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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Isolation, characterization and cloning of lectins from the Chinese daffodil: narcissus tazetta var. chinensis. / CUHK electronic theses & dissertations collection

January 1998 (has links)
by Linda Shiou-Mei Ooi. / Thesis (Ph.D.)--Chinese University of Hong Kong, 1998. / Includes bibliographical references (p. 118-126). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Mode of access: World Wide Web. / Abstracts in English and Chinese.
2

Studies on isolation and characterization of fungal, plant and animal defense proteins (lectins, ribosome-inactivating protein and antifungal protein). / CUHK electronic theses & dissertations collection

January 2001 (has links)
by Lam Ying Wai. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2001. / Includes bibliographical references (p. 193-209). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Mode of access: World Wide Web. / Abstracts in English and Chinese.
3

Isolation, characterization and pharmacokinetics of antioxidants from Hawthorn. / CUHK electronic theses & dissertations collection

January 2002 (has links)
Qi Chang. / "March 2002." / Thesis (Ph.D.)--Chinese University of Hong Kong, 2002. / Includes bibliographical references (p. 173-192). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Mode of access: World Wide Web. / Abstracts in English and Chinese.
4

Nasopharynx and mucosa associated lymphatic tissue : studies on mucosal immunity, nasopharyngeal colonization with non-encapsulated non-typable Haemophilus influenzae and local administration of immunoglobulin in the upper respiratory tract /

Lindberg, Karin, January 1900 (has links)
Diss. (sammanfattning) Stockholm : Karol. inst. / Härtill 6 uppsatser.
5

Cloning and characterization of EcoHK31I restriction and modification system from escherichia coli HK31.

January 1995 (has links)
by Lee Kai Fai, Calvin. / Thesis (Ph.D.)--Chinese University of Hong Kong, 1995. / Includes bibliographical references (leaves 159-167). / ACKNOWLEDGMENTS --- p.i / ABSTRACT --- p.ii / CONTENTS --- p.iv / ABBREVIATIONS --- p.xi / Chapter CHAPTER ONE --- General Introduction --- p.1 / Chapter 1.1 --- The Phenomenon of Host-controlled Restriction --- p.1 / Chapter 1.2 --- Classification of Restriction and Modification Systems --- p.2 / Chapter 1.2.1 --- Type I Restriction-Modification Systems --- p.2 / Chapter 1.2.2 --- Type II Restriction-Modification Systems --- p.3 / Chapter 1.2.3 --- Type III Restriction-Modification Systems --- p.4 / Chapter 1.2.4 --- Type IV Restriction-Modification Systems --- p.5 / Chapter 1.3 --- Occurrence of Restriction-Modification Systems --- p.6 / Chapter 1.4 --- Effect of Methylation --- p.7 / Chapter 1.5 --- Alternation of Recognition Specificities --- p.7 / Chapter 1.5.1 --- Cross Protection by DNA Methyltransferase --- p.8 / Chapter 1.5.2 --- A-Assisted Restriction Endonuclease (RARE) Cleavage --- p.9 / Chapter 1.5.3 --- Site-specific Cleavage mediated by Triple-helix formation --- p.9 / Chapter 1.5.4 --- Site-specific Cleavage of Duplex DNA with a λ repressor- Staphylococcal Nuclease Hybrid --- p.10 / Chapter 1.5.5 --- Achilles' heel Cleavage --- p.10 / Chapter 1.5.6 --- Chimeric Restriction Endonuclease --- p.11 / Chapter 1.6 --- Cloning of Restriction and Modification Systems --- p.11 / Chapter 1.6.1 --- Selection based on Modification --- p.11 / Chapter 1.6.2 --- Other Cloning Strategies --- p.12 / Chapter 1.6.2.1 --- Sub-Cloning of Plasmids --- p.12 / Chapter 1.6.2.2 --- Selection based on Restriction --- p.13 / Chapter 1.6.2.3 --- Multi-step Cloning --- p.13 / Chapter 1.6.2.4 --- Cloning in AP1-200 and AP1-200-9 strain --- p.13 / Chapter 1.6.2.5 --- Direct Cloning of Restriction gene by 'endo-blue' method --- p.14 / Chapter 1.7 --- Genetic Location of Restriction-Modification Systems --- p.14 / Chapter 1.8 --- Sequences of Restriction-Modification Systems --- p.15 / Chapter 1.9 --- Catalytic Properties of Type II Restriction-Modification Systems --- p.17 / Chapter 1.10 --- Crystallography of Type II Restriction and Modification Enzymes --- p.19 / Chapter 1.11 --- Evolution of Type II Restriction and Modification Enzymes --- p.22 / Chapter 1.12 --- Aim of Study --- p.23 / Chapter CHAPTER TWO --- Materials and Methods --- p.24 / Chapter 2.1 --- Bacterial Strains --- p.24 / Chapter 2.2 --- General Techniques --- p.25 / Chapter 2.2.1 --- Phenol/Chloroform Extraction --- p.25 / Chapter 2.2.2 --- Ethanol Precipitation --- p.25 / Chapter 2.2.3 --- Spectrophotometry --- p.25 / Chapter 2.2.4 --- Restriction digestion of DNA --- p.26 / Chapter 2.2.5 --- Agarose Gel Electrophoresis of DNA --- p.26 / Chapter 2.2.6 --- Recovery of DNA fragment from Agarose gel --- p.26 / Chapter 2.2.7 --- Minipreparation of Plasmid --- p.27 / Chapter 2.2.8 --- Large-Scale Preparation of Plasmid DNA --- p.28 / Chapter 2.2.8A --- By Equilibrium Centrifugation in Cesium Chloride- Ethidium Bromide Gradient --- p.28 / Chapter 2.2.8B --- By Using Qiagen-tip 100 Cartridge --- p.29 / Chapter 2.2.9 --- Preparation of Competent Cells --- p.30 / Chapter 2.2.10 --- Transformation of Competent Cells --- p.31 / Chapter 2.2.11 --- Screening of Recombinant Plasmids --- p.32 / Chapter 2.2.11A --- Using Selective media --- p.32 / Chapter 2.2.11B --- Rapid Alkaline Lysis Method --- p.32 / Chapter 2.2.12 --- Sodium Dodecyl Sulfate Polyacrylamide Gel Electrophoresis (SDS-PAGE) --- p.33 / Chapter 2.2.13 --- Size Exclusion Chromatography --- p.34 / Chapter 2.2.14 --- Electroblotting of Protein on Polyvinylidene Difluoride (PVDF) membrane --- p.35 / Chapter 2.2.15 --- Isoelectric Focusing (EEF) --- p.36 / Chapter 2.2.16 --- Protein Assay --- p.37 / Chapter 2.3 --- DNA Sequencing --- p.37 / Chapter 2.3.1 --- Isolation of a template DNA --- p.38 / Chapter 2.3.2 --- DNA Denaturation and Annealing Reaction --- p.38 / Chapter 2.3.3 --- Labeling and Termination Reaction --- p.38 / Chapter 2.3.4 --- DNA Sequencing Electrophoresis --- p.39 / Chapter 2.3.5 --- Autoradiography --- p.40 / Chapter CHAPTER THREE --- Purification and Characterization of Restriction Endonuclease from Escherichia coli HK31 --- p.41 / Chapter 3.1 --- Introduction --- p.41 / Chapter 3.2 --- Materials and Methods --- p.42 / Chapter 3.2.1 --- Preparation of Crude enzyme Extract --- p.42 / Chapter 3.2.2 --- Purification of R.EcoHK31I --- p.42 / Chapter 3.2.3 --- Characterization of Restriction endonuclease --- p.43 / Chapter 3.2.3.1 --- Enzyme Activity assay --- p.43 / Chapter 3.2.3.2 --- "Optimal pH, Temperature, Metal Ion and Salt concentration of R.EcoHK31I" --- p.43 / Chapter 3.2.3.3 --- Assay for the Purity of R.EcoHK31I --- p.43 / Chapter 3.2.3.4 --- Determination of Recognition Specificity --- p.44 / Chapter 3.2.3.5 --- Determination of the Cleavage Specificity --- p.44 / Chapter 3.3 --- Results and Discussion --- p.45 / Chapter 3.3.1 --- Purification ofR.EcoHK31I from Escherichia coli HK31 --- p.45 / Chapter 3.3.2 --- "Optimal pH,Temperature, Metal ions and Salt concentration of R.EcoHK31I" --- p.46 / Chapter 3.3.3 --- Unit Definition --- p.51 / Chapter 3.3.4 --- Purity of the R.EcoHK31I --- p.51 / Chapter 3.3.5 --- Recognition Site of the R.EcoHK31I --- p.51 / Chapter 3.3.6 --- Sensitivity of the R.EcoHK31I to dcm Methylation --- p.52 / Chapter 3.3.7 --- Cleavage Specificity of R.EcoHK31I --- p.52 / Chapter CHAPTER FOUR --- Cloning of EcoEK31I Restriction and Modification (R-M) System from Escherichia coli HK31 --- p.57 / Chapter 4.1 --- Introduction --- p.57 / Chapter 4.2 --- Materials and Methods --- p.58 / Chapter 4.2.1 --- Extraction of genomic DNA from E. coli HK31 --- p.58 / Chapter 4.2.2 --- Extraction of Extra-Chromosomal DNA from E. coli HK31 --- p.59 / Chapter 4.2.3 --- Restriction Digestion of the Total DNA --- p.59 / Chapter 4.2.4 --- Preparation of Linearized and Dephosphorylated Vector --- p.60 / Chapter 4.2.5 --- Fill-in Reaction --- p.60 / Chapter 4.2.6 --- Ligation between Vector and Digested Chromosomal DNA --- p.61 / Chapter 4.2.7 --- Selection of Clones Harboring Methyltransferase gene --- p.61 / Chapter 4.2.8 --- Screening of the Survival Clones --- p.62 / Chapter 4.3 --- Results --- p.62 / Chapter 4.3.1 --- Construction of Genomic Libraries --- p.62 / Chapter 4.3.2 --- Selection of the Methyltransferase Gene --- p.66 / Chapter 4.3.3 --- In vitro Detection of R.EcoHK31I activity --- p.67 / Chapter 4.3.4 --- Functional Localization of EcoHK31I --- p.67 / Chapter 4.3.5 --- Subcloning of the Complete EcoHK31I R-M System --- p.72 / Chapter 4.4 --- Discussion --- p.72 / Chapter 4.4.1 --- Construction of Genomic Libraries --- p.72 / Chapter 4.4.2 --- Cloning of EcoHK31I Restriction and Modification System --- p.75 / Chapter 4.4.2.1 --- Selecting Endonuclease --- p.75 / Chapter 4.4.2.2 --- Detection of Restriction Endonuclease Activity --- p.76 / Chapter 4.4.3 --- Functional Localization of the R-M System --- p.76 / Chapter CHAPTER FIVE --- The Nucleotide Sequences of the EcoHK31I R-M System --- p.78 / Chapter 5.1 --- Introduction --- p.78 / Chapter 5.2 --- Materials and Methods --- p.79 / Chapter 5.2.1 --- Sequencing Strategies --- p.79 / Chapter 5.2.2 --- DNA Sequencing --- p.80 / Chapter 5.2.3 --- Sequence Analysis --- p.80 / Chapter 5.3 --- Results and Discussion --- p.80 / Chapter 5.3.1 --- Nucleotide Sequences and Deduced Amino Acid sequences --- p.80 / Chapter 5.3.2 --- Comparison of Amino Acid Sequences --- p.85 / Chapter CHAPTER SIX --- Purification and Characterization of EcoHK31I Methyltransferase from E. coli K802 [pEcoHK31E] --- p.91 / Chapter 6.1 --- Introduction --- p.91 / Chapter 6.2 --- Materials and Methods --- p.92 / Chapter 6.2.1 --- Preparation of Crude enzyme Extract --- p.92 / Chapter 6.2.2 --- Purification of M.EcoHK31I --- p.92 / Chapter 6.2.3 --- Characterization of EcoHK31I Methyltransferase --- p.93 / Chapter 6.2.3.1 --- Enzyme Activity assay --- p.93 / Chapter 6.2.3.2 --- Determination of Methylation specificity --- p.93 / Chapter 6.2.3.3 --- Determination of Molecular weight of M.EcoHK31I --- p.94 / Chapter 6.2.3.4 --- Determination ofM.EcoHK31I Kinetics --- p.94 / Chapter 6.3 --- Results and Discussion --- p.96 / Chapter 6.3.1 --- Purification of EcoHK31I Methyltransferase --- p.96 / Chapter 6.3.2 --- M.EcoHK31I Modification Specificity --- p.99 / Chapter 6.3.3 --- "Determination of Molecular Weight ofM,EcoHK31I" --- p.99 / Chapter 6.3.4 --- Catalytic Properties of EcoHK31I Methyltransferase --- p.103 / Chapter 6.3.5 --- A Novel m5C-MTase M.EcoHK31I --- p.103 / Chapter CHAPTER SEVEN --- Over-expression and Characterization of EcoHK31I Restriction and Modification Enzymes --- p.106 / Chapter 7.1 --- Introduction --- p.106 / Chapter 7.1.1 --- Expression Vector pTrc series --- p.107 / Chapter 7.1.2 --- Expression Vector pET series --- p.107 / Chapter 7.2 --- Materials and Methods --- p.109 / Chapter 7.2.1 --- General technique --- p.109 / Chapter 7.2.2 --- Polymerase Chain Reaction --- p.110 / Chapter 7.2.3 --- Construction of plysSM13 --- p.110 / Chapter 7.2.4 --- Construction of pTrc99A-R36 --- p.110 / Chapter 7.2.5 --- Construction of pET3a-M38 --- p.111 / Chapter 7.2.6 --- Construction of pET3a-C23 --- p.111 / Chapter 7.2.7 --- Expression of Recombinant Proteins in E. coli hosts --- p.115 / Chapter 7.2.8 --- Purification of Recombinant R.EcoHK31I --- p.115 / Chapter 7.2.9 --- Determination of Molecular Weight of Recombinant R. EcoHK31I --- p.115 / Chapter 7.2.10 --- Polyclonal Antibodies against R.EcoHK31I --- p.116 / Chapter 7.2.11 --- Western Blotting --- p.116 / Chapter 7.2.12 --- Purification of Recombinant M.EcoHK31I polypeptide α --- p.117 / Chapter 7.2.13 --- Purification of Recombinant M.EcoHK31I polypeptide β --- p.118 / Chapter 7.2.14 --- In vitro Complementation Methylation Activity --- p.118 / Chapter 7.2.15 --- Incorporation of [3H]-AdoMet to non-methylated Lambda DNA --- p.119 / Chapter 7.3 --- Results and Discussion --- p.119 / Chapter 7.3.1 --- Expression of Recombinant R. EcoHK31I --- p.119 / Chapter 7.3.2 --- Purification and Characterization of Recombinant R.EcoHK31I --- p.120 / Chapter 7.3.2.1 --- Purification of Recombinant R.EcoHK31I --- p.120 / Chapter 7.3.2.2 --- Characterization of Recombinant R.EcoHK31I --- p.122 / Chapter 7.3.2.2.1 --- Molecular Weight and Isoelectric point of the Recombinant R.EcoHK31I --- p.122 / Chapter 7.3.2.2.2 --- Antibodies to Recombinant R.EcoHK31I --- p.125 / Chapter 7.3.3 --- Expression and Purification of M.EcoHK31Ipolypeptide α --- p.127 / Chapter 7.3.4 --- Expression and Purification of M.EcoHK31I polypeptide β --- p.127 / Chapter 7.3.5 --- Characterization of M.EcoHK31I polypeptides a and β --- p.129 / Chapter 7.3.5.1 --- Molecular Weight Determination --- p.129 / Chapter 7.3.5.2 --- Isoelectric Point Determination --- p.132 / Chapter 7.3.5.3 --- In vivo and in vitro Methylation Activity --- p.132 / Chapter CHAPTER EIGHT --- Generation and Activity Assay of Q193G Mutein of M.EcoHK31I Polypeptide a --- p.138 / Chapter 8.1 --- Introduction --- p.138 / Chapter 8.2 --- Materials and Methods --- p.139 / Chapter 8.2.1 --- Construction of pET3a-M38 (Q193G) --- p.139 / Chapter 8.2.2 --- Expression and Purification of Q193G protein --- p.140 / Chapter 8.2.3 --- In vivo and in vitro methylation activity of Q193G Mutein --- p.140 / Chapter 8.3 --- Results and Discussion --- p.145 / Chapter 8.3.1 --- "Construction, Expression and Purification of Q193G Mutein" --- p.145 / Chapter 8.3.2 --- Determination of Molecular Weight and Isoelectric point of Q193G --- p.145 / Chapter 8.3.3 --- In vivo and in vitro methylation activity of Q193G Mutein --- p.145 / Chapter 8.3.4 --- Recognition Specificity of Q193G Mutein --- p.147 / Chapter CHAPTER NINE --- General Discussion --- p.151 / REFERENCES --- p.159 / APPENDIX A --- p.168
6

Detection of hepatitis A virus in shellfish in Hong Kong.

January 1998 (has links)
by Lap-Yee Lam. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1998. / Includes bibliographical references (leaves 90-101). / Abstract also in Chinese. / Abstract --- p.i / Contents --- p.iv / List of tables --- p.ix / List of figures --- p.x / Abbreviations --- p.xi / Acknowledgements --- p.xii / Chapter Chapter 1 - --- Introduction / Chapter 1.1 --- The biology of hepatitis A virus --- p.1 / Chapter 1.1.1 --- History --- p.1 / Chapter 1.1.2 --- General characteristics of HAV --- p.2 / Chapter 1.1.3 --- Stability and disinfection of HAV --- p.3 / Chapter 1.1.4 --- Molecular biology of HAV --- p.5 / Chapter 1.1.4.1 --- Genomic organization of HAV --- p.5 / Chapter 1.1.4.2 --- Antigenic sites on the capsid of HAV --- p.8 / Chapter 1.1.5 --- Laboratory diagnosis and methods of study for HAV --- p.8 / Chapter 1.1.5.1 --- Cell-culture propagation and antigen detection --- p.8 / Chapter 1.1.5.2 --- Nucleic acid detection --- p.10 / Chapter 1.1.6 --- Epidemiology of HAV --- p.12 / Chapter 1.1.6.1 --- Distribution of HAV infection --- p.12 / Chapter 1.1.6.2 --- Seasonal pattern of HAV infection --- p.13 / Chapter 1.1.6.3 --- Mode of transmission --- p.13 / Chapter 1.1.6.4 --- Molecular epidemiology --- p.15 / Chapter 1.1.7 --- Epidemiology of HAV infection in Hong Kong --- p.15 / Chapter 1.2 --- Transmission of viruses through contaminated food --- p.18 / Chapter 1.2.1 --- Active accumulation of water contaminants by shellfish --- p.20 / Chapter 1.2.2 --- Retention of viruses by shellfish in contaminate water --- p.21 / Chapter 1.2.3 --- Elimination of viruses in contaminated shellfish --- p.21 / Chapter 1.2.4 --- Indicators for contamination by enteric viruses --- p.21 / Chapter 1.3 --- Detection of viruses from foods --- p.23 / Chapter 1.3.1 --- Recovery of viruses from foods --- p.23 / Chapter 1.3.2 --- Detection of viral nucleic acid --- p.23 / Chapter 1.4 --- Objectives of the study --- p.26 / Chapter Chapter 2- --- Materials and methods / Chapter 2.1 --- Materials --- p.27 / Chapter 2.1.1 --- Sera from patients with acute viral hepatitis --- p.27 / Chapter 2.1.2 --- Collection of shellfish samples --- p.28 / Chapter 2.1.3 --- Purified HAV preparations as positive control --- p.30 / Chapter 2.1.4 --- Control samples for the virion capture method --- p.30 / Chapter 2.1.5 --- Preparation of dissecting instruments and processing of shellfish samples --- p.30 / Chapter 2.1.6 --- Plasticwares and glasswares --- p.30 / Chapter 2.1.7 --- "Chemicals, reagents and commercial kits" --- p.31 / Chapter 2.1.7.1 --- Samples processing --- p.31 / Chapter 2.1.7.2 --- Reagents for RNA extractions --- p.31 / Chapter 2.1.7.3 --- Oligonucleotide primers synthesis --- p.33 / Chapter 2.1.7.4 --- Primers purification after synthesis --- p.34 / Chapter 2.1.7.5 --- Gel electrophoresis --- p.34 / Chapter 2.1.7.6 --- Reagents for hybridization --- p.36 / Chapter 2.2 --- Methods --- p.37 / Chapter 2.2.1 --- Samples processing --- p.37 / Chapter 2.2.2 --- Artificially seeded HAV in shellfish --- p.37 / Chapter 2.2.3 --- RNA extraction methods --- p.37 / Chapter 2.2.3.1 --- Acid phenol method --- p.37 / Chapter 2.2.3.2 --- Spin cartridge method --- p.38 / Chapter 2.2.3.3 --- Virion capture method --- p.39 / Chapter 2.2.4 --- "Oligonucleotides used for RT, PCR and hybridization" --- p.40 / Chapter 2.2.4.1 --- Oligonucleotides used in HAV RT-PCR --- p.40 / Chapter 2.2.4.2 --- Primer set used for the evaluation of inhibitors of PCR in shellfish homogenates --- p.41 / Chapter 2.2.4.3 --- Preparation of oligonucleotide primers --- p.41 / Chapter 2.2.4.4 --- Detachment of the primer from the column --- p.42 / Chapter 2.2.4.5 --- Purification of the oligonucleotides --- p.42 / Chapter 2.2.4.6 --- Confirmation of synthesed oligonucleotide --- p.43 / Chapter 2.2.5 --- Reverse transcription of HAV genomic RNA template and PCR --- p.43 / Chapter 2.2.6 --- Human β-actin gene PCR for the evaluation of shellfish homogenates --- p.45 / Chapter 2.2.7 --- Analysis of PCR products --- p.46 / Chapter 2.2.7.1 --- Agarose gel electrophoresis for the analysis of PCR products --- p.46 / Chapter 2.2.7.2 --- Dot blot hybridization for the confirmation of PCR products --- p.46 / Chapter 2.2.7.3 --- Southern blot hybridization for the confirmation of PCR products --- p.47 / Chapter 2.2.7.4 --- 5'-end DNA labelling of oligonucleotide probe --- p.47 / Chapter 2.2.7.5 --- Hybridization in sodium chloride / sodium citrate --- p.48 / Chapter Chapter 3- --- Results / Chapter 3.1 --- Epidemiology of acute HAV infection in Hong Kong --- p.52 / Chapter 3.2 --- Synthesis and yields of oligonucleotide primers --- p.54 / Chapter 3.3 --- Development of reverse-transcription polymerase chain reaction (RT-PCR) for HAV --- p.55 / Chapter 3.4 --- Sampling of shellfish from different markets in Hong Kong --- p.59 / Chapter 3.5 --- Quantitation of HAV RNA in stock virus preparations --- p.62 / Chapter 3.6 --- Comparison of RNA extraction methods and the detection limit of the established RT-PCR method for HAV --- p.62 / Chapter 3.7 --- Specificity of the RT-PCR in combination with virion capture method for the detection of HAV --- p.65 / Chapter 3.8 --- Detection of HAV RNA by RT-PCR in shellfish in Hong Kong / Chapter Chapter 4- --- Discussion / Chapter 4.1 --- Epidemiology of acute HAV infection in Hong Kong --- p.76 / Chapter 4.2 --- Development of RT-PCR method for the detection of HAV --- p.78 / Chapter 4.3 --- Evaluation of RNA extraction methods for the detection of HAV in shellfish sample by RT-PCR --- p.78 / Chapter 4.4 --- Application of the established RT-PCR method for the detection of HAV contamination in locally available shellfish --- p.79 / Chapter Chapter 5- --- References --- p.90 / Appendix I Figures of agarose gel electrophoresis of RT-PCR products for all samples (I1 -I23 ) --- p.101 / Appendix II Figures of dot-blot hybridization assay (II2 -II4 ) --- p.114
7

Purification and characterization of glutathione s-transferase from chironomidae larvae (red bloodworm).

January 2000 (has links)
by Yuen Wai Keung. / Thesis submitted in: December 1999. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2000. / Includes bibliographical references (leaves 99-112). / Abstracts in English and Chinese. / Acknowledgement --- p.i / Abstract --- p.ii / Abstract (Chinese Version) --- p.iv / Abbreviations --- p.vi / Table of Contents --- p.viii / Chapter chapter one --- introduction --- p.1 / Chapter 1.1 --- Glutathione S-transferase --- p.2 / Chapter 1.1.1 --- Introduction --- p.2 / Chapter 1.1.2 --- Classification of mammalian GST --- p.2 / Chapter 1.1.3 --- Classification of insect GST --- p.7 / Chapter 1.1.4 --- Substrate specificity --- p.11 / Chapter 1.2 --- The chironomidae --- p.13 / Chapter 1.2.1 --- Biology and life history of chironomidae --- p.13 / Chapter 1.3 --- Chironomidae larvae --- p.16 / Chapter 1.3.1 --- Bloodworm t --- p.6 / Chapter 1.3.2 --- Sources of chironomidae larvae --- p.17 / Chapter 1.4 --- Aim of research --- p.18 / Chapter chapter two --- materials and methods --- p.20 / Chapter 2.1 --- Screening of GST in different subcellular fractions --- p.21 / Chapter 2.1.1 --- Preparation of mitochondria --- p.21 / Chapter 2.1.2 --- Preparation of microsomes --- p.22 / Chapter 2.1.3 --- Preparation of cytosol --- p.22 / Chapter 2.2 --- Assay for GST activity --- p.23 / Chapter 2.2.1 --- Activity Units --- p.23 / Chapter 2.3 --- Protein assay --- p.23 / Chapter 2.4 --- Preparation of glutathione-affinity column --- p.25 / Chapter 2.5 --- Purification of cytosolic GSTs --- p.26 / Chapter 2.5.1 --- Preparation of cytosol --- p.26 / Chapter 2.5.2 --- Chromatography on Sephadex G25 --- p.26 / Chapter 2.5.3 --- Affinity Chromatography --- p.26 / Chapter 2.5.3.1 --- Specific elution of GSTs --- p.26 / Chapter 2.5.3.2 --- Non-specific elution of GSTs --- p.27 / Chapter 2.5.4 --- Fast Protein Liquid Chromatography with Mono Q --- p.27 / Chapter 2.6 --- Determination of molecular mass --- p.29 / Chapter 2.6.1 --- Subunit molecular mass --- p.29 / Chapter 2.6.2 --- Native molecular mass --- p.31 / Chapter 2.7 --- Isoelectric focusing PAGE --- p.31 / Chapter 2.8 --- Enzyme activities and kinetic studies --- p.34 / Chapter 2.8.1 --- Optimum pH --- p.34 / Chapter 2.8.2 --- Heat inactivation assay --- p.34 / Chapter 2.8.3 --- Km and Vmax --- p.34 / Chapter 2.8.4 --- Substrate specificity --- p.35 / Chapter 2.8.5 --- Glutathione peroxidase activity --- p.38 / Chapter 2.9 --- N-terminal amino acid sequence analysis --- p.39 / Chapter 2.9.1 --- Semidry electroblotting --- p.39 / Chapter 2.9.2 --- Staining of proteins on PVDF membrane --- p.40 / Chapter 2.9.3 --- N-terminal amino acid sequence analysis --- p.40 / Chapter 2.9.4 --- On-membrane deblocking of protein --- p.40 / Chapter 2.9.5 --- BLAST search --- p.41 / Chapter chapter three --- results --- p.42 / Chapter 3.1 --- Screening of GST in different subcellular fractions --- p.43 / Chapter 3.2 --- Purification of cytosolic GSTs by chromatography --- p.45 / Chapter 3.2.1 --- Sephadex G25 column --- p.45 / Chapter 3.2.2 --- GSH affinity column --- p.45 / Chapter 3.2.3 --- Mono-Q column --- p.45 / Chapter 3.3 --- Determination of molecular mass --- p.53 / Chapter 3.3.1 --- Subunit molecular mass --- p.53 / Chapter 3.3.2 --- Native molecular mass --- p.53 / Chapter 3.4 --- Isoelectric point determination --- p.53 / Chapter 3.5 --- Enzymes activities and kinetic studies --- p.57 / Chapter 3.5.1 --- Optimum pH --- p.57 / Chapter 3.5.2 --- Thermostability --- p.57 / Chapter 3.5.3 --- Km and Vmax --- p.57 / Chapter 3.5.4 --- Substrate specificity --- p.76 / Chapter 3.5.5 --- Glutathione peroxidase Activity --- p.76 / Chapter 3.6 --- N-terminal amino acid sequence analysis --- p.83 / Chapter chapter four --- discussion --- p.89 / Chapter 4.1 --- GST in different subcellular fractions --- p.90 / Chapter 4.2 --- Purification of cytosolic GST --- p.91 / Chapter 4.3 --- Physical properties --- p.93 / Chapter 4.3.1 --- Subunit molecular mass --- p.93 / Chapter 4.3.2 --- Native molecular mass --- p.93 / Chapter 4.3.3 --- Isoelectric point --- p.95 / Chapter 4.4 --- Kinetic properties --- p.94 / Chapter 4.4.1 --- Optimum pH --- p.94 / Chapter 4.4.2 --- Thermostability --- p.95 / Chapter 4.4.3 --- Km and Vmax --- p.95 / Chapter 4.4.4 --- Substrate specificity --- p.96 / Chapter 4.4.5 --- Glutathione peroxidase activity --- p.96 / Chapter 4.5 --- N-terminal amino acid sequence data --- p.97 / Chapter 4.6 --- Conclusion --- p.98 / references --- p.99
8

Studies on ribosome-inactivating proteins from momordica charantia.

January 1997 (has links)
by Tse Man Fai. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1997. / Includes bibliographical references (leaves 74-81). / ACKNOWLEDGMENTS --- p.I / ABSTRACT --- p.II / LIST OF ABBREVIATIONS --- p.III / TABLE OF CONTENTS --- p.1 / Chapter CHAPTER 1 --- INTRODUCTION --- p.2 / Chapter 1.1 --- rIbosome-inactivatIng proteins (RIPS) --- p.2 / Chapter 1.1.1 --- Classification of RIPs --- p.2 / Chapter 1.1.2 --- Distribution of RIPs --- p.6 / Chapter 1.1.3 --- Molecular biology of RIPs --- p.7 / Chapter 1.1.4 --- Physical and chemical properties of RIPs --- p.9 / Chapter 1.1.5 --- Enzymatic and translation-inhibitory activities --- p.12 / Chapter 1.1.6 --- RIP-based Immunotoxins --- p.16 / Chapter 1.2 --- MOMORDICA CHARANTIA and its RIBoosome-inactivating proteins (RIP) --- p.17 / Chapter 1.2.1 --- Momordica charantia --- p.17 / Chapter 1.2.2 --- Ribosome-inactivating proteins (RIPs) in Momordica charantia --- p.18 / Chapter 1.3 --- Objective of this study --- p.28 / Chapter CHAPTER 2 --- STUDY ON A NEW RIBOSOME-INACTIVATING PROTEIN (RIP) FROM MOMORDICA CHARANTIA SEEDS --- p.30 / Chapter 2.1 --- Introduction --- p.30 / Chapter 2.2 --- Materials and Methods --- p.33 / Chapter 2.2.1 --- Materials --- p.33 / Chapter 2.2.2 --- RIP isolation --- p.34 / Chapter 2.2.3 --- Characterization --- p.35 / Chapter 2.3 --- Results --- p.42 / Chapter 2.4 --- Discussion --- p.48 / Chapter CHAPTER 3 --- STUDY ON A NEW RIBOSOME-INACTIVATING PROTEIN (RIP) FROM MOMORDICA CHARANTIA FRUITS --- p.51 / Chapter 3.1 --- Introduction --- p.51 / Chapter 3.2 --- Materials and methods --- p.53 / Chapter 3.2.1 --- Materials --- p.53 / Chapter 3.2.2 --- RIP isolation --- p.54 / Chapter 3.2.3 --- Characterization --- p.56 / Chapter 3.3 --- Results --- p.56 / Chapter 3.4 --- Discussion --- p.62 / Chapter CHAPTER 4 --- GENERAL DISCUSSION AND CONCLUSION --- p.64 / Chapter 4.1 --- General discussion --- p.64 / Chapter 4.2 --- Conclusion --- p.72 / REFERENCES --- p.74
9

Purification, characterization and localization of cellulolytic enzymes produced by the straw mushroom, volvariella volvacea.

January 1996 (has links)
by Yijin Cai. / Thesis (Ph.D.)--Chinese University of Hong Kong, 1996. / Includes bibliographical references (leaves 185-207). / Introduction / Chapter 1.1 --- Biochemistry of cellulose degradation --- p.1 / Chapter 1.1.1 --- "Occurrence, distribution and structure of cellulose" --- p.1 / Chapter 1.1.2 --- Cellulose-degrading microorganisms --- p.3 / Chapter 1.1.2.1 --- Cellulolytic bacteria --- p.4 / Chapter 1.1.2.2 --- Cellulolytic fungi --- p.4 / Chapter 1.1.3 --- An overview of fungal cellulases --- p.4 / Chapter 1.1.3.1 --- Endoglucanase (EG) --- p.7 / Chapter 1.1.3.2 --- Cellobiohydrolase (CBH) --- p.16 / Chapter 1.1.3.3 --- β-Glucosidase (BGL) --- p.25 / Chapter 1.1.4 --- Synergism between the different components of the cellulolytic systems of filamentous fungi --- p.28 / Chapter 1.1.5 --- Molecular genetics of cellulases --- p.31 / Chapter 1.2 --- Secretion of cellulases by filamentous fungi --- p.32 / Chapter 1.2.1. --- Overview of enzyme secretion in filamentous fungi --- p.33 / Chapter 1.2.2 --- Glycosylation --- p.35 / Chapter 1.2.3 --- Protein secretion and the fungal cell wall --- p.37 / Chapter 1.2.4 --- Factors affecting protein secretion --- p.38 / Chapter 1.3 --- Volvariella volvacea --- p.39 / Chapter 1.4 --- Project aims --- p.43 / Materials and methods / Chapter 2.1 --- Organisms and culture conditions --- p.44 / Chapter 2.1.1 --- Basal medium --- p.44 / Chapter 2.1.2 --- Culture conditions for biomass and enzyme production on different carbon sources --- p.45 / Chapter 2.1.3 --- Culture conditions for large-scale enzyme production for purification --- p.45 / Chapter 2.1.4 --- Culture conditions for confocal microscopy --- p.46 / Chapter 2.1.5 --- Culture conditions for electron microscopy --- p.47 / Chapter 2.2 --- Mycelial extracts --- p.47 / Chapter 2.2.1 --- Large scale extraction --- p.47 / Chapter 2.2.2 --- Small scale extraction --- p.48 / Chapter 2.3 --- Enzyme purification --- p.48 / Chapter 2.3.1 --- Cell-associated enzymes (β-glucosidases) --- p.48 / Chapter 2.3.2 --- Extracellular enzymes --- p.50 / Chapter 2.3.2.1 --- Purification of cellulase complex --- p.50 / Chapter 2.3.2.2 --- Purification of CBH --- p.51 / Chapter 2.3.2.3 --- Purification of endoglucanase-III --- p.53 / Chapter 2.3.2.4 --- Partial purification of β-glucosidases --- p.55 / Chapter 2.3.3 --- Other purification methods --- p.56 / Chapter 2.3.3.1 --- FPLC Phenylsuperose hydrophobic interaction chromatography --- p.56 / Chapter 2.3.3.2 --- Affinity gel chromatography --- p.56 / Chapter 2.3.3.3 --- Isoelectric focusing by Rotorfor --- p.57 / Chapter 2.3.3.4 --- Preparative gel electrophoresis --- p.57 / Chapter 2.3.3.5 --- (NH4)2S04 Precipitation --- p.58 / Chapter 2.4 --- Electrophoresis --- p.59 / Chapter 2.4.1 --- Mini Protean-II system (BioRad) --- p.59 / Chapter 2.4.2 --- PhastGel system (Pharmacia) --- p.60 / Chapter 2.5 --- Enzyme assays --- p.61 / Chapter 2.5.1 --- β-Glucosidase --- p.61 / Chapter 2.5.2 --- Endoglucanase --- p.63 / Chapter 2.5.3 --- Cellobiohydrolase --- p.65 / Chapter 2.6 --- β-Glucosidase characterization studies --- p.66 / Chapter 2.6.1 --- pH optimum --- p.66 / Chapter 2.6.2 --- Temperature optimum --- p.66 / Chapter 2.6.3 --- Thermal stability --- p.66 / Chapter 2.6.4 --- Kinetic parameters --- p.67 / Chapter 2.6.5 --- Enzyme inhibitor studies --- p.67 / Chapter 2.6.6 --- Effect of lignin-derived phenolic monomers --- p.67 / Chapter 2.6.7 --- Substrate specificity towards p-nitrophenyl-linked glycosides --- p.67 / Chapter 2.6.8 --- "Substrate specificity towards different cellulosic substrates, mono- and disaccharides, hemicellulose, sugar alcohols and saponins" --- p.68 / Chapter 2.6.9 --- Cellulose-binding assay --- p.68 / Chapter 2.6.10 --- Effect of purified β-glucosidase on the production of glucose from crystalline cellulose and carboxymethylcellulose by Aspergillus niger cellulase --- p.69 / Chapter 2.7 --- Miscellaneous analytical methods --- p.69 / Chapter 2.7.1 --- Protein determination --- p.69 / Chapter 2.7.2 --- Determination of isoelectric points --- p.69 / Chapter 2.7.3 --- Activity staining of gels for cellulolytic enzyme activity --- p.70 / Chapter 2.7.4 --- Staining for glycoprotein --- p.71 / Chapter 2.7.5 --- Molecular weight determination --- p.71 / Chapter 2.8 --- "Production, purification and specificity of antibodies to β-glucosidases and EG-III" --- p.72 / Chapter 2.8.1 --- Antibodies to β-glucosidases --- p.72 / Chapter 2.8.2 --- Antibodies to EG-III --- p.74 / Chapter 2.9 --- Immunocytochemical studies --- p.75 / Chapter 2.9.1 --- Confocal laser scanning microscopy --- p.75 / Chapter 2.9.1.1 --- β-Glucosidases --- p.75 / Chapter 2.9.1.2 --- Endoglucanase-III --- p.75 / Chapter 2.9.2 --- Transmission electron microscopy --- p.76 / Chapter 2.9.3 --- Scanning electron microscopy --- p.77 / Chapter 2.10 --- Chemicals --- p.77 / Results / Chapter 3.1 --- "Effect of culture conditions on the growth of, and the production of cellulolytic enzymes, by V. volvacea" --- p.79 / Chapter 3.1.1 --- Growth --- p.79 / Chapter 3.1.2 --- Endoglucanases --- p.81 / Chapter 3.1.3 --- Cellobiohydrolase --- p.84 / Chapter 3.1.4 --- β-Glucosidase --- p.87 / Chapter 3.2 --- Purification of cellulolytic enzymes from V. volvacea --- p.92 / Chapter 3.2.1 --- Preliminary purification of V. volvacea extracellular cellulolytic enzymes --- p.92 / Chapter 3.2.1.1. --- (NH4)2SO4 precipitation --- p.92 / Chapter 3.2.1.2 --- Ultrafiltration --- p.94 / Chapter 3.2.1.3 --- Batch adsorption by anion exchanger --- p.94 / Chapter 3.2.1.4 --- Separation by column chromatography --- p.96 / Chapter 3.2.2 --- CBH enzymes …… --- p.102 / Chapter 3.2.3 --- Endoglucanase enzymes --- p.106 / Chapter 3.2.4 --- Cell-associated β-glucosidase enzymes --- p.113 / Chapter 3.2.5 --- Extracellular β-glucosidase enzymes --- p.120 / Chapter 3.3 --- Characterization of cell-associated β-glucosidases from V. volvacea --- p.122 / Chapter 3.3.1 --- Influence of pH and temperature --- p.122 / Chapter 3.3.2 --- Enzyme stability --- p.125 / Chapter 3.3.3 --- Kinetic parameters --- p.128 / Chapter 3.3.4 --- Enzyme inhibitors --- p.131 / Chapter 3.3.5 --- Substrate specificity --- p.137 / Chapter 3.3.6 --- Cellulose-binding and hydrolysing properties --- p.139 / Chapter 3.3.7 --- Molecular weights and isoelectric points --- p.142 / Chapter 3.4 --- Immunocytochemical studies on cellulolytic enzymes from V. volvacea --- p.146 / Chapter 3.4.1 --- Cell-associated β-glucosidase --- p.146 / Chapter 3.4.1.1 --- "Production, specificity and purification of polyclonal antibody" --- p.146 / Chapter 3.4.1.2. --- Localization --- p.151 / Chapter 3.4.1.3. --- Localization of cell-associated β-glucosidases by immuno- labelling --- p.151 / Chapter 3.4.2 --- Endoglucanase-III --- p.161 / Discussion / Chapter 4.1 --- Production --- p.163 / Chapter 4.2 --- Composition of cellulolytic enzyme system of V. volvacea --- p.168 / Chapter 4.3 --- Properties --- p.172 / Chapter 4.4 --- Localization --- p.179 / References --- p.185
10

Purification and characterization of monofunctional catalase in post-mitochondrial fractions from chironomid larvae (bloodworms).

January 2001 (has links)
Lai Chi-wai. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2001. / Includes bibliographical references (leaves 93-100). / Abstracts in English and Chinese. / ACKNOWLEDGEMENTS --- p.I / ABSTRACT --- p.II / 摘要 --- p.IV / ABBREVIATION --- p.VI / TABLE OF CONTENTS --- p.VII / LIST OF FIGURES --- p.XII / LIST OF TABLES --- p.XIV / Chapter CHAPTER 1 --- INTRODUCTION --- p.1 / Chapter 1.1 --- Catalases --- p.2 / Chapter 1.2 --- Classification of catalases --- p.3 / Chapter 1.2.1 --- Catalase peroxidase (HPI) --- p.3 / Chapter 1.2.2 --- Monofunctional catalases (HPII) --- p.6 / Chapter 1.2.2.1 --- NADPH in catalases --- p.9 / Chapter 1.2.3 --- Mn-catalases --- p.11 / Chapter 1.3 --- Sources and cytotoxic effects of hydrogen peroxide --- p.13 / Chapter 1.4 --- The Chironomidae --- p.14 / Chapter 1.4.1 --- Life cycle of Chironomidae --- p.14 / Chapter 1.4.2 --- Bloodworms --- p.18 / Chapter 1.4.3 --- Sources of bloodworms --- p.19 / Chapter 1.5 --- Aim of the project --- p.22 / Chapter 1.6 --- Application of the project --- p.22 / Chapter CHAPTER 2 --- MATERIALS AND METHODS --- p.24 / Chapter 2.1 --- Protein determination --- p.25 / Chapter 2.2 --- In vitro activity assays --- p.27 / Chapter 2.2.1 --- Catalase activity assay --- p.27 / Chapter 2.2.2 --- Peroxidase activity assay --- p.27 / Chapter 2.3 --- Screening of catalase in different subcellular fractions --- p.28 / Chapter 2.3.1 --- Preparation of mitochondrial fractions --- p.28 / Chapter 2.3.2 --- Preparation of microsomal fractions --- p.29 / Chapter 2.3.3 --- Preparation of cytosolic fractions --- p.29 / Chapter 2.3.4 --- Preparation of post-mitochondrial fractions --- p.29 / Chapter 2.4 --- Purification of post-mitochondrial catalase --- p.29 / Chapter 2.4.1 --- Preparation of post-mitochondrial fractions --- p.30 / Chapter 2.4.2 --- Ethanol-chloroform precipitation --- p.30 / Chapter 2.4.3 --- Affinity chromatography --- p.30 / Chapter 2.4.4 --- Cation exchange chromatography --- p.31 / Chapter 2.5 --- Molecular mass determination --- p.34 / Chapter 2.6 --- Isoelectric focusing --- p.39 / Chapter 2.7 --- Kinetic studies of the purified enzyme --- p.42 / Chapter 2.7.1 --- Optimal pH --- p.42 / Chapter 2.7.2 --- Thermal stability --- p.42 / Chapter 2.7.3 --- Km and Vmax --- p.42 / Chapter 2.7.4 --- Inhibition studies --- p.43 / Chapter 2.7.4.1 --- "3-amino-1,2,4-triazole" --- p.43 / Chapter 2.7.4.2 --- Potassium cyanide and sodium azide --- p.43 / Chapter 2.8 --- Spectroscopic analysis --- p.44 / Chapter 2.8.1 --- Native enzyme --- p.44 / Chapter 2.8.2 --- Denatured enzyme --- p.44 / Chapter 2.8.3 --- Determination of pyridine hemochrome --- p.44 / Chapter 2.9 --- N-terminal amino acid sequence analysis for blotted protein --- p.45 / Chapter 2.9.1 --- Semi-dry electroblotting --- p.45 / Chapter 2.9.2 --- Protein staining on PVDF membrane --- p.46 / Chapter 2.9.3 --- N-terminal amino acid sequence analysis --- p.46 / Chapter 2.9.4 --- N-terminal deblocking of protein bound on PVDF membrane… --- p.47 / Chapter 2.9.5 --- BLAST® search --- p.48 / Chapter CHAPTER 3 --- RESULTS --- p.49 / Chapter 3.1 --- Catalase in different sub-cellular fractions --- p.50 / Chapter 3.2 --- Purification of post-mitochondrial catalase --- p.51 / Chapter 3.2.1 --- Ethanol-chloroform precipitation --- p.51 / Chapter 3.2.2 --- Affinity chromatography --- p.51 / Chapter 3.2.3 --- Cation exchange chromatography --- p.52 / Chapter 3.3 --- Determination of molecular mass --- p.57 / Chapter 3.4 --- Determination of isoelectric point --- p.57 / Chapter 3.5 --- Kinetic studies of the catalase --- p.62 / Chapter 3.5.1 --- Optimal pH --- p.62 / Chapter 3.5.2 --- Thermal stability --- p.62 / Chapter 3.5.3 --- Km and Vmax --- p.65 / Chapter 3.5.4 --- Inhibition studies --- p.65 / Chapter 3.5.4.1 --- "3-amino-1,2,4-triazole" --- p.65 / Chapter 3.5.4.2 --- Potassium cyanide and sodium azide --- p.65 / Chapter 3.5.5 --- Catalase peroxidase activity --- p.66 / Chapter 3.6 --- Spectroscopic analysis --- p.73 / Chapter 3.6.1 --- Native enzyme --- p.73 / Chapter 3.6.2 --- Denatured enzyme --- p.73 / Chapter 3.6.2.1 --- Potassium cyanide --- p.73 / Chapter 3.6.2.2 --- Sodium azide --- p.73 / Chapter 3.6.3 --- Pyridine hemochrome characterization --- p.73 / Chapter 3.7 --- N-terminal amino acid sequence analysis --- p.79 / Chapter CHAPTER 4 --- DISCUSSION --- p.81 / Chapter 4.1 --- Subcellular locations of catalase in bloodworms --- p.82 / Chapter 4.2 --- Purification of post-mitochondrial catalase --- p.82 / Chapter 4.3 --- Physical properties of the purified enzyme --- p.84 / Chapter 4.3.1 --- Native and subunit molecular mass --- p.84 / Chapter 4.3.2 --- Isoelectric point --- p.85 / Chapter 4.4 --- Kinetic properties of the purified enzyme --- p.85 / Chapter 4.4.1 --- Optimal pH --- p.85 / Chapter 4.4.2 --- Thermal stability --- p.85 / Chapter 4.4.3 --- Km and Vmax --- p.87 / Chapter 4.4.4 --- Inhibition studies --- p.87 / Chapter 4.4.5 --- Catalase peroxidase activity --- p.87 / Chapter 4.5 --- Spectroscopic analysis --- p.88 / Chapter 4.5.1 --- Native and denatured enzyme --- p.88 / Chapter 4.5.2 --- Pyridine hemochrome characterization --- p.88 / Chapter 4.6 --- N-terminal amino acid analysis --- p.89 / Chapter 4.7 --- Conclusions --- p.89 / REFERENCES --- p.93

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