reduced monolignol supply, there was no evidence in support of increased growth and/or enhanced cellulose biosynthesis. CCR and CAD downregulation/mutations

  20. Polyelectrolyte addition effect on the properties of setting hydraulic cements based on calcium phosphate

    In the present work the effects of the addition of some poly electrolytes (sodium alginate and poly acrylic acid) on the solubility, crystalline phases, pH and mechanical strength under compression of three calcium phosphate cements were studied. (author)

  1. 75 FR 66752 - ILP Effectiveness Evaluation 2010; Additional Notice of Multi-Stakeholder Technical Conference on...

    2010-10-29

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF ENERGY Federal Energy Regulatory Commission ILP Effectiveness Evaluation 2010; Additional Notice of Multi- Stakeholder..., ``Notice of Interviews, Teleconferences, Regional Workshops And Multi-Stakeholder Technical Conference...

  2. Combined-modality radioimmunotherapy: synergistic effect of paclitaxel and additive effect of bevacizumab

    Introduction: This study was undertaken to investigate the effect of paclitaxel and bevacizumab on the therapeutic efficacy of 90Y-labeled B3 monoclonal antibody, directed against Ley antigen, for the treatment of Ley-positive A431 tumors implanted subcutaneously in the right hind flank of nude mice. Methods: When the tumor size reached ∼200 mm3, the mice received a single dose of intravenous (iv) 90Y-labeled B3 (60 μCi/150 μg or 100 μCi/150 μg B3), intraperitoneal paclitaxel (40 mg/kg) or iv bevacizumab (5 mg/kg) for monotherapy. To investigate the effect of combined therapies on survival, the mice were treated with two or three agents in the following combinations: 90Y-B3 on day 0 and paclitaxel on day 1; bevacizumab on −1 day and 90Y-B3 on day 0; bevacizumab on −1 day and paclitaxel on day 1; bevacizumab, 90Y-B3 and paclitaxel each at 1-day intervals. The mice with no treatment were used as a control. The tumor volume at 1000 mm3 was used as a surrogate end point of survival. Results: Compared to control animals, paclitaxel delayed tumor growth with a significantly longer median survival time (P90Y-B3 increased the median survival time in a dose-dependent manner (P90Y-B3 showed a statistically insignificant increase in the median survival time compared to 90Y-B3 alone (P=.25). The tumor sizes of all animals in these groups reached the surrogate end point of survival by day 35. In contrast, the combined therapy involving 90Y-B3 with paclitaxel showed a striking synergistic effect in shrinking tumors and prolonging the survival time (P90Y-B3 and 100 μCi 90Y-B3, respectively. The addition of bevacizumab treatment 1 day before the combined therapy of 60 μCi 90Y-B3 with paclitaxel did not produce a statistically significant increase in survival when compared to the 90Y-B3 with paclitaxel (P>.10). Fluorescence microscopy analysis indicated that paclitaxel increased, whereas bevacizumab decreased, the accumulation and penetration of Alexa Fluor 647-B3 into

  3. Effects of 16S rRNA gene mutations on tetracycline resistance in Helicobacter pylori

    Gerrits, Monique; Berning, M.; Vliet, Arnoud; Kuipers, Ernst; Kusters, Johannes

    2003-01-01

    textabstractThe triple-base-pair 16S rDNA mutation AGA(926-928)-->TTC mediates high-level tetracycline resistance in Helicobacter pylori. In contrast, single- and double-base-pair mutations mediated only low-level tetracycline resistance and decreased growth rates in the presence of tetracycline, explaining the preference for the TTC mutation in tetracycline-resistant H. pylori isolates.

  4. Categorical and continuous - disentangling the neural correlates of the carry effect in multi-digit addition

    Dressel Katharina; Willmes Klaus; Klein Elise; Domahs Frank; Wood Guilherme; Nuerk Hans-Christoph; Moeller Korbinian

    2010-01-01

    Abstract Background Recently it was suggested that the carry effect observed in addition involves both categorical and continuous processing characteristics. Methods In the present study, we aimed at identifying the specific neural correlates associated with processing either categorical or continuous aspects of the carry effect in an fMRI study on multi-digit addition. Results In line with our expectations, we observed two distinct parts of the fronto-parietal network subserving numerical co...

  5. Effects of T592 phosphomimetic mutations on tetramer stability and dNTPase activity of SAMHD1 can not explain the retroviral restriction defect.

    Bhattacharya, Akash; Wang, Zhonghua; White, Tommy; Buffone, Cindy; Nguyen, Laura A; Shepard, Caitlin N; Kim, Baek; Demeler, Borries; Diaz-Griffero, Felipe; Ivanov, Dmitri N

    2016-01-01

    SAMHD1, a dNTP triphosphohydrolase, contributes to interferon signaling and restriction of retroviral replication. SAMHD1-mediated retroviral restriction is thought to result from the depletion of cellular dNTP pools, but it remains controversial whether the dNTPase activity of SAMHD1 is sufficient for restriction. The restriction ability of SAMHD1 is regulated in cells by phosphorylation on T592. Phosphomimetic mutations of T592 are not restriction competent, but appear intact in their ability to deplete cellular dNTPs. Here we use analytical ultracentrifugation, fluorescence polarization and NMR-based enzymatic assays to investigate the impact of phosphomimetic mutations on SAMHD1 tetramerization and dNTPase activity in vitro. We find that phosphomimetic mutations affect kinetics of tetramer assembly and disassembly, but their effects on tetramerization equilibrium and dNTPase activity are insignificant. In contrast, the Y146S/Y154S dimerization-defective mutant displays a severe dNTPase defect in vitro, but is indistinguishable from WT in its ability to deplete cellular dNTP pools and to restrict HIV replication. Our data suggest that the effect of T592 phosphorylation on SAMHD1 tetramerization is not likely to explain the retroviral restriction defect, and we hypothesize that enzymatic activity of SAMHD1 is subject to additional cellular regulatory mechanisms that have not yet been recapitulated in vitro. PMID:27511536

  6. Effects of BRCA1 and BRCA2 mutations on female fertility

    Smith, Ken R.; Hanson, Heidi A.; Mineau, Geraldine P; Buys, Saundra S.

    2011-01-01

    Women with BRCA1/2 mutations have a significantly higher lifetime risk of developing breast or ovarian cancer. We suggest that female mutation carriers may have improved fitness owing to enhanced fertility relative to non-carriers. Here we show that women who are carriers of BRCA1/2 mutations living in natural fertility conditions have excess fertility as well as excess post-reproductive mortality in relation to controls. Individuals who tested positive for BRCA1/2 mutations who linked into m...

  7. A Recessive Mutation in the APP Gene with Dominant-Negative Effect on Amyloidogenesis

    Di Fede, G; Catania, M; Morbin, M; Rossi, G; S. Suardi; Mazzoleni, G; Merlin, M.; A.R. Giovagnoli; Prioni, S.; A. Erbetta; C. Falcone; Gobbi, M.; L. Colombo; A. Bastone; M. Beeg

    2009-01-01

    β-Amyloid precursor protein (APP) mutations cause familial Alzheimer’s disease with nearly complete penetrance. We found an APP mutation [alanine-673→valine-673 (A673V)] that causes disease only in the homozygous state, whereas heterozygous carriers were unaffected, consistent with a recessive Mendelian trait of inheritance. The A673V mutation affected APP processing, resulting in enhanced β-amyloid (Aβ) production and formation of amyloid fibrils in vitro. Co-incubation of mutated and wild-t...

  8. Effects of Roundup formulations, nutrient addition, and Western mosquitofish (Gambusia affinis) on aquatic communities.

    Geyer, Rebecca L; Smith, Geoffrey R; Rettig, Jessica E

    2016-06-01

    Aquatic communities can be affected by herbicides, nutrient addition, and non-native fish species. We conducted a mesocosm experiment to examine the direct and interactive effects of three stressors: (1) Roundup formulations (Roundup Weed and Grass Killer(®) and Roundup Poison Ivy and Tough Brush Killer Plus(®)), (2) nutrient addition, and (3) the presence of the non-native Western mosquitofish (Gambusia affinis), on experimental pond communities. Roundup formulations had the most widespread effects on the zooplankton community, but effects varied between formulations and among taxa. The only significant effect of nutrient addition was a lowering of Daphnia abundance in the nutrient addition treatments. The abundances of Daphnia, mid-sized cladocerans, and total zooplankton were lowered by mosquitofish, but no other taxa showed significant mosquitofish effects. We found several two-way and three-way interactions among the stressors, but these varied among zooplankton taxa. Chlorophyll a levels were higher with nutrient addition but were not significantly affected by Roundup formulation or mosquitofish. Our results suggest toxicity of Roundup formulations varies among taxa, and Roundup formulations differ in their toxicity to zooplankton, but with no cascading effects on primary producers. In addition, interactions among stressors affected the zooplankton community. PMID:26944427

  9. Effect of Nano Oil Additive Proportions on Friction and Wear Performance of Automotive Materials

    A. Vadiraj

    2012-03-01

    Full Text Available The effect of nano boric acid and nano copper based engine and transmission oil additives in different volume ratios (1:10, 2:10, and 3:10 on friction and wear performance of cast iron and case carburized gear steel has been investigated. The results show that coefficient of friction increases with increase in volume ratio of engine oil additives and decreases with increasing in volume ratio of transmission oil additives. Cast iron substrate shows higher wear damage than case carburized gear steel. Nano copper additive with crystalline atomic structure shows more severe three body wear compared to boric acid with layered lattice structure.

  10. The Effects of Non—Metal Additives on Hydration Reisitance of MgO—C Bricks

    OUYAGNG; WANGRuikun; 等

    2000-01-01

    The general method of solving the problem of hydration of MgO-C brick is by adding with metal Si,Mg or compround metal additives,but metal additives have bad effect on the MgO-C brick,The test tried adding non-metal additives to matrix material.The results showed that a suitable amount of this kind of additives not only inhibits hydration of MgO-C brick and does not affect corrosion resistance and avoids thermal expansion,but also can improve oxidation resistance.

  11. Dlx5 Homeodomain:DNA Complex: Structure, Binding and Effect of Mutations Related to Split Hand and Foot Malformation Syndrome.

    Proudfoot, Andrew; Axelrod, Herbert L; Geralt, Michael; Fletterick, Robert J; Yumoto, Fumiaki; Deacon, Ashley M; Elsliger, Marc-André; Wilson, Ian A; Wüthrich, Kurt; Serrano, Pedro

    2016-03-27

    The Dlx5 homeodomain is a transcription factor related to the Drosophila distal-less gene that is associated with breast and lung cancer, lymphoma, Rett syndrome and osteoporosis in humans. Mutations in the DLX5 gene have been linked to deficiencies in craniofacial and limb development in higher eukaryotes, including split hand and foot malformation 1 in humans. Our characterization of a Dlx5 homeodomain:(CGACTAATTAGTCG)2 complex by NMR spectroscopy paved the way for determination of its crystal structure at 1.85Å resolution that enabled rationalization of the effects of disease-related mutations on the protein function. A Q186H mutation linked to split hand and foot malformation 1 likely affects affinity of DNA binding by disrupting water-mediated interactions with the DNA major groove. A more subtle effect is implicated for the Q178P mutation, which is not in direct contact with the DNA. Our data indicate that these mutations diminish the ability of the Dlx5 homeodomain to recognize and bind target DNAs, and they likely destabilize the formation of functional complexes. PMID:26829219

  12. Effects of additives in α- and θ-alumina: an ab initio study

    It is of high fundamental and practical importance to be able to control the formation and stability of the different crystalline phases of alumina (Al2O3). In this study, we have used density functional theory methods to investigate the changes induced in the thermodynamically stable α phase and the metastable θ phase as one eighth of the Al atoms are substituted for different additives (Sc, W, Mo, Cr, Cu, Si, and B). The calculations predict that the additives strongly affect the relative stability between the two phases. Most tested additives are shown to shift the relative stability towards, and in some cases completely stabilize, the θ phase, while Cu doping is predicted to increase the relative stability of the α phase. The reasons for these effects are discussed, as are possible implications on the growth and use of doped aluminas in practical applications. In addition, the effects of the additives on bulk moduli and densities of states have been investigated

  13. Effects of phosphate additives on the stability of positive electrolytes for vanadium flow batteries

    Highlights: • A series of phosphates is investigated as additives for vanadium flow battery. • Superior V(V) thermal stability and improved electrochemical performance. • Enhanced battery efficiency and slower capacity fading. • Mechanism for the stabilization and performance improvement is put forward. • NH4H2PO4 indicates a promising candidate for additive of the positive electrolyte. - Abstract: A series of phosphates is investigated as additives to improve the stability of the electrolyte for vanadium flow battery (VFB). Two selected additives show positive effect on the stability of electrolytes under ex-situ stability tests and in situ flow cell experiments. The effects of additives on electrolyte are studied by Nuclear magnetic resonance (NMR), X-ray diffraction (XRD), Raman spectroscopy, Cyclic voltammetry (CV), Electrochemical impedance spectroscopy (EIS) and charge–discharge test. The results show that a VFB using the electrolyte with NH4H2PO4additive demonstrates significantly improved redox reaction reversibility and activity, and higher energy efficiency. In addition, the cell employing the electrolyte with NH4H2PO4 exhibits a charge capacity fading rate much slower than the cell without additives during the cycling at high temperature. These results indicate that the phosphate additives are highly beneficial to improving the stability and reliability of VFB

  14. Deletion mutations of bacteriophage

    Resolution of mutation mechanism with structural changes of DNA was discussed through the studies using bacteriophage lambda. One of deletion mutations inductions of phage lambda is the irradiation of ultraviolet ray. It is not clear if the inductions are caused by errors in reparation of ultraviolet-induced damage or by the activation of int gene. Because the effective site of int gene lies within the regions unnecessary for existing, it is considered that int gene is connected to deletion mutations induction. A certain system using prophage complementarity enables to detect deletion mutations at essential hereditary sites and to solve the relations of deletion mutations with other recombination system, DNA reproduction and repairment system. Duplication and multiplication of hereditary elements were discussed. If lambda deletion mutations of the system, which can control recombination, reproduction and repairment of added DNA, are constructed, mutations mechanism with great changes of DNA structure can be solved by phage lambda. (Ichikawa, K.)

  15. Investigating the effects of dietary folic acid on sperm count, DNA damage and mutation in Balb/c mice

    Swayne, Breanne G.; Kawata, Alice [Environmental Health Science and Research Bureau, Health Canada, Ottawa, Ontario, K1A 0K9 (Canada); Behan, Nathalie A. [Nutrition Research Division, Food Directorate, Health Products and Food Branch, Health Canada, Ottawa, Ontario, K1A 0K9 (Canada); Williams, Andrew; Wade, Mike G. [Environmental Health Science and Research Bureau, Health Canada, Ottawa, Ontario, K1A 0K9 (Canada); MacFarlane, Amanda J. [Nutrition Research Division, Food Directorate, Health Products and Food Branch, Health Canada, Ottawa, Ontario, K1A 0K9 (Canada); Yauk, Carole L., E-mail: carole.yauk@hc-sc.ga.ca [Environmental Health Science and Research Bureau, Health Canada, Ottawa, Ontario, K1A 0K9 (Canada)

    2012-09-01

    To date, fewer than 50 mutagens have been studied for their ability to cause heritable mutations. The majority of those studied are classical mutagens like radiation and anti-cancer drugs. Very little is known about the dietary variables influencing germline mutation rates. Folate is essential for DNA synthesis and methylation and can impact chromatin structure. We therefore determined the effects of folic acid-deficient (0 mg/kg), control (2 mg/kg) and supplemented (6 mg/kg) diets in early development and during lactation or post-weaning on mutation rates and chromatin quality in sperm of adult male Balb/c mice. The sperm chromatin structure assay and mutation frequencies at expanded simple tandem repeats (ESTRs) were used to evaluate germline DNA integrity. Treatment of a subset of mice fed the control diet with the mutagen ethylnitrosourea (ENU) at 8 weeks of age was included as a positive control. ENU treated mice exhibited decreased cauda sperm counts, increased DNA fragmentation and increased ESTR mutation frequencies relative to non-ENU treated mice fed the control diet. Male mice weaned to the folic acid deficient diet had decreased cauda sperm numbers, increased DNA fragmentation index, and increased ESTR mutation frequency. Folic acid deficiency in early development did not lead to changes in sperm counts or chromatin integrity in adult mice. Folic acid supplementation in early development or post-weaning did not affect germ cell measures. Therefore, adequate folic acid intake in adulthood is important for preventing chromatin damage and mutation in the male germline. Folic acid supplementation at the level achieved in this study does not improve nor is it detrimental to male germline chromatin integrity.

  16. Investigating the effects of dietary folic acid on sperm count, DNA damage and mutation in Balb/c mice

    To date, fewer than 50 mutagens have been studied for their ability to cause heritable mutations. The majority of those studied are classical mutagens like radiation and anti-cancer drugs. Very little is known about the dietary variables influencing germline mutation rates. Folate is essential for DNA synthesis and methylation and can impact chromatin structure. We therefore determined the effects of folic acid-deficient (0 mg/kg), control (2 mg/kg) and supplemented (6 mg/kg) diets in early development and during lactation or post-weaning on mutation rates and chromatin quality in sperm of adult male Balb/c mice. The sperm chromatin structure assay and mutation frequencies at expanded simple tandem repeats (ESTRs) were used to evaluate germline DNA integrity. Treatment of a subset of mice fed the control diet with the mutagen ethylnitrosourea (ENU) at 8 weeks of age was included as a positive control. ENU treated mice exhibited decreased cauda sperm counts, increased DNA fragmentation and increased ESTR mutation frequencies relative to non-ENU treated mice fed the control diet. Male mice weaned to the folic acid deficient diet had decreased cauda sperm numbers, increased DNA fragmentation index, and increased ESTR mutation frequency. Folic acid deficiency in early development did not lead to changes in sperm counts or chromatin integrity in adult mice. Folic acid supplementation in early development or post-weaning did not affect germ cell measures. Therefore, adequate folic acid intake in adulthood is important for preventing chromatin damage and mutation in the male germline. Folic acid supplementation at the level achieved in this study does not improve nor is it detrimental to male germline chromatin integrity.

  17. Effects of gamma-irradiation-induced mutation on upland cotton pollen grains

    Despite the demonstrated value of gamma ray as a tool in plant mutation research, in the genetic plant species upland cotton (Gossypium hirsutum L.), such mutations have not been extensively studied. To investigate these questions, the upland cotton cultivar 'Sumian 22' pollen grains were irradiated by gamma rays (20Gy). The irradiation effects on pollen grains were tested considering the ultrastructure changes in the exine and interior walls of pollen grains, their germination rate, DNA polymorphism in the pollen grains, the actin filament in pollen tube, fertilization, and boll development after the pistils were pollinated by the pollen grains which were irradiation with γ-rays. As compared with the control, although the cell structures inside the pollen grain were destroyed, its exine and interior walls of the pollen grain were not etched. The amount and the density of pollen grain inclusions decreased and the size of the lacuna and starch granules increased. Pollen grain germination rate decreased by 37%. The number of pollen tubes in the style declined by 38%, but the growth speed of the tubes did not change. All of the pollen tubes reached the end of the style at 13-h after pollination. This result was consistent with that of the control. Also, the weight and the diameter of the ovary decreased and shortened. No evident change of the fecundation time of ovule was observed. The significant difference on DNA polymorphism was found between irradiation pollen grain and control after pollination by Simple sequence repeats (SSR) molecular marker. The actin filament of the apical domain in pollen tube was destabilized, and in the approximately apical domain, the actin cytoskeleton component disappeared. Various mutants were appeared in the M1 progenies. These results indicate that gamma rays can cause a series of biological changes in irradiated-pollen grains and their progenies of upland cotton. (author)

  18. Effect of dedifferentiation on time to mutation acquisition in stem cell-driven cancers.

    Alexandra Jilkine

    2014-03-01

    Full Text Available Accumulating evidence suggests that many tumors have a hierarchical organization, with the bulk of the tumor composed of relatively differentiated short-lived progenitor cells that are maintained by a small population of undifferentiated long-lived cancer stem cells. It is unclear, however, whether cancer stem cells originate from normal stem cells or from dedifferentiated progenitor cells. To address this, we mathematically modeled the effect of dedifferentiation on carcinogenesis. We considered a hybrid stochastic-deterministic model of mutation accumulation in both stem cells and progenitors, including dedifferentiation of progenitor cells to a stem cell-like state. We performed exact computer simulations of the emergence of tumor subpopulations with two mutations, and we derived semi-analytical estimates for the waiting time distribution to fixation. Our results suggest that dedifferentiation may play an important role in carcinogenesis, depending on how stem cell homeostasis is maintained. If the stem cell population size is held strictly constant (due to all divisions being asymmetric, we found that dedifferentiation acts like a positive selective force in the stem cell population and thus speeds carcinogenesis. If the stem cell population size is allowed to vary stochastically with density-dependent reproduction rates (allowing both symmetric and asymmetric divisions, we found that dedifferentiation beyond a critical threshold leads to exponential growth of the stem cell population. Thus, dedifferentiation may play a crucial role, the common modeling assumption of constant stem cell population size may not be adequate, and further progress in understanding carcinogenesis demands a more detailed mechanistic understanding of stem cell homeostasis.

  19. EF-hand Ca 2+-binding bioluminescent proteins: effects of mutations and alternative divalent cations

    Rowe, Laura; Ensor, Mark; Daunert, Sylvia

    2007-02-01

    Bioluminescent photoproteins, such as aequorin and obelin, are proteins that emit light upon binding calcium. Aequorin and obelin contain four EF-hand domains arranged into a globular structure. The loop region of these EF-hand domains binds calcium by coordinating it in a pentagonal bipyramidal structure with oxygen atoms. The binding of calcium to these EF-hands causes a slight conformational change in the protein, which leads to the oxidation of the internally sequestered chromophore, coelenterazine, producing coelenteramide and CO II. The excited coelenteramide then relaxes radiatively, emitting bioluminescence at 471 nm in aequorin or 491 nm in obelin. Although calcium is the traditional, and generally the most powerful, triggering ligand in this bioluminescence reaction, alternative di- and trivalent cations can also bind to the EF-hand loops and stimulate luminescence. Species capable of this cross-reactivity include: Cd 2+, Ba 2+, Mn 2+, Sr 2+, Mg 2+, and several lanthanides. Magnesium is also known to modulate the bioluminescence of wild-type aequorin, increase its stability, and decrease its aggregation tendency. Both wild-type aequorin and wild-type obelin contain several cysteine residues, aequorin has three and obelin has five. It is believed that these cysteine residues play an important, but as of yet unknown, role in the bioluminescence of these proteins, since mutating most of these residues causes significant loss in bioluminescent activity. In order to explore whether or not these cysteine residues contributed to the specificity of the EF-hand domains for cations we generated four aequorin and obelin mutants and observed their luminescent intensity and decay kinetics by stimulation with calcium, barium, and magnesium. It was found that the cysteine mutations do appear to alter the effects that alternative divalent cations have on the bioluminescence of both aequorin and obelin.

  20. Mutation effects of C{sup 2+} ion irradiation on the greasy Nitzschia sp

    Yang, Y.N., E-mail: ynyangbuaa@gmail.com [School of Chemistry and Environment, Beihang University, 37th Xueyuan Road, Haidian District, P.O. Box 106, 100191 Beijing (China); Liu, C.L.; Wang, Y.K. [School of Chemistry and Environment, Beihang University, 37th Xueyuan Road, Haidian District, P.O. Box 106, 100191 Beijing (China); Xue, J.M. [State Key Lab of Nuclear Physics and Nuclear Technology, Peking University, 100084 Beijing (China)

    2013-11-15

    Highlights: • The optimal conditions of C{sup 2+} ion irradiation on Nitzschia sp. were discussed. • Get the “saddle type” survival curve. • One mutant whose lipid content improved significantly was selected. • The C{sup 2+} ion irradiation didn’t change the algae's morphology and growth rate. - Abstract: Screening and nurturing algae with high productivity, high lipid content and strong stress resistance are very important in algae industry. In order to increase the lipid content, the Nitzschia sp. was irradiated with a 3 MeV C{sup 2+} beam. The sample pretreatment method was optimized to obtain the best mutagenic condition and the survival ratio curve. The positive mutants with a significant improvement in lipid content were screened and their C{sup 2+} mutagenic effects were analyzed by comparing the greasiness and growth characteristics with the wild type algae. Results showed that when the Nitzschia sp. was cultivated in nutritious medium containing 10% glycerol solution, and dried on the filter for 5 min after centrifugation, the realization of the microalgae heavy ion mutagenesis could be done. The survival ratio curve caused by C{sup 2+} irradiation was proved to be “saddle-shaped”. A positive mutant was screened among 20 survivals after irradiation, the average lipid content of the mutation increased by 9.8% than the wild type after 4 generations. But the growth rate of the screened mutation didn’t change after the heavy ion implantation compared to the wild type algae.

  1. Nitrogen Addition Altered the Effect of Belowground C Allocation on Soil Respiration in a Subtropical Forest.

    He, Tongxin; Wang, Qingkui; Wang, Silong; Zhang, Fangyue

    2016-01-01

    The availabilities of carbon (C) and nitrogen (N) in soil play an important role in soil carbon dioxide (CO2) emission. However, the variation in the soil respiration (Rs) and response of microbial community to the combined changes in belowground C and N inputs in forest ecosystems are not yet fully understood. Stem girdling and N addition were performed in this study to evaluate the effects of C supply and N availability on Rs and soil microbial community in a subtropical forest. The trees were girdled on 1 July 2012. Rs was monitored from July 2012 to November 2013, and soil microbial community composition was also examined by phospholipid fatty acids (PLFAs) 1 year after girdling. Results showed that Rs decreased by 40.5% with girdling alone, but N addition only did not change Rs. Interestingly, Rs decreased by 62.7% under the girdling with N addition treatment. The reducing effect of girdling and N addition on Rs differed between dormant and growing seasons. Girdling alone reduced Rs by 33.9% in the dormant season and 54.8% in the growing season compared with the control. By contrast, girdling with N addition decreased Rs by 59.5% in the dormant season and 65.4% in the growing season. Girdling and N addition significantly decreased the total and bacterial PLFAs. Moreover, the effect of N addition was greater than girdling. Both girdling and N addition treatments separated the microbial groups on the basis of the first principal component through principal component analysis compared with control. This indicated that girdling and N addition changed the soil microbial community composition. However, the effect of girdling with N addition treatment separated the microbial groups on the basis of the second principal component compared to N addition treatment, which suggested N addition altered the effect of girdling on soil microbial community composition. These results suggest that the increase in soil N availability by N deposition alters the effect of

  2. Effects of minor alloying additions on the strength and swelling behavior of an austenitic stainless steel

    A set of 32 alloys consisting of various additions of the elements Mo, W, Al, Ti, Nb, C and Si to an Fe-7.5 Cr-20 Ni alloy were made in order to investigate the effects of these solute additions on alloy swelling and strength. Both single and multiple additions were examined. The influence of various solute elements on the swelling behavior in the range 500 to 7300C was investigated using 4 MeV Ni ion bombardment to a dose 170 dpa. It was found that on an atomic percent basis, the elements may be arranged in order of decreasing effectiveness in reducing peak temperature swelling as follows: Ti, C, Nb, Si, and Mo. Small amounts of aluminum enhance swelling. Additions of Si, Ti, or Nb truncate the high temperature swelling regime of the ternary alloy. Mo, W, and C do not have a strong effect on the temperature dependence of swelling. The results may be interpreted in terms of the effect of point defect trapping on void growth rates, and it is suggested that the changes in peak temperature are the result of small changes in the free vacancy formation energy. A method for treating certain multiple additions is proposed. The effect of these alloying additions on short time high temperature strength properties was estimated using hot hardness measurements over the temperature range 22 to 8500C. On an atom percent basis Nb and Ti were most effective in conferring solid solution strengthening and Si the least effective. In the regime 22 to approximately 6500C, the hardness data was found to fit an equation of the form: H = H0 + b/T; where H is the hardness, T is the temperature, and H0 and b are constants for a given alloy. An empirical method was devised to estimate the hot hardness of alloys containing more than one solute addition

  3. The effective use of physical and chemical mutagen in the induction of mutation for crop improvement in Malaysia

    Abdul Rahim Harun [Malaysian Institute for Nuclear Technology Research, Bangi, Selangor (Malaysia)

    2001-03-01

    The earliest work of induced mutations breeding program in Malaysia was reported in 1967. The project was carried out by Rubber Research Institute of Malaysia using x-radiation in an attempt to improve rubber trees for dwarfism and disease resistance. Subsequently, more efforts were taken up by the universities to promote the technology for genetic changes and creation of new genetic resources, particularly in crops that are not easily achievable through conventional techniques. Gamma radiation is always been used as physical mutagen, while ethyl methane sulfonate (EMS) was a popular chemical mutagen used in induced mutation breeding in the country. Gamma rays is an effective mutagen to which more than 30 potential mutants were produced up to now through mutagenesis of several important food crops and ornamental plants. Although chemical mutagen such as EMS were reported being used, the result is not so convincing as compared to gamma radiation. Malaysian Institute for Nuclear Technology Research (MINT) has initiated and promoted nuclear technique in mutation breeding for the improvement of importance food crops such as rice, legume and other potential crops for export, like fruit trees and ornamentals. Gamma radiation is the main source of mutagen used in mutation-breeding programme at MINT. The effectiveness of these two mutagens were verified with mutants derived through induced mutation breeding in the country which some mutant has shown outstanding improvement and released as new varieties and cultivars. This paper summarises and discuss the effects as well as achievement attained through the use of ionizing radiation and chemical mutagen in plant mutation breeding in Malaysia. (author)

  4. The effective use of physical and chemical mutagen in the induction of mutation for crop improvement in Malaysia

    The earliest work of induced mutations breeding program in Malaysia was reported in 1967. The project was carried out by Rubber Research Institute of Malaysia using x-radiation in an attempt to improve rubber trees for dwarfism and disease resistance. Subsequently, more efforts were taken up by the universities to promote the technology for genetic changes and creation of new genetic resources, particularly in crops that are not easily achievable through conventional techniques. Gamma radiation is always been used as physical mutagen, while ethyl methane sulfonate (EMS) was a popular chemical mutagen used in induced mutation breeding in the country. Gamma rays is an effective mutagen to which more than 30 potential mutants were produced up to now through mutagenesis of several important food crops and ornamental plants. Although chemical mutagen such as EMS were reported being used, the result is not so convincing as compared to gamma radiation. Malaysian Institute for Nuclear Technology Research (MINT) has initiated and promoted nuclear technique in mutation breeding for the improvement of importance food crops such as rice, legume and other potential crops for export, like fruit trees and ornamentals. Gamma radiation is the main source of mutagen used in mutation-breeding programme at MINT. The effectiveness of these two mutagens were verified with mutants derived through induced mutation breeding in the country which some mutant has shown outstanding improvement and released as new varieties and cultivars. This paper summarises and discuss the effects as well as achievement attained through the use of ionizing radiation and chemical mutagen in plant mutation breeding in Malaysia. (author)

  5. A prevalent mutation with founder effect in Spanish Recessive Dystrophic Epidermolysis Bullosa families

    Escámez María-José

    2010-09-01

    Full Text Available Abstract Background Recessive Dystrophic Epidermolysis Bullosa (RDEB is a genodermatosis caused by more than 500 different mutations in the COL7A1 gene and characterized by blistering of the skin following a minimal friction or mechanical trauma. The identification of a cluster of RDEB pedigrees carrying the c.6527insC mutation in a specific area raises the question of the origin of this mutation from a common ancestor or as a result of a hotspot mutation. The aim of this study was to investigate the origin of the c.6527insC mutation. Methods Haplotypes were constructed by genotyping nine single nucleotides polymorphisms (SNPs throughout the COL7A1 gene. Haplotypes were determined in RDEB patients and control samples, both of Spanish origin. Results Sixteen different haplotypes were identified in our study. A single haplotype cosegregated with the c.6527insC mutation. Conclusion Haplotype analysis showed that all alleles carrying the c.6527insC mutation shared the same haplotype cosegregating with this mutation (CCGCTCAAA_6527insC, thus suggesting the presence of a common ancestor.

  6. Estimation of direct effects for survival data by using the Aalen additive hazards model

    Martinussen, T.; Vansteelandt, S.; Gerster, M.;

    2011-01-01

    We extend the definition of the controlled direct effect of a point exposure on a survival outcome, other than through some given, time-fixed intermediate variable, to the additive hazard scale. We propose two-stage estimators for this effect when the exposure is dichotomous and randomly assigned...

  7. Effect of rhenium addition on tungsten fuzz formation in helium plasmas

    Khan, A.; De Temmerman, G.; Morgan, T. W.; M. B. Ward,

    2016-01-01

    The effect of the addition of rhenium to tungsten on the formation of a nanostructure referred to as ‘fuzz’ when exposed to helium plasmas at fusion relevant ion fluxes was investigated in the Magnum and Pilot PSI devices at the FOM Institute DIFFER. The effect rhenium had on fuzz growth was seen to

  8. Induced mutations in chickpea (Cicer arietinum L.) I. comparative mutagenic effectiveness and efficiency of physical & chemical mutagens

    Mutagenic effectiveness usually means the rate of mutation as related to dose. Mutagenic efficiency refers to the mutation rate in relation to damage. Studies on comparative mutagenic effectiveness and efficiency of two physical (gamma rays and fast neutrons) and two chemical mutagens (NMU and EMS) on two desi (G 130 & H 214), one kabuli (C 104) and one green seeded (L 345) chickpea (Cicer arietinum L.) have been reported. The treatments included three doses each of gamma rays (400, 500 and 600 Gy) and fast neutrons (5, 10 and 15 Gy) and two concentrations with two different durations of two chemical mutagens, NMU 0.01% 20h and 0.02% 8h) and EMS (0.1% 20h and 0.2% 8h). Results indicated that chemical mutagens, particularly NMU are not only more effective but also efficient than physical mutagens in inducing mutations in chickpea. Mutagenic effectiveness and efficiency showed differential behaviour depending upon mutagen and varietal type. Chemical mutagens were more efficient than physical in inducing cholorophyll as well as viable and total number of mutations. Among the mutagens NMU was the most potent, while in the physical, gamma rays were more effective. Out of four mutagens, NMU was the most effective and efficient in inducing a high frequency and wide spectrum of chlorophyll mutations in the M2 followed by fast neutrons. While gamma rays showed least effectiveness, EMS was least efficient mutagens. Major differences in the mutagenic response of the four cultivars were observed. The varieties of desi type were more resistant towards mutagenic treatment than kabuli and green seeded type

  9. A Restricted Repertoire of De Novo Mutations in ITPR1 Cause Gillespie Syndrome with Evidence for Dominant-Negative Effect.

    McEntagart, Meriel; Williamson, Kathleen A; Rainger, Jacqueline K; Wheeler, Ann; Seawright, Anne; De Baere, Elfride; Verdin, Hannah; Bergendahl, L Therese; Quigley, Alan; Rainger, Joe; Dixit, Abhijit; Sarkar, Ajoy; López Laso, Eduardo; Sanchez-Carpintero, Rocio; Barrio, Jesus; Bitoun, Pierre; Prescott, Trine; Riise, Ruth; McKee, Shane; Cook, Jackie; McKie, Lisa; Ceulemans, Berten; Meire, Françoise; Temple, I Karen; Prieur, Fabienne; Williams, Jonathan; Clouston, Penny; Németh, Andrea H; Banka, Siddharth; Bengani, Hemant; Handley, Mark; Freyer, Elisabeth; Ross, Allyson; van Heyningen, Veronica; Marsh, Joseph A; Elmslie, Frances; FitzPatrick, David R

    2016-05-01

    Gillespie syndrome (GS) is characterized by bilateral iris hypoplasia, congenital hypotonia, non-progressive ataxia, and progressive cerebellar atrophy. Trio-based exome sequencing identified de novo mutations in ITPR1 in three unrelated individuals with GS recruited to the Deciphering Developmental Disorders study. Whole-exome or targeted sequence analysis identified plausible disease-causing ITPR1 mutations in 10/10 additional GS-affected individuals. These ultra-rare protein-altering variants affected only three residues in ITPR1: Glu2094 missense (one de novo, one co-segregating), Gly2539 missense (five de novo, one inheritance uncertain), and Lys2596 in-frame deletion (four de novo). No clinical or radiological differences were evident between individuals with different mutations. ITPR1 encodes an inositol 1,4,5-triphosphate-responsive calcium channel. The homo-tetrameric structure has been solved by cryoelectron microscopy. Using estimations of the degree of structural change induced by known recessive- and dominant-negative mutations in other disease-associated multimeric channels, we developed a generalizable computational approach to indicate the likely mutational mechanism. This analysis supports a dominant-negative mechanism for GS variants in ITPR1. In GS-derived lymphoblastoid cell lines (LCLs), the proportion of ITPR1-positive cells using immunofluorescence was significantly higher in mutant than control LCLs, consistent with an abnormality of nuclear calcium signaling feedback control. Super-resolution imaging supports the existence of an ITPR1-lined nucleoplasmic reticulum. Mice with Itpr1 heterozygous null mutations showed no major iris defects. Purkinje cells of the cerebellum appear to be the most sensitive to impaired ITPR1 function in humans. Iris hypoplasia is likely to result from either complete loss of ITPR1 activity or structure-specific disruption of multimeric interactions. PMID:27108798

  10. SRSF2 Mutations Contribute to Myelodysplasia by Mutant-Specific Effects on Exon Recognition.

    Kim, Eunhee; Ilagan, Janine O; Liang, Yang; Daubner, Gerrit M; Lee, Stanley C-W; Ramakrishnan, Aravind; Li, Yue; Chung, Young Rock; Micol, Jean-Baptiste; Murphy, Michele E; Cho, Hana; Kim, Min-Kyung; Zebari, Ahmad S; Aumann, Shlomzion; Park, Christopher Y; Buonamici, Silvia; Smith, Peter G; Deeg, H Joachim; Lobry, Camille; Aifantis, Iannis; Modis, Yorgo; Allain, Frederic H-T; Halene, Stephanie; Bradley, Robert K; Abdel-Wahab, Omar

    2015-05-11

    Mutations affecting spliceosomal proteins are the most common mutations in patients with myelodysplastic syndromes (MDS), but their role in MDS pathogenesis has not been delineated. Here we report that mutations affecting the splicing factor SRSF2 directly impair hematopoietic differentiation in vivo, which is not due to SRSF2 loss of function. By contrast, SRSF2 mutations alter SRSF2's normal sequence-specific RNA binding activity, thereby altering the recognition of specific exonic splicing enhancer motifs to drive recurrent mis-splicing of key hematopoietic regulators. This includes SRSF2 mutation-dependent splicing of EZH2, which triggers nonsense-mediated decay, which, in turn, results in impaired hematopoietic differentiation. These data provide a mechanistic link between a mutant spliceosomal protein, alterations in the splicing of key regulators, and impaired hematopoiesis. PMID:25965569

  11. Long-Range Effects and Functional Consequences of Stabilizing Mutations in the Ankyrin Repeat Domain of IκBα

    Cervantes, Carla F.; Handley, Lindsey D.; Sue, Shih-Che; Dyson, H. Jane; Komives, Elizabeth A.

    2013-01-01

    Protein domains containing three or more ankyrin repeats (ARs) are ubiquitous in all phyla. Sequence alignments previously identified certain conserved positions, which have been shown to stabilize AR domains and promote their folding. Consensus mutations [Y254L/T257A (YLTA) and C186P/A220P (CPAP)] stabilize the naturally occuring AR domain of human IκBα to denaturation; however, only the YLTA mutations stabilize the protein to proteasomal degradation. We present results from NMR experiments designed to probe the roles of these consensus mutations in IκBα. According to residual dipolar coupling analysis, the gross structures of the AR domains of both mutants appear to be similar to the wild type (WT). Comparison of chemical shifts of mutant and WT proteins reveals that the YLTA and CPAP consensus mutations cause unexpected long-range effects throughout the AR domains. Backbone dynamics experiments reveal that the YLTA mutations in the sixth AR order the C-terminal PEST sequence on the picosecond-to-nanosecond timescale, compared to either the WT or the CPAP mutant IκBαs. This property is likely the mechanism by which the half-life of YLTA IκBα is extended in vivo. PMID:23274114

  12. Effect of PTPRD rs2279776 gene and interaction with hepatitis B virus mutations on the risk of hepatocellular carcinoma

    邓阳

    2014-01-01

    Objective To investigate the effect of rs2279776 at the PTPRD and its interactions on hepatitis B virus(HBV)mutations as well as related risk on hepatocellular carcinoma(HCC).Methods A total of 3023 individ-uals,including 1012 healthy controls,990 HCC-free HBV-infected subjects,and 1021 HBV-caused hepatocellular carcinoma patients(HCC)

  13. Effect of radiation-sensitive mutations and mutagens/carcinogens on bacterial recombination and mutagenesis. Progress report

    Matney, T.S.

    1978-01-01

    Progress is reported on effects of temperature sensitive DNA-initiation mutation in E. coli K-12 mutants; the use of Bacillus subtilis transforming system as an in vitro mutagenesis system; characteristics of the E. coli lysogen used to test the permeability to polycyclic aromatic hydrocarbons; and the genetic toxicology of gentian violet. (PCS)

  14. A comparative study on low-energy ion beam and neutralized beam modifications of naked DNA and biological effect on mutation

    Sarapirom, S.; Thongkumkoon, P.; Prakrajang, K. [Plasma and Beam Physics Research Facility, Department of Physics and Materials Science, Faculty of Science, Chiang Mai University, Chiang Mai 50200 (Thailand); Anuntalabhochai, S. [Molecular Biology Laboratory, Department of Biology, Faculty of Science, Chiang Mai University, Chiang Mai 50200 (Thailand); Yu, L.D., E-mail: yuld@fnrf.science.cmu.ac.th [Plasma and Beam Physics Research Facility, Department of Physics and Materials Science, Faculty of Science, Chiang Mai University, Chiang Mai 50200 (Thailand); Thailand Center of Excellence in Physics, Commission on Higher Education, 328 Si Ayutthaya Road, Bangkok 10400 (Thailand)

    2012-02-01

    DNA conformation change or damage induced by low-energy ion irradiation has been of great interest owing to research developments in ion beam biotechnology and ion beam application in biomedicine. Mechanisms involved in the induction of DNA damage may account for effect from implanting ion charge. In order to check this effect, we used both ion beam and neutralized beam at keV energy to bombard naked DNA. Argon or nitrogen ion beam was generated and extracted from a radiofrequency (RF) ion source and neutralized by microwave-driven plasma in the beam path. Plasmid DNA pGFP samples were irradiated with the ion or neutralized beam in vacuum, followed by gel electrophoresis to observe changes in the DNA conformations. It was revealed that the ion charge played a certain role in inducing DNA conformation change. The subsequent DNA transfer into bacteria Escherichia coli (E. coli) for mutation analysis indicated that the charged ion beam induced DNA change had high potential in mutation induction while neutralized beam did not. The intrinsic reason was attributed to additional DNA deformation and contortion caused by ion charge exchange effect so that the ion beam induced DNA damage could hardly be completely repaired, whereas the neutralized beam induced DNA change could be more easily recoverable owing to absence of the additional DNA deformation and contortion.

  15. Effect of mutations in the A site of 16 S rRNA on aminoglycoside antibiotic-ribosome interaction

    Recht, M I; Douthwaite, S; Dahlquist, K D;

    1999-01-01

    Decoding of genetic information occurs upon interaction of an mRNA codon-tRNA anticodon complex with the small subunit of the ribosome. The ribosomal decoding region is associated with highly conserved sequences near the 3' end of 16 S rRNA. The decoding process is perturbed by the aminoglycoside...... of universally conserved nucleotides at 1406 to 1408 and 1494 to 1495 in the decoding region of plasmid-encoded bacterial 16 S rRNA. Phenotypic changes range from the benign effect of U1406-->A or A1408-->G substitutions, to the highly deleterious 1406G and 1495 mutations that assemble into 30 S subunits...... but are defective in forming functional ribosomes. Changes in the local conformation of the decoding region caused by these mutations were identified by chemical probing of isolated 30 S subunits. Ribosomes containing 16 S rRNA with mutations at positions 1408, 1407+1494, or 1495 had reduced affinity...

  16. Effects of the structural nature of the anionic additives on the rheological behavior of bentonite suspensions

    Different experimental measurements (Theology, granulometry, XRD) were carried out in order to study the main properties of bentonite suspensions in presence of anionic additives at different concentrations. These additives are: Sodium Dodecyl Sulfate (SDS) as surfactant, a flexible polymer (Sodium Carboxy Methyl Cellulose, CMC) and a semi-rigid polymer (Xanthan gum). It has been shown that the structural nature of anionic additive influences directly the mixtures viscoelastic and flow behavior. The steric effect of the surfactant modifies the Face-Edge interactions and yields changes of the mixtures rheological behavior at low deformation rates. Polymers act by coating each clay particle and prevent their agglomeration. Therefore, bentonite has no direct effect on the rheological behavior of the mixtures: the additives are responsible for the mechanisms of de-structuration and structure reorganization as well as the mixtures viscous and viscoelastic behavior. (author)

  17. Effects of different chemical additives on biodiesel fuel properties and engine performance. A comparison review

    Ali Obed Majeed

    2016-01-01

    Full Text Available Biodiesel fuel can be used as an alternative to mineral diesel, its blend up to 20% used as a commercial fuel for the existing diesel engine in many countries. However, at high blending ratio, the fuel properties are worsening. The feasibility of pure biodiesel and blended fuel at high blending ratio using different chemical additives has been reviewed in this study. The results obtained by different researchers were analysed to evaluate the fuel properties trend and engine performance and emissions with different chemical additives. It found that, variety of chemical additives can be utilised with biodiesel fuel to improve the fuel properties. Furthermore, the chemical additives usage in biodiesel is inseparable both for improving the cold flow properties and for better engine performance and emission control. Therefore, research is needed to develop biodiesel specific additives that can be adopted to improve the fuel properties and achieve best engine performance at lower exhaust emission effects.

  18. The effect of enzyme additives on the anaerobic digestion of energy crops

    Brulé, Mathieu

    2014-01-01

    The mechanisms governing the efficiency of commercial fiber-degrading enzyme additives at improving the anaerobic digestion of energy crops were investigated. Standard batch digestion trials (BMP-assays) were performed using the Hohenheim Biogas Test (HBT) on maize straw, maize corn, and rye silage with different inocula. These BMP-assays showed no significant effect of enzyme additives (including commercial cellulase, xylanase, pectinase, laccase) on the methane production rate. However, bat...

  19. Effect of dimethyl sulfoxide addition on ultrasonic degradation of methylene blue

    Shimakage, Kaho; Kobayashi, Daisuke; Naya, Masakazu; Matsumoto, Hideyuki; Shimada, Yuichiro; Otake, Katsuto; Shono, Atsushi

    2016-07-01

    The ultrasonic degradation of methylene blue was carried out in the absence and presence of dimethyl sulfoxide (DMSO) as a radical scavenger for various frequencies, and the effects of DMSO addition on the degradation rate constant estimated by assuming first-order kinetics were investigated. The degradation reaction rate decreased with DMSO addition, and hydroxyl radicals were observed to play important roles in the degradation of methylene blue. However, the degradation reaction did not stop with DMSO addition, and the degradation rate constant in the presence of DMSO was not affected by ultrasonic frequency.

  20. Effects of silica and titania modification additions on the microstructure of sintered alumina

    One studied the effects of material synthesis technique on its phase composition. Phase composition and microstructure of Al2O3-SiO2 system base materials were shown to depend essentially on the way silicon oxide addition was injected. Injection of titanium oxide low additions into Al2O3-SiO2 system affects cardinally the microstructure of sintered material independently of the way it is modified. Combination of the technique of molecular stratifying with injection of addition via mechanical mixing of components enables to prepare materials with regulated porous structure

  1. Effects of different additives on the performance of spray dryer system during incineration process.

    Wey, M Y; Peng, C Y; Wu, H Y; Chiang, B C; Liu, Z S

    2002-06-01

    The spray dryer system was conventionally employed to remove the SOx, NOx, and HCl in the flue gas. However, the removal efficiency of acid gas in the practical incineration flue gas, which contains dust, heavy metals, and acid gas itself, was seldom mentioned in the literature. The alkaline sorbents possess large specific surface that was a main factor on the adsorption of heavy metals and acid gas. Therefore, the primary objective of this study was focused on the effect of different additives on the removal efficiency of acid gas and heavy metals (Cr, Cd and Pb). The mass and element size distribution of heavy metals in fly ash under different additives were also investigated. The results indicated that the removal efficiency of HCl in the spray dryer system was higher than 97.8%. The effects of additives on the removal efficiency of HCl, however, were undistinguished. In the desulfurization process, the highest removal efficiency was 71.3% when the additive of amorphous SiO2 was added in the spray dryer system. The removal efficiency was 66.0% with the additive of CaCl2 and 63.1% without any additives, respectively. It was also found that the spray dryer system could decrease the concentration of metal in fly ash but increase the amount of fly ash. In addition, amorphous SiO2 in the alkaline sorbent tended to increase the adsorption of heavy metal on reactant, because it could enhance the dispersion of alkaline sorbent. PMID:12118621

  2. [Effects of superphosphate addition on NH3 and greenhouse gas emissions during vegetable waste composting].

    Yang, Yan; Sun, Qin-ping; Li, Ni; Liu, Chun-sheng; Li, Ji-jin; Liu, Ben-sheng; Zou, Guo-yuan

    2015-01-01

    To study the effects of superphosphate (SP) on the NH, and greenhouse gas emissions, vegetable waste composting was performed for 27 days using 6 different treatments. In addition to the controls, five vegetable waste mixtures (0.77 m3 each) were treated with different amounts of the SP additive, namely, 5%, 10%, 15%, 20% and 25%. The ammonia volatilization loss and greenhouse gas emissions were measured during composting. Results indicated that the SP additive significantly decreased the ammonia volatilization and greenhouse gas emissions during vegetable waste composting. The additive reduced the total NH3 emission by 4.0% to 16.7%. The total greenhouse gas emissions (CO2-eq) of all treatments with SP additives were decreased by 10.2% to 20.8%, as compared with the controls. The NH3 emission during vegetable waste composting had the highest contribution to the greenhouse effect caused by the four different gases. The amount of NH3 (CO2-eq) from each treatment ranged from 59.90 kg . t-1 to 81.58 kg . t-1; NH3(CO2-eq) accounted for 69% to 77% of the total emissions from the four gases. Therefore, SP is a cost-effective phosphorus-based fertilizer that can be used as an additive during vegetable waste composting to reduce the NH3 and greenhouse gas emissions as well as to improve the value of compost as a fertilizer. PMID:25985667

  3. Effects of Polymeric Additives on the Crystallization and Release Behavior of Amorphous Ibuprofen

    Su Yang Lee

    2013-01-01

    Full Text Available Some polymeric additives were studied to understand their effects on the amorphous phase of ibuprofen (IBU, used as a poorly water soluble pharmaceutical model compound. The amorphous IBU in bulk, as well as in nanopores (diameter ~24 nm of anodic aluminum oxide, was examined with the addition of poly(acrylic acid, poly(N-vinyl pyrrolidone, or poly(4-vinylphenol. Results of bulk crystallization showed that they were effective in limiting the crystal growth, while the nucleation of the crystalline phase in contact with water was nearly instantaneous in all cases. Poly(N-vinyl pyrrolidone, the most effective additive, was in specific interaction with IBU, as revealed by IR spectroscopy. The addition of the polymers was combined with the nanoscopic confinement to further stabilize the amorphous phase. Still, the IBU with addition of polymeric additives showed sustained release behavior. The current study suggested that the inhibition of the crystal nucleation was probably the most important factor to stabilize the amorphous phase and fully harness its high solubility.

  4. Widespread non-additive and interaction effects within HLA loci modulate the risk of autoimmune diseases

    Lenz, Tobias L.; Deutsch, Aaron J.; Han, Buhm; Hu, Xinli; Okada, Yukinori; Eyre, Stephen; Knapp, Michael; Zhernakova, Alexandra; Huizinga, Tom W.J.; Abecasis, Goncalo; Becker, Jessica; Boeckxstaens, Guy E.; Chen, Wei-Min; Franke, Andre; Gladman, Dafna D.; Gockel, Ines; Gutierrez-Achury, Javier; Martin, Javier; Nair, Rajan P.; Nöthen, Markus M.; Onengut-Gumuscu, Suna; Rahman, Proton; Rantapää-Dahlqvist, Solbritt; Stuart, Philip E.; Tsoi, Lam C.; Van Heel, David A.; Worthington, Jane; Wouters, Mira M.; Klareskog, Lars; Elder, James T.; Gregersen, Peter K.; Schumacher, Johannes; Rich, Stephen S.; Wijmenga, Cisca; Sunyaev, Shamil R.; de Bakker, Paul I.W.; Raychaudhuri, Soumya

    2015-01-01

    Human leukocyte antigen (HLA) genes confer strong risk for autoimmune diseases on a log-additive scale. Here we speculated that differences in autoantigen binding repertoires between a heterozygote’s two expressed HLA variants may result in additional non-additive risk effects. We tested non-additive disease contributions of classical HLA alleles in patients and matched controls for five common autoimmune diseases: rheumatoid arthritis (RA, Ncases=5,337), type 1 diabetes (T1D, Ncases=5,567), psoriasis vulgaris (Ncases=3,089), idiopathic achalasia (Ncases=727), and celiac disease (Ncases=11,115). In four out of five diseases, we observed highly significant non-additive dominance effects (RA: P=2.5×1012; T1D: P=2.4×10−10; psoriasis: P=5.9×10−6; celiac disease: P=1.2×10−87). In three of these diseases, the dominance effects were explained by interactions between specific classical HLA alleles (RA: P=1.8×10−3; T1D: P=8.6×1027; celiac disease: P=6.0×10−100). These interactions generally increased disease risk and explained moderate but significant fractions of phenotypic variance (RA: 1.4%, T1D: 4.0%, and celiac disease: 4.1%, beyond a simple additive model). PMID:26258845

  5. Effect of a phytogenic feed additive on the susceptibility of Onchorhynchus mykiss to Aeromonas salmonicida.

    Menanteau-Ledouble, S; Krauss, I; Santos, G; Fibi, S; Weber, B; El-Matbouli, M

    2015-06-29

    In recent years, feed additives have increasingly been adopted by the aquaculture industry. These supplements not only offer an alternative to antibiotics but have also been linked to enhanced growth performance. However, the literature is still limited and provides contradictory information on their effectiveness. This is mainly due to the wide variety of available products and their complex mechanisms of action. Phytogenic feed additives have been shown to have antimicrobial effects and can improve growth performance. In the present study, we investigated the susceptibility of several fish pathogenic bacteria to a phytogenic essential oil product in vitro. In addition, we determined the protective effect of a commercial phytogenic feed additive containing oregano, anis and citrus oils on the resistance of rainbow trout Oncorhynchus mykiss to infection by Aeromonas salmonicida. The bacterium was administered through 3 different routes: intra-peritoneal injection, immersion in a bacterial solution and cohabitation with infected fish. Mortality rates were significantly lower in infected rainbow trout that had received the feed additive: the overall mortality rate across all routes of infection was 18% in fish fed a diet containing the additive compared to 37% in fish that received unsupplemented feed. The route of infection also significantly impacted mortality, with average mortality rates of 60, 17.5 and 5% for intra-peritoneal injection, immersion and cohabitation, respectively. In general, fish were better protected against infection by immersion than infection by injection. PMID:26119300

  6. CO hydrogenation on nickel-based catalysts: Effects of copper addition

    Agnelli, M.; Mirodatos, C.

    2000-05-15

    The effect of copper addition on the catalytic properties of silica-supported nickel catalysts for the reaction of CO hydrogenation in the temperature range of 200--500 C has been investigated. Different effects, positive or negative, depending on the temperature and the copper content, are described and explained. At low temperature (230 C), the addition of low copper content prevents the loss of the active surface by sintering without inhibiting the rate of CO hydrogenation too much. At high temperatures (450 C), high copper content is necessary to limit the accumulation of poisonous carbon products, but at the expense of CO conversion. On the basis of the various kinetic and morphologic effects of copper addition, an advanced description of the CO hydrogenation mechanism is also provided, assuming an active site formed by 2--3 adjacent Ni atoms, whatever the temperature or the copper content may be.

  7. Additivity of semantic and phonological effects: Evidence from speech production in Mandarin.

    Zhu, Xuebing; Zhang, Qingfang; Damian, Markus F

    2016-11-01

    A number of previous studies using picture-word interference (PWI) tasks conducted with speakers of Western languages have demonstrated non-additive effects of semantic and form overlap between pictures and words, which may indicate underlying non-discrete processing stages in lexical retrieval. The present study used Mandarin speakers and presented Chinese characters as distractors. In two experiments, we crossed semantic relatedness with "pure" phonological (i.e., orthographically unrelated) relatedness and found statistically additive effects. In a third experiment, semantic relatedness was crossed with orthographic overlap (phonological overlap was avoided), and once again we found an additive pattern. The results are discussed with regard to possible cross-linguistic differences between Western and non-Western languages in terms of phonological encoding, as well as concerning the locus of relatedness effects in PWI tasks. PMID:26730809

  8. Mechanisms and modeling of the effects of additives on the nitrogen oxides emission

    Kundu, Krishna P.; Nguyen, Hung Lee; Kang, M. Paul

    1991-01-01

    A theoretical study on the emission of the oxides of nitrogen in the combustion of hydrocarbons is presented. The current understanding of the mechanisms and the rate parameters for gas phase reactions were used to calculate the NO(x) emission. The possible effects of different chemical species on thermal NO(x), on a long time scale were discussed. The mixing of these additives at various stages of combustion were considered and NO(x) concentrations were calculated; effects of temperatures were also considered. The chemicals such as hydrocarbons, H2, CH3OH, NH3, and other nitrogen species were chosen as additives in this discussion. Results of these calculations can be used to evaluate the effects of these additives on the NO(x) emission in the industrial combustion system.

  9. Inhibitory effect of aqueous extracts from Miracle Fruit leaves on mutation and oxidative damage.

    Chen, Tai-Yuan; Kang, Zhi-Chyang; Yen, Ming-Tsung; Huang, Ming-Hsing; Wang, Bor-Sen

    2015-02-15

    This study investigated the inhibitory effects of aqueous extracts from Miracle Fruit leaves (AML) on mutation and oxidative damage. The results showed that AML in the range of 1-5mg/plate inhibited the mutagenicity of 2-aminoanthracene (2-AA), an indirect mutagen, and 4-nitroquinoline-N-oxide (4-NQO), a direct mutagen toward Salmonella typhimurium TA 98 and TA 100. On the other hand, AML in the range of 0.05-0.2mg/ml showed radical scavenging, reducing activities, liposome protection as well as decreased tert-butyl hydroperoxide (t-BHP) induced oxidative cytotoxicity in HepG2 cells. High performance liquid chromatography (HPLC) analysis suggested that the active phenolic constituents in AML are p-hydroxybenzoic acid, vanillic acid, syringic acid, trans-p-coumaric acid and veratric acid. These active phenolic components may contribute to the biological protection effects of AML in different models. The data suggest that AML exhibiting biological activities can be applied to antimutation as well as anti-oxidative damage. PMID:25236245

  10. Bioremediation of high organic load lagoon sediments: compost addition and priming effects.

    d'Errico, G; Giovannelli, D; Montano, C; Milanovic, V; Ciani, M; Manini, E

    2013-03-01

    Lagoons are often affected by eutrophication phenomena, due to their shallow nature, high productivity, weak hydrodynamism and anthropic exploitation. Bioremediation techniques have been widely used in the treatment of chemical pollution; however, no information is available on the use of bioremediation of organic-rich sediments. In the present study, we investigated the priming effects following compost addition to organic-rich lagoon sediments, and the effects of this compost addition on degradation and cycling of organic detritus, transfer of organic matter to higher trophic levels, and in situ prokaryotic community structure. There was a positive response to treatment, particularly during the first days after compost addition. The compost had a stimulating effect on degradation activity of the prokaryotic community. This occurred despite an increase in available organic matter, as the community was more efficient at removing it. These data are supported by the prokaryotic community structure analysis, which revealed no changes in the in situ community following compost addition. This priming effect enhancement through compost addition represents an efficient method to treat organic-rich sediments. PMID:23273326

  11. Genomic prediction of growth in pigs based on a model including additive and dominance effects.

    Lopes, M S; Bastiaansen, J W M; Janss, L; Knol, E F; Bovenhuis, H

    2016-06-01

    Independent of whether prediction is based on pedigree or genomic information, the focus of animal breeders has been on additive genetic effects or 'breeding values'. However, when predicting phenotypes rather than breeding values of an animal, models that account for both additive and dominance effects might be more accurate. Our aim with this study was to compare the accuracy of predicting phenotypes using a model that accounts for only additive effects (MA) and a model that accounts for both additive and dominance effects simultaneously (MAD). Lifetime daily gain (DG) was evaluated in three pig populations (1424 Pietrain, 2023 Landrace, and 2157 Large White). Animals were genotyped using the Illumina SNP60K Beadchip and assigned to either a training data set to estimate the genetic parameters and SNP effects, or to a validation data set to assess the prediction accuracy. Models MA and MAD applied random regression on SNP genotypes and were implemented in the program Bayz. The additive heritability of DG across the three populations and the two models was very similar at approximately 0.26. The proportion of phenotypic variance explained by dominance effects ranged from 0.04 (Large White) to 0.11 (Pietrain), indicating that importance of dominance might be breed-specific. Prediction accuracies were higher when predicting phenotypes using total genetic values (sum of breeding values and dominance deviations) from the MAD model compared to using breeding values from both MA and MAD models. The highest increase in accuracy (from 0.195 to 0.222) was observed in the Pietrain, and the lowest in Large White (from 0.354 to 0.359). Predicting phenotypes using total genetic values instead of breeding values in purebred data improved prediction accuracy and reduced the bias of genomic predictions. Additional benefit of the method is expected when applied to predict crossbred phenotypes, where dominance levels are expected to be higher. PMID:26676611

  12. Effect of Prior Bilateral Oophorectomy on the Presentation of Breast Cancer in BRCA1 and BRCA2 Mutation Carriers

    Metcalfe Kelly A

    2005-04-01

    Full Text Available Abstract Purpose To compare the presentation of invasive breast cancer in BRCA1 and BRCA2 mutation carriers with and without prior bilateral oophorectomy. Patients and methods Women with a BRCA1 or BRCA2 mutation with the diagnosis of invasive breast cancer were identified from ten cancer genetics clinics. The medical history, medical treatment records and pathology reports for the breast cancers were reviewed. Information was abstracted from medical charts, including history (and date of oophorectomy, date of breast cancer diagnosis, stage of disease, and pathologic characteristics of the breast cancer. Women with prior bilateral oophorectomy were matched by age, year of diagnosis, and mutation with one or more women who had two intact ovaries at the time of breast cancer diagnosis. Characteristics of the breast tumours were compared between the two groups. Results Women with prior bilateral oophorectomy presented with smaller tumours on average compared to women without prior oophorectomy (mean size 1.50 cm vs. 1.95 cm; p = 0.01. Additionally, although not statistically significant, women with intact ovaries were more likely to have high-grade tumour (70% vs. 54%: p = 0.10 and to have positive lymph nodes (34% vs. 18%; p = 0.11 compared to women with prior bilateral oophorectomy. Conclusions Bilateral oophorectomy prior to breast cancer appears to favourably influence the biological presentation of breast cancer in BRCA1 and BRCA2 mutation carriers.

  13. Radiation graft modification of ethylene-propylene rubber. Pt. 2. Effect of additives

    The effect of multifunctional acrylic additives including TMPTA, PEGDA and PGTA on the radiation grafting of hydrophilic vinyl monomers onto ethylene-propylene elastomer (EPM rubbers) was studied. This work centres upon gamma irradiation-induced grafting of acrylamide (AAm), N-vinyl-2-pyrrolidone (NVP), 2-hydroethyl methacrylate (HEMA) and acrylonitrile (AN) onto EPM rubber by the simultaneous method. Water proved to be an effective solvent but methanol lowered grafting. Sulphuric acid was detrimental to both homopolymerisation and grafting, a result consistent with the theory proposed for the role of this additive in polymer grafting systems. (author)

  14. Radiation graft modification of ethylene-propylene rubber—II. Effect of additives

    Haddadi-Asl, V.; Burford, R. P.; Garnett, J. L.

    1995-02-01

    The effect of multifunctional acrylic additives including TMPTA, PEGDA and PGTA on the radiation grafting of hydrophilic vinyl monomers onto ethylene—propylene elastomer (EPM rubbers) was studied. This work centres upon gamma irradiation-induced grafting of acrylamide (AAm), N-vinyl-2-pyrrolidone (NVP), 2-hydroxyethyl methacrylate (HEMA) and acrylonitrile (AN) onto EPM rubber by the simultaneous method. Water proved to be an effective solvent but methanol lowered grafting. Sulphuric acid was detrimental to both homopolymerisation and grafting, a result consistent with the theory proposed for the role of this additive in polymer grafting systems.

  15. Radicai conversion and crosslinking effects in gamma irradiated isotactic polypropylene with some additives

    The period of conversion from alkyl radicals to polyenyl radicals in gamma-irradiated isotactic polypropylene (i.e. PP) is 108 Mrad, respectively. This indicates that both of the additives inhibit the radiation crosslinking of PP, and hexadecne-1 shows a stronger effect than hexadecane. It was assumed that hexadecene-1 offers its active allyl H atoms to reduce the radical yield of PP, and then inhibit the radiation crosslinking of PP more strongly than hexadecane. However, the whole mechanism related to the effect of the additives on PP radical connversion needs further research

  16. Effect of beryllia substitution and addition in a YBa2Cu3O7-δ compound

    The effect of BeO substitution and addition in the superconducting properties of YBa2Cu3O7-δ superconductors has been investigated by temperature resistance measurements and x-ray diffraction studies. The results revealed that the substitution or addition of BeO in YBa2Cu3O7-δ does not have much detrimental effect on the superconducting properties. Because of this nonpoisoning behavior, beryllia is suggested as a suitable substrate material for the production of superconducting thin films

  17. Improvement of shape memory effect in Fe-Mn-Si alloy by slight tantalum addition

    The effects of slight tantalum (Ta) addition on the microstructures, precipitates, martensitic transformation and shape memory performance of Fe-30Mn-6Si-based alloys were investigated. Experimental results show that the slight Ta addition will increase the c/a ratio of ε martensite, reduce the Ms temperature and improve the alloy's shape recovery ability. After TMT at 650 deg. C, the alloy's Ms temperature is reduced and lots of (Fe, Mn)3Si and TaC precipitates form. The effective nuclei and well-aligned precipitates within the grain interior after TMT will improve significantly the alloy's shape memory performance.

  18. Assessment of Site Specific Mutational Effect on Transcription Initiation at Escherichia coli Promoter

    S. Kannan

    2009-01-01

    Full Text Available Problem statement: It is widely accepted thought that the weak promoters control the RNA synthesis and play regulatory role in complex genetic networks in bacterial system. An experiment had been designed to address whether mutations in the -16/-17 region affect the rate of transcription at an activator-independent promoter in E. coli or not? Approach: The aim of this study was to determine whether mutations in the -16/-17 region affect the rate of expression at an activator-dependent promoter in JM109 strain of E. coli. Primers were constructed to amplify the mutant promoter genes through PCR. The amplified PCR product was checked and then inserted into the MCS region of pAA128 plasmid. Further the plasmid vector was transformed into JM109 strain of E. coli and then cloned the selected transformats. Finally, the plasmid from each mutant colony was then sequenced using the protocol supplied with the Amersham Pharmacia Biotech T7 sequencing Kit. The JM109 cultures for which the sequences were determined, then assayed for ß-galactosidase activity to assess the rate of gene expression from the altered promoters. Results: The present investigation revealed that the extended-10 promoter region has a substantial effect on the rate of transcription at weak promoter sequence and also bearing little resemblance to the consensus sequence recognized by RNA. The expression of the genetically engineered plasmid proved that the 2 bps (-16 and -17 base pair found adjacently upstream of the extended-10 promoter have an effect on the level of transcription. This was achieved by site specific base substitutions into the weak promoter of a modified lac operon lacking any activator or repressor binding sites. The results from gene expression assays of several mutants showed a distinct preference for either GG or TT located adjacently upstream of the extended promoter element. Thus the present study emphasized that

  19. Long range dynamic effects of point-mutations trap a response regulator in an active conformation

    Bobay, Benjamin G.; Thompson, Richele J.; Hoch, James A.; Cavanagh, John

    2010-01-01

    When a point-mutation in a protein elicits a functional change, it is most common to assign this change to local structural perturbations. Here we show that point-mutations, distant from an essential highly dynamic kinase recognition loop in the response regulator Spo0F, lock this loop in an active conformation. This ‘conformational trapping’ results in functionally hyperactive Spo0F. Consequently, point-mutations are seen to affect functionally critical motions both close to and far from the...

  20. Functional effects of KCNE3 mutation and its role in the development of Brugada syndrome

    Delpón, Eva; Cordeiro, Jonathan M; Núñez, Lucía;

    2008-01-01

    INTRODUCTION: The Brugada Syndrome (BrS), an inherited syndrome associated with a high incidence of sudden cardiac arrest, has been linked to mutations in four different genes leading to a loss of function in sodium and calcium channel activity. Although the transient outward current (I(to)) is...... thought to play a prominent role in the expression of the syndrome, mutations in I(to)-related genes have not been identified as yet. METHODS AND RESULTS: One hundred and five probands with BrS were screened for ion channel gene mutations using single strand conformation polymorphism (SSCP...

  1. Effects of carbon additives on the performance of negative electrode of lead-carbon battery

    Highlights: • The negative electrode sheets are prepared by simulating manufacture condition of negative plates. • The effect of carbon additives on negative electrode sheets is studied by electrochemical method. • Carbon additives in NAM enhance electrochemical properties of the negative sheets. • The negative sheets with 0.5 wt% carbon additive exhibit better electrochemical performance. • The charge-discharge mechanism is discussed in detail according to the experimental results. - Abstract: In this study, carbon additives such as activated carbon (AC) and carbon black (CB) are introduced to the negative electrode to improve its electrochemical performance, the negative electrode sheets are prepared by simulating the negative plate manufacturing process of lead-acid battery, the types and contents of carbon additives in the negative electrode sheets are investigated in detail for the application of lead-carbon battery. The electrochemical performance of negative electrode sheets are measured by chronopotentiometry, galvanostatic charge-discharge and electrochemical impedance spectroscopy, the crystal structure and morphology are characterized by X-ray diffraction and scanning electron microscopy, respectively. The experimental results indicate that the appropriate addition of AC or CB can enhance the discharge capacity and prolong the cycle life of negative electrode sheets under high-rate partial-state-of-charge conditions, AC additive exerts more obvious effect than CB additive, the optimum contents for the best electrochemical performance of the negative electrode sheets are determined as 0.5wt% for both AC and CB. The reaction mechanism of the electrochemical process is also discussed in this paper, the appropriate addition of AC or CB in negative electrode can promote the conversion of PbSO4 to Pb, suppress the sulfation of negative electrode sheets and reduce the electrochemical reaction resistance

  2. Casein SNP in Norwegian goats: additive and dominance effects on milk composition and quality

    Lien Sigbjørn

    2011-08-01

    Full Text Available Abstract Background The four casein proteins in goat milk are encoded by four closely linked casein loci (CSN1S1, CSN2, CSN1S2 and CSN3 within 250 kb on caprine chromosome 6. A deletion in exon 12 of CSN1S1, so far reported only in Norwegian goats, has been found at high frequency (0.73. Such a high frequency is difficult to explain because the national breeding goal selects against the variant's effect. Methods In this study, 575 goats were genotyped for 38 Single Nucleotide Polymorphisms (SNP located within the four casein genes. Milk production records of these goats were obtained from the Norwegian Dairy Goat Control. Test-day mixed models with additive and dominance fixed effects of single SNP were fitted in a model including polygenic effects. Results Significant additive effects of single SNP within CSN1S1 and CSN3 were found for fat % and protein %, milk yield and milk taste. The allele with the deletion showed additive and dominance effects on protein % and fat %, and overdominance effects on milk quantity (kg and lactose %. At its current frequency, the observed dominance (overdominance effects of the deletion allele reduced its substitution effect (and additive genetic variance available for selection in the population substantially. Conclusions The selection pressure of conventional breeding on the allele with the deletion is limited due to the observed dominance (overdominance effects. Inclusion of molecular information in the national breeding scheme will reduce the frequency of this deletion in the population.

  3. Effect of inorganic additive sodium pyrophosphate tetrabasic on positive electrolytes for a vanadium redox flow battery

    Sodium pyrophosphate tetrabasic (SPT) is employed as an inorganic additive in the positive electrolyte of a vanadium redox flow battery (VRFB) to improve its long-term stability and electrochemical performance. The results of precipitation tests show that the long-term stability of positive electrolytes (2 MV(V) solution in 4 M total sulfates with 0.05 M SPT additive) is improved compared to the blank one. UV-vis and cyclic voltammetry (CV) measurements also suggest that the addition of SPT can effectively delay the formation of precipitation in positive electrolytes, and no new substances are formed in V(V) electrolytes with SPT. The calcined precipitates extracted from the electrolytes with and without a SPT additive are identified as V2O5 by X-ray diffraction (XRD) analysis. A VRFB single-unit cell employing positive electrolytes with an additive exhibits the high energy efficiency of 74.6% at a current density of 40 mA cm2 at the 500th cycle at 20°C, compared to 71.8% for the cell employing the electrolyte without an additive. Moreover, the cell employing the electrolyte with an additive exhibits less discharge capacity fading during cycling in comparison with the pristine one. The disassembled cell without an additive shows a large number of V2O5 precipitation particles on the felt electrode after 500 cycles. Meanwhile, the felt electrode of the cell with an additive has little precipitation. That precipitation gives rise to an imbalance between the positive and negative half-cell electrolytes, which results in a significant capacity loss. The additive has shown positive results under limited laboratory short-term and small-scale conditions

  4. Effect of Mixed Solvents and Additives on the Habit Modification of 6-APA Crystals

    GONG Junbo; WANG Jingkang; WEI Hongyuan

    2005-01-01

    6-aminopenicillanic acid (6-APA) crystals obtained under different physical and chemical conditions of the solutions may present different habits. The habits of diamond-shaped plates are desirable compared with other habits of 6-APA crystals. To obtain ideal 6-APA crystals, the effects of the mixed solvents and additives on 6-APA crystal habits were investigated. Ethanol or acetone was used as the organic solvent, and impurities existing in the 6-APA purification process were used as the additives. 6-APA growth habits were changed when the concentrations of ethanol, acetone or phenyl acetic acid were increased to exceed their critical concentration. The observed results show that the dominant face on 6-APA crystals was identified to be {020}, but the overall habit was controlled by the relative growth rates of the {101} and {002} faces. Crystal growth rates and habits can be appreciably changed by specific adsorption of additives on crystal faces.In some cases solvent molecules can act in a similar way and may be regarded as bulk additives. The effects of additives and organic solvents on 6-APA crystal habits were the results of adsorption effect, which fitted the experimental results quite well.

  5. Effect of dispersing and stabilizing additives on rheological characteristics of the upgraded brown coal water mixture

    Umar, Datin Fatia; Muta' alim [Research and Development Center for Mineral and Coal Technology, Jalan Jenderal Sudirman No. 623 Bandung 40211 (Indonesia); Usui, Hiromoto; Komoda, Yoshiyuki [Department of Chemical Science and Engineering, Kobe University, 1-1 Rokkodai-cho, Nada-ku, Kobe 657-8501 (Japan)

    2009-04-15

    Upgraded brown coal water mixture (UBCWM) preparation by using an Indonesian upgraded coal produced by upgraded brown coal (UBC) process, was carried out to study the effect of dispersing and stabilizing additives on rheological behavior of the UBCWM. Three kinds of anionic dispersing additives, naphthalene sulfonic formaldehyde condensate (NSF), poly (meth) acrylate (PMA) and poly styrene sulfonic acid (PSS) and three kinds of stabilizing additives, carboxyl methyl cellulose (CMC), rhansam gum (S-194) and gellan gum (S-60) were used in this study. Results indicate that the addition of NSF 0.3 wt.% together with S-194 0.01 wt.% is effective in preparing UBCWM with good slurryability and stability, based on its rheological characteristics with the apparent viscosity at shear rate of 100 s{sup -} {sup 1} and yield stress at zero point of shear rate. The rheological behavior of all of the UBCWM that prepared, exhibits non-Newtonian Bingham plastic. From the economical point of view, the price of S-194 is expensive. On the other hand, CMC is cheap and abundant. Therefore, the addition of CMC 0.01 wt.% together with NSF 0.3 wt.% is also effective in preparing UBCWM with good fluidity and stability. (author)

  6. The effect of lactic acid bacterial starter culture and chemical additives on wilted rice straw silage.

    Wang, Yan-Su; Shi, Wei; Huang, Lin-Ting; Ding, Cheng-Long; Dai, Chuan-Chao

    2016-04-01

    Lactic acid bacteria (LAB) are suitable for rice straw silage fermentation, but have been studied rarely, and rice straw as raw material for ensiling is difficult because of its disadvantages, such as low nutrition for microbial activities and low abundances of natural populations of LAB. So we investigated the effect of application of LAB and chemical additives on the fermentation quality and microbial community of wilted rice straw silage. Treatment with chemical additives increased the concentrations of crude protein (CP), water soluble carbohydrate (WSC), acetic acid and lactic acid, reduced the concentrations of acid detergent fiber (ADF) and neutral detergent fiber (NDF), but did not effectively inhibit the growth of spoilage organisms. Inoculation with LABs did not improve the nutritional value of the silage because of poor growth of LABs in wilted rice straw. Inoculation with LAB and addition of chemical materials improved the quality of silage similar to the effects of addition of chemical materials alone. Growth of aerobic and facultatively anaerobic bacteria was inhibited by this mixed treatment and the LAB gradually dominated the microbial community. In summary, the fermentation quality of wilted rice straw silage had improved by addition of LAB and chemical materials. PMID:26429595

  7. Effect of H2 addition on combustion characteristics of dimethyl ether jet diffusion flame

    Highlights: • DME- and H2-dominated combustion regimes were quantitatively characterized. • The flame structure changed significantly when H2 addition was above 60 vol.%. • An empirical correlation for normalized flame entrainment rate was developed. • The optimal H2 addition to DME was 60 vol.% in the practical engineering. - Abstract: In this paper, experiments and numerical calculations were conducted to investigate the effect of H2 addition on dimethyl ether (DME) jet diffusion flame behaviors, in terms of thermal and chemical structures, reaction zone size, flame entrainment, and NOx and CO emission indices. A wide range of H2 additions from pure DME to pure H2 were involved herein, while maintaining the volumetric flow rate of fuel mixture constant. The results indicate that when H2 mole fraction in the fuel mixture exceeded 60%, the blended fuel was converted to H2-dominated. Besides, the flames behaved rather distinctly at the DME- and H2-dominated regimes. With the increment in H2 addition, flame temperature, H2, H, O, and OH concentrations increased gradually, but concentrations of the intermediate hydrocarbons (such as CO, CH2O, CH2, and CH3) decreased on the contrary. Additionally, after the flame became H2-dominated, the species concentrations varied increasingly quickly with H2 addition. The reaction zone length and width decreased nearly linearly with H2 addition at the DME- and H2-dominated regimes. But the decreasing speed of reaction zone length became faster after the flame was converted to H2-dominated. At the DME-dominated regime, the dependence of flame entrainment coefficient (Ce) on H2 addition was rather small. While at the H2-dominated regime, Ce increased increasingly quickly with H2 addition. Moreover, with the increment in H2 addition, NOx emission index increased and CO emission index decreased gradually. In addition, at the DME-dominated regime, NOx emission index increased fairly slowly with H2 addition; while at the H2

  8. The Nonlinear Structure of the Desmoplakin Plakin Domain and the Effects of Cardiomyopathy-Linked Mutations

    C. Al-Jassar; T. Knowles; M. Jeeves; K. Kami; E. Behr; H. Bikker; M. Overduin; M. Chidgey

    2011-01-01

    Desmoplakin is a cytoplasmic desmosomal protein that plays a vital role in normal intercellular adhesion. Mutations in desmoplakin can result in devastating skin blistering diseases and arrhythmogenic right ventricular cardiomyopathy, a heart muscle disorder associated with ventricular arrhythmias,

  9. Additive Effect on the Electrochemical Performance of Lithium–Sulfur Battery

    Lithium difluoro(oxalato) borate (LiDFOB) was investigated as an electrolyte additive for the Li-S battery. This additive was identified to be an efficient electrolyte additive to suppress the polysulfide shuttling effect existing in the conventional Li–S chemistry. To detect the positive impact of the new additive, oligo(ethylene glycol) functionalized silane was employed as the electrolyte solvent due to its high solvation capability with the lithium polysulfides. The electrochemical results and the SEM data of Li–S battery using the new electrolyte confirmed the role of the LiDFOB as a critical component to eliminate the shuttling of the dissolved polysulfides thus enabling a high coulombic efficiency

  10. Effects of TFA addition on the growth of sintered YBa2Cu3Oy superconductors

    Kita, Ryusuke; Kuroda, Keita; Kato, Teppei; Miura, O.; Yamada, K.; Kaneko, K.

    The effects of trifluoroacetic acid (TFA) addition on the growth of a superconducting phase in sintered YBCO samples were investigated. YBCO samples with TFA addition were prepared by adding TFA (99.0%) to YBCO powder and then pressed into pellets and heated 1173 K - 1213 K for 12 - 20 hr in air. After the heat treatment, the TFA-added sample showed large grain sizes and highly c-axis oriented structures compared to pure YBCO samples, which indicates the enhancement of the grain growth of YBCO sintered samples by the TFA addition. The Jc (0) value and Jc/Jc (0T) properties of the sintered samples was improved by the TFA addition.

  11. Effect of fructo-oligosaccharide and isomalto-oligosaccharide addition on baking quality of frozen dough.

    Park, Eun Young; Jang, Sung-Bum; Lim, Seung-Taik

    2016-12-15

    The baking quality of frozen doughs containing different levels of fructo-oligosaccharides (FO) or isomalto-oligosaccharides (IMO) (3-9%, w/w flour), and stored for 0-8weeks at -18°C, was examined. The addition of FO or IMO increased the proof volume of the dough and the loaf volume of bread prepared from frozen dough. A 6% addition of FO or IMO was optimum, giving the highest proof volume and bread loaf volume, but a higher concentration than 6% induced low baking quality including lower proof volume and bread loaf volume. The bread crumb was moister and softer after the addition of FO or IMO before, and even after, frozen storage. Darker crumb colour was observed in the bread after the addition of FO or IMO. The oligosaccharides added to the frozen dough were effective in improving the quality of bread made from frozen dough, except for resulting in a darker bread crumb. PMID:27451167

  12. Effect of Additives on UV-activated Urethane Acrylate Polymerization Composite Coatings

    Zane GRIGALE-SOROCINA

    2016-05-01

    Full Text Available An increased demand for new and improved coating systems, for environmental & health & safety and performance reasons, have appeared during the recent decades. Currently, there is new interest in preparation of thin UV curable urethane acrylate (UA composite coatings with short-term properties. Cellulose based additives: nitrocellulose, cellulose acetate butyrate, sucrose benzoate and silica were evaluated to determine their influence on unreacted composite characteristics (viscosity, pigment suspension stability and characteristics of cured film (ultimate tensile strength, elongation at break, surface gloss, surface scratch resistance and film adhesion loss time. The most suitable additive content was found to provide required viscosity. All additives increase surface scratch resistance, but cellulose based additives increase surface gloss values and decrease the time of adhesion loss. Silica has great effect on the interaction between linear and hyperbranched urethane acrylates, which has crucial influence on the stability of uncured pigmented mixture samples.

  13. Effect of amino acid additives on crystal growth parameters and properties of ammonium dihydrogen orthophosphate crystals

    Ammonium dihydrogen orthophosphate (ADP) crystals were grown with amino acid materials L-arginine monohydrochloride and L-alanine as new additives in different molar concentrations. The metastable zonewidth of ADP solution with and without these additives was determined and compared. Induction periods for nucleation as a function of supersaturation in different concentrations of additives were measured. Nucleation studies show that metastable zonewidth and induction period of ADP are enhanced by the addition of these amino acids. With increasing additive concentration, the growth rate was found to increase. Amino acid added ADP crystals were grown from the aqueous solution with a simple apparatus that can be applied in certain forced convection configurations to maintain a higher homogeneity of the solution. Moreover, the addition of these amino acids improves the quality of the crystal and yields highly transparent crystals with well-defined features. The high-resolution X-ray diffraction (XRD) analysis reveals that the crystalline perfection of these amino acid doped ADP crystals is extremely good without having any internal structural grain boundaries and mosaic nature. The effect of additives on the growth, nucleation kinetics, structural, optical and mechanical properties has been investigated

  14. Effect of Fuel Additives on Spray Performance of Alternative Jet Fuels

    Kannaiyan, Kumaran; Sadr, Reza

    2015-11-01

    Role of alternative fuels on reducing the combustion pollutants is gaining momentum in both land and air transport. Recent studies have shown that addition of nanoscale metal particles as fuel additives to liquid fuels have a positive effect not only on their combustion performance but also in reducing the pollutant formation. However, most of those studies are still in the early stages of investigation with the addition of nanoparticles at low weight percentages. Such an addition can affect the hydrodynamic and thermo-physical properties of the fuel. In this study, the near nozzle spray performance of gas-to-liquid jet fuel with and without the addition of alumina nanoparticles are investigated at macro- and microscopic levels using optical diagnostic techniques. At macroscopic level, the addition of nanoparticles is seen to enhance the sheet breakup process when compared to that of the base fuel. Furthermore, the microscopic spray characteristics such as droplet size and velocity are also found to be affected. Although the addition of nanoscale metal particles at low weight percentages does not affect the bulk fluid properties, the atomization process is found to be affected in the near nozzle region. Funded by Qatar National Research Fund.

  15. The effect of water plant extracts addition on the oxidative stability of meat products

    Karolina M. Wójciak; Zbigniew J.Dolatowski; Anna Okoń

    2011-01-01

    Background. Natural antioxidants extracted from plants have a lot of antioxidants catechins, epigallocatechins (green tea) rosmariquinone, rosmaridiphenol (rosemary), capsaicinoids (red pepper). They can be used as alternatives to the synthetic antioxidants because of their equivalence or greater effect on inhibition of lipid oxidation and haem pigment (nitrosohemachrome) protection. The aim of the study was to compare the effect of addition of green tea extract, red pepper extract and ...

  16. EFFECT OF METALLOID COMPOUND AND BIO-SOLUTION ADDITIVES ON BIODIESEL ENGINE PERFORMANCE AND EXHAUST EMISSIONS

    Karoon Fangsuwannarak

    2013-01-01

    Full Text Available The purpose of this study is to perform comparative analysis of the effect of the different fuel additives as polymer based-bio-solution, natural organic based-bio-solution and nano-titanium metalloid (TiO2 compound on the performance parameters and exhuast emissions of a pickup Diesel engine, operating on commercial Diesel fuel (D and B5 palm biodiesel (95% D+5% palm oil. The basic properties of the fuel blended with TiO2 metalloid compound and bio-solution based additives were measured according to ASTM standard. Engine performance of a pickup diesel engine was investigated by testing on a chassis dynamometer with the simulation of road load condition. It was found that TiO2 based-additive is more effective for improving engine power than pure Diesel and B5 fuels by 7.78% and 1.36%, respectively. Meanwhile, with using TiO2 additive, the maximum engine torque on average increased by 1.01% and 1.53% in the wide range between 1,700 and 3,000 rpm as compared with Diesel and B5 fuels, respectively. The TiO2 and natural organic additives is significantly effective on Diesel fuel for reducing brake specific fuel consumption reached by 13.22% and 10.01%, respectively as compared with pure Diesel. Moreover, the exhuast emissions (NOx, CO and CO2 decreased from the engine using the TiO2 additive in Diesel fuel and natural organic additive in Diesel fuel.

  17. Pitting corrosion behaviour of austenitic stainless steels - combining effects of Mn and Mo additions

    Mn and Mo were introduced in AISI 304 and 316 stainless steel composition to modify their pitting corrosion resistance in chloride-containing media. Corrosion behaviour was investigated using gravimetric tests in 6 wt.% FeCl3, as well as potentiodynamic and potentiostatic polarization measurements in 3.5 wt.% NaCl. Additionally, the mechanism of the corrosion attack developed on the material surface was analysed by scanning electron microscopy (SEM), X-ray mapping and energy dispersive X-ray (EDX) analysis. The beneficial effect of Mo additions was assigned to Mo6+ presence within the passive film, rendering it more stable against breakdown caused by attack of aggressive Cl- ions, and to the formation of Mo insoluble compounds in the aggressive pit environment facilitating the pit repassivation. Conversely, Mn additions exerted an opposite effect, mainly due to the presence of MnS inclusions which acted as pitting initiators

  18. Additional Interventions to Enhance the Effectiveness of Individual Placement and Support: A Rapid Evidence Assessment

    Naomi Boycott

    2012-01-01

    Full Text Available Topic. Additional interventions used to enhance the effectiveness of individual placement and support (IPS. Aim. To establish whether additional interventions improve the vocational outcomes of IPS alone for people with severe mental illness. Method. A rapid evidence assessment of the literature was conducted for studies where behavioural or psychological interventions have been used to supplement standard IPS. Published and unpublished empirical studies of IPS with additional interventions were considered for inclusion. Conclusions. Six published studies were found which compared IPS alone to IPS plus a supplementary intervention. Of these, three used skills training and three used cognitive remediation. The contribution of each discrete intervention is difficult to establish. Some evidence suggests that work-related social skills and cognitive training are effective adjuncts, but this is an area where large RCTs are required to yield conclusive evidence.

  19. Effect of urea addition on the radiation vulcanisation of natural rubber latex

    Acrylate monomers have been in recent years to reduce the radiation dose required to vulcanise natural rubber latex, originally 300 kGy to 15 kGy. However, there is still a need to further reduce the dose requirement without increasing the sensitiser concentration. In the present study, the synergistic effect of addition of urea along with the sensitiser n-butyl acrylate (n-BA) on the crosslinking density and mechanical properties of radiation vulcanised natural rubber (RVNRL) film has been investigated. The results show that by addition of 0.2 part hundred rubber (phr) urea to the latex before irradiation, the crosslinking density and tensile strength increases by about 15% and 47% respectively. This increase has been attributed to the higher concentration of the sensitiser n-butyl acrylate in the rubber phase in presence of urea. The effects of urea addition on the ageing properties of the latex are being investigated. (author). 6 refs., 3 figs., 1 tab

  20. A novel SOD1-ALS mutation separates central and peripheral effects of mutant SOD1 toxicity

    Joyce, Peter I.; McGoldrick, Philip; Saccon, Rachele A.; Weber, William, L.; Fratta, Pietro; West, Steven J.; Zhu, Ning; Carter, Sarah; Phatak, Vinaya; Stewart, Michelle; Simon, Michelle; Kumar, Saumya; Heise, Ines; Bros-Facer, Virginie; Dick, James

    2014-01-01

    Transgenic mouse models expressing mutant superoxide dismutase 1 (SOD1) have been critical in furthering our understanding of amyotrophic lateral sclerosis (ALS). However, such models generally overexpress the mutant protein, which may give rise to phenotypes not directly relevant to the disorder. Here, we have analysed a novel mouse model that has a point mutation in the endogenous mouse Sod1 gene; this mutation is identical to a pathological change in human familial ALS (fALS) which results...

  1. Effects of Ga Addition on Interfacial Reactions Between Sn-Based Solders and Ni

    Wang, Chao-Hong; Li, Kuan-Ting

    2016-07-01

    The use of Ga as a micro-alloying element in Sn-based solders can change the microstructure of solder joints to improve the mechanical properties, and even suppress the interfacial intermetallic compound (IMC) growth. This research investigated the effects of Ga addition (0.2-1 wt.%Ga) on the IMC formation and morphological evolution in the Sn-based solder joints with Ni substrate. In the soldering reaction at 250°C and with less than 0.2 wt.%Ga addition, the formed phase was Ni3Sn4. When the Ga addition increased to 0.5 wt.%, it changed to a thin Ni2Ga3 layer of ˜1 μm thick, which stably existed at the interface in the initial 1-h reaction. Subsequently, the whole Ni2Ga3 layer detached from the Ni substrate and drifted into the molten solder. The Ni3Sn4 phase became dominant in the later stage. Notably, the Ga addition significantly reduced the grain size of Ni3Sn4, resulting in the massive spalling of Ni3Sn4 grains. With 1 wt.%Ga addition, the Ni2Ga3 layer remained very thin with no significant growth, and it stably existed at the interface for more than 10 h. In addition, the solid-state reactions were examined at temperatures of 160°C to 200°C. With addition of 0.5 wt.%Ga, the Ni3Sn4 phase dominated the whole reaction. By contrast, with increasing to 1 wt.%Ga, only a thin Ni2Ga3 layer was found even after aging at 160°C for more than 1200 h. The 1 wt.%Ga addition in solder can effectively inhibit the Ni3Sn4 formation in soldering and the long-term aging process.

  2. The Effectiveness of an Additional Stretching Exercise Program in Improving Flexibility Level among Preschool Boys

    Lee, Wee Akina Sia Seng; Rengasamy, Shabeshan A/L; Raju, Subramaniam A/L

    2014-01-01

    This study was conducted to examine the effectiveness of a two minutes' additional stretching exercise program in a 30 minutes games teaching lesson in improving the flexibility level of 6 year old preschool boys (M = 5.92, SD = 0.27) in a preschool in Malaysia. Fifty (50) preschool boys were selected for the study based on the intact sampling…

  3. The cost-effectiveness of HPV vaccination in addition to screening : a Dutch perspective

    Setiawan, Didik; Luttjeboer, Jos; Westra, Tjalke Arend; Wilschut, Jan C.; Suwantika, Auliya A.; Daemen, Toos; Atthobari, Jarir; Wilffert, Bob; Postma, Maarten J.

    2015-01-01

    Addition of the HPV vaccine to available cytological screening has been proposed to increase HPV-related cancer prevention. A comprehensive review on this combined strategy implemented in the Netherlands is lacking. For this review, we therefore analyzed all relevant studies on cost-effectiveness of

  4. Effect of crushed mussel shell addition on bacterial growth in acid polluted soils

    Fernandez Calviño, David; Garrido-Rodríguez, B.; Arias-Estévez, M.;

    2015-01-01

    We applied three different doses of crushed mussel shell (CMS) on two Cu-polluted acid soils to study the effect of these amendments on the growth of the bacterial community during 730 days. Soil pH increased in the short and medium term due to CMS addition. In a first stage, bacterial growth was...

  5. Additive Effects of Stimulus Quality and Word Frequency on Eye Movements during Chinese Reading

    Liu, Pingping; Li, Xingshan; Han, Buxin

    2015-01-01

    Eye movements of Chinese readers were recorded for sentences in which high- and low-frequency target words were presented normally or with reduced stimulus quality in two experiments. We found stimulus quality and word frequency produced strong additive effects on fixation durations for target words. The results demonstrate that stimulus quality…

  6. Anthelmintic effects of phytogenic feed additives in Ascaris suum inoculated pigs

    Krimpen, van M.M.; Binnendijk, G.P.; Borgsteede, F.H.M.; Gaasenbeek, C.P.H.

    2010-01-01

    Two experiments were performed to determine the anthelmintic effect of some phytogenic feed additives on a mild infection of Ascaris suum in growing and finishing pigs. Usually, an infection of A. suum is controlled by using conventional synthetic drugs. Organic farmers, however, prefer a non-pharma

  7. Solvent effect on Rb+ to K+ ion mutation: Monte Carlo simulation study

    The solvent effects on the relative free energies of solvation and the difference in partition coefficients (log P) for Rb+ to K+ mutation in several solvents have been investigated using Monte Carlo simulation (MCS) of statistical perturbation theory (SPT). In comparing the relative free energies for interconversion of one ion pair, Rb+ to K+, in H2O (TIP4P) in this study with the relative free energies of the computer simulations and the experimental, we found that the figure in this study is -5.00 ± 0.11 kcal/mol. There is good agreement among various studies, taking into account both methods used to obtain the hydration free energies and standard deviations. There is also good agreement between the calculated structural properties of this study and the simulations, ab initio and the experimental results. We have explained the deviation of the relationship between the free energy difference and the Onsager dielectric function of solvents by the electron pair donor properties of the solvents. For the Rb+ and K+ ion pair, the Onsager dielectric function of solvents (or solvent permittivity), donor number of solvent and the differences in solvation dominate the differences in the relative free energies of solvation and partition coefficients

  8. Sexually dimorphic effects of the Lhx7 null mutation on forebrain cholinergic function.

    Fragkouli, A; Stamatakis, A; Zographos, E; Pachnis, V; Stylianopoulou, F

    2006-01-01

    It has been reported recently that mice lacking both alleles of the LIM-homeobox gene Lhx7, display dramatically reduced number of forebrain cholinergic neurons. In the present study, we investigated whether the Lhx7 mutation affects male and female mice differently, given the fact that gender differences are consistently observed in forebrain cholinergic function. Our results show that in adult male as well as female Lhx7 homozygous mutants there is a dramatic loss of choline acetyltransferase immunoreactive forebrain neurons, both projection and interneurons. The reduction of forebrain choline acetyltransferase immunoreactive neurons in Lhx7 homozygous mutants is accompanied by a decrease of acetylcholinesterase histochemical staining in all forebrain cholinergic neuron target areas of both male and female homozygous mutants. Furthermore, there was an increase of M1-, but not M2-, muscarinic acetylcholine receptor binding site density in the somatosensory cortex and basal ganglia of only the female homozygous mutant mice. Such an increase can be regarded as a mechanism acting to compensate for the dramatically reduced cholinergic input, raising the possibility that the forebrain cholinergic system in female mice may be more plastic and responsive to situations of limited neurotransmitter availability. Finally, our study provides additional data for the sexual dimorphism of the forebrain cholinergic system, as female mice appear to have a lower density of M1-muscarinic acetylcholine receptors in the striatal areas of the basal ganglia and a higher density of M2-muscarinic acetylcholine receptors, in a number of cortical areas, as well as the striatal areas of the basal ganglia. PMID:16338089

  9. A BAC transgenic mouse model reveals neuron subtype-specific effects of a Generalized Epilepsy with Febrile Seizures Plus (GEFS+) mutation

    Tang, Bin; Dutt, Karoni; Papale, Ligia; Rusconi, Raffaella; Shankar, Anupama; Hunter, Jessica; Tufik, Sergio; Yu, Frank H.; Catterall, William A; Mantegazza, Massimo; Goldin, Alan L.; Escayg, Andrew

    2009-01-01

    Mutations in the voltage-gated sodium channel SCN1A are responsible for a number of seizure disorders including Generalized Epilepsy with Febrile Seizures Plus (GEFS+) and Severe Myoclonic Epilepsy of Infancy (SMEI). To determine the effects of SCN1A mutations on channel function in vivo, we generated a bacterial artificial chromosome (BAC) transgenic mouse model that expresses the human SCN1A GEFS+ mutation, R1648H. Mice with the R1648H mutation exhibit a more severe response to the proconvu...

  10. The effect of additives on properties, performance and emission of biodiesel fuelled compression ignition engine

    Highlights: • Fuel additives significantly improve the quality of biodiesel and its blends. • Fuel additives used to enhance biodiesel properties. • Fuel saving from optimized vehicle performance and economy with the use of additives. • Emission reduction from fuel system cleanliness and combustion optimization. - Abstract: With growing concern over greenhouse gases there is increasing emphasis on reducing CO2 emissions. Despite engine efficiency improvements plus increased dieselization of the fleet, increasing vehicle numbers results in increasing CO2 emissions. To reserve this trend the fuel source must be changed to renewable fuels which are CO2 neutral. As a renewable, sustainable and alternative fuel for compression ignition engines, biodiesel is widely accepted as comparable fuel to diesel in diesel engines. This is due to several factors like decreasing the dependence on imported petroleum, reducing global warming, increasing lubricity, and reducing substantially the exhaust emissions from diesel engine. However, there is a major disadvantage in the use of biodiesel as it has lower heating value, higher density and higher viscosity, higher fuel consumption and higher NOX emission, which limits its application. Here fuel additives become essential and indispensable tools not only to minimize these drawbacks but also generate specified products to meet the regional and international standards. Fuel additives can contribute towards fuel economy and emission reduction either directly or indirectly. Their use enable vehicle performance to be maintained at, or near, optimum over the lifetime of the vehicle. A variety of additives are used in automotive biodiesel fuel to meet specification limits and to enhance quality. For example, metal based additives, oxygenated additives, antioxidants, cetane number improvers, lubricity improvers and cold flow improvers are used to meet specifications and quality. This article is a literature review of the effect of

  11. Biochar mitigates negative effects of salt additions on two herbaceous plant species.

    Thomas, Sean C; Frye, Susan; Gale, Nigel; Garmon, Matthew; Launchbury, Rebecca; Machado, Natasha; Melamed, Sarah; Murray, Jessica; Petroff, Alexandre; Winsborough, Carolyn

    2013-11-15

    Addition of pyrolyzed biomass ("biochar") to soils has commonly been shown to increase crop yields and alleviate plant stresses associated with drought and exposure to toxic materials. Here we investigate the ability of biochar (at two dosages: 5 and 50 t ha(-1)) to mitigate salt-induced stress, simulating road salt additions in a factorial glasshouse experiment involving the broadleaved herbaceous plants Abutilon theophrasti and Prunella vulgaris. Salt additions of 30 g m(-2) NaCl to unamended soils resulted in high mortality rates for both species. Biochar (Fagus grandifolia sawdust pyrolyzed at 378 °C), when applied at 50 t ha(-1) as a top dressing, completely alleviated salt-induced mortality in A. theophrasti and prolonged survival of P. vulgaris. Surviving A. theophrasti plants that received both 50 t ha(-1) biochar and salt addition treatments showed growth rates and physiological performance similar to plants without salt addition. Biochar treatments alone also substantially increased biomass of P. vulgaris, with a ∼50% increase relative to untreated controls at both biochar dosages. Biochar did not significantly affect photosynthetic carbon gain (Amax), water use efficiency, or chlorophyll fluorescence (Fv/Fm) in either species. Our results indicate that biochar can ameliorate salt stress effects on plants through salt sorption, suggesting novel applications of biochar to mitigate effects of salinization in agricultural, urban, and contaminated soils. PMID:23796889

  12. Bioremediation of Diesel Fuel Contaminated Soil: Effect of Non Ionic Surfactants and Selected Bacteria Addition

    Aim of this work was to evaluate influence of two commercial surfactants and inoculum of selected bacteria on biodegradation of diesel fuel in different systems. Among alkyl polyethossilates (Brij family) and sorbitan derivates (Tween family) a first selection of surfactants was performed by estimation of Koc and Dafnia magna EC50 with molecular descriptor and QSAR model. Further experiments were conducted to evaluate soil sorption, biodegradability and toxicity. In the second part of the research, the effect of Brij 56, Tween 80 and selected bacteria addition on biodegradation of diesel fuel was studied in liquid cultures and in slurry and solid phase systems. The latter experiments were performed with diesel contaminated soil in bench scale slurry phase bioreactor and solid phase columns. Tween 80 addition increased the biodegradation rate of hydrocarbons both in liquid and in slurry phase systems. Regarding the effect of inoculum, no enhancement of biodegradation rate was observed neither in surfactant added nor in experiments without addition. On the contrary, in solid phase experiments, inoculum addition resulted in enhanced biodegradation compared to surfactant addition

  13. Effect of phosphorus addition in combustion of biomass fuels; Effekter av fosfortillsats vid foerbraenning av biomassa

    Grimm, Alejandro; Skoglund, Nils; Eriksson, Gunnar; Bostroem, Dan; Oehman, Marcus

    2010-11-15

    The results from this project show that phosphorous-rich additives could be of interest to reduce fouling and high temperature corrosion without causing increase in slagging and/or bed agglomeration tendency for typical biofuels. General results in this series of experiments show that in order to achieve a good potassium-binding effect the calcium and magnesium content should be low in the phosphorous-rich fuel and additive. If the content of Ca and Mg is high in the final fuel mixture (including both P-fuel/additive and the bulk fuel) the K-binding effect is reduced and more P needs to be added. Of course, this also means that the additive of choice (fuel or chemical) should have a low content of calcium and magnesium. It is therefore probable that the best results will be obtained when using a fuel mix where the final blend has a molar ratio of P/(K+Na+2/3Ca+2/3Mg) approaching 1. For instance, using monoammonium phosphate, this would be equivalent to a cost (autumn 2009) of about 9-14, 10-15 and 30-40 SEK in P-additive cost per MWh of added fuel to achieve this molar ratio for typical logging residue, salix and wheat straw biofuels.

  14. Towards understanding the effects of additives on the vermicomposting of sewage sludge.

    Xing, Meiyan; Lv, Baoyi; Zhao, Chunhui; Yang, Jian

    2015-03-01

    This work evaluated the effects of additives on the chemical properties of the final products (vermicompost) from vermicomposting of sewage sludge and the adaptable characteristics of Eisenia fetida during the process. An experimental design with different ratios of sewage sludge and the additives (cattle dung or pig manure) was conducted. The results showed that the vermicomposting reduced total organic carbon and the quotient of total organic carbon to total nitrogen (C/N ratio) of the initial mixtures and enhanced the stability and agronomical value of the final products. Notably, principal component analysis indicated that the additives had significant effects on the characteristics of the vermicomposts. Moreover, the vermibeds containing cattle dung displayed a better earthworm growth and reproduction than those with pig manure. Additionally, redundancy analysis demonstrated that electrical conductivity (EC), pH, and C/N ratio played crucial roles on earthworm growth and reproduction. In all, the additives with high C/N ratio, pH buffering capacity, and low EC are recommended to be used for vermicomposting of sewage sludge. PMID:25328094

  15. Effects of additives in {alpha}- and {theta}-alumina: an ab initio study

    Wallin, Erik; Andersson, Jon M; Chirita, Valeriu; Helmersson, Ulf [Department of Physics, Linkoeping University, SE-581 83 Linkoeping (Sweden)

    2004-12-15

    It is of high fundamental and practical importance to be able to control the formation and stability of the different crystalline phases of alumina (Al{sub 2}O{sub 3}). In this study, we have used density functional theory methods to investigate the changes induced in the thermodynamically stable {alpha} phase and the metastable {theta} phase as one eighth of the Al atoms are substituted for different additives (Sc, W, Mo, Cr, Cu, Si, and B). The calculations predict that the additives strongly affect the relative stability between the two phases. Most tested additives are shown to shift the relative stability towards, and in some cases completely stabilize, the {theta} phase, while Cu doping is predicted to increase the relative stability of the {alpha} phase. The reasons for these effects are discussed, as are possible implications on the growth and use of doped aluminas in practical applications. In addition, the effects of the additives on bulk moduli and densities of states have been investigated.

  16. Effect of three different anti-mycotoxin additives on broiler chickens exposed to aflatoxin B1

    AA Oliveira

    2015-01-01

    Full Text Available The growth of filamentous fungi on food often causes, aside from its deterioration, the mycotoxin production which determines economic losses in poultry industry, such as decreased productivity and injuries on poultry's carcass. Adsorbents based on yeast cell wall from Saccharomyces cerevisiae, which contain esterified glucomannan, are an alternative to reduce the mycotoxins bioavailability. The aim of this study was to compare in vitro and in vivo the performance of new three anti-mycotoxin additives (AMA based on yeast cell wall from Saccharomyces cerevisiae. The adsorption process was quantified in vitro, and the data obtained when plotted with Hill's equation indicated a cooperative process. Then, the three different AMA were tested for its ability to reduce the effects of aflatoxins in the diet of growing broiler chickens. The addition of 1 mg kg-1 aflatoxin B1 to the diets of broilers caused a negative change on the performance parameters besides increasing liver weight, fatty degeneration and liver necrosis. The addition of two different kinds of AMA (0.2% could reverse such effects. In conclusion, AMA 1 and 2 are additives with good potential for application on animal production. The AMA 3 ingredients must be re-tested alone for its adsorption capacity. These are the first data reported from Brazil anti-mycotoxin additives with preliminary isothermal analysis. Since beneficial characteristics of S. cerevisiae cell wall in animal industry are strain dependent, this study suggests two new promising alternatives to ameliorate mycotoxin problem.

  17. Categorical and continuous - disentangling the neural correlates of the carry effect in multi-digit addition

    Dressel Katharina

    2010-11-01

    Full Text Available Abstract Background Recently it was suggested that the carry effect observed in addition involves both categorical and continuous processing characteristics. Methods In the present study, we aimed at identifying the specific neural correlates associated with processing either categorical or continuous aspects of the carry effect in an fMRI study on multi-digit addition. Results In line with our expectations, we observed two distinct parts of the fronto-parietal network subserving numerical cognition to be associated with either one of these two characteristics. On the one hand, the categorical aspect of the carry effect was associated with left-hemispheric language areas and the basal ganglia probably reflecting increased demands on procedural and problem solving processes. Complementarily, the continuous aspect of the carry effect was associated with increased intraparietal activation indicating increasing demands on magnitude processing as well as place-value integration with increasing unit sum. Conclusions In summary, the findings suggest representations and processes underlying the carry effect in multi-digit addition to be more complex and interactive than assumed previously.

  18. In-line image analysis on the effects of additives in batch cooling crystallization

    Qu, Haiyan; Louhi-Kultanen, Marjatta; Kallas, Juha

    2006-03-01

    The effects of two potassium salt additives, ethylene diamine tetra acetic acid dipotassium salt (EDTA) and potassium pyrophosphate (KPY), on the batch cooling crystallization of potassium dihydrogen phosphate (KDP) were investigated. The crystal growth rates of certain crystal faces were determined from in-line images taken with a MTS particle image analysis (PIA) video microscope. An in-line image processing method was developed to characterize the size and shape of the crystals. The nucleation kinetics was studied by measurement of the metastable zone width and induction time. A significant promotion effect on both nucleation and growth of KDP was observed when EDTA was used as an additive. KPY, however, exhibited strong inhibiting impacts. The mechanism underlying the EDTA promotion effect on crystal growth was further studied with the 2-dimension nucleation model. It is shown that the presence of EDTA increased the density of adsorbed molecules of the crystallizing solute on the surface of the crystal.

  19. Effect gamma radiation on stabilized NBR/PVC blend in presence of various additives

    The effect of Gamma Irradiation on the physico-mechanical and electrical properties of acrylonitrile-butadiene rubber(NBR)/polyvinyl chloride(PVC) blend in presence of different additives has been studied. The additives include: stabilizers, fillers and crosslinking co agent. The stabilizer system magnesium oxide/zinc oxide/stearic acid was found to improve all the considered properties over the whole range of irradiation. The incorporation of fillers namely, HAF-carbon black, talc and flespar changed the properties of the blend. The addition of HAF-carbon black resulted in a high improvement in the mechanical and electrical properties of the blend. The improvement due to talc was relatively small and became higher upon the addition of the co agent. In contrast, flespar deteriorates the mechanical properties of the blend which make the addition of co agent is very necessary. The highest improvement was attained at 140 kGy in presence of the co agent. The addition of both talc and flespar slightly improves the electric resistance of the enhanced blend, especially, at low irradiation doses.20 fig

  20. Experimental investigation of effects of bio-additives on fuel economy of the gasoline engine

    2008-01-01

    The matter extracted from palm oil was considered as gasoline additive. The effect of various percentages (0.2%, 0.4% and 0.6%) of the bio-additives on fuel economy of SI engine respectively running on prime gasoline, gasoline with known compo- nents, ethanol gasoline, and methanol gasoline under typical urban operation condition 2000 r/min was investigated. The results showed that the bio-additives can remarkably improve the fuel economy of SI engine while operating on all kinds of fuel. The optimal ratio of bio-additive to gasoline depends on the fuel used and on the different engine operating conditions. Besides, the experiments of constant volume combustion bomb, analysis of in cylinder processes, the synchrotron ra- diation and high-temperature friction were conducted to probe into the mechanism of the bio-additive impact on fuel economy. It indicated that the bio-additives can increase the maximum cylinder combustion pressure, improve exhaust emissions and largely reduce the frication coefficient.

  1. Experimental investigation of effects of bio-additives on fuel economy of the gasoline engine

    YAO ChunDe; ZHANG ZhiHui; XU YuanLi; HUANG Yu

    2008-01-01

    The matter extracted from palm oil was considered as gasoline additive. The effect of various percentages (0.2%, 0.4% and 0.6%) of the bio-additives on fuel economy of SI engine respectively running on prime gasoline, gasoline with known compo-nents, ethanol gasoline, and methanol gasoline under typical urban operation condition 2000 r/min was investigated. The results showed that the bio-additives can remarkably improve the fuel economy of Sl engine while operating on all kinds of fuel. The optimal ratio of bio-additive to gasoline depends on the fuel used and on the different engine operating conditions. Besides, the experiments of constant volume combustion bomb, analysis of in cylinder processes, the synchrotron re-dietion and high-temperature friction were conducted to probe into the mechanism of the bio-additive impact on fuel economy. It indicated that the bio-additives can increase the maximum cylinder combustion pressure, improve exhaust emissions and largely reduce the frication coefficient.

  2. Effect of Ingredient Loading on Surface Migration Kinetics of Additives in Vulcanized Natural Rubber Compounds

    Bryan B. Pajarito

    2014-12-01

    Full Text Available Surface migration kinetics of chemical additives in vulcanized natural rubber compounds were studied as function of ingredient loading. Rubber sheets were compounded according to a 212-8 fractional factorial design of experiment, where ingredients were treated as factors varied at two levels of loading. Amount of migrated additives in surface of rubber sheets was monitored through time at ambient conditions. The maximum amount and estimated rate of additive migration were determined from weight loss kinetic curves. Attenuated total reflection–Fourier transform infrared (ATR-FTIR spectroscopy and optical microscopy were used to characterize the chemical structure and surface morphology of sheet specimens during additive migration. ANOVA results showed that increased loading of reclaimed rubber, CaCO3, and paraffin wax signif icantly decreased the maximum amount of additive migration; by contrast, increased loading of used oil, asphalt, and mercaptobenzothiazole disulphide (MBTS increased the maximum amount. Increased loading of sulfur, diphenylguanidine (DPG, and paraffin wax significantly decreased the additive migration rate; increased loading of used oil, asphalt, and stearic acid elicited an opposite effect. Comparison of ATRFTIR spectra of migrated and cleaned rubber surfaces showed signif icant variation in intensity of specif ic absorbance bands that are also present in infrared spectra of migrating chemicals. Paraffin wax, used oil, stearic acid, MBTS, asphalt, and zinc stearate were identified to bloom and bleed in the rubber sheets. Optical micrographs of migrated rubber surfaces revealed formation of white precipitates due to blooming and of semi-transparent wet patches due to bleeding.

  3. Effect of Dodecylbenzene Sulfonic Acid Used as Additive on Residue Hydrotreating

    Sun Yudong; Yang Chaohe

    2015-01-01

    The effect of additive—dodecylbenzene sulfonic acid (DBSA)—on residue hydrotreating was studied in the au-toclave. The results showed that the additive improved stabilization of the colloid system of residue, which could delay the aggregation and coke formation from asphaltenes on the catalyst, and make heavy components transformed into light oil. The residue conversion in the presence of this additive increased by 1.94%, and the yield of light oil increased by 1.53% when the reaction time was 90 min. The surface properties of the catalyst in the presence of this additive were better than that of the blank test within a very short time (30 min) and deteriorated rapidly after a longer reaction time due to higher conversion and coke deposition. Compared with the blank test, the case using the said additive had shown that the structure of hydrotreated asphaltene units was smaller and the condensation degrees were higher. The test results indicated that the additive could improve the hydrotreating reactivity of residue via permeation and depolymerization, the heavier components could be transformed into light oil more easily, and the light oil yield and residue conversion were higher for the case using the said additive in residue hydrotreating process.

  4. Effects of montmorillonite addition on the performance of starch-based wood adhesive.

    Li, Zhaofeng; Wang, Jian; Li, Caiming; Gu, Zhengbiao; Cheng, Li; Hong, Yan

    2015-01-22

    Effects of montmorillonite (MMT) addition on the performance of corn starch-based wood adhesive were investigated. It was found that MMT addition could enhance the shear strength of the starch-based wood adhesive. The shear strength of the adhesive with 5% (w/w, dry starch basis) MMT reached 10.6 MPa in the dry state, which was almost twice that of the same adhesive without MMT. Addition of 5% MMT also produced an approximately 1.2-fold increase in the shear strength in the wet state. Although this addition caused an increase in the viscosity, the resulting adhesive retained both good mobility and viscosity stability during storage. MMT also enhanced the shear-thinning and solid-like behaviors of the adhesive, compared with the adhesive without MMT. Finally, MMT addition improved the thermal stability of the adhesive. In conclusion, addition of MMT to starch-based wood adhesives can improve their overall performance, enhancing their value as alternatives for traditional petrochemical-based wood adhesives. PMID:25439910

  5. Effects of water and nitrogen addition on species turnover in temperate grasslands in northern China.

    Zhuwen Xu

    Full Text Available Global nitrogen (N deposition and climate change have been identified as two of the most important causes of current plant diversity loss. However, temporal patterns of species turnover underlying diversity changes in response to changing precipitation regimes and atmospheric N deposition have received inadequate attention. We carried out a manipulation experiment in a steppe and an old-field in North China from 2005 to 2009, to test the hypothesis that water addition enhances plant species richness through increase in the rate of species gain and decrease in the rate of species loss, while N addition has opposite effects on species changes. Our results showed that water addition increased the rate of species gain in both the steppe and the old field but decreased the rates of species loss and turnover in the old field. In contrast, N addition increased the rates of species loss and turnover in the steppe but decreased the rate of species gain in the old field. The rate of species change was greater in the old field than in the steppe. Water interacted with N to affect species richness and species turnover, indicating that the impacts of N on semi-arid grasslands were largely mediated by water availability. The temporal stability of communities was negatively correlated with rates of species loss and turnover, suggesting that water addition might enhance, but N addition would reduce the compositional stability of grasslands. Experimental results support our initial hypothesis and demonstrate that water and N availabilities differed in the effects on rate of species change in the temperate grasslands, and these effects also depend on grassland types and/or land-use history. Species gain and loss together contribute to the dynamic change of species richness in semi-arid grasslands under future climate change.

  6. Assessment of the Low Alloy Cast Steel Inoculation Effects with Chosen Additives

    D. Bartocha

    2012-04-01

    Full Text Available Structure, and thus the mechanical properties of steel are primarily a function of chemical composition and the solidification process which can be influenced by the application of the inoculation treatment. This effect depends on the modifier used. The article presents the results of studies designed to assess the effects of structural low alloy steel inoculation by selected modifying additives. The study was performed on nine casts modeled with different inoculants, assessment of the procedure impact was based on the macrostructure of made castings. The ratio of surface area equivalent to the axial zone of the crystals and columnar crystals zone was adopted as a measure of the inoculation effect.

  7. Regional and ethnic distribution of beta thalassemia mutations and effect of consanguinity in patients referred for prenatal diagnosis

    To determine the regional and ethnic distribution of beta thalassemia mutation and the effect of consanguinity in patients referred for prenatal diagnosis of beta b-thalassemia and to target the high risk population for screening. A total of 499 couples were referred to Gentec Lab., Lahore, from all over Pakistan for prenatal diagnosis of b-thalassemia. After counseling, chorionic villus sampling was done between 10-16 weeks of gestation. DNA analysis was done by Amplification Refractory Mutation System (ARMS) for type of mutation in the Armed Forces Institute of Pathology, Rawalpindi. Ethnicity, race and consanguineous relationship of parents was determined.b-thalassemia was prevalent in Punjabis (60.7%) followed by Saraikees (25.5%). Castewise it was most frequent in Rajputs followed by Jatts, Arain, Sheikhs and Pathans. 56.7% of the couples were first cousins and 19.8% were relatives. The commonest mutations were Frameshift 8-9 (Fr8-9) 33.5%, Intervening Sequence 1-5 (IVS 1-5) 17.2%, Fr4142 - 8%, IVS 1-1 - 5.2%, Deletion 619 (Del 619) 4.2% and Codon 5 (Cd 5) - 4.2%. In samples sent for analysis, 53.1% turned out to be carriers (trait), 25.3% were diseased (thalassemia major) and 21.6% were normal. P-value of all results was less than 0.001. In this series, the highest frequency was found in Punjabi Rajputs. The commonest mutation was Fr 8-9. Most parents were first cousins. Premarital thalassemia carrier testing can effectively reduce the disease. (author)

  8. Antimutagenic effect of Phellinus rimosus (Berk) Pilat against chemical induced mutations of histidine dependent Salmonella typhimurium strains.

    Ajith, T A; Janardhanan, K K

    2011-10-01

    Mutations are one of the important factors contributing to oncogenesis. Somatic mutations have been detected in oncogenes and tumor suppressor genes in various types of cancers. In vitro antimutagenic activity of ethyl acetate extract of macro fungus, Phellinus rimosus was evaluated by Ames' mutagenicity assay. The effect was evaluated against the direct acting mutagens (sodium azide, N-methyl-N'-nitro-N-nitrosoguanidine, doxorubicin and 4-nitro-o-phenylenediamine) and mutagen needing activation (2-acetyl aminofluorine, and benzo[a]pyrene). The extract was significantly (p<0.05) and dose dependently effective against direct acting mutagens and mutagen needing activation. Among the antimutagenic activity against directly acting mutagens, effect was found to be highest against doxorubicin-induced mutation. The antimutagenic effect of the extract against indirect acting mutagen in the presence of mammalian metabolic activation system was also found to be significant (p<0.01). The background bacterial growth and number of revertant colonies in the extract alone treated plate with or with out metabolic activator was almost same as that of spontaneous revertants. This indicated the non-toxic nature of the extract. The effect was partially ascribed to the antioxidant activity. The results of the study suggest the possible antitumor mechanisms of P. rimosus. PMID:21784121

  9. Effect of cerium addition on microstructures of carbon-alloyed iron aluminides

    S Sriram; R Balasubramaniam; M N Mungole; S Bharagava; R G Baligidad

    2005-10-01

    The effect of Ce addition on the microstructure of carbon-alloyed Fe3Al-based intermetallic has been studied. Three different alloys of composition, Fe–18.5Al–3.6C, Fe–20.0Al–2.0C and Fe–19.2Al–3.3C–0.07Ce (in at%), were prepared by electroslag remelting process. Their microstructures were characterized using optical and scanning electron microscopies. Stereological methods were utilized to understand the observed microstructures. All the alloys exhibited a typical two-phase microstructure consisting of Fe3AlC carbides in an iron aluminide matrix. In the alloy without Ce addition, large bulky carbides were equally distributed throughout the matrix with many smaller precipitates interspersed in between. In the alloy with Ce addition, the carbide grain sizes were finer and uniformly distributed throughout the matrix. The effect of Ce addition on the carbide morphology has been explained based on the known effect of Ce in modifying carbide morphology in cast irons.

  10. Effects of Ce additions on the age hardening response of Mg–Zn alloys

    The effects of Ce additions on the precipitation hardening behaviour of Mg–Zn are examined for a series of alloys, with Ce additions at both alloying and microalloying levels. The alloys are artificially aged, and studied using hardness measurement and X-ray diffraction, as well as optical and transmission electron microscopy. It is found that the age-hardening effect is driven by the formation of fine precipitates, the number density of which is related to the Zn content of the alloy. Conversely, the Ce content is found to slightly reduce hardening. When the alloy content of Ce is high, large secondary phase particles containing both Ce and Zn are present, and remain stable during solutionizing. These particles effectively reduce the amount of Zn available as solute for precipitation, and thereby reduce hardening. Combining hardness results with thermodynamic analysis of alloy solute levels also suggests that Ce can have a negative effect on hardening when present as solutes at the onset of ageing. This effect is confirmed by designing a pre-ageing heat treatment to preferentially remove Ce solutes, which is found to restore the hardening capability of an Mg–Zn–Ce alloy to the level of the Ce-free alloy. - Highlights: • The effects of Ce additions on precipitation in Mg–Zn alloys are examined. • Additions of Ce to Mg–Zn slightly reduce the age-hardening response. • Ce-rich secondary phase particles deplete the matrix of Zn solute. • Hardening is also decreased when Ce is present in solution. • Pre-ageing to preferentially precipitate out Ce restores hardening capabilities

  11. EFFECT OF METALLOID COMPOUND AND BIO-SOLUTION ADDITIVES ON BIODIESEL ENGINE PERFORMANCE AND EXHAUST EMISSIONS

    Karoon Fangsuwannarak; Kittichai Triratanasirichai

    2013-01-01

    The purpose of this study is to perform comparative analysis of the effect of the different fuel additives as polymer based-bio-solution, natural organic based-bio-solution and nano-titanium metalloid (TiO2) compound on the performance parameters and exhuast emissions of a pickup Diesel engine, operating on commercial Diesel fuel (D) and B5 palm biodiesel (95% D+5% palm oil). The basic properties of the fuel blended with TiO2 metalloid compound and bio-solution based additives were measured a...

  12. Effect of additional speed endurance training on performance and muscle adaptations

    Gunnarsson, Thomas; Christensen, Peter Møller; Holse, Kris;

    2012-01-01

    PURPOSE: The present study examined the effect of additional speed-endurance training during the season on muscle adaptations and performance of trained soccer players. METHODS: Eighteen sub-elite soccer players performed one session with 6-9 30-s intervals at an intensity of 90-95 % ofmaximal...... intensity (speed endurance training; SET) a week for 5 weeks (SET-intervention). Before and after the SET-intervention the players carried out the Yo-Yo intermittent recovery level 2 (Yo- Yo IR2) test, a sprint test (10- and 30-m) and an agility test. In addition, seven of the players had a resting muscle...

  13. Solvent additive effects on small molecule crystallization in bulk heterojunction solar cells probed during spin casting

    Pérez, Louis A.

    2013-09-04

    Solvent additive processing can lead to drastic improvements in the power conversion efficiency (PCE) in solution processable small molecule (SPSM) bulk heterojunction solar cells. In situ grazing incidence wide-angle X-ray scattering is used to investigate the kinetics of crystallite formation during and shortly after spin casting. The additive is shown to have a complex effect on structural evolution invoking polymorphism and enhanced crystalline quality of the donor SPSM. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  14. The effect of Y2O3 addition on thermal shock behavior of magnesium aluminate spinel

    Pošarac Milica

    2009-01-01

    Full Text Available The effect of yttria additive on the thermal shock behavior of magnesium aluminate spinel has been investigated. As a starting material we used spinel (MgAl2O4 obtained by the modified glycine nitrate procedure (MGNP. Sintered products were characterized in terms of phase analysis, densities, thermal shock, monitoring the damaged surface area in the refractory specimen during thermal shock and ultrasonic determination of the Dynamic Young modulus of elasticity. It was found that a new phase between yttria and alumina is formed, which improved thermal shock properties of the spinel refractories. Also densification of samples is enhanced by yttria addition.

  15. Magnetic Force Microscopy Study of Zr2Co11-Based Nanocrystalline Materials: Effect of Mo Addition

    Lanping Yue; Yunlong Jin; Wenyong Zhang; Sellmyer, David J.

    2015-01-01

    The addition of Molybdenum was used to modify the nanostructure and enhance coercivity of rare-earth-free Zr2Co11-based nanocrystalline permanent magnets. The effect of Mo addition on magnetic domain structures of melt spun nanocrystalline Zr16Co84-xMox (x=0, 0.5, 1, 1.5, and 2.0) ribbons has been investigated. It was found that magnetic properties and local domain structures are strongly influenced by Mo doping. The coercivity of the samples increases with the increase in Mo content (x≤1.5)....

  16. Effect of Yttrium Addition on Glass Forming Ability of ZrCuAlSi Alloy

    The effect of yttrium addition on glass formation of a ZrCuAlSi alloy is investigated. The maximum diameter 8mm of the glassy rods for (Zr46.3Cu43.3Al8.9Si1.5)100−xYx alloy with x = 2.5 is obtained by copper mould casting. Apparent enhancement of the glass formation ability is found with addition of yttrium, mainly due to the purification of the alloy melt and the suppression of formation of the primary phases by yttrium. (condensed matter: structure, mechanical and thermal properties)

  17. Effects of mutated replicase and movement protein genes on attenuation of tobacco mosaic virus

    杨恭; 邱并生; 魏军亚; 刘广超

    2001-01-01

    Our previous reports showed that one opal mutation (UGA) and one ochre mutation (UAA) respectively located in the replicase and movement protein (MP) genes of the attenuated tomato mosaic virus K(ToMV-K) contribute to the viral attenuation. To explore a wider application of this attenuation pattern to other plant viruses, we have constructed three mutants which respectively contain one opal mutation of the replicase gene and/or one ochre mutation of the MP using PCR-mediated site-directed mutagenesis from a virulent tobacco mosaic virus isolated from China (TMV-Cv). Plant infection performed by in vitro transcripts revealed that the MP truncated mutant TMV-Cvmp and the replicase-MP truncated mutant TMV-Cvrase-mp were infectious on both local lesion (Nicotiana tabacum cv. Xanthi NC) and systemic (N. tabacum cv. K326) host plants, while the replicase truncated mutant TMV-Cvrase was non-infectious. The K326 plant infected by TMV- Cvrease-mp displayed only a little mild mosaic. By electronic microscopy (EM), plant re-inoculation, RNA Dot-blot, RT-PCR and sequencing we demonstrated that the progeny viruses of TMV-Cvmp and TMV-Cvrease-mp shared similar morphological character with TMV-Cv, owned the abilities to infect, replicate and propagate in the assayed plants, and maintained the mutated sites during infection. These data showed that both the opal and the ochre mutations are able to cooperatively induce the attenuated phenotypes of TMV-Cvrase-mp on plants, indicating that the mutation pattern of ToMV-K could be used to attenuate other virulent plant viruses.

  18. The effect of oxygen and nitrogen additives on the growth of nanocrystalline diamond films

    Nanocrystalline diamond (NCD) films have been synthesized by using either nitrogen addition or oxygen addition to conventional CH4/H2 mixtures besides the most commonly used Ar/CH4 with or without H2 chemistry. However, the synthesis of NCD films using both nitrogen and oxygen addition simultaneously into CH4/H2 gases has not been reported thus far. In this work, we investigate the effect of simultaneous O2 and N2 addition to CH4/H2 plasma on the growth of nanocrystalline diamond (NCD) films, focusing particularly on the ratio between the amount of O2 and N2 additives into conventional CH4/H2 gas mixtures on the morphology, microstructure, texture, and crystalline quality of the NCD films. The NCD samples were produced by using a high microwave power (3 kW) in a microwave plasma-assisted chemical vapour deposition reactor with a maximum power of 5 kW on large silicon wafers, 2 inches in diameter, and characterized by high-resolution scanning electron microscopy, x-ray diffraction and micro-Raman spectroscopy. Our work demonstrates that, under the conditions investigated here, NCD films can be formed when the ratio of O2/N2 addition is increased from 0 through 1 up to 7/3 (at higher than 7/3, for example 4, a large-grained polycrystalline diamond film will form), and the crystalline quality is significantly enhanced with the increase of oxygen addition. The mechanism of O2 and N2 additives on the formation of NCD films is briefly studied

  19. Absence of Maternal Methylation in Biparental Hydatidiform Moles from Women with NLRP7 Maternal-Effect Mutations Reveals Widespread Placenta-Specific Imprinting

    Sanchez-Delgado, Marta; Martin-Trujillo, Alejandro; Tayama, Chiharu; Vidal, Enrique; Esteller, Manel; Iglesias-Platas, Isabel; Deo, Nandita; Barney, Olivia; Maclean, Ken; Hata, Kenichiro; Nakabayashi, Kazuhiko; Fisher, Rosemary; Monk, David

    2015-01-01

    Familial recurrent hydatidiform mole (RHM) is a maternal-effect autosomal recessive disorder usually associated with mutations of the NLRP7 gene. It is characterized by HM with excessive trophoblastic proliferation, which mimics the appearance of androgenetic molar conceptuses despite their diploid biparental constitution. It has been proposed that the phenotypes of both types of mole are associated with aberrant genomic imprinting. However no systematic analyses for imprinting defects have been reported. Here, we present the genome-wide methylation profiles of both spontaneous androgenetic and biparental NLRP7 defective molar tissues. We observe total paternalization of all ubiquitous and placenta-specific differentially methylated regions (DMRs) in four androgenetic moles; namely gain of methylation at paternally methylated loci and absence of methylation at maternally methylated regions. The methylation defects observed in five RHM biopsies from NLRP7 defective patients are restricted to lack-of-methylation at maternal DMRs. Surprisingly RHMs from two sisters with the same missense mutations, as well as consecutive RHMs from one affected female show subtle allelic methylation differences, suggesting inter-RHM variation. These epigenotypes are consistent with NLRP7 being a maternal-effect gene and involved in imprint acquisition in the oocyte. In addition, bioinformatic screening of the resulting methylation datasets identified over sixty loci with methylation profiles consistent with imprinting in the placenta, of which we confirm 22 as novel maternally methylated loci. These observations strongly suggest that the molar phenotypes are due to defective placenta-specific imprinting and over-expression of paternally expressed transcripts, highlighting that maternal-effect mutations of NLRP7 are associated with the most severe form of multi-locus imprinting defects in humans. PMID:26544189

  20. Trends in lignin modification: a comprehensive analysis of the effects of genetic manipulations/mutations on lignification and vascular integrity

    Anterola, Aldwin M.; Lewis, Norman G.

    2002-01-01

    activities. Such enzymes thus fulfill subsidiary processing roles, with all (except CCOMT) apparently being bifunctional for both H and G substrates. Their severe downregulation does, however, predictably result in impaired monolignol biosynthesis, reduced lignin deposition/vascular integrity, (upstream) metabolite build-up and/or shunt pathway metabolism. There was no evidence for an alternative acid/ester O-methyltransferase (AEOMT) being involved in lignin biosynthesis.The G/S lignin pathway networks are operative in specific cell types in angiosperms and employ two additional biosynthetic steps to afford the corresponding S components, i.e. through introduction of an hydroxyl group at C-5 and its subsequent O-methylation. [These enzymes were originally classified as ferulate-5-hydroxylase (F5H) and caffeate O-methyltransferase (COMT), respectively.] As before, neither step has apparently any role in carbon allocation to the pathway; hence their individual downregulation/manipulation, respectively, gives either a G enriched lignin or formation of the well-known S-deficient bm3 "lignin" mutant, with cell walls of impaired vascular integrity. In the latter case, COMT downregulation/mutation apparently results in utilization of the isoelectronic 5-hydroxyconiferyl alcohol species albeit in an unsuccessful attempt to form G-S lignin proper. However, there is apparently no effect on overall G content, thereby indicating that deposition of both G and S moieties in the G/S lignin forming cells are kept spatially, and presumably temporally, fully separate. Downregulation/mutation of further downstream steps in the G/S network [i.e. utilizing 4CL, CCR and CAD isoforms] gives predictable effects in terms of their subsidiary processing roles: while severe downregulation of 4CL gave phenotypes with impaired vascular integrity due to reduced monolignol supply, there was no evidence in support of increased growth and/or enhanced cellulose biosynthesis. CCR and CAD downregulation/mutations

  1. Mutational robustness of gene regulatory networks.

    Aalt D J van Dijk

    Full Text Available Mutational robustness of gene regulatory networks refers to their ability to generate constant biological output upon mutations that change network structure. Such networks contain regulatory interactions (transcription factor-target gene interactions but often also protein-protein interactions between transcription factors. Using computational modeling, we study factors that influence robustness and we infer several network properties governing it. These include the type of mutation, i.e. whether a regulatory interaction or a protein-protein interaction is mutated, and in the case of mutation of a regulatory interaction, the sign of the interaction (activating vs. repressive. In addition, we analyze the effect of combinations of mutations and we compare networks containing monomeric with those containing dimeric transcription factors. Our results are consistent with available data on biological networks, for example based on evolutionary conservation of network features. As a novel and remarkable property, we predict that networks are more robust against mutations in monomer than in dimer transcription factors, a prediction for which analysis of conservation of DNA binding residues in monomeric vs. dimeric transcription factors provides indirect evidence.

  2. Classification of suppressor additives based on synergistic and antagonistic ensemble effects

    Highlights: → Three fundamental types of suppressor additives for copper electroplating could be identified by means of potential transient measurements. → These suppressor additives differ in their synergistic and antagonistic interplay with anions that are chemisorbed on the metallic copper surface during electrodeposition. → In addition these suppressor chemistries reveal different barrier properties with respect to cupric ions and plating additives (Cl, SPS). - Abstract: Three fundamental types of suppressor additives for copper electroplating could be identified by means of potential transient measurements. These suppressor additives differ in their synergistic and antagonistic interplay with anions that are chemisorbed on the metallic copper surface during electrodeposition. In addition these suppressor chemistries reveal different barrier properties with respect to cupric ions and plating additives (Cl, SPS). While the type-I suppressor selectively forms efficient barriers for copper inter-diffusion on chloride-terminated electrode surfaces we identified a type-II suppressor that interacts non-selectively with any kind of anions chemisorbed on copper (chloride, sulfate, sulfonate). Type-I suppressors are vital for the superconformal copper growth mode in Damascene processing and show an antagonistic interaction with SPS (Bis-Sodium-Sulfopropyl-Disulfide) which involves the deactivation of this suppressor chemistry. This suppressor deactivation is rationalized in terms of compositional changes in the layer of the chemisorbed anions due to the competition of chloride and MPS (Mercaptopropane Sulfonic Acid) for adsorption sites on the metallic copper surface. MPS is the product of the dissociative SPS adsorption within the preexisting chloride matrix on the copper surface. The non-selectivity in the adsorption behavior of the type-II suppressor is rationalized in terms of anion/cation pairing effects of the poly-cationic suppressor and the anion

  3. Effects of lipids on thermophilic anaerobic digestion and reduction of lipid inhibition upon addition of bentonite.

    Angelidaki, I; Petersen, S P; Ahring, B K

    1990-07-01

    The effect of bentonite-bound oil on thermophilic anaerobic digestion of cattle manure was investigated. In digestor experiments, addition of oil was found to be inhibitory during start-up and the inhibitory effect was less pronounced when the oil was added in the form of bentonite-bound oil compared to when the oil was added alone. After adaptation of the digestors, very rapid degradation of oil was observed and more than 80% of the oil was degraded within a few hours after daily feeding. In batch experiments, glyceride trioleate was found to be inhibitory to thermophilic anaerobic digestion when the concentrations were higher than 2.0 g/l. However, addition of bentonite (a clay mineral) at concentrations of 0.15% and 0.45% was found to partly overcome this inhibition. Addition of calcium chloride in concentration of 3 mM (0.033% w/v) showed a similar positive effect on the utilization of oil, but the effect was lower than with bentonite. PMID:1366749

  4. Effects of brine addition on effluent toxicity and marine toxicity identification evaluation (TIE) manipulations

    Ho, K.T.; Burgess, R.M. (Environmental Protection Agency, Narragansett, RI (United States)); Mitchell, K. (Xavier Univ. of Louisiana, New Orleans, LA (United States). Biology Dept.); Zappala, M. (Univ. of Rhode Island, Kingston, RI (United States))

    1995-02-01

    Little information is available concerning the effect of salinity adjustment on effluent storage and toxicity identification evaluation (TIE) performance. These factors are important for accurate assessments of potential toxicity to marine organisms. The objective of this study was to determine (a) the effect of salinity adjustment using hypersaline brine on the toxicity of effluents stored up to 40 d, and (b) to determine the effect of salinity adjustment on TIE manipulations. Changes in effluent toxicity over time were examined by using a municipal and an industrial effluent. A toxicity time series was performed for 16 d for the industrial effluent and 40 d for the municipal effluent. Toxicity was measured with modified 48-h acute Mysidopsis bahia and Menidia beryllina tests. Results indicate that, compared to day 0 test results, effluent stored with brine had fewer significant changes in toxicity than did effluent stored without brine. To determine the effects of brine addition on TIE manipulations, the authors conducted a series of manipulations in which one aliquot of an effluent had brine added prior to the TIE manipulations and the other aliquot had brine added after the TIE manipulation. The manipulations conducted were EDTA addition, sodium thiosulfate addition, C[sub 18] extraction, aeration, filtration, and graduated pH manipulations. Toxicity was measured with the modified 48-h acute mysid test. Addition of brine had no effect on the outcome of TIE manipulations. They have concluded that it is operationally easier to add brine as soon as possible after sampling and that effluent tests should be conducted as soon as practical.

  5. Effect of basic additives on sensitivity and diffusion of acid in chemical amplification resists

    Asakawa, Koji; Ushirogouchi, Tohru; Nakase, Makoto

    1995-06-01

    The effect of amine additives in chemical amplification resists is discussed. Phenolic amines such as 4-aminophenol and 2-(4-aminophenyl)-2-(4-hydroxyphenyl) propane were investigated as model compounds from the viewpoint of sensitivity, diffusion and resolution. Equal molar amounts of acid and amine deactivated at the very beginning of post-exposure bake, and could not participate in decomposing the inhibitor as a catalyst. Only the acid which survived from the deactivation diffuses in the resist, decomposing the inhibitors from the middle to late stage of PEB. The basic additives reduce the diffusion range of the acid, especially for long-range diffusion, resulting in higher contrast at the interfaces between the exposed and unexposed areas. In addition, the amine concentration required is found to be less than the concentration which causes the resist sensitivity to start decreasing.

  6. Effect of bauxite addition on densification and mullitization behaviour of West Bengal clay

    N S Raut; P Biswas; T K Bhattacharya; K Das

    2008-12-01

    The effect of bauxite addition on the densification and mullitization of reaction sintered bauxite–clay mixture had been studied in the temperature range 1400–1500°C. The maximum bulk density (2.89 g/cc) and minimum apparent porosity (0.58%) was achieved by addition of 50 wt% bauxite. The impurities present in bauxite and clay formed liquid phase which helped in particle diffusion to aid densification. The X-ray diffraction of sample fired at 1500°C showed cristoballite phase gradually disappearing and at the same time mullite and -Al2O3 phase appearing at a higher level of bauxite addition. The in situ nascent alumina formed was reactive that facilitated the formation of secondary mullite by solution precipitation mechanism. The presence of bauxite also changed the morphology of the mullite particles. Two types of mullite were distinctly observed in the SEM photographs: elongated primary mullite and equiaxed secondary mullite.

  7. Effect of Ca addition on the corrosion behavior of Mg-Al-Mn alloy

    Yang, Jiang; Peng, Jian; Nyberg, Eric A.; Pan, Fu-sheng

    2016-04-01

    The microstructures and corrosion resistance of magnesium-5 wt% aluminum-0.3 wt% manganese alloys (Mg-Al-Mn) with different Ca additions (0.2-4 wt%) were investigated. Results showed that with increasing Ca addition, the grain of the alloys became more refined, whereas the corrosion resistant ability of the alloys initially increased and then decreased. The alloy with 2 wt% Ca addition exhibited the best corrosion resistance, attributed to the effect of the oxide film and (Mg,Al)2Ca phases which were discontinuously distributed on the grain boundaries. These phases acted as micro-victims, they preferentially corroded to protect the α-Mg matrix. The oxide film formed on the alloy surface can hinder the solution further to protect the α-Mg matrix.

  8. Effect of argon addition on plasma parameters and dust charging in hydrogen plasma

    Experimental results on effect of adding argon gas to hydrogen plasma in a multi-cusp dusty plasma device are reported. Addition of argon modifies plasma density, electron temperature, degree of hydrogen dissociation, dust current as well as dust charge. From the dust charging profile, it is observed that the dust current and dust charge decrease significantly up to 40% addition of argon flow rate in hydrogen plasma. But beyond 40% of argon flow rate, the changes in dust current and dust charge are insignificant. Results show that the addition of argon to hydrogen plasma in a dusty plasma device can be used as a tool to control the dust charging in a low pressure dusty plasma.

  9. Effect of Yb additions on microstructures and properties of 7A60 aluminum alloy

    FANG Hua-chan; CHEN Kang-hua; ZHANG Zhuo; ZHU Chang-jun

    2008-01-01

    Al-Zn-Mg-Cu-Zr alloys containing Yb were prepared by cast metallurgy. Effect of 0.30% Yb additions on the microstructure and properties of 7A60 aluminum alloys with T6 and T77 aging treatments was investigated by TEM, optical microscopy, hardness and electric conductivity measurement, tensile test and stress corrosion cracking test. The results show that the Yb additions to high strength Al-Zn-Mg-Cu-Zr aluminum alloys can produce fine coherent dispersoids. Those dispersoids can strongly pin dislocation and subgrain boundaries, which can significantly retard the recrystallization by inhibiting the nucleation of recrystallization and the growth of subgrains and keeping low-angle subgrain boundaries. Yb additions can obviously enhance the resistance to stress corrosion cracking and the fracture toughness property, and mildly increase the strength and ductility with T6 and T77 treatments.

  10. Effects of Ca addition on microstructure and properties of AZ63 magnesium alloy

    钱宝光; 耿浩然; 陶珍东; 赵鹏; 田宪法

    2004-01-01

    Effects of Ca addition on the microstructure and viscosity as well as electrochemical properties of casting AZ63 magnesium alloy were studied. Testing results show that the viscosity value increases with the increase of calcium content, especially at the higher temperature, and there exists such a relation between the ignition temperature and viscosity of magnesium alloy: when the melt viscosity increases, the ignition temperature increases too. The microstructure of AZ63 magnesium alloy is first refined and then coarsened with the increase of Ca addition. By the addition of 0.15% Ca, AZ63 alloy has more negative open-circuit potential(1. 624 5V), bigger anode efficiency (55.65%) and lower corrosion rate(0.214g/(m2·h).AZ63 allo6y containing some Ca content is a high driving-potential and high-efficiency sacrificial anodes material.

  11. Effects of Ni addition on liquid phase separation and giant magnetoresistance of Cu-Co alloys

    2001-01-01

    The effects of Ni addition on the liquid phase separation and giant magnetoresistance (GMR) of Cu-Co alloys were discussed. The results reveal that Ni addition can partially restrain the liquid phase separation of Cu-Co alloys, resulting in a decrease of volume fraction for the Co-rich particles separated from the liquid phase and in refined microstructures. The composition analyses indicate that Ni is dissolved in both the Co-rich and the Cu-rich phases, but Ni content in the Co-rich phase is much higher than that in the Cu matrix. At the same time, Ni addition enhance the solubility between Cu and Co, especially Cu in Co solid solution. Ni alloying into Cu-Co alloys can fully prevent the liquid phase separation during melt spinning, which is very beneficial to improve GMR of Cu-Co alloys.

  12. Effect of Microsilica Addition on the Properties of Mullite-Corundum Ceramic

    2006-01-01

    In this work, the effect of microsilica addition on properties of mullite-corundum ceramic specimens fired at temperatures from 1550℃ to 1700℃ has been investigated. It is found that the temperature at 1650℃is an important turning point for the sintering of mullite-corundum ceramic. When the firing temperature exceeds 1650℃, the mullite phase will decompose,which affects the properties and microstructure of the ceramic. The bulk density of the ceramic decreases with the microsilica addition, but increases with the firing temperature from 1550℃ up to 1700℃. The cold compressive strength of the specimens increases with firing temperature. Thermal shock resistance of the ceramic is strongly dependent on firing temperature, but little on the chosen microsilica addition.

  13. Effect of Carbon Addition on Microstructure and Properties of WC-Co Cemented Carbides

    Chongbin Wei; Xiaoyan Song; Jun Fu; Xiaosen Lv; Haibin Wang; Yang Cao; ShixianZhao; Xuemei Liu

    2012-01-01

    Based on a unique method to synthesize WC-Co composite powder by in-situ reactions of metal oxides and carbon, the effects of the carbon addition in the initial powders on the phase constitution, microstructure and mechanical properties of the cemented carbides were investigated. It is found that with a suitable carbon addition the pure phase constitution can be obtained in the sintered bulk from the composite powder. The mechanical properties of the cemented carbides depend on the phase constitution and the WC grain structure. To obtain the excellent properties of the WC-Co bulk, it is important to obtain the pure phase constitution from the appropriate carbon addition in the initial powders and a suitable grain size.

  14. Effect of Ca and Y additions on oxidation behavior of magnesium alloys at high temperatures

    FAN Jianfeng; YANG Changlin; XU Bingshe

    2012-01-01

    Oxidation and ignition of magnesium alloys at elevated temperature were successfully retarded by additions of Y and Ca.which could be melted at 1173 K in air without any protection.Thermogravimetric measurements in dry air revealed that the oxidation dynamics curves of Mg-2.5Ca alloy and Mg-3.5Y-0.79Ca alloy at high temperatures followed the parabolic-line law or the ubic-line law.X-ray diffraction (XRD) and scanning electron microscopy (SEM) analysis indicated that the oxide film on the surface of Mg-3.5Y-0.79Ca and Mg-2.5Ca alloys exhibited a duplex structure.which agreed with the results of thermodynamic analysis.By comparison,the ignition-proof effect of the combination addition of Y and Ca was better than that of the single addition of Ca.

  15. Dissecting the effect of chemical additives on the enzymatic hydrolysis of pretreated wheat straw.

    Monschein, Mareike; Reisinger, Christoph; Nidetzky, Bernd

    2014-10-01

    Chemical additives were examined for ability to increase the enzymatic hydrolysis of thermo-acidically pretreated wheat straw by Trichoderma reesei cellulase at 50 °C. Semi-empirical descriptors derived from the hydrolysis time courses were applied to compare influence of these additives on lignocellulose bioconversion on a kinetic level, presenting a novel view on their mechanism of action. Focus was on rate retardation during hydrolysis, substrate conversion and enzyme adsorption. PEG 8000 enabled a reduction of enzyme loading by 50% while retaining the same conversion of 67% after 24h. For the first time, a beneficial effect of urea is reported, increasing the final substrate conversion after 48 h by 16%. The cationic surfactant cetyl-trimethylammonium bromide (CTAB) enhanced the hydrolysis rate at extended reaction time (rlim) by 34% and reduced reaction time by 28%. A combination of PEG 8000 and urea increased sugar release more than additives used individually. PMID:25108473

  16. Effect of TiC whisker addition on properties of YG1OF alloy

    2007-01-01

    The cemented carbide material (YG10F) with different additions of TiC whisker (0%, 0.3%, 0.6%, mass fraction) was prepared by different techniques. The effect of TiC whisker addition on the density, microhardness and toughness of the experimental material was investigated. The results indicate that after the wet-milling for 8 h and sintering in vacuum at 1 440 ℃, the toughness of YG10F is remarkably improved and meanwhile higher microhardness is obtained by 0.3% TiC whisker addition. Preliminary analysis suggests that the main toughening mechanism of TiC whisker in YG10F is whisker pull-out and bridging phenomena.

  17. Effect of rhenium addition on tungsten fuzz formation in helium plasmas

    Khan, Aneeqa; De Temmerman, Gregory; Morgan, Thomas W.; Ward, Michael B.

    2016-06-01

    The effect of the addition of rhenium to tungsten on the formation of a nanostructure referred to as 'fuzz' when exposed to helium plasmas at fusion relevant ion fluxes was investigated in the Magnum and Pilot PSI devices at the FOM Institute DIFFER. The effect rhenium had on fuzz growth was seen to be dependent on time, temperature and flux. Initial fuzz growth was seen to be highly dependent on grain orientation, with rhenium having little effect. Once the fuzz was fully developed, the effect of grain orientation disappeared and the rhenium had an inhibiting effect on growth. This could be beneficial for inhibiting fuzz growth in a future fusion reactor, where transmutation of tungsten to rhenium is expected. It also appears that erosion or annealing of the fuzz is limiting growth of fuzz at higher temperatures in the range of ∼1340 °C.

  18. Fisher's geometric model predicts the effects of random mutations when tested in the wild.

    Stearns, Frank W; Fenster, Charles B

    2016-02-01

    Fisher's geometric model of adaptation (FGM) has been the conceptual foundation for studies investigating the genetic basis of adaptation since the onset of the neo Darwinian synthesis. FGM describes adaptation as the movement of a genotype toward a fitness optimum due to beneficial mutations. To date, one prediction of FGM, the probability of improvement is related to the distance from the optimum, has only been tested in microorganisms under laboratory conditions. There is reason to believe that results might differ under natural conditions where more mutations likely affect fitness, and where environmental variance may obscure the expected pattern. We chemically induced mutations into a set of 19 Arabidopsis thaliana accessions from across the native range of A. thaliana and planted them alongside the premutated founder lines in two habitats in the mid-Atlantic region of the United States under field conditions. We show that FGM is able to predict the outcome of a set of random induced mutations on fitness in a set of A. thaliana accessions grown in the wild: mutations are more likely to be beneficial in relatively less fit genotypes. This finding suggests that FGM is an accurate approximation of the process of adaptation under more realistic ecological conditions. PMID:26768168

  19. Effects of p35 Mutations Associated with Mental Retardation on the Cellular Function of p35-CDK5.

    Shunsuke Takada

    Full Text Available p35 is an activation subunit of the cyclin-dependent kinase 5 (CDK5, which is a Ser/Thr kinase that is expressed predominantly in neurons. Disruption of the CDK5 or p35 (CDK5R1 genes induces abnormal neuronal layering in various regions of the mouse brain via impaired neuronal migration, which may be relevant for mental retardation in humans. Accordingly, mutations in the p35 gene were reported in patients with nonsyndromic mental retardation; however, their effect on the biochemical function of p35 has not been examined. Here, we studied the biochemical effect of mutant p35 on its known properties, i.e., stability, CDK5 activation, and cellular localization, using heterologous expression in cultured cells. We also examined the effect of the mutations on axon elongation in cultured primary neurons and migration of newborn neurons in embryonic brains. However, we did not detect any significant differences in the effects of the mutant forms of p35 compared with wild-type p35. Therefore, we conclude that these p35 mutations are unlikely to cause mental retardation.

  20. Effects of Nitrogen and Phosphorus Additions on Carbon Cycling of Tropical Mountain Rainforests in Hainan, China

    Lai, J.

    2015-12-01

    Nitrogen (N) and Phosphorus (P) deposition is projected to increase significantly in tropical regions in the coming decades, which has changed and will change the structure and function of ecosystems, and affects on ecosystem Carbon (C) cycle. As an important part in global C cycle, how the C cycle of tropical rainforests will be influenced by the N and P deposition should be focused on. This study simulated N and P deposition in a primary and secondary forest of tropical mountain rainforest in Jianfengling, Hainan, China, during five-year field experiment to evaluate the effects of N and P deposition on C cycling processes and relate characteristics. Six levels of N and P treatments were treated: Control, Low-N, Medium-N, High-N, P and N+P. The relative growth rates (RGR) of tree layer in treatment plots were different from that in control plots after years of N and P addition. Simulated N and P deposition also increased ANPP in primary forest. N and P addition changed the growth of trees by altering soil nutrient and microbial activities. N and P addition increased soil organic carbon (SOC) and total N (TN) content, and significantly increased soil total P (TP) content, not changing soil pH. During the whole process of N and P addition, as net nitrification rate and net N mineralization rate were promoted by N and P addition, and effective N content (nitrate) of soil increased in the plot treated with N treatments compared to the control treatment. The microbial P content was increased by N and P addition, and microbial N was not changed. The increasing N deposition may enhance soil nutrient and stimulate growth of trees, which will lead to an increase of the C sequestration.

  1. Evidence for a founder effect for the IVS4 +4 A{r_arrow}T mutation in the Fanconi anemia gene FACC in a Jewish population

    Verlander, P.C.; Kaporis, A.G.; Qian, L. [Rockefeller Univ., New York, NY (United States)] [and others

    1994-09-01

    Fanconi anemia (FA) is a genetically heterogeneous autosomal recessive disorder defined by hypersensitivity of cells to DNA cross-linking agents; a gene for complementation group C(FACC) has been cloned. Two common mutations, IVS4 +4 A{r_arrow}T and 322delG, and several rare mutations have recently been reported in affected individuals. We now report the development of amplification refractory mutation system (ARMS) assays for rapid, non-radioactive detection of these known mutations in FACC. Primer pairs specific for variant sequences were designed, with the 3{prime} terminal base of one primer matching the variant base. PCR products are separated by electrophoresis on 2.5% agarose gels; mutations are indicated by the presence of a band of a specific size. These ARMS assays can be multiplexed to allow screening for all known mutations in two PCR reactions. We have used these assays for detection of FACC mutations in affected individuals in the International Fanconi Anemia Registry (IFAR), and for carrier detection FACC families. IVS4 +4 A{r_arrow}T is the only FACC mutation found in Jewish FA patients and their families, of both Ashkenazi and Sephardic ancestry. This mutation was not found in any affected individual of non-Jewish origin. In addition, DNA samples from 1596 healthy Jewish individuals primarily of Ashkenazi ancestry were supplied to us by Dor Yeshorim. These samples, ascertained for carrier screening for Tay Sachs, cystic fibrosis, and other genetic diseases with a high frequency in the religious Jewish community served by this organization, were tested for both IVS4 +4 A{r_arrow}T and 322delG mutations; seventeen IVS4 +4 A{r_arrow}T are of Sephardic Jewish ancestry. We hypothesize that IVS4 +4 A{r_arrow}T is a very old mutation, predating the divergence of the Ashkenazi and Sephardic populations. Haplotype analysis with microsatellite markers is in progress.

  2. Hydrothermal treatment of incineration fly ash for PCDD/Fs decomposition: the effect of iron addition.

    Chen, De-Zhen; Hu, Yu-Yan; Zhang, Peng-Fei

    2012-12-01

    The catalytic effect of Fe addition on the decomposition of polychlorinated dibenzo-dioxins and polychlorinated dibenzofurans (PCDD/Fs) contained in municipal solid waste incineration (MSWI) fly ash during the hydrothermal process was investigated. Influencing factors, such as Fe addition mode, reaction time and cooling procedure after reaction, were tested to evaluate their effects. Experimental results indicated that Fe addition in the form of a mixture of ferrous sulphate and ferric sulphate enhanced decomposition of PCDD/Fs contained in the MSWI fly ash, particularly for the decomposition of 2,3,7,8-tetrachlorodibenzo-dioxin and 2,3,7,8-tetrachlorodibenzo-furan under the reaction temperature of 563 K. The decomposition rate of PCDD/Fs reached 90.33% by international toxicity equivalent (I-TEQ) when Fe was added as a mixture of ferrous and ferric sulphates by 5% (wt/wt) with the Fe (III)/Fe (II) ratio being 2; without Fe addition, the decomposition rate of PCDD/Fs was only 46.17% by I-TEQ in the same process. Fe addition in the form of ferrous sulphate alone also showed an enhancing effect on PCDD/Fs decomposition, but the associated decomposition rates were relatively lower, suggesting iron oxides formed from the mixture of ferric and ferrous sulphates are more favourable catalysts. At the same time, the cooling procedure after the hydrothermal reaction became more flexible if Fe was added in the form of a mixture of ferric and ferrous sulphates. Although a longer reaction time was helpful to increase decomposition rates of PCDD/Fs, 1 h was proved to be a reasonable time under this condition. PMID:23437649

  3. Effect of lubricant oil additive on size distribution, morphology, and nanostructure of diesel particulate matter

    Highlights: • Pour point depressant (PPD) has great impact on particulate matters. • The number of nanoparticles increases sharply after PPD is added. • Ambiguous boundaries can be found when the PPD additive was added. • PPD changes the size distribution into bimodal logarithmic. • Three nanostructure parameters are changed greatly by PPD. - Abstract: Effects of lubricant oil additive on the characterization of particles from a four-cylinder turbocharged diesel engine were investigated. Neat diesel and blended fuel containing oil pour point depressant (PPD) additive were chosen as the test fuels. Effects of different fuels on size distribution, morphology, and nanostructure of the diesel particles were studied. Transmission electron microscopy (TEM) and high resolution TEM (HRTEM) were employed to study the morphology and nanostructure parameters. Particle size distribution was measured by fast particulate spectrometer (DMS 500). According to the experimental results, distribution of the primary particles size of the two fuels conforms to Gaussian distribution, whereas the mean diameter of blended fuel is larger than that of neat diesel at 1200 rpm, which is contrarily smaller at 2400 rpm. Besides, fractal dimension (Df) of aggregates increases close to 2 (Df = 1.991), indicating that the structure became compacter with adding PPD. As to the nanostructure parameters of the blended fuel particles, the layer fringe length decreases from 1.191 nm to 1.064 nm, while both the separation distance and tortuosity increase. The changes in the nanostructure parameters indicate that the particles are more ordered and compressed with burning pure diesel. Results of blended fuel from DMS show that more particles, particularly nucleation mode particles, were discharged. In addition, its size distribution become bimodal logarithmic at 2400 rpm. All these results can provide new information of the effects of oil PPD additive on the formation and characterization of

  4. Gamma ray, EMS and sodium azide induced effectiveness and efficiency of chlorophyll mutations in basmati rice (Oryza sativa L.)

    The effectiveness and efficiency of gamma ray, EMS, sodium azide alone or in combination in relation to chlorophyll mutations in two varieties of Basmati rice (Oryza sativa L.) in M2 generation were studied. The chlorophyll mutations were induced by all the doses of mutagens alone or in combination relatively at a fair frequency in both the varieties in M2 generation. In general, it was found that combination treatments of gamma rays and EMS were observed to be more efficient in Taraori Basmati, while EMS alone and combination treatment of gamma rays and EMS were more efficient in Pusa Basmati 1 on sterility and growth injury basis both. Sodium azide at 0.5 mM was found as the most effective dose in both Taraori Basmati and Pusa Basmati 1 cultivars. (author)

  5. Co-digestion of manure and industrial waste--The effects of trace element addition.

    Nordell, Erik; Nilsson, Britt; Nilsson Påledal, Sören; Karisalmi, Kaisa; Moestedt, Jan

    2016-01-01

    Manure is one of the most common substrates for biogas production. Manure from dairy- and swine animals are often considered to stabilize the biogas process by contributing nutrients and trace elements needed for the biogas process. In this study two lab-scale reactors were used to evaluate the effects of trace element addition during co-digestion of manure from swine- and dairy animals with industrial waste. The substrate used contained high background concentrations of both cobalt and nickel, which are considered to be the most important trace elements. In the reactor receiving additional trace elements, the volatile fatty acids (VFA) concentration was 89% lower than in the control reactor. The lower VFA concentration contributed to a more digested digestate, and thus lower methane emissions in the subsequent storage. Also, the biogas production rate increased with 24% and the biogas production yield with 10%, both as a result of the additional trace elements at high organic loading rates. All in all, even though 50% of the feedstock consisted of manure, trace element addition resulted in multiple positive effects and a more reliable process with stable and high yield. PMID:25812806

  6. Effect of Cephalaria syriaca addition on rheological properties of composite flour

    Karaoðlu, M. M.

    2012-10-01

    The study was carried out to investigate the effect of whole and defatted Cephalaria syriaca flour on the rheological properties of composite flours that used in bran bread production. Cephalaria syriaca products were used to replace 0.25, 0.75, 1.25, 1.75, and 2.25% of wheat-wheat bran composite flour, and its rheological and fermentative properties were measured by farinograph, extensograph and rheofermentometre. The data showed that the rheological parameters of flours were greatly modified by addition of Cephalaria syriaca. The rheological properties of wheatwheat bran composite flour added with whole and defatted Cephalaria syriaca flour were considerably improved with regard to especially extensograph characteristics such as dough resistance, area (energy), ratio number and rheofermentometer parameters such as Hm, T1, Tx, volume loss and gas retention, as compared to control. However addition of Cephalaria syriaca products adversely affected the farinograph characteristics. Generally, these effects of both whole and defatted Cephalaria syriaca flour increased, as the addition level increased. Maximum Tx, gas retention and area (energy) of dough were obtained from wheat-wheat bran composite flour added with 1.75% whole Cephalaria syriaca flour, while the highest dough stability was at addition level of 0.25% whole Cephalaria syriaca flour.

  7. Effect of Pro-Degradation Additive on Photo-Oxidative Aging of Polypropylene Film

    This paper describes the effect of pro-degradation additives (PDA) on photo-oxidative aging of polypropylene (PP) films after being time accelerated in UV-weathering chamber. Thin films (0.12 mm) containing these additives were prepared by sheeting process. The effect of UV on PP films in the presence of these additives was investigated. Changes in the PP films appearance, tensile properties and carbonyl index (CI) were used to investigate the degradation behavior. The films became completely pulverised after 100 h of photo-oxidative treatment and could not be tested further. Films containing PDA showed rapid loss in tensile properties within 100 h of photo-oxidative aging. In addition, the CI results of photo-oxidative films increased with increasing PDA amount within the time interval of aging and the activity was due to the mechanism reaction of PP with PDA particles. During the aging process the material becomes denser due to tighter packing and incorporation of oxygen into the amorphous regions of the polymer. The results indicated that the presence of PDA contributed to the photo degradation and the activity was very much influenced by the amount PDA. (author)

  8. Effect of addition of commercial rosemary extracts on potent odorants in cooked beef.

    Kim, Hun; Cadwallader, Keith R; Kido, Hirotsugu; Watanabe, Yuko

    2013-06-01

    Solid-phase microextraction-gas chromatography-olfactometry (SPME-GCO) and aroma extract dilution analysis (AEDA) were applied to measure the effects of the addition of two commercial rosemary extracts (RE) on the potent odorants in cooked beef extracts (BE). On the basis of the results of SPME-GCO and AEDA, the addition of RE imparted sweet and floral notes to BE as a result of the addition of esters and terpenes of RE. In addition, RE suppressed the formation of odorants derived via lipid oxidation and Maillard reactions. The most potent lipid oxidation volatiles consisted of 1-octen-3-one (mushroom-like), (E)-2,4-epoxy-(E)-2-decenal (metallic), and eight different aldehydes (fatty). The Maillard reaction volatiles, necessary for typical cooked beef flavor, included compounds with meaty [2-methyl-3-furanthiol, 2-methyl-3-(methylthio)furan, 2-methyl-3-(methyldithio)furan], roasty (2-furanmethanethiol), caramel-like [4-hydroxy-2,5-dimethyl-3(2H)-furanone], baked potato-like [3-(methylthio)propanal], and spicy [3-hydroxy-4,5-dimethyl-2(5H)-furanone] attributes. The suppressive effects of RE may be caused by the action of antioxidative substances in RE alone or in combination with the pH increase in BE induced by the matrix components of RE. PMID:23501248

  9. Hailey-Hailey disease: identification of novel mutations in ATP2C1 and effect of missense mutation A528P on protein expression levels.

    Fairclough, Rebecca J; Lonie, Lorne; Van Baelen, Kurt; Haftek, Marek; Munro, Colin S; Burge, Susan M; Hovnanian, Alain

    2004-07-01

    ATP2C1, encoding the human secretory pathway Ca(2+)-ATPase (hSPCA1), was recently identified as the defective gene in Hailey-Hailey disease (HHD), an autosomal dominant skin disorder characterized by abnormal keratinocyte adhesion in the suprabasal layers of the epidermis. In this study, we used denaturing high-performance liquid chromatography to screen all 28 exons and flanking intron boundaries of ATP2C1 for mutations in 9 HHD patients. Nine different mutations were identified. Five of these mutations, including one nonsense, one deletion, two splice-site, and one missense mutation, have not been previously reported. Recently, functional analysis of a series of site-specific mutants, designed to mimic missense mutations found in ATP2C1, uncovered specific defects in Ca(2+) and/or Mn(2+) transport and protein expression in mutant hSPCA1 polypeptides. In order to investigate the molecular and physiological basis of HHD in the patient carrying missense mutation A528P, located in the putative nucleotide binding domain of the molecule, site-directed mutagenesis was employed to introduce this mutation into the wild-type ATP2C1 (hSPCA1) sequence. Functional analyses of HHD-mutant A528P demonstrated a low level of protein expression, despite normal levels of mRNA and correct targeting to the Golgi, suggesting instability or abnormal folding of the mutated hSPCA1 polypeptides. Analogous to conclusions drawn from our previous studies, these results further support the theory of haploinsufficiency as a prevalent mechanism for the dominant inheritance of HHD, by suggesting that the level of hSPCA1 in epidermal cells is critical. PMID:15191544

  10. Effect of additives on enhanced sintering and grain growth in uranium dioxide

    The use of sintering additives has been the most effective way of promoting grain growth of uranium dioxide. We have established a same mechanism for additives which belongs to corundum structure: chromium, aluminium, vanadium and titanium sesquioxides. Study of thermodynamical stabilities of dopants has lead to define suitable sintering atmospheres in order to enhance grain growth. Low solubility limits have been defined at T=1700 deg C for four additives, from variations of final grain size versus initial dopant concentration Identification of second phase after cooling has been done from electronic diffraction patterns. It appears that these solubilities decrease sharply as positive deviation from stoichiometry of uranium dioxide increases. Dilatometric analysis of sintering of doped uranium dioxide has shown in certain cases some enhancement in densification rates, at the point of onset of abnormal grain growth, which is believed to be the source. Nevertheless, the following growth is accompanied with pores coalescence mechanisms and pores entrapment inside grains. Increased thermal stability, during standard annealing, is expected, limiting thereby redensification of nuclear fuel in reactors. Finally, from investigations of additives vaporizations, Al2O3 and Cr2O3, oxygen exchanges between additives and matrix are believed to occur, which should lead to enhance pore mobility. (Author)., refs., figs., tabs

  11. Effect of Ce addition on the mechanical and electrochemical properties of a lithium battery shell alloy

    Zhang, Junchao [School of Materials Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240 (China); Ding, Dongyan, E-mail: dyding@sjtu.edu.cn [School of Materials Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240 (China); Xu, Xinglong [School of Materials Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240 (China); Gao, Yongjin; Chen, Guozhen; Chen, Weigao; You, Xiaohua [Huafon NLM Al Co., Ltd, Shanghai 201506 (China); Huang, Yuanwei; Tang, Jinsong [Shanghai Huafon Materials Technology Institute, Shanghai 201203 (China)

    2014-12-25

    Highlights: • Fabrication of Ce-free and Ce-containing Al–Cu–Mn–Fe–Mg alloy. • TEM, tensile and electrochemical characterization of the alloys. • Ce element greatly affects the precipitation of the alloy. • Ce element had great impact on the tensile strength and corrosion potential of the alloys. - Abstract: Due to severe application environment lithium battery shell of new-energy automotives requires increasing demands for using high performance aluminum alloys. In the present work, effect of Ce addition on the microstructure, tensile and electrochemical properties of an Al–Cu–Mn–Mg–Fe alloy were investigated through using X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM), tensile tests and electrochemical tests. The experimental results indicated that the addition of Ce element could promote the precipitation of second phases. With addition of 0.36% Ce, high melting point Al{sub 8}Cu{sub 4}Ce phase and many Al{sub 20}Cu{sub 2}Mn{sub 3} particles could be found. In addition, the precipitation of conventionally dominant phase of Al{sub 2}Cu could be suppressed in alloy. The Ce addition was found to result in enhanced tensile strength and improved corrosion resistance.

  12. Effect of organic additives on positive electrolyte for vanadium redox battery

    Li Sha [Department of Functional Materials and Chemistry, School of Chemistry and Chemical Engineering, Central South University, Changsha 410083 (China); Huang Kelong, E-mail: lisha_csu@163.com [Department of Functional Materials and Chemistry, School of Chemistry and Chemical Engineering, Central South University, Changsha 410083 (China); Liu Suqin; Fang Dong; Wu Xiongwei; Lu Dan; Wu Tao [Department of Functional Materials and Chemistry, School of Chemistry and Chemical Engineering, Central South University, Changsha 410083 (China)

    2011-06-30

    Highlights: > Four organics as electrolyte additives of vanadium redox battery. > Changes are examined in the electrochemical properties of vanadium redox battery. > D-sorbitol is a suitable additive to the electrolyte for the vanadium redox battery. > The mechanism of improvement is discussed in detail. - Abstract: Fructose, mannitol, glucose, D-sorbitol are explored as additives in electrolyte for vanadium redox battery (VRB), respectively. The effects of additives on electrolyte are studied by cyclic voltammetry (CV), charge-discharge technique, electrochemical impedance spectroscopy (EIS) and Raman spectroscopy. The results indicate that the vanadium redox cell using the electrolyte with the additive of D-sorbitol exhibits the best electrochemical performance (the energy efficiency 81.8%). The EIS results indicate that the electrochemical activity of the electrolyte is improved by adding D-sorbitol, which can be interpreted as the increase of available (-OH) groups providing active sites for electron transfer. The Raman spectra show that VO{sup 2+} ions take part in forming a complex with the D-sorbitol, which not only improve solubility of V(V) electrolyte, but also provide more activity sites for the V(IV)/V(V) redox reaction.

  13. CAN Canopy Addition of Nitrogen Better Illustrate the Effect of Atmospheric Nitrogen Deposition on Forest Ecosystem?

    Zhang, Wei; Shen, Weijun; Zhu, Shidan; Wan, Shiqiang; Luo, Yiqi; Yan, Junhua; Wang, Keya; Liu, Lei; Dai, Huitang; Li, Peixue; Dai, Keyuan; Zhang, Weixin; Liu, Zhanfeng; Wang, Faming; Kuang, Yuanwen; Li, Zhian; Lin, Yongbiao; Rao, Xingquan; Li, Jiong; Zou, Bi; Cai, Xian; Mo, Jiangming; Zhao, Ping; Ye, Qing; Huang, Jianguo; Fu, Shenglei

    2015-06-01

    Increasing atmospheric nitrogen (N) deposition could profoundly impact community structure and ecosystem functions in forests. However, conventional experiments with understory addition of N (UAN) largely neglect canopy-associated biota and processes and therefore may not realistically simulate atmospheric N deposition to generate reliable impacts on forest ecosystems. Here we, for the first time, designed a novel experiment with canopy addition of N (CAN) vs. UAN and reviewed the merits and pitfalls of the two approaches. The following hypotheses will be tested: i) UAN overestimates the N addition effects on understory and soil processes but underestimates those on canopy-associated biota and processes, ii) with low-level N addition, CAN favors canopy tree species and canopy-dwelling biota and promotes the detritus food web, and iii) with high-level N addition, CAN suppresses canopy tree species and other biota and favors rhizosphere food web. As a long-term comprehensive program, this experiment will provide opportunities for multidisciplinary collaborations, including biogeochemistry, microbiology, zoology, and plant science to examine forest ecosystem responses to atmospheric N deposition.

  14. Effect of organic additives on positive electrolyte for vanadium redox battery

    Highlights: → Four organics as electrolyte additives of vanadium redox battery. → Changes are examined in the electrochemical properties of vanadium redox battery. → D-sorbitol is a suitable additive to the electrolyte for the vanadium redox battery. → The mechanism of improvement is discussed in detail. - Abstract: Fructose, mannitol, glucose, D-sorbitol are explored as additives in electrolyte for vanadium redox battery (VRB), respectively. The effects of additives on electrolyte are studied by cyclic voltammetry (CV), charge-discharge technique, electrochemical impedance spectroscopy (EIS) and Raman spectroscopy. The results indicate that the vanadium redox cell using the electrolyte with the additive of D-sorbitol exhibits the best electrochemical performance (the energy efficiency 81.8%). The EIS results indicate that the electrochemical activity of the electrolyte is improved by adding D-sorbitol, which can be interpreted as the increase of available (-OH) groups providing active sites for electron transfer. The Raman spectra show that VO2+ ions take part in forming a complex with the D-sorbitol, which not only improve solubility of V(V) electrolyte, but also provide more activity sites for the V(IV)/V(V) redox reaction.

  15. Effect of Ce addition on the mechanical and electrochemical properties of a lithium battery shell alloy

    Highlights: • Fabrication of Ce-free and Ce-containing Al–Cu–Mn–Fe–Mg alloy. • TEM, tensile and electrochemical characterization of the alloys. • Ce element greatly affects the precipitation of the alloy. • Ce element had great impact on the tensile strength and corrosion potential of the alloys. - Abstract: Due to severe application environment lithium battery shell of new-energy automotives requires increasing demands for using high performance aluminum alloys. In the present work, effect of Ce addition on the microstructure, tensile and electrochemical properties of an Al–Cu–Mn–Mg–Fe alloy were investigated through using X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM), tensile tests and electrochemical tests. The experimental results indicated that the addition of Ce element could promote the precipitation of second phases. With addition of 0.36% Ce, high melting point Al8Cu4Ce phase and many Al20Cu2Mn3 particles could be found. In addition, the precipitation of conventionally dominant phase of Al2Cu could be suppressed in alloy. The Ce addition was found to result in enhanced tensile strength and improved corrosion resistance

  16. The effect of additional high dose carbon implantation on the tribological properties of titanium implanted steel

    The tribological properties and the structural changes of hardened steel implanted with titanium followed by carbon were investigated as a function of additional carbon dose. The dose of Ti was 5.1017 Ti cm-2 and the additional C doses were 0, 4.1017, 8.1017 and 1.2.1018 Ccm-2. After Ti implantation, the steel surface transformed to a Fe-Ti-C ternary amorphous phase. Additional implantation of carbon to a dose of 4.1017 Ccm-2 produced fine TiC precipitates dispersed in the ternary amorphous matrix. When the additional C dose exceeded 8.1017 Ccm-2, very fine graphite precipitates appeared in the ternary amorphous phase. The steel surface with very fine graphite precipitates exhibited superior tribological properties. The benefits provided by additional high dose carbon implantation are considered as follows: strengthening of the amorphous phase, thickening of the modified layer, dispersion strengthening of the implanted layer by very fine graphite precipitates and lubrication effect by graphite particles. Comparing the friction properties of Ti+C implanted steel with that of C implanted steel, the role of Ti implantation is to reduce the friction of the surface during sliding and the role of C implantation is to increase the lifetime of the surface against wear. (orig.)

  17. The longer term effects of zinc addition on cobalt deposition in PWRs

    An experiment has been performed to study the effects of previous zinc addition on the incorporation of cobalt into the oxide layers on typical PWR primary circuit constructional alloys. Cobalt deposition in PWR coolant without zinc addition was compared onto coupons with several surface finishes, including samples pre-oxidised in PWR coolant with or without 50 ppb dissolved zinc and untreated samples. For most alloys the lowest Co-60 deposition rate took place onto coupons which had only been exposed to zinc-containing coolant. For iron-based alloys the highest Co-60 deposition rate took place onto new coupons, whereas for nickel-based alloys the highest Co-60 deposition rate took place onto pre oxidised coupons. The results show that previous zinc addition will reduce the rate of Co-60 build up on out-of-core surfaces in subsequent exposure to zinc-free coolant; however continuous zinc addition will result in greater benefits. The greatest benefits are obtained when surfaces are exposed to zinc before an oxide layer has been formed. Hence for existing plant, zinc addition could be performed following primary circuit decontamination. (author)

  18. The effect of caesium and xenon addition on negative hydrogen ion production

    The presence of caesium in hydrogen discharges is known to increase the extracted negative hydrogen ion current by up to sixteen fold. The mechanism for this phenomenon is not understood. Here Langmuir probe and photodetachment techniques have been used to measure the effects on plasma parameters, including the negative ion density, of adding caesium and xenon to a multicusp ion source. The addition of xenon, also a heavy element but unreactive, allows possible negative ion confinement effects to be explored. No significant change in the negative ion density was observed when up to 20% xenon was introduced, although other plasma parameter changes were observed. Caesium addition increased the negative ion concentration. This increase was found to depend on the wall temperature. copyright 1996 American Institute of Physics

  19. Effects of Germanium Tetrabromide Addition to Zinc Tetraphenyl Porphyrin / Fullerene Bulk Heterojunction Solar Cells

    Atsushi Suzuki

    2014-03-01

    Full Text Available The effects of germanium tetrabromide addition to tetraphenyl porphyrin zinc (Zn-TPP/fullerene (C60 bulk heterojunction solar cells were characterized. The light-induced charge separation and charge transfer were investigated by current density and optical absorption. Addition of germanium tetrabromide inserted into active layer of Zn-TPP/C60 as bulk heterojunction had a positive effect on the photovoltaic and optical properties. The photovoltaic mechanism of the solar cells was discussed by experimental results. The photovoltaic performance was due to light-induced exciton promoted by insert of GeBr4 and charge transfer from HOMO of Zn-TPP to LUMO of C60 in the active layer.

  20. pH effects of the addition of three biochars to acidic Indonesian mineral soils

    Martinsen, V; Alling, V; Nurida, N L;

    2015-01-01

    Soil acidity may severely reduce crop production. Biochar (BC) may increase soil pH and cation exchange capacity (CEC) but reported effects differ substantially. In a systematic approach, using a standardized protocol on a uniquely large number set of 31 acidic soils, we quantified the effect of...... increasing amounts (0–30%; weight:weight) of three types of field-produced BCs (from cacao (Theobroma cacao. L.) shell, oil palm (Elaeis guineensis. Jacq.) shell and rice (Oryza sativa. L.) husk) on soil pH and CEC. Soils were sampled from croplands at Java, Sumatra and Kalimantan, Indonesia. All BCs caused...... a significant increase in mean soil pH with a stronger response and a greater maximum increase for the cacao shell BC addition, due to a greater acid neutralizing capacity (ANC) and larger amounts of extractable base cations. At 1% BC addition, corresponding to about 30 tons ha−1, the estimated...

  1. EFFECT OF COPPER ADDITION ON MECHANICAL PROPERTIES OF 4Cr16Mo

    H.M. Geng; X.C. Wu; Y.A. Min; H.B. Wang; H.K. Zhang

    2008-01-01

    Experiments conducted to determine the effect of copper addition on the machinability of plastic mold steel, 4Cr16Mo, were presented. The machinability of mold steel 4Cr16Mo was visibly improved by adding Cu. The top wear of 4Cr16Mo with copper was less than that without copper. The Cu-rich phase had the effect of a lubricant and the heat conductivity, which reduced cutting-tool wear, improved machinability, and increased the service life of the cutting-tool. Increasing of copper addition decreased the hot-working character of 4Cr16Mo. The optimal hot-working parameters for 4Cr16Mo with copper were determined by the tensile test and the compression test. The rate of deformation should be adopted as 0.6 s-1. The heating-up temperature, initial forging temperature, and terminal forging temperature were 1200℃, 1150℃, and 950℃, respectively.

  2. Effects of oxygen addition to argon glow discharges: A hybrid Monte Carlo-fluid modeling investigation

    A hybrid model is developed for describing the effects of oxygen addition to argon glow discharges. The species taken into account in the model include Ar atoms in the ground state and the metastable level, O2 gas molecules in the ground state and two metastable levels, O atoms in the ground state and one metastable level, O3 molecules, Ar+, O+, O2+ and O- ions, as well as the electrons. The hybrid model consists of a Monte Carlo model for electrons and fluid models for the other plasma species. In total, 87 different reactions between the various plasma species are taken into account. Calculation results include the species densities and the importance of their production and loss processes, as well as the dissociation degree of oxygen. The effect of different O2 additions on these calculation results, as well as on the sputtering rates, is discussed.

  3. Mechanical Effects of Hafnium and Boron Addition to Aluminum Alloy Films for Submicrometer LSI Interconnects

    Onoda, Hiroshi; Takahashi, Eishi; Kawai, Yasuaki; Madokoro, Shoji; Fukuyo, Hideaki; Sawada, Susumu

    1993-11-01

    This is the first report on the mechanical properties of hafnium- and boron-added Al-Si-Cu alloy film for LSI interconnects. Two to three hundred ppm of hafnium and boron addition into Al-Si-Cu alloy film does not influence the Al alloy properties for metal lines as LSI interconnects, such as its low resistivity, low ohmic contact resistance with Si, and fine-line patterning feasibility. The mechanical properties of the Al alloy film, however, change greatly. Vertical hillock and lateral hillock formation is considerably suppressed during heat treatments used in LSI fabrication processes. Stress-induced void formation is also reduced during aging test at 125°C. These effects due to hafnium and boron addition are considered to be an impurity precipitation effect ihat was confirmed by X-ray diffraction analysis and electron probe microanalysis.

  4. Negative effect of the M184V mutation in HIV-1 reverse transcriptase on initiation of viral DNA synthesis

    The M184V mutation in HIV reverse transcriptase (RT) is associated with high-level resistance against the nucleoside inhibitor lamivudine as well as diminished viral replication capacity. We have previously demonstrated that HIV variants containing the M184V mutation were relatively unable to successfully undergo compensatory mutagenesis following deletion of an A-rich loop located upstream of the primer binding site (PBS). To understand the mechanisms involved, we synthesized viral RNA templates containing different compensatory mutations that were emergent during the long-term culture of the A-rich loop-deleted viruses. These templates were then used in cell-free reverse transcription initiation assays and in tRNA primer placement assays performed with either recombinant wild-type RT or recombinant RT containing the M184V substitution. The results showed that the RNA template that contained the A-rich loop deletion was impaired in ability to initiate reverse transcription and that the presence of the M184V substitution in RT amplified this effect. Clearance from pausing at position +3 during synthesis of viral DNA was identified as a sensitive step in this reaction that could not be efficiently bypassed with the M184V mutant enzyme. Increased efficiency of initiation was seen with the deleted RNA templates that also contained mutations identified in the revertant viruses, provided that these mutations facilitated formation of a competent binary tRNA/RNA complex. These findings provide biochemical evidence that initiation of tRNALys3-primed DNA synthesis is an important rate-limiting step in reverse transcription that correlates with viral replication fitness

  5. Functional effects of spinocerebellar ataxia type 13 mutations are conserved in zebrafish Kv3.3 channels

    Mock Allan F

    2010-08-01

    zebrafish Kv3.3 channels are consistent with a role in facilitating fast, repetitive firing of action potentials in neurons. The functional effects of SCA13 mutations are well conserved between human and zebrafish Kv3.3 channels. The high degree of homology between human and zebrafish Kv3.3 channels suggests that the zebrafish will be a useful model system for studying pathogenic mechanisms in SCA13.

  6. Comparative effect of mutation of Aspergillus oryzae by gamma or ultraviolet irradiation

    Ito, Hitoshi; Nessa, A. [Japan Atomic Energy Research Inst., Takasaki, Gunma (Japan). Takasaki Radiation Chemistry Research Establishment

    1994-08-01

    Mutation frequency of Aspergillus oryzae IAM2630 was studied compared with gamma and ultraviolet irradiation. In this study, mutation frequency of morphological changes on survived colonies was increased up to 50% by irradiation of gamma-rays at survival fraction of 10{sup -3} to 10{sup -4} on potato-dextrose agar. On the contrary, mutation frequency of ultraviolet was obtained less than 17% at survival fraction of 10{sup -3}. Mutants with improvement of three-to-five hold production of {alpha}-amylase were isolated by irradiation of gamma-rays at 1.2 kGy. However, we could not isolate any mutants of higher production of {alpha}-amylase by ultraviolet irradiation. (author).

  7. Reaction rate theory of radiation exposure: Effects of the dose rate on mutation frequencies

    Manabe, Yuichiro; Nakamura, Issei

    2014-01-01

    We develop a kinetic reaction model for the cells having the irradiated DNA molecules due to the ionizing radiation exposure. Our theory simultaneously accounts for the time-dependent reactions of the DNA damage, the DNA mutation, the DNA repair, and the proliferation and apoptosis of cells in a tissue with a minimal set of model parameters. In contrast to the existing theories for the radiation exposition, we do not assume the relationships between the total dose and the induced mutation frequency. We show good agreement between theory and experiment. Importantly, our result shows a new perspective that the key ingredient in the study of the irradiated cells is the rate constants depending on the dose rate. Moreover, we discuss the universal scaling function for mutation frequencies due to the irradiation at low dose rates.

  8. Effect of additives in reducing ash sintering and slagging in biomass combustion applications

    Wang, Liang

    2012-07-01

    formation of low temperature melting potassium rich silicates and phosphates, causing severe sintering of the WCob ash at elevated temperatures. In contrast, both the Pioneer corn cob (PCob) and Surcin corn cob (SCob) contained high contents of Cl, Ca and Mg that promote K release from the ashes to a certain extent and inhibit formation of low temperature melting K rich silicates and phosphates. In addition, abundance of Ca and Mg in the PCob and SCob facilitated formation of high temperature melting Ca/Mg-K-silicates and Ca/Mg-K-phosphates, reducing sintering degrees of ashes derived from these two corn cobs. Utilizing additives is an efficient way to mitigate ash related operational problems in biomass combustion applications. The useful additives can be proximately categorized into Al-Si-based, S-based, calcium-based and phosphorus-based, according to the major chemical composition in the additives. After fed into biomass combustion systems with different approaches, the additives can decrease amounts of problematic ash species through five possible mechanisms, which prevent and/or abate ash related problems consequently. It is interesting to exploit additives from waste materials, which are normally characterized with rather high chemical reactivity, physical adsorption capacity, abundance of refractory compounds themselves and low costs. More detailed studies are needed to clarify effects of these additives on ash transformation during biomass combustion processes. Sintering characteristics of biomass ashes and effects of additives were investigated. The work revealed that severe fusion of wheat straw ash was associated with intensive formation and melting of potassium silicates under heating. Whereas, sintering of wood waste ash was caused by generation of low temperature melting potassium/sodium aluminum silicates and potassium/sodium calcium silicates. The best anti-sintering effect was achieved by using the marble sludge as additive. The dilution effect from the

  9. Effect of clay mineral addition on properties of bio-based polymer blends

    Abreu, Ana S.; M. de OLIVEIRA; Machado, A.V.

    2015-01-01

    The effect of clay mineral addition to bio-based blends on morphology and physical properties of thermoplastic starch (TPS) and polypropylene grafted with maleic anhydride (PP-g-MA) was investigated. Blends and nanocomposites containing organoclay, Cloisite 30B, were prepared by melt mixing and characterized by several techniques. X-ray diffraction (XRD), scanning and transmission electron microscopy (SEM, STEM) and dynamic mechanical analysis (DMA) demonstrate a very good dispers...

  10. Effect of cerium addition on microstructure and texture of aluminum foil for electrolytic capacitors

    王海燕; 李文学; 任慧平; 黄丽颖; 王向阳

    2010-01-01

    Anode foil of aluminum electrolytic capacitor,which requires large surface area for high capacitance,were prepared by rolling,annealing and electrochemical etching.Effects of cerium addition on the capacitance of aluminum electrolytic capacitors were investigated.Microstructure of the aluminum foil surface was observed by optical microscopy(OM) and scanning electron microscopy(SEM).Electron back scattered diffraction(EBSD) was also employed to reveal texture evolvement of cold-rolled aluminum foil after ann...

  11. Additive effects of aging and HIV infection on category verbal fluency : an analysis of component processes

    Iudicello, Jennifer E.

    2011-01-01

    Advances in the management of HIV infection have resulted in a growing population of older adults living with HIV. Both aging and HIV infection have been independently associated with central nervous system changes and corresponding declines in neurocognitive functioning. Poorer semantic verbal fluency output is also common in both HIV infection and healthy older adults, although, the possible additive effects of these risk factors are unknown. The present study aimed to examine the combined ...

  12. Effect of liquid sewage sludge addition on atrazine sorption and desorption by soil

    Celis, R.; E. Barriuso; Houot, S.

    1998-01-01

    Liquid sewage sludge (LSS) addition to soil incorporates both insoluble suspended organic material and large amounts of dissolved organic matter (LSSDOM) which can influence the sorption-desorption behaviour of pestieides by soil constituents. Batch sorption isotherm techniques were used to determine the relative effect of the insoluble and dissolved organic matter from a LSS on the sorption and desorption of the herbicide atrazine by soil. Atrazine sorption and desorption isotherms were obta...

  13. Effect of scandium and zirconium additions on the corrosion properties of Al-Mg alloys

    Effect of scandium and zirconium additions and also models of annealing and induced heating on corrosion cracking resistance, stratifying intercrystalline and general corrosion by loss of mass is studied and electrochemical characteristics of semifinished products from Al-Mg-alloys are determined. New regime of stabilizing providing for manufacture of semifinished products with improved level of corrosion is developed. It is shown that electrochemical factor plays an important role in the mechanism of corrosion cracking of the alloys under consideration

  14. The effects of additional kinesio taping over exercise in the treatment of patellofemoral pain syndrome

    Akbas, Eda; Atay, Ahmet Ozgur; Yuksel, Inci

    2011-01-01

    Objective: The purpose of this prospective, randomized, controlled study was to determine the effects of kinesio taping in the treatment of patients with patellofemoral pain syndrome (PFPS). Methods: Thirty-one women with PFPS (mean age: 44.88 years; range: 17 to 50 years) were randomly assigned to either a kinesio taping (KT) (n=15) or control (n=16) group. Both groups received the same muscle strengthening and soft tissue stretching exercises for six weeks and the KT group additionally ...

  15. Effects of Sodium Sulfate as Electrolyte Additive on Electrochemical Performance of Lead Electrode

    YU Jin-yu; QIAN Zhao-hong; ZHAO Meng; WANG Yu-jie; NIU Lin

    2013-01-01

    Sodium sulfate as an electrolyte additive was studied via electrochemical methods including linear sweep voltammetry(LSV),cyclic voltammetry(CV) and electrochemical impedance spectroscopy(EIS) to deeply understand its effect on the hydrogen evolution current and overpotential as well as the formation and structure of anodic passivation films on lead surface during the redox processes.The results achieved will be valuable to improve the cycle life and maintenance-free properties of lead-acid batteries.

  16. The effect of Y2O3 addition on thermal shock behavior of magnesium aluminate spinel

    Pošarac Milica; Devečerski A.; Volkov-Husović T.; Matović B.; Minić D.M.

    2009-01-01

    The effect of yttria additive on the thermal shock behavior of magnesium aluminate spinel has been investigated. As a starting material we used spinel (MgAl2O4) obtained by the modified glycine nitrate procedure (MGNP). Sintered products were characterized in terms of phase analysis, densities, thermal shock, monitoring the damaged surface area in the refractory specimen during thermal shock and ultrasonic determination of the Dynamic Young modulus of elasticity. It was found that a new phase...

  17. UNDERSTANDING THE EFFECTS OF SURFACTANT ADDITION ON RHEOLOGY USING LASER SCANNING CONFOCAL MICROSCOPY

    White, T

    2007-05-08

    The effectiveness of three dispersants to modify rheology was examined using rheology measurements and laser scanning confocal microscopy (LSCM) in simulated waste solutions. All of the dispersants lowered the yield stress of the slurries below the baseline samples. The rheology curves were fitted reasonably to a Bingham Plastic model. The three-dimensional LSCM images of simulants showed distinct aggregates were greatly reduced after the addition of dispersants leading to a lowering of the yield stress of the simulated waste slurry solutions.

  18. Effects of Honey Addition on Antioxidative Properties of Different Herbal Teas

    Toydemir Gamze; Capanoglu Esra; Kamiloglu Senem; Firatligil-Durmus Ebru; Sunay Asli E.; Samanci Taylan; Boyacioglu Dilek

    2015-01-01

    Tea and herbal infusions are among the major contributors of phenolic compounds, specifically flavonoids, in our daily diet. Honey is another antioxidant-rich food that is widely used as a natural sweetener. In this work, the effects of honey addition on antioxidant properties of different herbal teas were investigated. For this purpose, 2 different types of honey (flower and pine honey) were added into 9 different herbal teas (melissa, green tea, rosehip, sage, echinacea, fennel, linden, dai...

  19. Effect of Chitin Addition to the Growth of Entomopathogenic fungi Penicillium sp.

    Nurariaty, Agus; Ade, Sugiarti

    2014-01-01

    Penicillium sp. is one of the potentially entomopathogenic fungi to control the cacao pod borer (CPB). The study aims to determine the effect of chitin addition to the growth of entomopathogenic fungi Penicillium sp. Experiments was conducted in Pests Identification and Biological Control laboratory, Department of Plant Pest and Disease, Faculty of Agriculture, Hasanuddin University. The method was conducted that if the fungus Penicillium sp. has grown on PDA, then put in erlemeyer contai...

  20. Aspirin has little additional anti-platelet effect in healthy volunteers receiving prasugrel

    LEADBEATER, P D M; Kirkby, N S; Thomas, S.(Rutgers, The State University of New Jersey, Piscataway, USA); DHANJI, A-R; Tucker, A T; MILNE, G L; Mitchell, J. A.; Warner, T D

    2011-01-01

    Summary Background: Strong P2Y12 blockade, as can be achieved with novel anti-platelet agents such as prasugrel, has been shown in vitro to inhibit both ADP and thromboxane A2-mediated pathways of platelet aggregation, calling into question the need for the concomitant use of aspirin. Objective: The present study investigated the hypothesis that aspirin provides little additional anti-aggregatory effect in a group of healthy volunteers taking prasugrel. Study participants/methods: In all, 9 m...

  1. Effect of addition of human follicular fluid on progesterone secretion by cultured sheep granulosa cells.

    Kumari, G L; Vohra, S; Raghavan, V

    1982-10-01

    The effect of addition of human follicular fluid to cultures of granulosa cells of large sheep follicles (4-6 mm in diameter) on basal and LH-stimulated progesterone secretion was investigated. Both luteinization and progesterone secretion were inhibited by addition of 10% (w/v) charcoal-treated follicular fluid from medium (2-6 mm) and large (7-16 mm) follicles which had low concentrations of estradiol-17 beta, progesterone and LH. In comparison, the fluid from large follicles, having high levels of the same hormones, stimulated both the parameters, and addition of LH along with the fluid had no further effect. Fluid collected from cystic follicles appeared to be stimulatory which also had elevated levels of estradiol-17 beta and progesterone. These findings indicate the presence of both the inhibitors and stimulators of luteinization in human follicular fluid. The effectiveness of any of them either to inhibit or stimulate luteinization probably will depend upon the composition of the follicular fluid and the stage of maturation of the follicles from which it was collected. PMID:6218983

  2. The effect of alloy additives on the phase stability of zirconia-calcia-titania ceramics

    In this study, the effect of alloy additives (NiCr alloys) 011 the phase stability of ZrO2-CaO-TiO2 ceramics has been investigated by means of X-ray diffraction. The results show that the additions of NiCr alloy will restrain the detrimental effect of TiO2 on the phase stabilily in CaO-stabilised ZrO2 ceramics. Furthermore, scanning electron microscopy (SEM) and energy dispersive x-ray spectroscopy (EDX) studies show that TiO2 accumulates in the NiCr phase and the content of TiO2 in the surrounding ZrO2 phase is reduced. The removal of TiO2 from ZrO2 to the NiCr phase may explain why the detrimental effect of TiO2 on cubic ZrO2 phase stability is reduced by the addition of NiCr. (author)

  3. Effect of Skimmed-Milk and Starter Addition on Lactic Acid Formation in Soyghurt

    Yanna Syamsuddin

    2013-01-01

    Full Text Available Research on Effect of Skimmed-Milk and Starter Addition on Lactic Acid Formation in Soyghurt has been done. Soyghurt is a probiotic drinking product made from soy-milk produced by fermentation process using lactic acid bacteria. The bacteria used as starter was Lactobacillus bulgaricus and Streptococcus thermophillus. The objective of this research was to evaluate the effect of skimmed-milk and starter addition on the formation of lactic acid. Variables used in this research was skimmed-milk concentration of 5, 10, and 15% and starter concentration of 3, 5, and 7%, based on volume of soy-milk used as raw material. The soy-milk used was analyzed for its carbohydrate and protein content, and the soyghurt produced was analyzed for its lactic acid, pH and syneresis. The result showed that carbohydrate and protein content in soy-milk was 122.39 mg/L and 2.75%, respectively. The best condition of this process was the addition of 15% skimmed-milk and 5% starter, which yielded the highest lactic acid of 15% with pH of 4.23 and syneresis of 15%. It can be concluded that increasing skimmed-milk concentration cause the increase in lactic acid formation and decrease pH and syneresis. While effect of starter concentration on product analysis was influenced by the amount of nutrition contain in soy-milk.

  4. Ultrasonic Degradation of Fuchsin Basic in Aqueous Solution: Effects of Operating Parameters and Additives

    Rui-Jia Lan

    2013-01-01

    Full Text Available Ultrasonic degradation is one of the recent advanced oxidation processes (AOPs and proven to be effective for removing low-concentration organic pollutants from aqueous solutions. In this study, removal of fuchsin basic from aqueous solutions by ultrasound was investigated. The effects of operating parameters such as ultrasound power (200 W–500 W, initial pH (3–6.5, and temperature (15, 22, 35, and 60°C on the ultrasonic degradation were studied. The degradation of fuchsin under ultrasound irradiation basic was found to obey pseudo first-order reaction kinetics. Addition of catalyst Fe(II had a markedly positive effect on degradation. 84.1% extent of degradation was achieved at initial dye concentration 10 μmol L−1, ultrasound power 400 W, ultrasound frequency 25 kHz, dosage of Fe(II 4 mg L−1, initial pH 6.5, and temperature 22°C. But addition of heterogeneous catalyst TiO2 affected degradation slightly. Addition of radical scavenger suppressed fuchsin basic degradation significantly.

  5. Experimental investigation into the effects of coolant additives on boiling phenomena in pressurized water reactors

    This study investigates the effects of coolant additives like boric acid on boiling phenomena in pressurized water reactors under conditions as realistic as possible. The effects covered range from subcooled boiling to critical boiling conditions (CHF). The focus of this project lies on flow boiling with up to 40 bar and 250 °C in order to generate a data basis for a possible extrapolation to reactor conditions. The results of the experiments are used to implement and validate new models into CFD-Codes in context to a nationwide German joint research project with the specific aim of improving CFD boiling-models. (author)

  6. Priming effect of substrate addition in soil-based biodegradation tests.

    Shen, J; Bartha, R.

    1996-01-01

    To test whether substrate addition changes background CO2 evolution of soil, we measured both 14CO2 and net CO2 evolution from various test compounds. Glucose caused a priming effect, defined as substrate-stimulated soil organic matter mineralization. Formate, benzoate, n-hexadecane, and bis(2-ethylhexyl)phthalate caused no priming, and phenol caused only a transient one. The priming effect of glucose appears to be unusual and does not require a general rejection of net CO2 evolution measurem...

  7. Complete positivity, finite-temperature effects, and additivity of noise for time-local qubit dynamics

    Lankinen, Juho; Lyyra, Henri; Sokolov, Boris; Teittinen, Jose; Ziaei, Babak; Maniscalco, Sabrina

    2016-05-01

    We present a general model of qubit dynamics which entails pure dephasing and dissipative time-local master equations. This allows us to describe the combined effect of thermalization and dephasing beyond the usual Markovian approximation. We investigate the complete positivity conditions and introduce a heuristic model that is always physical and provides the correct Markovian limit. We study the effects of temperature on the non-Markovian behavior of the system and show that the noise additivity property discussed by Yu and Eberly [Phys. Rev. Lett. 97, 140403 (2006), 10.1103/PhysRevLett.97.140403] holds beyond the Markovian limit.

  8. The effect of lime addition on the combustion properties and sulfur contents of three different coals

    Ozbas, K.E.; Hicyilmaz, C.; Kok, M.V. [Middle East Technical University, Ankara (Turkey)

    2002-07-01

    In this research, combustion characterization of 3 different coals of Turkey, from the Soma, Tuncbilek, and Afsin Elbistan regions, were investigated with thermal analysis techniques such as differential scanning calorimetry (DSC) and thermogravimetry (TG/DTG). Lime was added to these coals in concentrations of 3, 7, and 10% by weight to investigate the change in combustible sulfur content and sulfur in ash. It was observed that lime has a positive effect on sulfur emission. Kinetic analysis was also performed to see the effect of lime addition on combustion properties and reaction parameters of the coal samples studied.

  9. On effective and efficient mutation analysis for unit and integration testing

    Just, René

    2013-01-01

    Software testing is the most common technique to verify that a program meets certain quality standards. Sufficient manual testing is not only time consuming but also an error-prone task. Additionally, due to the rapidly growing size and complexity of software systems, automating the software testing process is desirable for more cost-effective testing. Besides automating the testing process, the quality of the applied testing strategy has to be assessed to achieve reliable results. This is of...

  10. Elastatinal and leupeptin: effects on u.v.-induced mutation and sister-chromatid exchanges in Chinese hamster cells

    Microbial protease inhibitors elastatinal and leupeptin were tested for cytotoxicity and for effects on spontaneous and u.v.-induced 6-thioguanine-resistant (6TGr) mutation and sister-chromatid exchange (SCE) in V79 Chinese hamster cells. Continuous treatment with elastatinal exhibited marked cytotoxicity, while leupeptin was almost non-cytotoxic. Elastatinal rapidly induced cytotoxic effects as a function of its concentration and time of exposure. Near maximum cytotoxicity was reached after exposure of 6-8 h and this was partially abolished by the presence of 2.5 micrograms cycloheximide per ml. Concentrations of either protease inhibitor which gave 60-80% survival had no appreciable effects on u.v. survival and frequencies of spontaneous and u.v.-induced 6TGr mutation and SCE. However, reconstruction experiments revealed that pretreatments of 6TGr and 6TGs (wild-type) cells with these inhibitors for 6 days tended to block metabolic co-operation in their co-cultures. Thus, elastatinal and leupeptin are neither clastogenic mutagenic by themselves, and do not alter mutation fixation and expression

  11. Effective additional gamma dose for general population and workers from a Mexican radioactive waste site

    The environmental effective gamma-dose rate has been determined at the Mexican Storage Centre for Radioactive Waste (SCRW) and surrounding communities. Soil samples were analysed for 226Ra, 235U, 137Cs and 40K concentration activities. The outdoor effective gamma dose rate was higher at the SCRW where industrial radioactive sources and uranium ore piles were stored in the past. Some nearby locations, where the action of the rain on the piles promoted the transport and surface migration of 226Ra, 235U and 137Cs, also showed an increased gamma dose rate. The gamma dose rate at distant communities (local background) was evaluated with data obtained along 10 years measurements. The additional effective external dose for the general public at the 200 m neighbouring zone of the site, was two times higher than that from the local background. The outdoor average external effective dose for workers due to the SCRW operation was 20 times than for the local background

  12. The Additive Effects of Core Muscle Strengthening and Trunk NMES on Trunk Balance in Stroke Patients

    Ko, Eun Jae; Kim, Dae Yul; Yi, Jin Hwa; Kim, Won; Hong, Jayoung

    2016-01-01

    Objective To investigate an additive effect of core muscle strengthening (CMS) and trunk neuromuscular electrical stimulation (tNEMS) on trunk balance in stroke patients. Methods Thirty patients with acute or subacute stroke who were unable to maintain static sitting balance for >5 minutes were enrolled and randomly assigned to 3 groups, i.e., patients in the CMS (n=10) group received additional CMS program; the tNMES group (n=10) received additional tNMES over the posterior back muscles; and the combination (CMS and tNMES) group (n=10) received both treatments. Each additional treatment was performed 3 times per week for 20 minutes per day over 3 weeks. Korean version of Berg Balance Scale (K-BBS), total score of postural assessment scale for stroke patients (PASS), Trunk Impairment Scale (TIS), and Korean version of Modified Barthel Index (K-MBI) were evaluated before and after 3 weeks of therapeutic intervention. Results All 3 groups showed improvements in K-BBS, PASS, TIS, and K-MBI after therapeutic interventions, with some differences. The combination group showed more improvements in K-BBS and the dynamic sitting balance of TIS, as compared to the CMS group; and more improvement in K-BBS, as compared to the tNMES group. Conclusion The results indicated an additive effect of CMS and tNMES on the recovery of trunk balance in patients with acute or subacute stroke who have poor sitting balance. Simultaneous application of CMS and tNMES should be considered when designing a rehabilitation program to improve trunk balance in stroke patients. PMID:26949681

  13. Assessing the effect, on animal model, of mixture of food additives, on the water balance

    Mariola Friedrich

    2013-03-01

    Full Text Available Purpose. The purpose of this study was to determine, on the animal model, the effect of modifi cation of diet composition and administration of selected food additives on water balance in the body. Material and methods. The study was conducted with 48 males and 48 females (separately for each sex of Wistar strain rats divided into four groups. For drinking, the animals from groups I and III were receiving water, whereas the animals from groups II and IV were administered 5 ml of a solution of selected food additives (potassium nitrate – E 252, sodium nitrite – E 250, benzoic acid – E 210, sorbic acid – E 200, and monosodium glutamate – E 621. Doses of the administered food additives were computed taking into account the average intake by men, expressed per body mass unit. Having drunk the solution, the animals were provided water for drinking. Results. The mixture of selected food additives applied in the experiment was found to facilitate water retention in the body both in the case of both male and female rats, and differences observed between the volume of ingested fl uids and the volume of excreted urine were statistically signifi cant in the animals fed the basal diet. The type of feed mixture provided to the animals affected the site of water retention – in the case of animals receiving the basal diet analyses demonstrated a signifi cant increase in water content in the liver tissue, whereas in the animals fed the modifi ed diet water was observed to accumulate in the vascular bed. Conclusion. Taking into account the fact of water retention in the vascular bed, the effects of food additives intake may be more adverse in the case of females.

  14. Synergistic effect between nano-ceramic lubricating additives and electroless deposited Ni-W-P coating

    Chen, Min; Cheng, Wushan; Zhao, Zuxin; Huang, Xiaobo

    2013-01-01

    The major solving ways for the material wear are surface modification and lubrication. Currently, the researches at home and abroad are all limited to the single study of either nano-lubricating oil additive or electroless deposited coating. The surface coating has high hardness and high wear resistance, however, the friction reduction performance of the coating with high hardness is not good, the thickness of the coating is limited, and the coating can not regenerate after wearing. The nano-lubricating additives have good tribological performance and self-repair function, but under heavy load, the self-repair rate to the worn surface with the nano-additives is smaller than the wearing rate of the friction pair. To solve the above problems, the Ni-W-P alloy coating and deposition process with excellent anti-wear, and suitable for industrial application were developed, the optimum bath composition and process can be obtained by studying the influence of the bath composition, temperature and PH value to the deposition rate and the plating solution stability. The tribological properties as well as anti-wear and friction reduction mechanism of wear self-repair nano-ceramic lubricating additives are also studied. The ring-block abrasion testing machine and energy dispersive spectrometer are used to explore the internal relation between the coating and the nano-lubricating oil additives, and the tribology mechanism, to seek the synergetic effect between the two. The test results show that the wear resistance of Ni-W-P alloy coating (with heat treatment and in oil with nano-ceramic additives) has increased hundreds times than 45 steel as the metal substrate in basic oil, the friction reduction performance is improved. This research breaks through the bottleneck of previous separate research of the above-mentioned two methods, and explores the combination use of the two methods in industrial field.

  15. The effect of dielectric properties of sintering additives on microwave sintered silicon nitride ceramics.

    Chockalingam, Sreekumar; George, Jacob; Earl, David; Amarakoon, Vasantha R W

    2008-01-01

    Silicon nitride requires the use of susceptive additives for microwave liquid phase sintering due to the material's low dielectric loss. In this article, we report the effect of complex dielectric properties of two compositions of sintering aids on 2.45 GHz microwave sintered Si3N4 with respect to power absorption, temperature distribution and densification behavior. The temperature dependent dielectric properties were measured from 25 degrees C to 1400 degrees C using a conventional cavity perturbation technique. Finite Difference Time Domain (FDTD) electromagnetic simulations coupled with a thermal solver was used to predict the microwave power absorption and the corresponding temperature evolution inside the samples. The additive with higher dielectric loss (4 wt% MgO, 6 wt% Y2O3 and 2.5 wt% ZrO2) produces a greater sintered density than the lower loss additive (4 wt% MgO and 6 wt% Y2O3) or pure Si3N4. Although microwave loss at temperatures below 600 degrees C is insignificant with or without the additives, the loss begins to increase at higher temperatures when the additives are present and has a strong upward trend above 1000 degrees C. Above 1200 degrees C the sample containing ZrO2 exhibited the greatest loss. Numerical simulations at the peak sintering temperature show greater microwave power absorption and higher temperature in the sample with the highest loss additive. The simulation results correlate to the difference in densification behavior observed. The simulation was also useful because the material temperature was not accurately provided by optical pyrometer measurements of the crucible sample holder. PMID:19227072

  16. Additive effects of physical exercise and environmental enrichment on adult hippocampal neurogenesis in mice

    Klaus Fabel

    2009-11-01

    Full Text Available Voluntary physical exercise (wheel running, RUN and environmental enrichment (ENR both stimulate adult hippocampal neurogenesis but do so by different mechanisms. RUN induces precursor cell proliferation, whereas ENR exerts a survival-promoting effect on newborn cells. In addition, continued RUN prevented the physiologically occurring age-related decline in precursor cell in the dentate gyrus but did not lead to a corresponding increase in net neurogenesis. We hypothesized that in the absence of appropriate cognitive stimuli the potential for neurogenesis could not be realized but that an increased potential by proliferating precursor cells due to RUN could actually lead to more adult neurogenesis if an appropriate survival-promoting stimulus follows the exercise. We thus asked whether a sequential combination of RUN and ENR (RUNENR would show additive effects that are distinct from the application of either paradigm alone. We found that the effects of 10 days of RUN followed by 35 days of ENR were additive in that the combined stimulation yielded an approximately 30% greater increase in new neurons than either stimulus alone, which also increased neurogenesis. Surprisingly, this result indicates that although overall the amount of proliferating cells in the dentate gyrus is poorly predictive of net adult neurogenesis, an increased neurogenic potential nevertheless provides the basis for a greater efficiency of the same survival-promoting stimulus. We thus propose that physical activity can “prime” the neurogenic region of the dentate gyrus for increased neurogenesis in the case the animal is exposed to an additional cognitive stimulus, here represented by the enrichment paradigm.

  17. Effect of amino acid mutation at position 127 in 3A of a rabbitattenuated foot-and-mouth disease virus serotype Asia1 on viral replication and infection

    Aiguo; Xin; Mingwang; Zhu; Qi; Hu; Haisheng; Miao; Zhenqi; Peng; Yuwen; He; Lin; Gao; Huachun; Li

    2014-01-01

    An amino acid mutation(R127→I) in the 3A non-structural protein of an FMDV serotype Asia1 rabbit-attenuated ZB strain was previously found after attenuation of the virus. To explore the effects of this mutation on viral replication and infection, the amino acid residue isoleucine(I) was changed to arginine(R) in the infectious cDNA clone of the rabbit-attenuated ZB strain by sitedirected mutagenesis, and the R127-mutated virus was rescued. BHK monolayer cells and suckling mice were inoculated with the R127-mutated virus to test its growth property and pathogenicity, respectively. The effects of the R127 mutation on viral replication and virulence were analyzed. The data showed that there was a slight difference in plaque morphology between the R127-mutated and wild-type viruses. The growth rate of the mutated virus was lower in BHK-21 cells and its virulence in suckling mice was also attenuated. This study indicates that the R127 mutation in 3A may play an important role in FMDV replication in vitro and in pathogenicity in suckling mice.

  18. Use of induced mutations for crop improvement programmes in Sri Lanka

    The use of radiation induced mutations is an effective additional tool for plant breeding work in Sri Lanka. Mutation Breeding could be effectively utilized to create favourable specific changes such as short culms, 90o resistance to pests and diseases, improvement in grain quality etc

  19. Effect of methylene methanedisulfonate as an additive on the cycling performance of spinel lithium titanate electrode

    In order to overcome the poor cyclability of lithium-ion batteries with spinel lithium titanate (Li4Ti5O12), methylene methanedisulfonate (MMDS) is evaluated as electrolyte additive. The linear sweep voltammetry (LSV) and electrochemical impedance spectroscopy (EIS) indicate that MMDS participates in the formation process of the solid electrolyte interface (SEI) film above 1 V, which is due to the interfacial reaction between the electrode and electrolyte: Li4Ti5O12 anodes are previously considered free from SEI films when cycled between 1 and 3 V. The stable SEI film around Li4Ti5O12 is seen most effective as a barrier layer in suppressing the interfacial reaction and resulting gassing from the Li4Ti5O12 surface. In addition, the results of electrochemical impedance spectroscopy (EIS), X-ray photoelectron spectroscopy (XPS), scanning electron microscope (SEM) and transmission electron microscopy (TEM) demonstrate that a thin and good conductive film can be formed on the Li4Ti5O12 surface ascribed to MMDS additive, which resulting the improvement of conductivity and a good ability of Li+ migration. - Highlights: • MMDS used as additive to improve cycling performance of the Li4Ti5O12/Li cells. • A SEI film can be formed using MMDS in the electrolyte above 1 V. • Sulfur-containing species is the main component of the SEI formed by MMDS

  20. Effect of a bacterial inoculum and additive on dry matter in situ degradability of sugarcane silage

    Jos A Reyes-Gutirrez; Oziel D Montaez-Valdez; Ramn Rodrguez-Macias; Mario Ruz-Lpez; Eduardo Salcedo-Prez; Cndido E Guerra-Medina

    2015-01-01

    The objective of this study was to evaluate the effect of adding a bacterial inoculum and a handmade additive to sugarcane silage (SCS) on the in situ digestibility of dry matter (DM). The treatments were:T1) sugarcane silage (SCS) and T2) sugar-cane silage with 1%inoculum and 1%additive (SCS+). The bacterial inoculum consisted of 10.0%molasses, 1.0%yogurt, 5.0%chicken manure, 0.5%urea, and 83.0%water, and the additive was formulated with 1.0%urea, 0.1%ammonium sulfate, and 0.25%phosphorus. In situ dry matter digestibility (DMD) was determined using the nylon bag technique with four cows equipped with ruminal ifstulas. Cows were fed with ensiled sugarcane supplemented with 1 kg of commercial concentrate. 5 g of ground sample for each sugarcane treatment were weighted in nylon bags and incubated for 4, 8, 12, 24, 48, and 72 h in a completely randomized design with six replicates. The DMD (%) was higher (P<0.05) for SCS+for al incubation times when compared with SCS. There were no differences in ruminal pH between the treatments for al the incubation times. The data suggested that the sugarcane silage with bacterial inoculum and additive could be an alternative for providing forage for ruminants during the season of low growth and quality grass.

  1. Effect of copolymer and additive concentrations on the behaviors of mesoporous tungsten oxide

    Lai, W.H. [Department of Materials Science and Engineering, National Cheng Kung University, Tainan 70101, Taiwan (China)]. E-mail: Jeffrey@mail.mse.ncku.edu.tw; Shieh, J. [National Nano Device Laboratories, Hsinchu 30050, Taiwan (China); Teoh, L.G. [Department of Materials Science and Engineering, National Cheng Kung University, Tainan 70101, Taiwan (China); Hung, I.M. [Department of Materials Science and Engineering, National Cheng Kung University, Tainan 70101, Taiwan (China); Liao, C.S. [Department of Materials Science and Engineering, National Tsing Hua University, Hsinchu 30050, Taiwan (China); Hon, M.H. [Department of Materials Science and Engineering, National Cheng Kung University, Tainan 70101, Taiwan (China); Da Yeh University, 112 Shan-Jiau Road, Da-Tsuen, Chang-hua 51542, Taiwan (China)

    2005-06-21

    Nanostructured tungsten oxide films exhibit a series of interesting behaviors due to their excellent properties of photochromic reaction and gas sensing. Mesoporous films with a large surface area are desirable to improve their performance. The main purpose of this study is to elucidate the effects of the copolymer and additive concentrations on the microstructure of the mesoporous tungsten oxide prepared by a sol-gel method. The typical calcined tungsten oxide samples synthesized by L62 and P123 exhibit a Brunauer-Emmett-Teller (BET) surface area of 156 and 138 m{sup 2}/g, respectively. The pore size of 4-10 nm in the sample increases with increasing copolymer concentration. For different additive conditions synthesized by a triblock copolymer, HCl or distilled deionized water (DDW) additive could further promote the BET surface area of mesoporous tungsten oxide than an additive of NaOH, which can be attributed to the stabilization of the micellization in acid media. The sol-gel tungsten oxide involving the use of nonionic triblock copolymer as the templates with disorder pores exhibits outstanding sensitivity in photochromic and gas-sensing properties. Mesoporous tungsten oxide powder synthesized by triblock copolymer exhibits a high transmittance with an indirect E {sub G} of 3.73 eV. Gas-sensing measurement reveals excellent recovery and sensitivity under low gas concentration, low operation temperature for mesoporous tungsten oxide film and a sensitivity of 25 as exposed to 20 ppm NO gas at 40 deg. C.

  2. Effect of additives on the anisotropic etching of silicon by using a TMAH based solution

    Jun, Ki-Hwa; Kim, Bum-Joon; Kim, Jung-Sik

    2015-09-01

    In this study, the anisotropic etching properties of single crystal silicon were examined using a tetramethyl ammonium hydroxide (TMAH). The variations in the Si etching rate and surface morphology at different etching temperatures and TMAH concentrations were evaluated. The effects of different additives were also examined. As the THAM concentration (10-25 wt. %) decreased, the etching rate increased from 10 μm/h to 70 μm/h at temperatures between 70°C and 90°C. On the other hand, the etched surface roughness became degraded as the hillock density and corner undercut ratio increased. To solve these problems, four additives, pyrazine, ammonium persulfate (AP), ammonium hydrogen sulfate (AHS), and isopropyl alcohol (IPA), were added to the TMAH solution. The experimental results showed that these additives play an important role in increasing the etching rate up to 10-20%. The etched surface was also improved significantly by the decreased hillock density on the surface. The addition of IPA to the TMAH solution showed excellent results in improving the etched surface flatness and the undercutting compensation. On the other hand, one of the characteristics of IPA is the decrease in etching rate with increasing amount of IPA. [Figure not available: see fulltext.

  3. Effect of additives on electrochemical performance of lithium nickel cobalt manganese oxide at high temperature

    Kang, Kyoung Seok; Choi, Suneui; Song, JunHo; Woo, Sang-Gil; Jo, Yong Nam; Choi, Jungkyu; Yim, Taeeun; Yu, Ji-Sang; Kim, Young-Jun

    2014-05-01

    Lithium-nickel-cobalt-manganese oxide, Li[NixCoyMnz]O2 (NCM) is a low-cost cathode material with a high capacity and a moderately high rate capability, however, it still suffers from poor electrochemical performance. In this study, several types of additives are attempted to enhance the surface stability of high-Ni-content (Ni ≥ 60%) cathodes and the most effective additive turns out to be PS. The cycle performance in the presence of 2% PS is much improved at a high temperature of 60 °C: (1) 98.9% of its initial capacity is preserved, (2) the increase in thickness is only 17.9%, preventing undesired swellings, and (3) gases are not generated in large amounts with the internal pressure being 56.4 kPa. The FT-IR spectroscopy results suggest that the surface of the cathode in the presence of 2% PS is covered with a film of alkyl sulfone components (RSOSR and RSO2SR), which is possibly formed by the electrochemical oxidation of PS. The current results confirm that the electrochemical performance of Ni-rich cathodes can be improved via the appropriate use of additives. They also indicate that among the tested additive candidates in this study, PS is highly desirable for enhancing the electrochemical performance of Ni-rich cathodes.

  4. Effects of AI Addition on the Thermoelectric Properties of Zn-Sb Based Alloys

    CUI Jiaolin; LIU Xianglian; YANG Wei; CHEN Dongyong; MAO Liding; QIAN Xin

    2009-01-01

    The β-Zn4Sb3, emerged as a compelling p-type thermoelectric material, is widely used in heat-electricity conversion in the 400-650 K range. In order to probe the effects of slight doping on the crystal structure and physical properties, we prepared the samples of Al-added Zn-Sb based alloys by spark plasma sintering and evaluated their microstructures and thermoelectric properties. After a limited Al addition into the Zn-Sb based alloys we observed many phases in the alloys, which include a major phase β-Zn4Sb3,intermetallic phases ZnSb and AISb. The major β-Zn4Sb3 phase plays a fundamental role in controlling the thermoelectric performance, the precipitated phases ZnSb and AISb are of great importance to tailor the transport properties, such as the gradual enhancement of lattice thermal conductivity, in spite of an increased phonon scattering in additional grain boundaries. The highest thermoelectric figure of merit of 0.55 is obtained for the alloy with a limited AI addition at 653 K, which is 0.08 higher than that of un-doped β-Zn4Sb3 at the corresponding temperature. Physical property experiments indicate that there is a potentiality for the improvement of thermoelectric properties if a proper elemental doping is carried out into the Zn-Sb based alloys, which was confirmed by AI addition in the present work.

  5. Effect of Additives on Melting Point of LATS Refining Ladle Slag

    WANG Hong-ming; LI Gui-rong; DING Zhen-tao; DAI Qi-xun; LI Bo

    2007-01-01

    To avoid slag sticking on the ladle immersion cover during the LATS refining and alloying process, the effect of Al2O3 on the melting point of the ladle slag was studied and the additives including CaF2, B2O3, Li2O, and CaO were used to decrease the melting point of the ladle slag. The melting point was measured using the hemisphere method. The results show that the addition of Al2O3 to the ladle slag increases the melting point. The fluxing action is not remarkable if only CaF2 or CaO is used as the additive. The fluxing action of the composite additive obtained by the mixing of CaO and CaF2 in the mass proportion of wCaO∶wCaF2=2∶1 is preferred. The fluxing action of B2O3 is also notable. When the B2O3 content in mass percent is in the range from 2% to 10%, the corresponding melting point is 1 380 ℃ to 1 290 ℃. The fluxing action of Li2O is the most remarkable. When the Li2O content is up to 5%, the melting point of the slag is lower than 1 300 ℃.

  6. Effect of copolymer and additive concentrations on the behaviors of mesoporous tungsten oxide

    Nanostructured tungsten oxide films exhibit a series of interesting behaviors due to their excellent properties of photochromic reaction and gas sensing. Mesoporous films with a large surface area are desirable to improve their performance. The main purpose of this study is to elucidate the effects of the copolymer and additive concentrations on the microstructure of the mesoporous tungsten oxide prepared by a sol-gel method. The typical calcined tungsten oxide samples synthesized by L62 and P123 exhibit a Brunauer-Emmett-Teller (BET) surface area of 156 and 138 m2/g, respectively. The pore size of 4-10 nm in the sample increases with increasing copolymer concentration. For different additive conditions synthesized by a triblock copolymer, HCl or distilled deionized water (DDW) additive could further promote the BET surface area of mesoporous tungsten oxide than an additive of NaOH, which can be attributed to the stabilization of the micellization in acid media. The sol-gel tungsten oxide involving the use of nonionic triblock copolymer as the templates with disorder pores exhibits outstanding sensitivity in photochromic and gas-sensing properties. Mesoporous tungsten oxide powder synthesized by triblock copolymer exhibits a high transmittance with an indirect E G of 3.73 eV. Gas-sensing measurement reveals excellent recovery and sensitivity under low gas concentration, low operation temperature for mesoporous tungsten oxide film and a sensitivity of 25 as exposed to 20 ppm NO gas at 40 deg. C

  7. EFFECT OF DIETARY HYACINTH BEANS (Lablab purpureus AND ENZYME ADDITIVES ON PERFORMANCE OF BROILERS

    Husham Ismail RAGAB

    2015-11-01

    Full Text Available The study was conducted to assess the effect of Hyacinth beans on the performance of broilers, for a period of 47 day feeding trial. In addition to basal control (A, another treatment diets were formulated to have Hyacinth beans at 15% (B, C without or with enzyme additives and 20% (D, E without or with enzyme additives. A total of 150 unsexed Ross 308 chicks were randomly distributed to 5 dietary treatments, with 5 replicates (6 birds per rep Feed and water were offered ad- libitum. Results illustrated that, feed intake (P ≤ 0.01, weight gain (P ≤ 0.01, FCR (P ≤ 0.05, PER (P ≤ 0.01 and dressing percentages (P ≤ 0.01 were negatively affected by Hyacinth beans inclusion levels (15%, 20%. Neither the processing method practiced for Hyacinth beans nor the enzyme additives were able to improve the performance of broilers better than or comparable to that of basal control broiler diet. The results as well revealed that, treatment diets of 15% Hyacinth beans displayed better performance than 20% level for all of the parameters measured including the dressing percentages and internal organs relative weight.

  8. Effect of phosphor addition on eutectic solidification and microstructure of an Al-13%Si alloy

    Liao Hengcheng

    2011-11-01

    Full Text Available As the refiner or modifier, the master alloys containing high concentration phosphor are widely used in preparing eutectic or hypereutectic Al-Si alloys. To study the effect of phosphor addition on the eutectic solidification and microstructure of the Al-13%Si alloy, an investigation has been undertaken by means of thermal analysis and micro/macro-structure observation. Results indicate that addition of phosphor in near eutectic Al-Si alloy promotes the nucleation of eutectic but has little refinement impact on primary Si particles as expected. Conversely, both primary Si particles and eutectic Si flakes become slightly coarser in P-rich alloys. The coarsening of eutectic Si flakes ties closely to the increased eutectic growth temperature with phosphor addition. The eutectic solidification of the alloy proceeds from the near mold zone towards the center, and it is also found that a few independent nucleation regions emerge in liquid at the solidification front due to the addition of phosphor.

  9. Clinical effect of driver mutations of JAK2, CALR, or MPL in primary myelofibrosis.

    Rumi, Elisa; Pietra, Daniela; Pascutto, Cristiana; Guglielmelli, Paola; Martínez-Trillos, Alejandra; Casetti, Ilaria; Colomer, Dolors; Pieri, Lisa; Pratcorona, Marta; Rotunno, Giada; Sant'Antonio, Emanuela; Bellini, Marta; Cavalloni, Chiara; Mannarelli, Carmela; Milanesi, Chiara; Boveri, Emanuela; Ferretti, Virginia; Astori, Cesare; Rosti, Vittorio; Cervantes, Francisco; Barosi, Giovanni; Vannucchi, Alessandro M; Cazzola, Mario

    2014-08-14

    We studied the impact of driver mutations of JAK2, CALR, (calreticulin gene) or MPL on clinical course, leukemic transformation, and survival of patients with primary myelofibrosis (PMF). Of the 617 subjects studied, 399 (64.7%) carried JAK2 (V617F), 140 (22.7%) had a CALR exon 9 indel, 25 (4.0%) carried an MPL (W515) mutation, and 53 (8.6%) had nonmutated JAK2, CALR, and MPL (so-called triple-negative PMF). Patients with CALR mutation had a lower risk of developing anemia, thrombocytopenia, and marked leukocytosis compared with other subtypes. They also had a lower risk of thrombosis compared with patients carrying JAK2 (V617F). At the opposite, triple-negative patients had higher incidence of leukemic transformation compared with either CALR-mutant or JAK2-mutant patients. Median overall survival was 17.7 years in CALR-mutant, 9.2 years in JAK2-mutant, 9.1 years in MPL-mutant, and 3.2 years in triple-negative patients. In multivariate analysis corrected for age, CALR-mutant patients had better overall survival than either JAK2-mutant or triple-negative patients. The impact of genetic lesions on survival was independent of current prognostic scoring systems. These observations indicate that driver mutations define distinct disease entities within PMF. Accounting for them is not only relevant to clinical decision-making, but should also be considered in designing clinical trials. PMID:24986690

  10. The Effect of Plants with Novel Traits (PNT) Regulation on Mutation Breeding in Canada

    The Canadian Environmental Protection Act (1988) has within it a definition for biotechnology. This definition would have allowed the government department, Environment Canada, to regulate all genetically modified organisms (GMOs) in Canada. In response to this, the Canadian Food Inspection Agency (CFIA), which reports to the Minister of Agriculture and Agri-Food Canada, developed the concept of a Plant with Novel Trait (PNT). Not only does this definition capture GMOs, it also includes induced mutations, natural mutations and exotic germplasm that have not previously been grown in Canada. It is a system that is product, not process based. However, apart from questions regarding the novelty of traits in new plant varieties, breeders are asked by CFIA to identify the process used to develop the trait or traits in question. Field trials involving breeding lines with a PNT may be subject to confined testing. This conference celebrated 80 years of unconfined development and testing of induced plant mutations. This regulation is time consuming, expensive and an innovation barrier for Canadian plant breeding. It can only be hoped that other nations, and particularly those that have successfully used induced mutations, will not emulate Canada's approach. (author)

  11. Effect of boron addition on hydrogen embrittlement sensitivity in Fe-Ni based alloys

    In Fe-Ni based alloys, hydrogen embrittlement sensitivity is thought to correlate well with microstructure. The effect of boron addition on microstructure of Fe-Ni austenitic alloys has been investigated. It is found that 0.002 wt.% boron addition can significantly retard the formation of η phase, and only a few continuous carbides precipitate at the grain boundaries. As the boron content increases to 0.006 wt.%, carbides at grain boundaries become discontinuous, and are finer in size than that in the alloy with 0.002 wt.% boron. Significant decrease of the percent loss of reduction of area (RA) are seen in the alloys with boron contents lower than 0.006 wt.%. However, when further increasing the boron concentration to 0.01 wt.%, an increase in the percent loss of RA is found, due to the re-appearance of η phase and boride precipitation. Appropriate addition of boron can be an effective way of lowering hydrogen embrittlement sensitivity in Fe-Ni based alloys.

  12. EFFECT OF MONTMORILLONITE ADDITION ON MECHANICAL CHARACTERIZATIONS OF POLYIMIDE NANOCOMPOSITE FILMS

    Wang Xishu; Zhang Yihe; Fu Shaoyun; Feng Xiqiao

    2005-01-01

    Tensile deformation and fracture characteristics of polyimide/montmorillonite nanocomposite films are investigated to enhance the particular mechanical properties and understand the effective factors in dominating the mechanical properties of nanocomposites, such as the nanolayer, matrix and nanolayer/matrix interface. How to contribute to the mechanical properties of nanocomposite film is a very complex problem. In this paper, these factors are analyzed based on the addition amount and fracture mechanics. The results indicate that the specimen at 20 wt% MMT breaks prematurely with a fracture strength (σb=78 MPa) much lower than that (σb = 128 MPa) at the 1wt% MMT. However, the Young's modulus (3.2 GPa) of the former is higher than that (1.9 GPa) of the latter. Fractography also indicates that the brittle cracking formed in high content addition is the main cause of failure but microscopically ductile fracture morphology still exists locally. And for the trace element addition, the smaller threading slipping veins are evenly distributed on the entire fracture section of these films. Therefore, these characteristics would presumably be associated with both the concentration effects of size of nanocomposite sheets and the increasing deformation harmony in nanolayers.

  13. Density functional theory study of the effects of alloying additions on sulfur adsorption on nickel surfaces

    Highlights: ► We study sulfur adsorption on metal doped and undoped Ni surfaces. ► Hybridization of Ni-3d and S-3p states plays the most important role in the formation of Ni-S bonds. ► Au, Ag, Al, Bi, Cd, Sb, Sn, Zn additions can significantly increase sulfur tolerance of Ni. ► Sn, Sb, and Bi alloying additions have the strongest effects on sulfur adsorption. - Abstract: Reactions of hydrogen sulfide (H2S) with Nickel/Ytrria-doped zirconia (Ni/YDZ) anode materials might cause degradation of the performance of solid oxide fuel cells when S containing fuels are used. In this paper, we employ density functional theory to investigate S adsorption on metal (M)-doped and undoped Ni(0 0 1) and Ni(1 1 1) surfaces. Based on the performed calculations, we analyze the effects of 12 alloying additions (Ag, Au, Al, Bi, Cd, Co, Cu, Fe, Sn, Sb, V, and Zn) on the temperature of transition between clean (S atoms do not adsorb on the surfaces) and contaminated (S atoms can adsorb on the surfaces spontaneously) M-doped Ni surfaces for different concentrations of H2S in the fuel. Predicted results are consistent with many experimental studies relevant to S poisoning of both Ni/YDZ and M-doped Ni/YDZ anode materials. This study is important to understand S poisoning phenomena and to develop new S tolerant anode materials.

  14. Individual and combined in vitro (anti)androgenic effects of certain food additives and cosmetic preservatives.

    Pop, Anca; Drugan, Tudor; Gutleb, Arno C; Lupu, Diana; Cherfan, Julien; Loghin, Felicia; Kiss, Béla

    2016-04-01

    The individual and combined (binary mixtures) (anti)androgenic effect of butylparaben (BuPB), butylated hydroxyanisole (BHA), butylated hydroxytoluene (BHT) and propyl gallate (PG) was evaluated using the MDA-kb2 cell line. Exposing these cells to AR agonists results in the expression of the reporter gene (encoding for luciferase) and luminescence can be measured in order to monitor the activity of the reporter protein. In case of the evaluation of the anti-androgenic effect, the individual test compounds or binary mixtures were tested in the presence of a fixed concentration of a strong AR agonist (1000 pM 5-alpha-dihydrotestosterone; DHT). Cell viability was assessed using a resazurin based assay. For PG, this is the first report in the literature concerning its (anti)androgenic activity. In case of both individual and mixture testing none of the compounds or binary combinations showed androgenic activity. When tested in the presence of DHT, BuPB, BHA and BHT proved to be weak anti-androgens and this was confirmed during the evaluation of binary mixtures (BuPB+BHA, BuPB+BHT and BHA+BHT). Besides performing the in vitro testing of the binary combinations, two mathematical models (dose addition and response addition) were evaluated in terms of accuracy of prediction of the anti-androgenic effect of the selected binary mixtures. The dose addition model guaranteed a good correlation between the experimental and predicted data. However, no estimation was possible in case of mixtures containing PG, due to the lack of effect of the compound in case of the individual testing. PMID:26812027

  15. Effect of calcium chloride addition on ice cream structure and quality.

    Costa, F F; Resende, J V; Abreu, L R; Goff, H D

    2008-06-01

    The influence of calcium fortification by the addition of calcium chloride on quality parameters of ice cream based on physical properties was investigated, as was the effect of kappa-carrageenan at modifying the effects of this calcium fortification. Four ice cream mixes of conventional composition, with added kappa-carrageenan (0 or 0.025%) and added calcium chloride (0 or 4.4 g L(-1) = 40 mM of added Ca(2+)), were prepared. Modulated temperature-differential scanning calorimetry was used to investigate the effect of calcium chloride on the nucleation temperature, enthalpy of melting, and freezing point depression. The protein composition of 15.4% (wt/wt) reconstituted skim milk powder solutions with or without 4.4 g L(-1) added CaCl(2) and in the supernatant after ultracentrifugation was determined. Fat particle size distributions in ice cream were characterized by light scattering. Ice crystal sizes before and after temperature cycling were determined by cold-stage light microscopy. The results demonstrated that the addition of calcium chloride led to a substantial increase in ice crystal sizes and in fat partial coalescence, which were exacerbated by the addition of kappa-carrageenan. These results can be explained by the interaction between Ca(2+) ions and casein micelles, rather than any effects on freezing point depression. The calcium ions led to a more compact micelle, less serum beta-casein, and high fat destabilization, all of which would be expected to reduce macromolecular structure and volume occupancy in the unfrozen phase, which led to increased rates of ice recrystallization. PMID:18487638

  16. Effect of boron and carbon addition on microstructure and mechanical properties of metastable beta titanium alloys

    Highlights: • Effect of boron and carbon on properties of three beta titanium alloys studied. • Ti–15V–3Cr–3Mo–3Sn, Ti–10V–2Fe–3Al, and Ti–5V–5Mo–5Al–3Cr alloys studied. • Hardness and 0.2% YS increases and elongation to failure deteriorates with the B and C addition. • Ageing in comparison to solution treatment results in increase in strength and decrease in elongation. • Low ‘n′ values and multiple slopes are observed in log–log plots of true stress–true strain curves. - Abstract: Effect of boron and carbon on microstructure and mechanical properties of β titanium alloys Ti–15V–3Cr–3Mo–3Sn, Ti–10V–2Fe–3Al, and Ti–5V–5Mo–5Al–3Cr has been studied in detail. The addition of boron and carbon results in refinement of β grain size and α-precipitates during ageing. While the hardness and tensile strength increase with the addition of boron and carbon, the elongation to failure deteriorates. The increase in strength is attributed to a synergistic effect of grain refinement and load sharing by TiB and TiC particles; whereas decrease in elongation is due to the brittleness of these hard particles. Ageing results in increase in strength and decrease in elongation as compared to solution treatment condition. In this case, the effect of boron and carbon is marginal. Further enhancement in the properties can be achieved by fine tuning heat treatment parameters. Multiple slopes are observed in log–log plots of true stress–true strain thereby implying different deformation mechanisms over a large range of plastic deformation

  17. Effect of acid additives on grafting efficiency and water absorption of hydrolyzed cassava starch grafted polymers

    Gelatinized cassava starch was radiation graft copolymerized with acrylamide, acrylic acid or their mixture in the presence of sulphuric acid or maleic acid. Various acid concentrations were used from 0.001 to 0.1 M of sulphuric acid while the maleic acid concentrations were varied from 1 to 3% (by weight). The optimum total dose and dose rate were investigated. The saponification temperature and time had the marked effects on grafting characteristics and water absorption capacity. We found that the effect of maleic acid addition gave a profound effect on water absorption. The CHNS/O analyses indicated significant changes in the nitrogen content in the hydrolyzed starch grafted polyacrylamide with 2% maleic acid. The article explains the possible causes for the enhancement influence of mineral acid and maleic acid on grafting behavior and water absorption of the saponified cassava starch grafted polyacrylamide super absorbent polymer. (author)

  18. Effect of lysine addition on growth of black iguana (Ctenosaura pectinata).

    Guzmán, Juan José Ortiz; Luis, Arcos-García José; Martínez, Germán D Mendoza; Pérez, Fernando Xicoténcatl Plata; Mascorro, Gisela Fuentes; Inzunza, Gabriela Ruelas

    2013-01-01

    The effects of the addition of lysine to commercial feed given to captive black iguana (Ctenosaura pectinata) were evaluated in terms of growth and feed digestibility. Twenty-eight-day-old black iguana with an initial weight of 5.5 ± 0.3 g were housed individually in cages measuring 45 × 45 × 45 cm. The experiment lasted 150 days. The ambient temperature ranged from 28 to 35°C with a relative humidity of 60 to 95%. Treatments consisted of the addition of different percentages of lysine to the feed (0.0, 0.1, 0.2, and 0.3%, dry matter [DM] base). There was a linear response (P iguana diet in the first months of life is important to stimulate growth and intake. PMID:22628251

  19. Effects of lanthanum addition on corrosion resistance of hot-dipped galvalume coating

    YANG Dong; CHEN Jianshe; HAN Qing; LIU Kuiren

    2009-01-01

    Effects of La addition on corrosion resistance of hot-dipped galvalume coating steel wire were investigated. The corrosion resistance of Zn-Al-Si-La alloy coatings containing 0, 0.02wt.%, 0.05wt.%, 0.1wt.% and 0.2wt.% La were evaluated by various tests such as copper-accelerated acetic acid salt spray testing (CASS), immersion test in 3.5% NaCl solution, electrochemical tests including weak polarization curves and electrochemical impedance spectroscopy (EIS) tests, scanning electron microscope (SEM) test and X-ray diffraction (XRD) test. It was found that the corrosion resistance of galvalume coating could be improved by adding proper amounts of La. Meanwhile, the mechanism of the improvement of corrosion resistance by La addition was discussed.

  20. Effects of additives on the stability of electrolytes for all-vanadium redox flow batteries

    The stability of the electrolytes for all-vanadium redox flow battery was investigated with ex-situ heating/cooling treatment and in-situ flow-battery testing methods. The effects of inorganic and organic additives have been studied. The additives containing the ions of potassium, phosphate, and polyphosphate are not suitable stabilizing agents because of their reactions with V(V) ions, forming precipitates of KVSO6 or VOPO4. Of the chemicals studied, polyacrylic acid and its mixture with CH3SO3H are the most promising stabilizing candidates which can stabilize all the four vanadium ions (V2+, V3+, VO2+, and VO2+) in electrolyte solutions up to 1.8 M. However, further effort is needed to obtain a stable electrolyte solution with >1.8 M V5+ at temperatures higher than 40 C.

  1. Effect of Additives on Magnetic Properties of High Frequency MnZn Power Ferrite

    YU Zhong; LAN Zhongwen; WANG Jingmei; ZHANG Yidong; WANG Haocai

    2004-01-01

    The effect of additives,such as CaO and V2O5 on the magnetic properties of high frequency MnZn power ferrite is studied by the conventional ceramic process.As a result,the grain boundary resistivity increases and the power loss declines with the addition of CaO enriched at the grain boundary.By adding an optimum amount of V2O5 which acts indirectly via liquid phase formation and influences the microstructural development during sintering,the crystalline grain of ferrite was refined,the porosity decreases,the amount of grain boundary and the grain boundary resistivity increased,so the power loss is suppressed.

  2. Effects of recrystallization and Nb additions on texture and mechanical anisotropy of Zircaloy

    Murty, K.L. (North Carolina State University, Raleigh, NC 27695-7909 (United States)); Jallepalli, Ravi (North Carolina State University, Raleigh, NC 27695-7909 (United States)); Mahmood, S.T. (North Carolina State University, Raleigh, NC 27695-7909 (United States))

    1994-06-01

    The effect of recrystallization on the crystallographic textures and anisotropic mechanical properties of Zircaloy-4 sheets was investigated. In addition, the influence of niobium additions on these properties was studied using three different alloys. The mechanical anisotropy parameters were determined by mechanical testing of gridded tensile samples. The textures were characterized by X-ray pole figure measurements and crystallite orientation distribution functions (CODFs). The CODFs were combined with a crystal plasticity model to predict the anisotropy parameters based on the dominance individually of basal, prism and pyramidal slip systems. Good agreement was noted between the experimental results and model predictions based on prism slip for the recrystallized materials, while the results on cold-worked sheets differed from model predictions for all the three slip systems. ((orig.))

  3. Effects of recrystallization and Nb additions on texture and mechanical anisotropy of Zircaloy

    The effect of recrystallization on the crystallographic textures and anisotropic mechanical properties of Zircaloy-4 sheets was investigated. In addition, the influence of niobium additions on these properties was studied using three different alloys. The mechanical anisotropy parameters were determined by mechanical testing of gridded tensile samples. The textures were characterized by X-ray pole figure measurements and crystallite orientation distribution functions (CODFs). The CODFs were combined with a crystal plasticity model to predict the anisotropy parameters based on the dominance individually of basal, prism and pyramidal slip systems. Good agreement was noted between the experimental results and model predictions based on prism slip for the recrystallized materials, while the results on cold-worked sheets differed from model predictions for all the three slip systems. ((orig.))

  4. Effect of Additive on Sulfur-fixation Process of Sulfur-fixation Agent

    XIE Jun-lin; QIU Jian-rong; ZHAO Gai-ju; LOU Jin-ping; HAN Chun-hua

    2003-01-01

    The crystallization behavior of desulfurization product is directly related to its high-temperatureresistant ability. Effects of the additive on the sulfur-fixation efficiency of the Ba-sulfur-fixation agent and also on the crystallization behavior of the sulfur-fixation product were studied when CaCO3 and BaCO3 were used as the desulfurization agent and MgO and SrCO3 used as the assistant sulfur-fixation agent. The result shows that increase of sulfur-fixation capability for the additive is not owe to their directly react to form sulfate or interact with CaCO3 and BaCO3 to form composite mineral heat-resistant in high temperature, but owe to their activation to sulfur-fixation reaction of the sulfur-fixation agent.

  5. The Effectiveness of the Additional Vocational Education and Staff Development for Industrial Enterprises

    Y. S. Kalabina

    2012-01-01

    Full Text Available In the course of the Russian economy modernization, developing the effec- tive system of vocational training and further professional training appears to be the main condition for the dynamic competitive advantage of industrial enterprises. The paper inves- tigates the urgent issue of developing the system of additional vocational training and staff development with the reference to the ever-changing institutional logic controlling the em- ployee – employer relations. The paper presents the review of theoretic approaches to the system of additional vocational training, as well as the economic analysis and estimates of return on investment in different forms of vocational training. The methodological approach to the system efficiency estimation is given along with the factors determining the forma- tion and development of vocational training system. Based on the research findings, the recommendations integrating the staff development policy are given aimed at promoting the effectiveness of the employee – employer relations. 

  6. Effects of phosphourus addition on the physical properties and surface condition of tungsten-copper composites

    Tungsten-copper composites containing a small amount of phosphorus prepared using conventional P/M method. Cu3P powder was used as phosphorous source. The effects of phosphorus addition on the physical properties and the surface condition were investigated and the existing form of phosphorus was specified on the tungsten-copper composites The results are summarized as follows. The tungsten-copper composite containing 10 % copper, for example, demonstrated optimum thermal conductivity at the phosphorus addition of 0.02 %. The density of the composites was almost 100 % and the surface of the sintered body was flat and smooth after sintering at a temperature between 1100 and 1150 oC. It was shown that phosphorus exists as Co2P. (author)

  7. Macro-economic effects of additional energy conservation in the European Community

    The aim of the title study is to evaluate the environmental and economic consequences of additional energy conservation in five Western European countries: the Netherlands, the Federal Republic of Germany, the United Kingdom, France and Italy. In the first part of the study the economic effects of a policy, in which additional energy conservation is realized only for the Netherlands, is calculated. In this report the results are presented. The calculated results of the economic effects of a coordinated energy conservation policy in the abovementioned countries will be published in a separate report. The effects of three policy variants will be evaluated: the non-financial policy variant, the shift of the financial burden variant, and the variant in which the levies are not compensated.The starting point for the first variant is an autonomous realization of the energy conservation. The basis of the second variant is that an equal amount of energy can be saved by means of a substantial energy levy. The profits of this levy can be used to reduce the financial burden of labour. For the economic calculations use has been made of the HERMES-model. Every member of the European Community has developed such a macro-economic model. In chapter two the different starting points for the calculations are outlined, with special attention to descriptions of the policy variants, the model-input and the basic projection. In chapter three the economic effects of the policy variants are presented and discussed. In chapter four the energy conservation and the environmental effects of the variants are dealt with. The most important conclusion of this study is that a considerable amount of energy can be saved, which will have positive effects on the economy and the environment. 8 figs., 20 tabs., 6 apps., 32 refs

  8. EFFECTS OF WATER TABLE AND NITROGEN ADDITION ON CO2 EMISSION FROM WETLAND SOIL

    YANG Ji-song; LIU Jing-shuang; YU Jun-bao; WANG Jin-da; QIN Sheng-jin; LI Xin-hua

    2005-01-01

    Soil respiration is a main dynamic process of carbon cycle in wetland. It is important to contribute to global climate changes. Water table and nutritious availability are significant impact factors to influence responses of CO2 emission from wetland soil to climate changes. Twenty-four wetland soil monoliths at 4 water-table positions and in 3 nitrogen status have been incubated to measure rates of CO2 emission from wetland soils in this study.Three static water-table controls and a fluctuant water-table control, with 3 nitrogen additions in every water-table control,were carried out. In no nitrogen addition treatment, high CO2 emissions were found at a static low water table ( Ⅰ )and a fluctuant water table (Ⅳ),averaging 306.7mg/(m2·h) and 307.89mg/(m2·h), respectively, which were 51%-57% higher than that at static high water table ( Ⅱ and Ⅲ). After nitrogen addition, however, highest CO2 emission was found at Ⅱ and lowest emission at Ⅲ. The results suggested that nutritious availability of wetland soil might be important to influence the effect of water table on the CO2 emission from the wetland soil. Nitrogen addition led to enhancing CO2 emissions from wetland soil, while the highest emission was found in 1N treatments other than in 2N treatments. In 3 nutritious treatments,low CO2 emissions at high water tables and high CO2 emissions at low water tables were also observed when water table fluctuated. Our results suggested that both water table changes and nutritious imports would effect the CO2 emission from wetland.

  9. Genome Destabilizing Mutator Alleles Drive Specific Mutational Trajectories in Saccharomyces cerevisiae

    Stirling, Peter C.; Shen, Yaoqing; Corbett, Richard; Jones, Steven J. M.; Hieter, Philip

    2014-01-01

    In addition to environmental factors and intrinsic variations in base substitution rates, specific genome-destabilizing mutations can shape the mutational trajectory of genomes. How specific alleles influence the nature and position of accumulated mutations in a genomic context is largely unknown. Understanding the impact of genome-destabilizing alleles is particularly relevant to cancer genomes where biased mutational signatures are identifiable. We first created a more complete picture of cellular pathways that impact mutation rate using a primary screen to identify essential Saccharomyces cerevisiae gene mutations that cause mutator phenotypes. Drawing primarily on new alleles identified in this resource, we measure the impact of diverse mutator alleles on mutation patterns directly by whole-genome sequencing of 68 mutation-accumulation strains derived from wild-type and 11 parental mutator genotypes. The accumulated mutations differ across mutator strains, displaying base-substitution biases, allele-specific mutation hotspots, and break-associated mutation clustering. For example, in mutants of POLα and the Cdc13–Stn1–Ten1 complex, we find a distinct subtelomeric bias for mutations that we show is independent of the target sequence. Together our data suggest that specific genome-instability mutations are sufficient to drive discrete mutational signatures, some of which share properties with mutation patterns seen in tumors. Thus, in a population of cells, genome-instability mutations could influence clonal evolution by establishing discrete mutational trajectories for genomes. PMID:24336748

  10. EFFECT OF MODE OF ADDITION OF DISINTEGRANTS ON DISSOLUTION OF MODEL DRUG FROM WET GRANULATION TABLETS

    Md. Mofizur Rahman

    2011-02-01

    Full Text Available The purpose of the study was to formulate immediate release tablets using various types of disintegrants (crospovidone, sodium starch glycolate and sodium carboxymethylcellulose, in order to investigate the effect of mode of incorporation of disintegrants on release mechanism from tablets. Acetaminophen, a poor soluble drug was used as a model drug to evaluate its release characteristics from different formulations. The USP paddle method was selected to perform the dissolution profiles carried out by USP apparatus 2 (paddle at 50 rpm in 900 ml phosphate buffer pH 5.8. Successive dissolution time, time required for 25%, 50% and 80% of the drug release (T25%, T50%, T80% was used to compare the dissolution results. A One way analysis of variance (ANOVA was used to interpret the result. tatistically significant differences were found among the drug release profile from all the formulations except mode of addition of crosspovidone. At a fixed amount of disintegrants, extragranular mode of addition seemed to be the best mode of incorporation. The best release was achieved with the crospovidone containing formulations. The T50 and T80 values were indicative of the fact that the drug release was faster from tablet formulations containing crosspovidone. The drug release was very much negligible difference by the mode of crospovidone addition. Two formulations found very small T50 and T80values indicating very much faster release. From the all formulations corresponded extragranular mode of addition could be the best mode of incorporation. The drug release was unaffected by the mode of crospovidone addition. The mode of incorporation of disintegrants suggested enchancing the release of poor soluble drugs.

  11. Thermodynamic Effect of Platinum Addition to beta-NiAl: An Initial Investigation

    2005-01-01

    An initial investigation was conducted to determine the effect of platinum addition on the activities of aluminum and nickel in beta-NiAl(Pt) over the temperature range 1354 to 1692 K. These measurements were made with a multiple effusion-cell configured mass spectrometer (multi-cell KEMS). The results of this study show that Pt additions act to decreased alpha(Al) and increased the alpha(Ni) in beta-NiAl(Pt) for constant X(sub Ni)/X(sub Al) approx. = 1.13, while at constant X(sub Al) the affect of Pt on Al is greatly reduced. The measured partial enthalpies of mixing indicate Al-atoms have a strong self interaction while Ni- and Pt-atoms in have similar interactions with Al-atoms. Conversely the binding of Ni-atoms in beta-NiAl decreases with Pt addition independent of Al concentration. These initial results prove the technique can be applied to the Ni-Al-Pt system but more activity measurements are required to fully understand the thermodynamics of this system and how Pt additions improved the scaling behavior of nickel-based superalloys. In addition, with the choice of a suitable oxide material for the effusion-cell, the "closed" isothermal nature of the effusion-cell allows the direct investigation of an alloy-oxide equilibrium which resembles the "local-equilibrium" description of the metal-scale interface observed during high temperature oxidation. It is proposed that with an Al(l) + Al2O3(s) experimental reference state together with the route measurement of the relative partial-pressures of Al(g) and Al2O(g) allows the activities of O and Al2O3 to be determined along with the activities of Ni and Al. These measurements provide a direct method of investigating the thermodynamics of the metal-scale interface of a TGO-scale.

  12. Spatial interpolation of hourly rainfall – effect of additional information, variogram inference and storm properties

    A. Verworn

    2010-08-01

    Full Text Available Hydrological modelling of floods relies on precipitation data with a high resolution in space and time. A reliable spatial representation of short time step rainfall is often difficult to achieve due to a low network density. In this study hourly precipitation was spatially interpolated with the multivariate geostatistical method kriging with external drift (KED using additional information from topography, rainfall data from the denser daily networks and weather radar data. Investigations were carried out for several flood events in the time period between 2000 and 2005 caused by different meteorological conditions. The 125 km radius around the radar station Ummendorf in northern Germany covered the overall study region. One objective was to assess the effect of different approaches for estimation of semivariograms on the interpolation performance of short time step rainfall. Another objective was the refined application of the method kriging with external drift. Special attention was not only given to find the most relevant additional information, but also to combine the additional information in the best possible way. A multi-step interpolation procedure was applied to better consider sub-regions without rainfall.

    The impact of different semivariogram types on the interpolation performance was low. While it varied over the events, an averaged semivariogram was sufficient overall. Weather radar data were the most valuable additional information for KED for convective summer events. For interpolation of stratiform winter events using daily rainfall as additional information was sufficient. The application of the multi-step procedure significantly helped to improve the representation of fractional precipitation coverage.

  13. Effect of zirconium addition on the recrystallization behaviour of a commercial Al–Cu–Mg alloy

    K T Kashyap

    2001-12-01

    It is well known that the second phase particles have an effect on recrystallization and grain growth behaviour of an alloy. Particularly the bimodal distribution of second phase particles has an effect which is opposite in sense where coarse second phase particles (> 1 m) stimulate nucleation while fine particles exhibit Zener drag. In the literature, the effect of zirconium addition to aluminium alloys has been well documented in order to produce superplasticity by giving ultra fine grain size to the alloy. Addition of zirconium produces Al3Zr particles which pin the grain boundaries during recrystallization and grain growth. In the present work, zirconium was added to a commercial Al–Cu–Mg alloy and by heat treatment Al3Zr particles were precipitated and after forging, the grain size was an order of magnitude lower than the alloy without zirconium. Transmission electron microscopy was employed to characterize the second phase particles, i.e. Al3Zr particles and found to be rod shaped and identified to be cubic ordered 12 phase with a lattice parameter of 0.408 nm. Further, it was observed that fine (100 nm) Al3Zr particles promote only continuous recrystallization which is polygonization of subgrains and subgrain growth. It was found that the fine dispersion of Al3Zr particles inhibits both recrystallization and grain growth in the commercial Al–Cu–Mg alloy.

  14. Stability of amorphous pharmaceutical solids: crystal growth mechanisms and effect of polymer additives.

    Sun, Ye; Zhu, Lei; Wu, Tian; Cai, Ting; Gunn, Erica M; Yu, Lian

    2012-09-01

    We review recent progress toward understanding and enhancing the stability of amorphous pharmaceutical solids against crystallization. As organic liquids are cooled to become glasses, fast modes of crystal growth can emerge. One such growth mode, the glass-to-crystal or GC mode, occurs in the bulk, and another exists at the free surface, both leading to crystal growth much faster than predicted by theories that assume diffusion defines the kinetic barrier of crystallization. These phenomena have received different explanations, and we propose that GC growth is a solid-state transformation enabled by local mobility in glasses and that fast surface crystal growth is facilitated by surface molecular mobility. In the second part, we review recent findings concerning the effect of polymer additives on crystallization in organic glasses. Low-concentration polymer additives can strongly inhibit crystal growth in the bulk of organic glasses, while having weaker effect on surface crystal growth. Ultra-thin polymer coatings can inhibit surface crystallization. Recent work has shown the importance of molecular weight for crystallization inhibitors of organic glasses, besides "direct intermolecular interactions" such as hydrogen bonding. Relative to polyvinylpyrrolidone, the VP dimer is far less effective in inhibiting crystal growth in amorphous nifedipine. Further work is suggested for better understanding of crystallization of amorphous organic solids and the prediction of their stability. PMID:22434258

  15. Effect of samarium addition and annealing on the properties of electrodeposited ceria thin films

    Zivkovic, L. [Laboratoire d' Electrochimie, Chimie des Interfaces et Modelisation pour l' Energie, LECIME, CNRS UMR 7575, Chimie ParisTech (ENSCP)-Paris, 11 rue Pierre et Marie Curie, 75231 Paris cedex 05 (France); The Vinca Institute of Nuclear Sciences, University of Belgrade, 11 001 Belgrade, PO BOX 522 (Serbia); Lair, V., E-mail: virginie-lair@ens.chimie-paristech.f [Laboratoire d' Electrochimie, Chimie des Interfaces et Modelisation pour l' Energie, LECIME, CNRS UMR 7575, Chimie ParisTech (ENSCP)-Paris, 11 rue Pierre et Marie Curie, 75231 Paris cedex 05 (France); Lupan, O. [Laboratoire d' Electrochimie, Chimie des Interfaces et Modelisation pour l' Energie, LECIME, CNRS UMR 7575, Chimie ParisTech (ENSCP)-Paris, 11 rue Pierre et Marie Curie, 75231 Paris cedex 05 (France); Department of Microelectronics and Semiconductor Devices, Technical University of Moldova, 168 Stefan cel Mare Blvd., Chisinau, MD-2004 (Moldova, Republic of); Ringuede, A. [Laboratoire d' Electrochimie, Chimie des Interfaces et Modelisation pour l' Energie, LECIME, CNRS UMR 7575, Chimie ParisTech (ENSCP)-Paris, 11 rue Pierre et Marie Curie, 75231 Paris cedex 05 (France)

    2011-03-31

    Samarium (Sm)-doped ceria (CeO{sub 2}) (SDC) is a promising material for high temperature electrochemical devices. Our work demonstrates that thin SDC films can be prepared by a cost-effective electrodeposition method at a low-temperature (30 {sup o}C) and - 0.8 V/SCE (saturated calomel electrode) potential. Analysis of the structural properties of the obtained SDC films, as-grown and annealed at 600 {sup o}C, has been carried out by X-ray diffraction (XRD). Morphology and film composition were studied using scanning electronic microscopy and energy dispersive X-ray analysis. Vibrational properties were determined by Raman spectroscopy. The effects of samarium addition into the deposition bath on the final film composition have been studied. According to XRD results, film crystallographic properties are directly linked to the percentage of Sm incorporated in the CeO{sub 2} lattice. We report on the electrochemical deposition of the SDC films performed over a large range of Sm additions (0-30%). The effect of temperature annealing has been studied as well.

  16. Effect of additives and steaming on quality of air dried noodles.

    Gatade, Abhijeet Arun; Sahoo, Akshaya Kumar

    2015-12-01

    Texture is the most important property for consumer acceptance in cooked noodles. The air dried noodles are known to have higher cooking loss and cooking time, to that of instant fried noodles. But the fat content of instant fried noodles is more. In the present work attempts were made to optimize the moisture content so as to obtain a smooth dough for extruded noodle preparation and develop air dried noodles of low fat content with lesser cooking loss and cooking time. To meet the objectives, the effect of various additives and steaming treatment on cooking quality, sensory attributes, textural properties and microstructure of noodles were studied. Dough prepared by addition of 40 ml water to 100 g flour resulted into formation of a soft dough, leading to production of noodles of improved surface smoothness and maximum yield. The use of additives (5 g oil, 0.2 g guar gum, 2 g gluten and 1 ml of 1 % kansui solution for 100 g of flour) and steaming treatment showed significant effect on noodles quality, with respect to cooking characteristics, sensory attributes and textural properties. The microstructure images justified the positive correlation between the effects of ingredients with steaming and quality parameters of noodles. Air dried noodles with reduced cooking loss (~50 % reduction) with marginal reduction in cooking time was developed, which were having similar characteristics to that of instant fried noodles. Compared to the instant fried noodle, the prepared air dried noodle was having substantially reduced fat content (~70 % reduction). Thus the present study will be useful for guiding extrusion processes for production of air dried noodles having less cooking time and low fat content. PMID:26604421

  17. Effect of Crumb Rubber and Warm Mix Additives on Asphalt Aging, Rheological, and Failure Properties

    Agrawal, Prashant

    Asphalt-rubber mixtures have been shown to have useful properties with respect to distresses observed in asphalt concrete pavements. The most notable change in properties is a large increase in viscosity and improved low-temperature cracking resistance. Warm mix additives can lower production and compaction temperatures. Lower temperatures reduce harmful emissions and lower energy consumption, and thus provide environmental benefits and cut costs. In this study, the effects of crumb rubber modification on various asphalts such as California Valley, Boscan, Alaska North Slope, Laguna and Cold Lake were also studied. The materials used for warm mix modification were obtained from various commercial sources. The RAF binder was produced by Imperial Oil in their Nanticoke, Ontario, refinery on Lake Erie. A second commercial PG 52-34 (hereafter denoted as NER) was obtained/sampled during the construction of a northern Ontario MTO contract. Some regular tests such as Dynamic Shear Rheometer (DSR) and Bending Beam Rheometer (BBR), Multiple Stress Creep Recovery (MSCR) and some modified new protocols such as the extended BBR test (LS-308) and the Double-Edge Notched Tension (DENT) test (LS-299) are used to study, the effect of warm mix and a host of other additives on rheological, aging and failure properties. A comparison in the properties of RAF and NER asphalts has also been made as RAF is good quality asphalt and NER is bad quality asphalt. From the studies the effect of additives on chemical and physical hardening tendencies was found to be significant. The asphalt samples tested in this study showed a range of tendencies for chemical and physical hardening.

  18. Likely Additive Ergogenic Effects of Combined Preexercise Dietary Nitrate and Caffeine Ingestion in Trained Cyclists

    Handzlik, Michal K.; Gleeson, Michael

    2013-01-01

    Aims. To evaluate the possible additive effects of beetroot juice plus caffeine on exercise performance. Methods. In a randomized, double-blinded study design, fourteen healthy well-trained men aged 22 ± 3 years performed four trials on different occasions following preexercise ingestion of placebo (PLA), PLA plus 5 mg/kg caffeine (PLA+C), beetroot juice providing 8 mmol of nitrate (BR), and beetroot juice plus caffeine (BR+C). Participants cycled at 60% maximal oxygen uptake ( V ˙ O 2 max) f...

  19. Effect of titanium addition on fracture toughness behavior of ZL108 alloy

    WENG Yong-gang; LI Zi-jing; LIU Zhi-yong; LIU Wen-cai; WANG Ming-xing; SONG Tian-fu

    2006-01-01

    Two different titanium alloying methods were applied to ZL108 alloy for preparing specimens containing titanium. The specimens were tested on the MTS 810 material test system for studying their behavior of the plane strain fracture toughness KIC. The experimental data were analyzed by the statistical significance tests. The results show that the fracture toughness of the ZL108 alloy containing titanium is superior to that of common ZL108 alloy containing no titanium, but there is no significant difference for different titanium alloying methods. Therefore titanium addition is an effective method for improving the fracture toughness of the alloy ZL108.

  20. Effect Of The Gadolinium Oxide Addition On The Electrical Properties Of Tetragonal Zirconium Dioxide

    Cyran J.; Wyrwa J.; Drożdż E.; Dziubaniuk M.; Rękas M.

    2015-01-01

    The aim of this work was examination of gadolinium-doped 3YSZ electrical and structural properties. Such materials may be used as electrolytes in intermediate temperature solid oxide fuel cells (IT-SOFC). First step of the research was synthesis of 3YSZ with different contents of gadolinium (0.25; 0.5; 1.0 at %). Prepared materials were characterized by high porosity. No effect of gadolinium addition on grain size was observed. The experimentally determined values of grain interiors electrica...

  1. Effect of addition of different hydrocolloids on pasting, thermal, and rheological properties of cassava starch

    Tatiana Dias Leite; Joel Fernando Nicoleti; Ana Lúcia Barretto Penna; Célia Maria Landi Franco

    2012-01-01

    Starches and gums are hydrocolloids frequently used in food systems to provide proper texture, moisture, and water mobility. Starch-gum interaction in food systems can change the starch granule swelling and its gelatinization and rheological properties. In this study, the effect of the addition of xanthan gum (XG), sodium carboxymethyl cellulose (SCMC), and carrageenan (CAR) at the concentrations of the 0.15, 0.25, 0.35 and 0.45% (w/v) on the pasting, thermal, and rheological properties of ca...

  2. Effects of Additive on the Mechanical Properties of Bamboo/pbs Composites

    Lee, Yeon-Hee; Yoon, Han-Ki; Takagi, Hitoshi; Ohkita, Kazuya

    Compared with general composites which are produced from fossil fuel, biodegradable resins have received considerable attention as an environment-friendly material. Bamboo fiber has relatively high strength compared with other natural fibers. Therefore, the focus of this study is to produce bamboo fiber reinforced Poly butylene succinate (PBS) composites by injection molding and to study the effects of additive on mechanical properties of this bamboo/PBS composite. The injection-molding is a highly productive fabrication technique. Bamboo/PBS composites were examined by flexural test and Vickers hardness. Also we examined fracture surface and microstructure of the bamboo/PBS composites by microscope.

  3. Thermodynamic network model for predicting effects of substrate addition and other perturbations on subsurface microbial communities

    Jack Istok; Melora Park; James McKinley; Chongxuan Liu; Lee Krumholz; Anne Spain; Aaron Peacock; Brett Baldwin

    2007-04-19

    The overall goal of this project is to develop and test a thermodynamic network model for predicting the effects of substrate additions and environmental perturbations on microbial growth, community composition and system geochemistry. The hypothesis is that a thermodynamic analysis of the energy-yielding growth reactions performed by defined groups of microorganisms can be used to make quantitative and testable predictions of the change in microbial community composition that will occur when a substrate is added to the subsurface or when environmental conditions change.

  4. Cellular and systemic effects of Parkinson’s disease-related LRRK2 mutations: An investigation of cytoskeletal function and the innate immune system in transgenic mice and human LRRK2 mutation carriers

    Caesar, Mareike

    2016-01-01

    Parkinson’s disease (PD) is, after Alzheimer’s disease, the most common neurodegenerative disorder. Mutations in the leucine rich repeat kinase 2 (LRRK2) are the most common known cause of familial PD but also constitute about 3.5 % of all sporadic PD cases. This work focuses on the effects of LRRK2 mutations on cytoskeletal function and on the innate immune system. Findings from animal models were translated to human material to assess their relevance in human disease states. Changes in ...

  5. Production of β-cyclodextrin: Effect of pH, time and additives

    Wadetwar Rita

    2006-01-01

    Full Text Available In the present paper attempt was made to produce an excipient, β-cyclodextrin from starch by the action of an enzyme cyclodextrin glucosyl transferase. The microbial strain utilized was Bacillus circulans because of its specificity for production of β-cyclodextrin. First the culture was grown under controlled conditions to obtain an enzyme cyclodextrin glucosyl transferase which was isolated and purified. The crude enzyme was employed for bioconversion of starch to β-cyclodextrin. Some parameters like incubation pH, incubation and fermentation time and effect of certain additives like polyethylene glycol and calcium chloride added during incubation were studied to optimize its yield. The maximum yield of cyclodextrin glucosyl transferase was after 36 h of fermentation. β-cyclodextrin yield was found to increase with the increase in incubation period, by the addition of polyethylene glycol 200, polyethylene glycol 400 and at pH 6. The activity and stability of enzyme was found to increase by addition of calcium chloride.

  6. Effects of He-3 addition on implosion of deuterium-tritium capsules on OMEGA

    E. K. Miller, et al.

    2008-03-01

    Glass (SiGDP) capsules were imploded on the OMEGA laser to look for anomalous degradation in yield (i.e., beyond what is predicted) with 3He addition similar to the “factor of two” degradation previously reported by MIT (Rygg et al., Phys. Plasmas 13, 2006) at a 50% 3He atom fraction. We did not see a significant anomalous degradation. The cause of the “Rygg” anomaly is as of yet unexplained, but differences in gas mixture (D-T vs. D2) or shell parameters (glass vs. plastic, diameter and wall thickness) may be responsible for the absence of this anomaly in the recent data. In addition, a short laser pulse (600 ps) was used to temporally separate shock and compression yield components in order to investigate mix. Previously, anomalously low compression yield had been observed when imploding glass targets containing 10 atm D-T with 10 kJ of laser. This effect was not seen in the recent data with 5 atm D-T and 15 kJ and the resulting γ and n burn histories were in good qualitative agreement with predictions for 3He addition.

  7. Effect of reinforcement nanoparticles addition on mechanical properties of SBS/curaua fiber composites

    Borba, Patricia M. [Servico Nacional de Aprendizagem Industrial (CETEPO/SENAI/RS), Sao Leopoldo, RS (Brazil). Centro Tecnologico de Polimeros; Tedesco, Adriana [Braskem S. A., III Polo Petroquimico, Triunfo, RS (Brazil); Lenz, Denise M., E-mail: denise.lenz@gmail.com [Universidade Luterana do Brasil (ULBRA), Canoas, RS (Brazil). Programa de Pos-graduacao em Engenharia de Materiais e Processos Sustentaveis

    2014-03-15

    Composites of styrene-butadiene-styrene triblock copolymer (SBS) matrix with curauá fiber and/or a nanoparticulated mineral (montmorillonite clay - MMT) used as reinforcing agents were prepared by melt-mixing. The influence of clay addition on properties like tensile and tear strength, rebound resilience, flex fatigue life, abrasion loss, hardness and water absorption of composites with 5, 10 and 20 wt% of curauá fiber was evaluated in presence of maleic anhydride grafted styrene-(ethylene-co-butylene)-styrene triblock copolymer (MA-g-SEBS) coupling agent. Furthermore, the effect of mineral plasticizer loading on tensile strength of selected composites was investigated. The hybrid SBS composite that showed the best overall mechanical performance was composed by 2 wt% of MMT and 5 wt% of curauá fiber. Increasing fiber content up to 20 wt% resulted in a general decrease in all mechanical properties as well as incorporation of 5 wt% MMT caused a decrease in the tensile strength in all fiber contents. The hybrid composites showed clay agglomerates (tactoids) poorly dispersed that could explain the poor mechanical performance of composites at higher concentrations of curauá fiber and MMT nanoparticles. The addition of plasticizer further decreased the tensile strength while the addition of MMT nanoparticles decreased water absorption for all SBS composites. (author)

  8. Synergistic Effect of Selenium Addition and Water Stress on Melilotus officinalis L. Mineral Content

    Panagiota KOSTOPOULOU

    2015-12-01

    Full Text Available The objective of this study was to examine the combined effects of selenium (Se enrichment and water stress on the accumulation of available macro- and micronutrients in Melilotus officinalis L. aerial parts. Plants of M. officinalis were subjected to three levels of Se addition (0, 1 and 3 mg Se L-1 water and to two water treatments: a full irrigation and b limited irrigation (water stress. The above ground biomass (stems and leaves was analyzed for Se, potassium (K, sodium (Na, magnesium (Mg, iron (Fe, copper (Cu, calcium (Ca, manganese (Mn and zinc (Zn. Se addition differentially affected the K, Mg and Ca content of M. officinalis aerial parts, while it led to the reduction of the micronutrients Cu, Fe and Mn. Water stress resulted in the increase of K, Na, Mg, Ca and Cu, and to the decrease of the Fe, Zn and Mn content. An interaction between selenium addition and water treatment was more notable for Ca and Mg, which decreased under water stress at low Se level and for Zn and Cu, which increased under water stress at high Se level. According to our findings, Se-induced increased accumulation of some inorganic ions in the aerial parts of this species under water stress conditions could serve as a means to alleviate the adverse impact of water deficit on important metabolic processes, enhancing M. officinalis tolerance to water stress.

  9. Effects of Mo and Al addition on the Mechanical Properties of 15Cr ODS steel

    Shim, Jaewon; Noh, Sanghoon; Kang, Sukhoon; Chun, Youngbum; Choi, Byoungkwon; Han, Changhee; Kim, Taekyu [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2013-05-15

    Oxide particle controls the strength of the ODS steel and the addition of Mo, W, and Al, which changes the microstructures and remarkably influences the strength of ODS steel. In this study, Fe-based ODS alloys with Mo, W, and Al additions were fabricated by HIP and hot rolling processes, and their microstructures and mechanical properties were investigated. Some Fe-based ODS alloys were fabricated by a HIP process, and their microstructures and mechanical properties were investigated. Mo, W, and Al are considered to be very effective alloying elements for high strength and formability in Fe-based ODS alloys. As a result of a microstructure observation, grain refinement occurred in the case of the addition of W and Mo. However, the grain size and oxide particles of Fe-15Cr-ODS alloy Al added became coarse. Therefore, the hardness and tensile strength were decreased. On the other hand, the elongation was increased owing to the coarser grain. These preliminary results will be useful for developing advanced Fe-15Cr ODS alloy. The structural components for nuclear systems need to have formability as well as strength.

  10. Effect of Fruit Pomace Addition on Shortbread Cookies to Improve Their Physical and Nutritional Values.

    Tańska, Małgorzata; Roszkowska, Beata; Czaplicki, Sylwester; Borowska, Eulalia Julitta; Bojarska, Justyna; Dąbrowska, Aneta

    2016-09-01

    Fruit pomace remaining after juice extraction is still a source of bioactive compounds. Especially rich in these compounds is the pomace from blackcurrant fruit and from fruits of little-known horticultural plants, like: rowan, rosehip and elderberry. The addition of fruit pomace to bakery and confectionery products, especially to those made of white flour, may significantly enrich their composition with dietary fiber, vitamins and phenolic compounds. This study was aimed at determining the effect of 20 % addition of fruit pomace from rosehip, rowan, blackcurrant and elderberry on the properties of shortbread cookies. The pomace-containing cookies, compared to those without additives, were characterized by a darker color with a higher contribution of yellowness, and by higher hardness. The overall organoleptic assessment was comparable for all types of cookies, however the cookies with pomace were characterized by more perceptible taste and aroma, and were sourer. The extracts from pomace-supplemented cookies had a significantly stronger antioxidant capacity than that from the cookies without pomace, but they were ineffective in inhibiting lipid oxidation. The study showed that fruit pomace could improve the nutritional value of shortbread cookies. Furthermore, non-typical color of such a new product may be attractive to consumers. PMID:27319014

  11. The effectiveness of Additional Literacy Support (ALS) in Years 3 and 4.

    Bunn, Tim

    2008-08-01

    This study compared the progress in reading and spelling of 256 children in 11 classes in 9 English primary schools in Years 3 and 4, and a partially overlapping sample of 126 children who received additional help with literacy during 1 year. Teachers and teaching assistants used either Additional Literacy Support (ALS), a highly structured set of small group teaching materials devised by the English National Literacy Strategy, or a wide variety of other materials including other published intervention programmes, reading scheme-based, computer-based and individually designed interventions, or a combination of ALS and other interventions. The influence of a broad range of contextual factors were investigated, especially whether children's qualities, school factors such as socio-economic status and class size, and delivery differences made significant differences to the outcomes of the different interventions. The study used a naturalistic quasi-experimental design, in which teachers were asked to record details of their children and interventions without altering their professional decisions, which has not been used before in investigating literacy difficulties in context. ALS was marginally more effective than other interventions in the majority of classes, but was clearly superior in value for money terms. Children's qualities did not appear to affect outcomes. Although children receiving additional help made better than average progress, overall catch-up was limited, especially in spelling. PMID:18697191

  12. Effect of Co addition on the critical current density of MgB{sub 2} superconductor

    Kirat, G.; Kizilaslan, O.; Aksan, M.A., E-mail: mehmet.aksan@inonu.edu.tr; Yakinci, M.E.

    2014-07-15

    In this study, the (MgB{sub 2}){sub 1−x}Co{sub x} samples, where x=0.0, 0.1, 0.3, 0.6 and 0.8, were prepared by using the solid-state reaction technique. Effect of the Co-addition on the structural, magnetic, critical current density, J{sub c}, and flux pinning properties of the superconducting MgB{sub 2} system was investigated. A magnetic transition was observed with increasing the Co-concentration in MgB{sub 2}. For the pure MgB{sub 2}, J{sub c} was obtained to be 2.78×10{sup 4} A cm{sup −2} at 5 K and 1.7 kOe, but J{sub c} was suppressed by addition of Co to the system. It was found that a large amount of Co in MgB{sub 2} did not act as pinning centers which improves J{sub c}. The magnetic behavior observed by the Co-addition originates from the magnetic properties of cobalt itself.

  13. Effect of Probiotic Addition in Drinking Water on Body Weight and Body Measurements of Broiler Chickens

    Cyril Hrnčár

    2014-11-01

    Full Text Available The aim of this study was todetermine the effects of probiotic addition in drinking water on body weightand body measurements of broiler chickens. The experiment was carried out inhalf-operation conditions experimental base of Department of Poultry Science and Small Animal Husbandry of SlovakUniversity of Agriculture in Nitra in three-floor cage system. A total of 180 one day old chickens (Ross 308 wererandomly divided to 3 groups: experimental chickens of E1 group received a probiotic in drinking waterwith concentration of 1x109 colony forming units (CFU of Lactobacillus fermentum CCM 7158 in 1 g of nutrient medium andexperimental, chickens of E2 group concentration of 2x109 CFU of Enterococcus faecium M 74 in 1 g of nutrientmedium. The control group of chickens received drinking water without anyadditives. The fattening period lasted 42 days. Data of body weight and bodymeasurements (body length, bodycircumference, keel length, thigh length, and shank length were recording atages in 42day. The results of this study showed that body weight wassignificantly affected (P<0.05 by addition ofprobiotic strains Lactobacillus fermentum andEnterococcus faecium, betweenexperimental groups we found statistically not significant difference(P>0.05. The body measurements was not significantly affected (P>0.05by addition of probiotic in drinking water.

  14. Oil-Soluble Polymer Brush Grafted Nanoparticles as Effective Lubricant Additives for Friction and Wear Reduction.

    Wright, Roger A E; Wang, Kewei; Qu, Jun; Zhao, Bin

    2016-07-18

    The development of high performance lubricants has been driven by increasingly growing industrial demands and environmental concerns. Herein, we demonstrate oil-soluble polymer brush-grafted inorganic nanoparticles (hairy NPs) as highly effective lubricant additives for friction and wear reduction. A series of oil-miscible poly(lauryl methacrylate) brush-grafted silica and titania NPs were synthesized by surface-initiated atom transfer radical polymerization. These hairy NPs showed exceptional stability in poly(alphaolefin) (PAO) base oil; no change in transparency was observed after being kept at -20, 22, and 100 °C for ≥55 days. High-contact stress ball-on-flat reciprocating sliding tribological tests at 100 °C showed that addition of 1 wt % of hairy NPs into PAO led to significant reductions in coefficient of friction (up to ≈40 %) and wear volume (up to ≈90 %). The excellent lubricating properties of hairy NPs were further elucidated by the characterization of the tribofilm formed on the flat. These hairy NPs represent a new type of lubricating oil additives with high efficiency in friction and wear reduction. PMID:27265613

  15. Effect of reinforcement nanoparticles addition on mechanical properties of SBS/curaua fiber composites

    Composites of styrene-butadiene-styrene triblock copolymer (SBS) matrix with curauá fiber and/or a nanoparticulated mineral (montmorillonite clay - MMT) used as reinforcing agents were prepared by melt-mixing. The influence of clay addition on properties like tensile and tear strength, rebound resilience, flex fatigue life, abrasion loss, hardness and water absorption of composites with 5, 10 and 20 wt% of curauá fiber was evaluated in presence of maleic anhydride grafted styrene-(ethylene-co-butylene)-styrene triblock copolymer (MA-g-SEBS) coupling agent. Furthermore, the effect of mineral plasticizer loading on tensile strength of selected composites was investigated. The hybrid SBS composite that showed the best overall mechanical performance was composed by 2 wt% of MMT and 5 wt% of curauá fiber. Increasing fiber content up to 20 wt% resulted in a general decrease in all mechanical properties as well as incorporation of 5 wt% MMT caused a decrease in the tensile strength in all fiber contents. The hybrid composites showed clay agglomerates (tactoids) poorly dispersed that could explain the poor mechanical performance of composites at higher concentrations of curauá fiber and MMT nanoparticles. The addition of plasticizer further decreased the tensile strength while the addition of MMT nanoparticles decreased water absorption for all SBS composites. (author)

  16. Effect of radon and its progeny on the expression and mutation of p53 in lung tissues of mice

    Objective: To explore the effect of radon and its progeny on the expression and mutations of p53 in lung tissue of mouse model. Methods: Apoptosis was detected by terminal deoxynucleotidy transferase-mediated dUTP-biotin nick end labeling. The expression of p53 gene was analyzed by immunohistochemistry, Western blot and realtime-PCR. PCR-SSCP was used to detect the mutation of p53 in lung tissues. Results: Compared with those in the control group, the apoptotic index were increased significantly in 30 WLM and 60 WLM groups (t=18.11, -10.30, P<0.05). The p53 protein was increased significantly (t=-11.08, P<0.05; t=-7.00, P<0.05) in 30 WLM and 60 WLM groups. The mutation of p53 gene was not detected in lungs of radon-exposure mice. Conclusions: Lung and bronchus might be the targets of radon and its progeny, and p53 gene plays an important role in the progression of radon-induced lung injury. (authors)

  17. Effect of BRAFV600E mutation on transcription and post-transcriptional regulation in a papillary thyroid carcinoma model

    Guenther Simone M

    2007-03-01

    Full Text Available Abstract Background microRNAs (miRNAs are a group of non-coding single stranded RNAs measuring approximately 22 nucleotides in length that have been found to control cell growth, differentiation and apoptosis. They negatively regulate target genes and have recently been implicated in tumourigenesis. Furthermore, miRNA expression profiling correlates with various cancers, with these genes thought to act as both tumour suppressors and oncogenes. Recently, a point mutation in the BRAF gene leading to a V600E substitution has been identified as the most common genetic change in papillary thyroid carcinoma (PTC occurring in 29–69% of cases. This mutation leads to aberrant MAPK activation that is implicated in tumourigenesis. Aim The aim of this study was to identify the effect that BRAF oncogene has on post-transcriptional regulation in PTC by using microRNA analysis. Results A unique miRNA expression signature differentiated between PTC cell lines with BRAF mutations and a normal thyroid cell line. 15 miRNAs were found to be upregulated and 23 miRNAs were downregulated. Several of these up/down regulated miRNAs may be involved in PTC pathogenesis. miRNA profiling will assist in the elucidation of disease pathogenesis and identification biomarkers and targets.

  18. Parkinson disease-linked GBA mutation effects reversed by molecular chaperones in human cell and fly models.

    Sanchez-Martinez, Alvaro; Beavan, Michelle; Gegg, Matthew E; Chau, Kai-Yin; Whitworth, Alexander J; Schapira, Anthony H V

    2016-01-01

    GBA gene mutations are the greatest cause of Parkinson disease (PD). GBA encodes the lysosomal enzyme glucocerebrosidase (GCase) but the mechanisms by which loss of GCase contributes to PD remain unclear. Inhibition of autophagy and the generation of endoplasmic reticulum (ER) stress are both implicated. Mutant GCase can unfold in the ER and be degraded via the unfolded protein response, activating ER stress and reducing lysosomal GCase. Small molecule chaperones that cross the blood brain barrier help mutant GCase refold and traffic correctly to lysosomes are putative treatments for PD. We treated fibroblast cells from PD patients with heterozygous GBA mutations and Drosophila expressing human wild-type, N370S and L444P GBA with the molecular chaperones ambroxol and isofagomine. Both chaperones increased GCase levels and activity, but also GBA mRNA, in control and mutant GBA fibroblasts. Expression of mutated GBA in Drosophila resulted in dopaminergic neuronal loss, a progressive locomotor defect, abnormal aggregates in the ER and increased levels of the ER stress reporter Xbp1-EGFP. Treatment with both chaperones lowered ER stress and prevented the loss of motor function, providing proof of principle that small molecule chaperones can reverse mutant GBA-mediated ER stress in vivo and might prove effective for treating PD. PMID:27539639

  19. [Morphogenetic effects of the interaction of floral mutations petal-sepal and anther in petal in Papaver somniferum l].

    Beliaeva, P G

    2001-01-01

    The morphogenetic effects of the interaction of the floral mutations petal-sepal and anther in petal in Papaver somniferum L. with a monocarpic shoot were studied. During analysis of the mutations controlled by the genes ptsp and Ant, no plants of the double-mutant class were found in the second generation, in which microsporangia form on the corolla sepal structures. The ratio of phenotypic classes obtained in the experiment corresponds to that inheritance, when the genetic control of mutant characters is realized by nonallele nonlinked genes Ant and ptsp upon epistatic interaction of these genes. These data were confirmed by analysis of the genotypes of F2 plants from the phenotypic class petal-sepal, which include plants that carry both mutant genes Ant and ptsp. The results obtained suggest that the gene Ant, which controls the formation of microsporangia in the corolla metameres, is not expressed in the presence of a mutation of the gene ptsp; i.e., microsporangia are not formed in tissues with photosynthesizing cells. It is evident that the development of microsporangia is determined by the level of a product of the gene Ptsp. The role of flavonols (quercetin), inhibitors of photosynthesis, as a mechanism of regulation of activity of the genes controlling morphogenesis of the corolla elements and differentiation of microsporangia, is discussed. PMID:11605406

  20. Addition effect of erbium(III) trifluoromethanesulfonate in the homopolymerization kinetics of a DGEBA resin

    Solid bisphenol-A epoxy resin of medium molecular weight was cured using a Lewis acid initiator (erbium(III) trifluoromethanesulfonate) in three different proportions (0.5, 1 and 2 phr). A kinetic study was performed in a differential scanning calorimeter. The complete kinetic triplet was determined (activation energy, pre-exponential factor, and integral function of the deg.ree of conversion) for each system. A kinetic analysis was performed with an integral isoconversional procedure (model-free), and the kinetic model was determined both with the Coats-Redfern method (the obtained isoconversional E value being accepted as the effective activation energy) and through the compensation effect. All the systems followed the same isothermal curing model simulated from non-isothermal ones. The 'nucleation and growth' Avrami kinetic model A 3/2 has been proposed as the polymerization kinetic model. The addition of initiator accelerated the reaction having higher influence when low temperatures were applied

  1. Study of effect of addition of fly ash on radon exhalation rate in cement samples

    Most of the building materials like cement and fly ash contain naturally occurring radioactive materials (NORM). Increased interest in measuring radon exhalation rate in building products is due to the concern about health hazards of NORM. This paper focuses on studying the effect of addition of fly ash on radon exhalation rate in cement samples. Ordinary Portland Cement (OPC) and coal fly ash were used for finding the exhalation rate of cement in this paper. To study the effect on exhalation rate of cement, fly ash is added in different proportions to cement samples. The measurement was conducted by CAN Technique using SSNTDs. A gradual increase has been observed in radon exhalation rate up to certain proportion and then start to decrease. (author)

  2. REBOUNDx: A library for adding additional effects to N-body simulations

    Tamayo, Daniel; Rein, Hanno; Shi, Pengshuai

    2016-05-01

    Many astrophysical applications involve additional perturbations beyond point-source gravity. We have recently developed REBOUNDx, a library for adding such effects in numerical simulations with the open-source N-body package REBOUND. Various implementations have different numerical properties that in general depend on the underlying integrator employed. In particular, I will discuss adding velocity-dependent/dissipative effects to widely used symplectic integrators, and how one can estimate the introduced numerical errors using the operator-splitting formalism traditionally applied to symplectic integrators. Finally, I will demonstrate how to use the code, and how the Python wrapper we have developed for REBOUND/REBOUNDx makes it easy to interactively leverage powerful analysis, visualization and parallelization libraries.

  3. Effects of milling process and alloying additions on oxide particle dispersion in austenitic stainless steel

    An oxide dispersion strengthened (ODS) austenitic stainless steel was developed by mechanical alloying (MA) of advanced SUS316 stainless steel. A nano-characterization was performed to understand details of the effect of minor alloying elements in the distribution of dispersoids. It is shown that Y2O3 particles dissolve into the austenitic matrix after the MA for 6 h. Annealing at 1073 K or higher temperatures result in a distribution of fine oxide particles in the recrystallized grains in the ODS austenitic stainless steel. Additions of Hafnium or Zirconium led to the distribution of finer oxide particles than in samples without these elements, resulting in an increase in the hardness of the samples. The most effective concentration of Hf and Zr to increase the hardness was 0.6 and 0.2–0.3 wt%, respectively

  4. Impact of Zn, Mg, Ni and Co elements on glass alteration: Additive effects

    Aréna, H.; Godon, N.; Rébiscoul, D.; Podor, R.; Garcès, E.; Cabie, M.; Mestre, J.-P.

    2016-03-01

    The minor elements present in the nuclear glass composition or coming from the groundwater of the future repository may impact glass alteration. In this study, the effects of Zn, Mg, Ni and Co on the International Simple Glass (ISG) alteration were studied throughout 511 days of aqueous leaching experiments. The aim was to determine their additive or competitive effect on glass alteration and the nature of the alteration products. The four elements were introduced separately or altogether in solution as XCl2 chloride salts (X = Zn, Mg, Ni or Co) with monthly additions to compensate for their consumption. The alteration kinetics were determined by leachate analyses (ICP-AES) and alteration products were characterized in terms of composition, morphology and microstructure (SEM, TEM-EDX, ToF-SIMS and XRD). Results indicate that when they are introduced separately, Zn, Mg, Ni and Co have the same qualitative and quantitative effect on glass alteration kinetics and on pH: they form secondary phases leading to a pH decrease and a significant increase in glass alteration. The secondary phases were identified as silicates of the added X element: trioctahedral smectites with a stoichiometry of[(Si(4-a) Ala) (X(3-b) Alb) O10 (OH)2](a+b)- [Xc Nad Cae] (2c+d+2e) + with a = 0.11 to 0.45, b = 0.00 to 0.29, c = 0, d = 0.19 to 0.74 and e = 0.10 to 0.14. . It was shown that as pH stabilizes at a minimum value, X-silicates no longer precipitate, thus leading to a significant drop in the glass alteration rate. This pH value depends on X and it has been identified as being 8 for Mg-silicates, probably around 7.3 for Ni and Co-silicates and less than 6.2 for Zn-silicates. When tested together, the effects of these four elements on glass alteration are additive and lead to the formation of a mix of X-silicates that precipitate as long as their constitutive elements are available and the pH is above their respective minimum value. This study brings new quantitative information about the

  5. Effects of Rice Straw and Its Biochar Addition on Soil Labile Carbon and Soil Organic Carbon

    YIN Yun-feng; HE Xin-hua; GAO Ren; MA Hong-liang; YANG Yu-sheng

    2014-01-01

    Whether the biochar amendment could affect soil organic matter (SOM) turnover and hence soil carbon (C) stock remains poorly understood. Effects of the addition of 13C-labelled rice straw or its pyrolysed biochar at 250 or 350°C to a sugarcane soil (Ferrosol) on soil labile C (dissolved organic C, DOC;microbial biomass C, MBC;and mineralizable C, MC) and soil organic C (SOC) were investigated after 112 d of laboratory incubation at 25°C. Four treatments were examined as (1) the control soil without amendment (Soil);(2) soil plus 13C-labelled rice straw (Soil+Straw);(3) soil plus 250°C biochar (Soil+B250) and (4) soil plus 350°C biochar (Soil+B350). Compared to un-pyrolysed straw, biochars generally had an increased aryl C, carboxyl C, C and nitrogen concentrations, a decreased O-alkyl C and C:N ratio, but similar alkyl C and d13C (1 742-1 877‰). Among treatments, signiifcant higher DOC, MBC and MC derived from the new C (straw or biochar) ranked as Soil+Straw>Soil+B250>Soil+B350, whilst signiifcant higher SOC from the new C as Soil+B250>Soil+Straw≈Soil+B350. Compared to Soil, DOC and MBC derived from the native soil were decreased under straw or biochar addition, whilst MC from the native soil was increased under straw addition but decreased under biochar addition. Meanwhile, native SOC was similar among the treatments, irrespective of the straw or biochar addition. Compared to Soil, signiifcant higher total DOC and total MBC were under Soil+Straw, but not under Soil+B250 and Soil+B350, whilst signiifcant higher total MC and total SOC were under straw or biochar addition, except for MC under Soil+B350. Our results demonstrated that the application of biochar to soil may be an appropriate management practice for increasing soil C storage.

  6. Effects of nitrogen ion irradiation on endoglucanase activity and gene mutation of Bacillus subtilis Bac01

    Bacillus subtilis Bac01 was mutated by 15 keV N+ ions of 1.5xl016 cm-2. The mutant strain Bac11 with high yield of endoglucanase was isolated using carboxymethylcellulose sodium and congo red indicative plates. It exhibited higher endoglucanase activity (381.89IU) than the original strain Bac01 (93.33IU). Two 1,500 bp endoglucanase gene fragments were obtained with PCR amplification from B. subtilis Bac01 and mutant strain Bac11. BLAST comparison result indicated that 10 nucleotides mutated. Bioinformatics methods were used to analyze the two predicted amino acid sequences, and it was found that 5 amino acid residues changed, being all in the cellulose-binding domain of endoglucanase. (authors)

  7. Supra-additive effects of tramadol and acetaminophen in a human pain model.

    Filitz, Jörg; Ihmsen, Harald; Günther, Werner; Tröster, Andreas; Schwilden, Helmut; Schüttler, Jürgen; Koppert, Wolfgang

    2008-06-01

    The combination of analgesic drugs with different pharmacological properties may show better efficacy with less side effects. Aim of this study was to examine the analgesic and antihyperalgesic properties of the weak opioid tramadol and the non-opioid acetaminophen, alone as well as in combination, in an experimental pain model in humans. After approval of the local Ethics Committee, 17 healthy volunteers were enrolled in this double-blind and placebo-controlled study in a cross-over design. Transcutaneous electrical stimulation at high current densities (29.6+/-16.2 mA) induced spontaneous acute pain (NRS=6 of 10) and distinct areas of hyperalgesia for painful mechanical stimuli (pinprick-hyperalgesia). Pain intensities as well as the extent of the areas of hyperalgesia were assessed before, during and 150 min after a 15 min lasting intravenous infusion of acetaminophen (650 mg), tramadol (75 mg), a combination of both (325 mg acetaminophen and 37.5mg tramadol), or saline 0.9%. Tramadol led to a maximum pain reduction of 11.7+/-4.2% with negligible antihyperalgesic properties. In contrast, acetaminophen led to a similar pain reduction (9.8+/-4.4%), but a sustained antihyperalgesic effect (34.5+/-14.0% reduction of hyperalgesic area). The combination of both analgesics at half doses led to a supra-additive pain reduction of 15.2+/-5.7% and an enhanced antihyperalgesic effect (41.1+/-14.3% reduction of hyperalgesic areas) as compared to single administration of acetaminophen. Our study provides first results on interactions of tramadol and acetaminophen on experimental pain and hyperalgesia in humans. Pharmacodynamic modeling combined with the isobolographic technique showed supra-additive effects of the combination of acetaminophen and tramadol concerning both, analgesia and antihyperalgesia. The results might act as a rationale for combining both analgesics. PMID:17709207

  8. Effects of minor yttrium addition on hot deformability of lamellar Ti-45Al-5Nb alloy

    CHEN Yu-yong; LI Bao-hui; KONG Fan-tao

    2007-01-01

    The effects of 0.3%(molar fraction, the same below) yttrium addition on hot deformability of lamellar Ti-45Al-5Nb alloy were investigated by simulated isothermal forging tests. The ingots with the nominal compositions of Ti-45Al-5Nb and Ti-45Al-5Nb-0.3Y were prepared by induction skull melting. Simulated isothermal forging tests were conducted on Gleeble 1500D thermo-simulation machine using a 6 mm in diameter and 10 mm in length compressive specimen at the deformation temperatures of 1 100, 1 150, 1 200 ℃ and strain rates of 1.0, 0.1, 0.01 s-1. The results show that yttrium addition remarkably improves hot deformability of Ti-45Al-5Nb alloy. An appropriate hot deformation processing parameter of Ti-45Al-5Nb-0.3Y alloy is determined as 1 200 ℃, 0.01 s-1. The flow stresses are decreased by yttrium addition under the same compressive conditions. The activation energies of deformation Q are calculated as 448.6 and 399.5 kJ/mol for Y-free and Y-containing alloys, respectively. The deformed microstructure observation under 1 200 ℃, 0.01 s-1 condition indicates that Ti-45Al-5Nb-0.3Y alloy shows more dynamic recrystallization. The improvement of hot deformability of Ti-45Al-5Nb-0.3Y alloy induced by yttrium addition should be attributed to that the smaller the original lamellar colonies, the lower the deformation resistance and activation energy of deformation are, and the more the dynamic recrystallization is.

  9. Effect of methylene methanedisulfonate as an additive on the cycling performance of spinel lithium titanate electrode

    Wang, Renheng; Li, Xinhai; Zhang, Bao, E-mail: 123501032@csu.edu.cn; Wang, Zhixing; Guo, Huajun

    2015-11-05

    In order to overcome the poor cyclability of lithium-ion batteries with spinel lithium titanate (Li{sub 4}Ti{sub 5}O{sub 12}), methylene methanedisulfonate (MMDS) is evaluated as electrolyte additive. The linear sweep voltammetry (LSV) and electrochemical impedance spectroscopy (EIS) indicate that MMDS participates in the formation process of the solid electrolyte interface (SEI) film above 1 V, which is due to the interfacial reaction between the electrode and electrolyte: Li{sub 4}Ti{sub 5}O{sub 12} anodes are previously considered free from SEI films when cycled between 1 and 3 V. The stable SEI film around Li{sub 4}Ti{sub 5}O{sub 12} is seen most effective as a barrier layer in suppressing the interfacial reaction and resulting gassing from the Li{sub 4}Ti{sub 5}O{sub 12} surface. In addition, the results of electrochemical impedance spectroscopy (EIS), X-ray photoelectron spectroscopy (XPS), scanning electron microscope (SEM) and transmission electron microscopy (TEM) demonstrate that a thin and good conductive film can be formed on the Li{sub 4}Ti{sub 5}O{sub 12} surface ascribed to MMDS additive, which resulting the improvement of conductivity and a good ability of Li{sup +} migration. - Highlights: • MMDS used as additive to improve cycling performance of the Li{sub 4}Ti{sub 5}O{sub 12}/Li cells. • A SEI film can be formed using MMDS in the electrolyte above 1 V. • Sulfur-containing species is the main component of the SEI formed by MMDS.

  10. Effects on human transcriptome of mutated BRCA1 BRCT domain: A microarray study

    Iofrida Caterina; Melissari Erika; Mariotti Veronica; Guglielmi Chiara; Guidugli Lucia; Caligo Maria; Pellegrini Silvia

    2012-01-01

    Abstract Background BRCA1 (breast cancer 1, early onset) missense mutations have been detected in familial breast and ovarian cancers, but the role of these variants in cancer predisposition is often difficult to ascertain. In this work, the molecular mechanisms affected in human cells by two BRCA1 missense variants, M1775R and A1789T, both located in the second BRCT (BRCA1 C Terminus) domain, have been investigated. Both these variants were isolated from familial breast cancer patients and t...

  11. The effect of plants with novel traits (PNT) regulation on mutation breeding in Canada

    In 1988 the Parliament of Canada passed the Canadian Environmental Protection Act (CEPA) into law. Within this Act is a definition for biotechnology which reads 'the application of science and engineering in the direct or indirect use of living organisms or parts or products of living organisms in their natural or modified forms'. The definition was placed in CEPA to deal with concerns regarding Genetically Modified Organisms (GMOs) and would allow Environment Canada to regulate all GMOs. In response to CEPA the Canadian Food Inspection Agency (CFIA), which is responsible for registration of plant varieties in Canada, developed the concept of a Plant with Novel Traits (PNT) defined as 'a plant variety possessing a characteristic that is intentionally selected or created through a specific genetic change and is either not previously associated with a distinct and stable population of the cultivated plant species in Canada or expressed outside the normal range of a similar existing characteristic in the plant species'. Not only does this definition capture GMOs it also includes induced mutations, natural mutations and exotic germplasm that have not previously been grown in Canada. It is, as CFIA has argued, a system that is product not process based. However, apart from questions regarding the novelty of traits in new plant varieties, breeders are asked by CFIA to identify the process used to develop the trait or traits in question. Field trials involving breeding lines with a PNT may be subject to confined testing. This conference celebrates 70 years of unconfined development and testing of induced plant mutations. This regulation is time consuming, expensive and an innovation barrier for Canadian plant breeding. It can only be hoped that other nations, and particularly those that have successfully used induced mutations, will not emulate Canada's approach. (author)

  12. Effect of Co addition on crystallization and magnetic properties of FeSiBPCu alloy

    Rui Xiang; Shaoxiong Zhou; Bangshao Dong; Guangqiang Zhang; Zongzhen Li; Yanguo Wang; Chuntao Chang

    2014-01-01

    The effects of Co addition on the microstructure, crystallization processes and soft magnetic properties of (Fe1-xCox)83Si4B8P4Cu1 (x=0.35, 0.5, 0.65) alloys were investigated. The experimental results demonstrated that the addition of Co decreased the thermal stability against crystallization of the amorphous phase, and thus improved the heat treatment temperature of this alloy. FeCoSiBPCu nanocrystalline alloys with a dispersedα'-FeCo phase were obtained by appropriately annealing the as-quenched ribbons at 763 K for 10 min. Theα'-FeCo with grains size ranging from 9 to 28 nm was identified in primary crystallization. The coercivity (Hc) markedly increased with increasing x and exhibited a minimum value at x=0.35, while the saturation magnetic flux density (Bs) shows a slight decrease. The (Fe0.65Co0.35)83Si4B8P4Cu1 nanocrystalline alloy exhibited a high saturation magnetic flux density Bs of 1.68 T, a low coercivity, Hc of 5.4 A/m and a high effective permeability μe of 29,000 at 1 kHz.

  13. Cell size dependence of additive versus synergetic effects of UV radiation and PAHs on oceanic phytoplankton

    Echeveste, Pedro, E-mail: pecheveste@imedea.uib-csic.es [Department of Global Change Research, IMEDEA (CSIC-UIB) Instituto Mediterraneo de Estudios Avanzados, Miquel Marques 21, 07190 Esporles, Illes Balears (Spain); Agusti, Susana [Department of Global Change Research, IMEDEA (CSIC-UIB) Instituto Mediterraneo de Estudios Avanzados, Miquel Marques 21, 07190 Esporles, Illes Balears (Spain); Dachs, Jordi [Department of Environmental Chemistry, Institute of Environmental Assessment and Water Research, IDAEA-CSIC, Barcelona, Catalunya (Spain)

    2011-05-15

    Polycyclic Aromatic Hydrocarbons' (PAHs) toxicity is enhanced by the presence of ultraviolet radiation (UVR), which levels have arisen due to the thinning of the ozone layer. In this study, PAHs' phototoxicity for natural marine phytoplankton was tested. Different concentrations of a mixture of 16 PAHs were added to natural phytoplankton communities from the Mediterranean Sea, Atlantic, Arctic and Southern Oceans and exposed to natural sunlight received in situ, including treatments where the UVR bands were removed. PAHs' toxicity was observed for all the phytoplankton groups studied in all the waters and treatments tested, but only for the pico-sized group a synergetic effect of the mixture and UVR was observed (p = 0.009). When comparing phototoxicity in phytoplankton from oligotrophic and eutrophic waters, synergy was only observed at the oligotrophic communities (p = 0.02) where pico-sized phytoplankton dominated. The degree of sensitivity was related to the trophic degree, decreasing as Chlorophyll a concentration increased. - Highlights: > The smallest picocyanobacteria were the most sensitive to PAHs and UVR. > PAHs-UVR synergism for the picophytoplankton and the oligotrophic communities. > PAHs-UVR additivity for the nanophytoplankton and the eutrophic communities. > An irradiance threshold is suggested to determine the joint action of UVR and PAHs. - Cell size and UVR levels determine additive/synergetic effects of PAHs and UVR to oceanic phytoplankton.

  14. Cell size dependence of additive versus synergetic effects of UV radiation and PAHs on oceanic phytoplankton

    Polycyclic Aromatic Hydrocarbons' (PAHs) toxicity is enhanced by the presence of ultraviolet radiation (UVR), which levels have arisen due to the thinning of the ozone layer. In this study, PAHs' phototoxicity for natural marine phytoplankton was tested. Different concentrations of a mixture of 16 PAHs were added to natural phytoplankton communities from the Mediterranean Sea, Atlantic, Arctic and Southern Oceans and exposed to natural sunlight received in situ, including treatments where the UVR bands were removed. PAHs' toxicity was observed for all the phytoplankton groups studied in all the waters and treatments tested, but only for the pico-sized group a synergetic effect of the mixture and UVR was observed (p = 0.009). When comparing phototoxicity in phytoplankton from oligotrophic and eutrophic waters, synergy was only observed at the oligotrophic communities (p = 0.02) where pico-sized phytoplankton dominated. The degree of sensitivity was related to the trophic degree, decreasing as Chlorophyll a concentration increased. - Highlights: → The smallest picocyanobacteria were the most sensitive to PAHs and UVR. → PAHs-UVR synergism for the picophytoplankton and the oligotrophic communities. → PAHs-UVR additivity for the nanophytoplankton and the eutrophic communities. → An irradiance threshold is suggested to determine the joint action of UVR and PAHs. - Cell size and UVR levels determine additive/synergetic effects of PAHs and UVR to oceanic phytoplankton.

  15. Effect of zirconium addition on welding of aluminum grain refined by titanium plus boron

    Aluminum oxidizes freely in ordinary atmosphere which makes its welding difficult and weak, particularly it solidifies in columnar structure with large grains. Therefore, it is anticipated that the effect of addition of some grain refiners to its melt before solidification is worth while investigating as it may enhance its weldabilty and improve its mechanical strength. In this paper, the effect of addition of zirconium at a weight of 0.1% (which corresponds to the peretictic limit on the aluminum-zirconium base phase diagram) to commercially pure aluminum, grain refined by Ti+B on its weldability, using gas tungsten arc welding, GTAW, method which was formerly known as TIG. A constant current level of 30 AC Ampere was used because it removes the oxides during the welding process. Metallographic examination of the weldments of the different combinations of Al with Al and Al with its microalloys: in the heat affected zone, HAZ, and away from it was carried out and examined for HAZ width, porosity, cracks and microhardness. It was found that grain refining by Ti+B or Zr resulted in enhancement of the weldment

  16. Effect of zirconium addition on welding of aluminum grain refined by titanium plus boron

    Aluminum oxidizes freely in ordinary atmosphere which makes its welding difficult and weak, particularly it solidifies in columnar structure with large grains. Therefore, it is anticipated that the effect of addition of some grain refiners to its melt before solidification is worth while investigating as it may enhance its weldabilty and improve its mechanical strength. In this paper, the effect of addition of zirconium at a weight of 0.1 percentage (which corresponds to the peretictic limit on the aluminum-zirconium base phase diagram) to commercially pure aluminum, grain refined by Tau i+Beta on its weldability, using gas tungsten arc welding, GTAW, method which was formerly known as TIG. A constant current level of 30 AC Ampere was used because it removes the oxides during the welding process. Metallographic examination of the weldments of the different combinations of Al with Al and Al with its microalloys: in the heat affected zone, HAZ, and away from it was carried out and examined for HAZ width, porosity, cracks and microhardness. It was found that grain refining by Tau i+Beta or Zr resulted in enhancement of the weldment. (author)

  17. Effect of PAC addition on immersed ultrafiltration for the treatment of algal-rich water.

    Zhang, Yan; Tian, Jiayu; Nan, Jun; Gao, ShanShan; Liang, Heng; Wang, Meilian; Li, Guibai

    2011-02-28

    The aim of this study was to evaluate the effect of powdered activated carbon (PAC) addition on the treatment of algal-rich water by immersed ultrafiltration (UF), in terms of permeate quality and membrane fouling. Experiments were performed with a hollow-fiber polyvinyl chloride ultrafiltration membrane at a laboratory scale, 20-25°C and 10 L/(m(2) h) constant permeate flux. UF could achieve an absolute removal of Microcystis aeruginosa cells, but a poor removal of algogenic organic matter (AOM) released into water, contaminants responsible for severe membrane fouling. The addition of 4 g/L PAC to the immersed UF reactor significantly alleviated the development of trans-membrane pressure and enhanced the removal of dissovled organic carbon (by 10.9±1.7%), UV(254) (by 27.1±1.7%), and microcystins (expressed as MC-LR(eq), by 40.8±4.2%). However, PAC had little effect on the rejection of hydrophilic high molecular weight AOM such as carbohydrates and proteins. It was also identified that PAC reduced the concentrations of carbohydrates and proteins in the reactor due to decreased light intensity, as well as the MC-LR(eq) concentration by PAC adsorption. PMID:21216530

  18. Effect of PAC addition on immersed ultrafiltration for the treatment of algal-rich water

    Zhang Yan, E-mail: zhang.yan113@163.com [State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, 73 Huanghe Road, Nangang District, Harbin 150090 (China); Tian Jiayu; Nan Jun; Gao Shanshan; Liang Heng; Wang Meilian; Li Guibai [State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, 73 Huanghe Road, Nangang District, Harbin 150090 (China)

    2011-02-28

    The aim of this study was to evaluate the effect of powdered activated carbon (PAC) addition on the treatment of algal-rich water by immersed ultrafiltration (UF), in terms of permeate quality and membrane fouling. Experiments were performed with a hollow-fiber polyvinyl chloride ultrafiltration membrane at a laboratory scale, 20-25 deg, C and 10 L/(m{sup 2} h) constant permeate flux. UF could achieve an absolute removal of Microcystis aeruginosa cells, but a poor removal of algogenic organic matter (AOM) released into water, contaminants responsible for severe membrane fouling. The addition of 4 g/L PAC to the immersed UF reactor significantly alleviated the development of trans-membrane pressure and enhanced the removal of dissovled organic carbon (by 10.9 {+-} 1.7%), UV{sub 254} (by 27.1 {+-} 1.7%), and microcystins (expressed as MC-LR{sub eq}, by 40.8 {+-} 4.2%). However, PAC had little effect on the rejection of hydrophilic high molecular weight AOM such as carbohydrates and proteins. It was also identified that PAC reduced the concentrations of carbohydrates and proteins in the reactor due to decreased light intensity, as well as the MC-LR{sub eq} concentration by PAC adsorption.

  19. Immunotoxic effects of the color additive caramel color III: immune function studies in rats.

    Houben, G F; Penninks, A H; Seinen, W; Vos, J G; Van Loveren, H

    1993-01-01

    Administration of the color additive caramel color III (AC) may cause a reduction in total white blood cell counts in rats due to reduced lymphocyte counts. Beside lymphopenia, several other effects in rat have been described. The effects are caused by the imidazole derivative 2-acetyl-4(5)-(1,2,3,4-tetrahydroxybutyl)imidazole (THI) and occur in rats fed a diet low in vitamin B6. In the present paper, immune function studies on AC and THI with rats fed a diet low, but not deficient in vitamin B6 are presented and discussed. Rats were exposed to 0.4 or 4% AC or to 5.72 ppm THI in drinking water during and for 28 days prior to the start of immune function assays. Resistance to Trichinella spiralis was examined in an oral infection model and clearance of Listeria monocytogenes upon an intravenous infection was studied. In addition, natural cell-mediated cytotoxicity of splenic and nonadherent peritoneal cells and the antibody response to sheep red blood cells were studied. From the results it is concluded that exposure of rats to AC or THI influenced various immune function parameters. Thymus-dependent immunity was suppressed, while parameters of the nonspecific resistance were also affected, as shown by a decreased natural cell-mediated cytotoxicity in the spleen and an enhanced clearance of L. monocytogenes. PMID:8432426

  20. EFFECT OF THYME ESSENTIAL OIL ADDITION ON PHYSICAL AND MICROBIOLOGICAL QUALITY OF TABLE EGGS

    Henrieta Arpášová

    2013-02-01

    Full Text Available Essentialoils areintensivefragrant, oilyliquidsubstances containedindifferent parts of theplant. Their function is based on organoleptic effect and stimulation of organism to the production of digestive juices. Result is ahigherdigestibilityandabsorption of nutirents. Besides antibacterial properties, essential oils or their components have been shown to exhibit antiviral,antimycotic, antitoxigenic, antiparasitic, and insecticidal properties. In this experiment the effects of supplementation of the diet for laying hens with thyme essential oils on physical and microbiological egg parameters were studied.Hens of laying hybrid Hy-Line Brown (n=30 were randomly divided into 3 groups (n=10 and fed for 23 weeks on diets with thyme essential oil supplemented. In the first experimental group the feed mixture was supplemented with thyme essential oil addition in a dose 0.5 g/kg, in the second one some essential oil in a dose 1g/kg. The results suggest that all of qualitative parameters of egg internal content (yolk weight (g, yolk index, percentage portion egg yolk (%, yolk index, yolk colour (°HLR, albumen weight (g, percentage portion of albumen (%, Haugh Units (HU, albumen index were with thyme essential oil addition insignificantly influenced (P>0.05. The number of coliforms, enterococci, fungi and yeasts decreased with increasing dose of oil. The number of lactobacilli was zero in all groups.