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1.
Front Psychol ; 15: 1371271, 2024.
Article in English | MEDLINE | ID: mdl-38873506

ABSTRACT

The concept of soft power has engendered lively discourse within the international community. The development of a nation's soft power frequently hinges on cultural communication and the promotion of language. This manuscript concentrates on Japan as a case study and undertakes an investigation of the methods it has employed to cultivate its soft power. To accomplish this objective, Japan's strategies for cultural communication and the promotion of the Japanese language are comprehensively examined. From the perspective of language planning, prestige planning of language and culture constitutes a crucial mode of cultural communication, whereas language education planning (or acquisition planning) is the primary method of language promotion. Japan has adeptly disseminated its culture overseas through cultural communication and language promotion. On one hand, it fashions a "cool culture" embodied by anime and manga to augment cultural appeal and amplify national image. On the other hand, it advances the Japanese language abroad by establishing supportive institutions, dispatching experts and volunteers, and creating online teaching materials. Building on Japan, this paper establishes a theoretical framework for the construction of soft power, employing the aforementioned two approaches as valuable guides for research on soft power.

2.
Materials (Basel) ; 17(10)2024 May 07.
Article in English | MEDLINE | ID: mdl-38793259

ABSTRACT

Magnesium (Mg)-matrix composites have excellent damping and electromagnetic shielding properties. However, the mismatch between their strength and toughness limits their wide application. The aim of this work is to overcome the strength-toughness mismatch by constructing micro- and nanostructures while maintaining the good functional properties of Mg-matrix composites. Electrophoretic deposition (EPD) was used to spread carbon nanotubes (CNTs) out evenly on a Mg foil matrix. After spark plasma sintering (SPS), the grain organisation was refined, and the interlayer bonding was strengthened by hot rolling deformation. Finally, the microstructure, mechanical properties, damping properties, and electromagnetic shielding properties of the composites were analysed. Compared with the pure Mg laminates, the tensile strength and elongation of the CNT/Mg laminates were increased by 6.4% and 108.4%, respectively, with the significant improvement in toughness resulting from the increase in energy required for crack propagation due to the laminate structure. When the total rolling deflection reaches 80%, the interlayer bond strength of the material is significantly increased, the grain is further refined, and the strength and elongation of the composite material reaches the optimum, with the tensile strength reaching 241.70 MPa and the elongation reaching 6.90%. The interlayer interface and grain refinement also affected the damping Mg and electromagnetic shielding effect of the composites. This work provides an experimental idea for the preparation of high-performance structure-function integrated Mg-based materials.

3.
J Microbiol Methods ; 215: 106861, 2023 12.
Article in English | MEDLINE | ID: mdl-38030086

ABSTRACT

As the most abundant biopolymer on earth, cellulose undergoes degradation by a diverse set of enzymes with varying specificities that act in synergism. An assay protocol was developed to detect and quantify activity of cellulose 1,4-ß-cellobiosidase (EC 3.2.1.91) in soil. The optimum pH and temperature for ß-cellobiosidase activity were approximately pH 5.5 and 60 °C, respectively. In the tested six soils, the Michaelis constants (Km) ranged from 0.08 to 0.51 mM, and maximum velocity (Vmax) ranged from 71.5 to 318.1 µmol kg soil-1 h-1. The temperature coefficient (Q10) ranged from 1.72 to 1.99 at non-denaturing temperatures from 10 to 50 °C, and the activation energy (Ea) ranged from 42.5 to 53.7 kJ mol-1. The assay procedure provided reproducible results with a coefficient of variance ≤4.7% and demonstrated a limit of quantification (LOQ) of 50.9 µmol p-nitrophenol release kg-1 soil h-1 for ß-cellobiosidase activity in soil. Notably, the developed assay protocol offers reproducibility and precision comparable to bench-scale assays while reducing costs associated with reagents, supplies, and labor.


Subject(s)
Cellulose 1,4-beta-Cellobiosidase , Cellulose , Cellulose/metabolism , Cellulose 1,4-beta-Cellobiosidase/metabolism , Reproducibility of Results , Temperature , Soil , Kinetics
4.
Front Psychol ; 14: 1191420, 2023.
Article in English | MEDLINE | ID: mdl-37901095

ABSTRACT

The development of locally developed English language teaching (ELT) materials is believed to be conducive to meeting the requirements of local language education policies and practices, and to enhance learners' agency. In China, in order to implement national educational policy of curriculum-based value education, many locally developed ELT materials have been recently developed. However, there is a paucity of empirical research concerning the actual effects of such materials in practice. This study presents an empirical study of a recently developed set of teaching materials in the context of curriculum-based value education by adopting an approach consisting of questionnaires and interviews to examine the attitudes and experiences of users of these materials. The findings revealed a range of challenges in the use of these materials, including issues related to language and content of the materials, the integration of ideological and value elements, and the development of multi-dimensional teaching materials. The article then proposes possible solutions from the perspectives of optimizing the writing community, carefully selecting teaching materials, innovating the integration of ideological and political elements, and improving the development of multi-dimensional teaching materials. A framework for the evaluation of locally developed ELT materials is also proposed, with the intention of offering a useful benchmark for enhancing the development of such materials.

5.
Research (Wash D C) ; 6: 0157, 2023.
Article in English | MEDLINE | ID: mdl-37292515

ABSTRACT

Flexible full-textile pressure sensor is able to integrate with clothing directly, which has drawn extensive attention from scholars recently. But the realization of flexible full-textile pressure sensor with high sensitivity, wide detection range, and long working life remains challenge. Complex recognition tasks necessitate intricate sensor arrays that require extensive data processing and are susceptible to damage. The human skin is capable of interpreting tactile signals, such as sliding, by encoding pressure changes and performing complex perceptual tasks. Inspired by the skin, we have developed a simple dip-and-dry approach to fabricate a full-textile pressure sensor with signal transmission layers, protective layers, and sensing layers. The sensor achieves high sensitivity (2.16 kPa-1), ultrawide detection range (0 to 155.485 kPa), impressive mechanical stability of 1 million loading/unloading cycles without fatigue, and low material cost. The signal transmission layers that collect local signals enable real-world complicated task recognition through one single sensor. We developed an artificial Internet of Things system utilizing a single sensor, which successfully achieved high accuracy in 4 tasks, including handwriting digit recognition and human activity recognition. The results demonstrate that skin-inspired full-textile sensor paves a promising route toward the development of electronic textiles with important potential in real-world applications, including human-machine interaction and human activity detection.

6.
Biomed Pharmacother ; 151: 113080, 2022 Jul.
Article in English | MEDLINE | ID: mdl-35561427

ABSTRACT

BACKGROUND: The global prevalence of inflammatory bowel disease (IBD) is increasing, and mucosal healing is the preferred treatment target of IBD. Sodium (aS,9 R)- 3-hydroxy-16,17-dimethoxy-15-oxidotricyclo[12.3.1.12,6]nonadeca-1(18),2,4,6(19),14,16-hexene-9-yl sulfate hydrate (SDH) is a novel diarylheptane compound, which is designed to treat IBD. Hence, we investigated the potent therapeutic activity of SDH against IBD and explored the underlying mechanisms, and determined if SDH is a safe and well-tolerated oral therapeutic for IBD treatment. METHODS: We characterized its therapeutic properties in vitro and in vivo using Caco-2 cell monolayer and dextran sodium sulfate (DSS)- or 2,4,6-trinitro-benzene sulfonic acid (TNBS)-induced colitis models. We conducted nonclinical toxicology and safety pharmacology research, including general toxicity, toxicokinetics, pharmacokinetics, metabolism and plasma protein binding, cardiovascular safety pharmacology, central nervous system safety pharmacology, respiratory safety pharmacology, fertility and early embryonic development toxicity, reverse mutation assay, chromosomal aberration assay and micronucleus test. RESULTS: The results showed that SDH promoted expression of tight junction proteins, and protected the integrity and permeability of the epithelial barrier in both cell and animal models. Moreover, lower doses of SDH showed the similar or better efficacy than cyclosporine A (CsA) and mesalazine in DSS- or TNBS-induced colitis animals. Furthermore, our results identified that SDH has satisfactory safety in these studies we tested. In summary, SDH restored the epithelial barrier through tight junction proteins and was expected to be a novel therapeutic agent for the treatment of IBD.


Subject(s)
Colitis , Inflammatory Bowel Diseases , Animals , Caco-2 Cells , Colitis/chemically induced , Colitis/drug therapy , Colitis/metabolism , Colon/metabolism , Disease Models, Animal , Humans , Inflammatory Bowel Diseases/drug therapy , Inflammatory Bowel Diseases/metabolism , Intestinal Mucosa/metabolism , Mice , Mice, Inbred C57BL , Tight Junction Proteins/metabolism , Tight Junctions/metabolism
7.
Br J Pharmacol ; 178(3): 636-653, 2021 02.
Article in English | MEDLINE | ID: mdl-33140855

ABSTRACT

BACKGROUND AND PURPOSE: Psoriasis is a chronic immune-mediated inflammatory skin disease that easily recurs and is difficult to cure. DGT is a novel synthetic heterocyclic diterpenoid, whose structure has not been previously reported. We have investigated the action of DGT against psoriasis, specifically the hyperproliferation of epidermal keratinocytes, angiogenesis and pathogenic inflammatory responses. EXPERIMENTAL APPROACH: We investigated its pharmacokinetics in skin after topical administration. We characterized its pharmacological actions in vitro and in vivo using cell proliferation assay, cell apoptosis assay, diethylstilbestrol-induced mouse vaginal epithelial cell mitosis model, tube formation assay, cell migration assay, chick embryonic chorioallantoic membrane (CAM) assay, histological, flow cytometric analysis and imiquimod (IMQ)-induced psoriasis-like model. KEY RESULTS: DGT was found to be mainly distributed in the epidermis and dermis, which indicated that DGT was suitable as a topical treatment. DGT inhibited cell proliferation and induced apoptotic cell death of keratinocytes in vitro and in vivo. Moreover, DGT inhibited endothelial cell proliferation, tube formation and migration of in vitro angiogenesis, as well as in vivo CAM angiogenesis. In an IMQ-induced psoriasis-like skin inflammation murine model, topical application of DGT ameliorated keratinocyte proliferation and inflammatory response, especially in IL-17-related psoriasiform dermatitis. Furthermore, our results demonstrated that DGT prevented these pathological processes of psoriasis through suppression of STAT3 phosphorylation. CONCLUSION AND IMPLICATIONS: DGT has great potential as a novel therapeutic agent for the treatment of psoriatic skin disease.


Subject(s)
Diterpenes , Psoriasis , Animals , Disease Models, Animal , Diterpenes/pharmacology , Female , Imiquimod/metabolism , Imiquimod/toxicity , Keratinocytes , Mice , Mice, Inbred BALB C , Phosphorylation , Psoriasis/chemically induced , Psoriasis/drug therapy , Psoriasis/metabolism , Skin/metabolism
8.
Ecotoxicol Environ Saf ; 202: 110950, 2020 Oct 01.
Article in English | MEDLINE | ID: mdl-32800226

ABSTRACT

Human exposure to methylmercury (MeHg) through rice consumption is raising health concerns. It has long been recognized that MeHg found in rice grain predominately originated from paddy soil. Anaerobic conditions in paddy fields promote Hg methylation, potentially leading to high MeHg concentrations in rice grain. Understanding the transformation and migration of Hg in the rice paddy system, as well as the effects of farming activities, are keys to assessing risks and developing potential mitigation strategies. Therefore, this review examines the current state of knowledge on: 1) sources of Hg in paddy fields; 2) how MeHg and inorganic Hg (IHg) are transformed (including abiotic and biotic processes); 3) how IHg and MeHg enter and translocate in rice plants; and 4) how regular farming activities (including the application of fertilizer, cultivation methods, choice of cultivar), affect Hg cycling in the paddy field system. Current issues and controversies on Hg transformation and migration in the paddy field system are also discussed.


Subject(s)
Crop Production/methods , Environmental Monitoring/methods , Mercury/analysis , Methylmercury Compounds/analysis , Oryza/drug effects , Soil Pollutants/analysis , Fertilizers/analysis , Humans , Mercury/metabolism , Methylmercury Compounds/metabolism , Oryza/growth & development , Oryza/metabolism , Soil/chemistry , Soil Pollutants/metabolism
9.
Ecotoxicol Environ Saf ; 150: 116-122, 2018 Apr 15.
Article in English | MEDLINE | ID: mdl-29272715

ABSTRACT

High levels of mercury (Hg), especially methylmercury (MeHg), in rice is of concern due to its potential of entering food chain and the high toxicity to human. The level and form of Hg in rice could be influenced by fertilizers and other soil amendments. Studies were conducted to evaluate the effect of 24 years application of chemical fertilizers and organic amendments on total Hg (THg) and MeHg and their translocation in soil, plants, and rice grain. All treatments led to significantly higher concentrations of MeHg in grain than those from the untreated control. Of nine treatments tested, chemical fertilizers combining with returning rice straw (NPK1+S) led to highest MeHg concentration in grain and soil; while the nitrogen and potassium (NK) treatment led to significantly higher THg in grain. Concentrations of soil MeHg were significantly correlated with THg in soil (r = 0.59***) and MeHg in grain (r = 0.48***). Calcium superphosphate negatively affected plant bioavailability of soil Hg. MeHg concentration in rice was heavily influenced by soil Hg levels. Phosphorus fertilizer was a main source contributing to soil THg, while returning rice straw to the field contributed significantly to MeHg in soil and rice grain. As a result, caution should be exercised in soil treatment or when utilizing Hg-contaminated soils to produce rice for human consumption. Strategic management of rice straw and phosphorus fertilizer could be effective strategies of lowering soil Hg, which would ultimately lower MeHg in rice and the risk of Hg entering food chain.


Subject(s)
Fertilizers/analysis , Mercury/analysis , Methylmercury Compounds/analysis , Oryza/drug effects , Soil Pollutants/analysis , Soil/chemistry , Biological Availability , China , Environmental Monitoring , Food Chain , Humans , Organic Agriculture , Oryza/chemistry
10.
J Environ Sci Health B ; 52(5): 298-305, 2017 May 04.
Article in English | MEDLINE | ID: mdl-28277084

ABSTRACT

Annually, millions pounds of antibiotics are released unmetabolized into environment along with animal wastes. Accumulation of antibiotics in soils could potentially induce the persistence of antibiotic resistant bacteria. Antibiotics such as tetracyclines and tetracycline-resistant bacteria have been previously detected in fields fertilized with animal manure. However, little is known about the accumulation of tetracyclines and the development of tetracycline resistance in semi-arid soils. Here we demonstrate that continuous land application with swine effluent, containing trace amounts of chlortetracycline, does not necessarily induce tetracycline resistance in soil bacteria. Based on the testing of more than 3,000 bacteria isolated from the amended soils, we found no significant increase in the occurrence and level of chlortetracycline resistant bacteria in soils after 15 years of continuous swine effluent fertilization. To account for a possible transfer of tetracycline-resistant bacteria originated from the swine effluent to soils, we analyzed two commonly found tetracycline resistant genes, tet(O) and tet(M), in the swine effluent and fertilized soils. Both genes were present in the swine effluent, however, they were not detectable in soils applied with swine effluent. Our data demonstrate that agronomic application of manure from antibiotic treated swine effluent does not necessarily result in the development of antibiotic bacterial resistance in soils. Apparently, concentrations of chlortetracycline present in manure are not significant enough to induce the development of antibiotic bacterial resistance.


Subject(s)
Bacteria/drug effects , Manure/microbiology , Soil Microbiology , Tetracycline Resistance/drug effects , Agriculture , Animals , Anti-Bacterial Agents/pharmacology , Chlortetracycline/analysis , Chlortetracycline/pharmacology , Fertilizers , Microbial Sensitivity Tests , Oklahoma , Soil Pollutants/analysis , Swine , Tetracycline/pharmacology , Tetracyclines/pharmacology
11.
J Microbiol Methods ; 133: 32-34, 2017 02.
Article in English | MEDLINE | ID: mdl-28003129

ABSTRACT

Data interpretation and comparison in enzyme assays can be challenging because of the complex nature of the environment and variations in methods employed. This letter provides an overview of common enzyme assays, the need for methods standardization, and solutions addressing some of the concerns in microplate fluorimetric assay approaches.


Subject(s)
Enzyme Assays/standards , Soil/chemistry , Fluorometry , Sensitivity and Specificity
12.
Molecules ; 21(4): 526, 2016 Apr 21.
Article in English | MEDLINE | ID: mdl-27110753

ABSTRACT

Sustained monoculture often leads to a decline in soil quality, in particular to the build-up of pathogen populations, a problem that is conventionally addressed by the use of either fungicide and/or soil fumigation. This practice is no longer considered to be either environmentally sustainable or safe. While the application of organic fertilizer is seen as a means of combating declining soil fertility, it has also been suggested as providing some control over certain soil-borne plant pathogens. Here, a greenhouse comparison was made of the Fusarium wilt control efficacy of various treatments given to a soil in which chrysanthemum had been produced continuously for many years. The treatments comprised the fungicide carbendazim (MBC), the soil fumigant dazomet (DAZ), the incorporation of a Paenibacillus polymyxa SQR21 (P. polymyxa SQR21, fungal antagonist) enhanced bio-organic fertilizer (BOF), and applications of BOF combined with either MBC or DAZ. Data suggest that all the treatments evaluated show good control over Fusarium wilt. The MBC and DAZ treatments were effective in suppressing the disease, but led to significant decrease in urease activity and no enhancement of catalase activity in the rhizosphere soils. BOF including treatments showed significant enhancement in soil enzyme activities and microbial communities compared to the MBC and DAZ, evidenced by differences in bacterial/fungi (B/F) ratios, Shannon-Wiener indexes and urease, catalase and sucrase activities in the rhizosphere soil of chrysanthemum. Of all the treatments evaluated, DAZ/BOF application not only greatly suppressed Fusarium wilt and enhanced soil enzyme activities and microbial communities but also promoted the quality of chrysanthemum obviously. Our findings suggest that combined BOF with DAZ could more effectively control Fusarium wilt disease of chrysanthemum.


Subject(s)
Benzimidazoles/pharmacology , Carbamates/pharmacology , Chrysanthemum/microbiology , Fertilizers/microbiology , Fusarium/drug effects , Paenibacillus/growth & development , Plant Diseases/prevention & control , Thiadiazines/pharmacology , Chrysanthemum/enzymology , Fumigation/methods , Fungicides, Industrial/pharmacology , Greenhouse Effect , Plant Diseases/microbiology , Plant Roots/enzymology , Rhizosphere , Soil/chemistry , Soil Microbiology
13.
PLoS One ; 8(4): e61461, 2013.
Article in English | MEDLINE | ID: mdl-23637838

ABSTRACT

Monoculture causes nutrient losses and leads to declines in soil fertility and biomass production over successive cultivation. The rhizosphere, a zone of usually high microbial activities and clearly distinct from bulk soil, is defined as the volume of soil around living roots and influenced by root activities. Here we investigated enzyme activities and microbial biomass in the rhizosphere under different tree compositions. Six treatments with poplar, willow, and alder mono- or mixed seedlings were grown in rhizoboxes. Enzyme activities associated with nitrogen cycling and microbial biomass were measured in all rhizosphere and bulk soils. Both enzyme activities and microbial biomass in the rhizosphere differed significantly tree compositions. Microbial biomass contents were more sensitive to the changes of the rhizosphere environment than enzyme activities. Tree species coexistence did not consistently increase tested enzyme activities and microbial biomass, but varied depending on the complementarities of species traits. In general, impacts of tree species and coexistence were more pronounced on microbial composition than total biomass, evidenced by differences in microbial biomass C/N ratios stratified across the rhizosphere soils. Compared to poplar clone monoculture, other tree species addition obviously increased rhizosphere urease activity, but greatly reduced rhizosphere L-asparaginase activity. Poplar growth was enhanced only when coexisted with alder. Our results suggested that a highly productive or keystone plant species in a community had greater influence over soil functions than the contribution of diversity.


Subject(s)
Biomass , Rhizosphere , Trees/growth & development , Agriculture , Alnus/enzymology , Alnus/growth & development , Asparaginase/metabolism , Carbon/metabolism , Nitrogen/metabolism , Nitrogen Cycle , Peptide Hydrolases/metabolism , Plant Roots/growth & development , Populus , Salix/enzymology , Salix/growth & development , Soil Microbiology , Trees/enzymology , Urease/metabolism
14.
Environ Sci Pollut Res Int ; 20(2): 976-86, 2013 Feb.
Article in English | MEDLINE | ID: mdl-22802116

ABSTRACT

Polycyclic aromatic hydrocarbon (PAH) and metal-polluted sites caused by abandoned coking plants are receiving wide attention. To address the associated environmental concerns, innovative remediation technologies are urgently needed. This study was initiated to investigate the feasibility of a cleanup strategy that employed an initial phase, using methyl-ß-cyclodextrin (MCD) solution to enhance ex situ soil washing for extracting PAHs and metals simultaneously, followed by the addition of PAH-degrading bacteria (Paracoccus sp. strain HPD-2) and supplemental nutrients to treat the residual soil-bound PAHs. Elevated temperature (50 °C) in combination with ultrasonication (35 kHz, 30 min) at 100 g MCD L(-1) was effective in extracting PAHs and metals to assist soil washing; 93 % of total PAHs, 72 % of Cd, 78 % of Ni, 93 % of Zn, 84 % of Cr, and 68 % of Pb were removed from soil after three successive washing cycles. Treating the residual soil-bound PAHs for 20 weeks led to maximum biodegradation rates of 34, 45, 36, and 32 % of the remaining total PAHs, 3-ring PAHs, 4-ring PAHs, and 5(+6)-ring PAHs after washing procedure, respectively. Based on BIOLOG Ecoplate assay, the combined treatment at least partially restored microbiological functions in the contaminated soil. The ex situ cleanup strategy through MCD-enhanced soil washing followed by microbial augmentation can be effective in remediating PAH and metal-contaminated soil.


Subject(s)
Metals/metabolism , Polycyclic Aromatic Hydrocarbons/metabolism , Soil Microbiology , Soil Pollutants/metabolism , Biodegradation, Environmental , Metals/isolation & purification , Paracoccus/metabolism , Ultrasonics/methods , beta-Cyclodextrins
15.
J Tradit Chin Med ; 29(3): 211-5, 2009 Sep.
Article in English | MEDLINE | ID: mdl-19894388

ABSTRACT

OBJECTIVE: To evaluate the therapeutic effects and safety of the XIA's No.1 Sleeping Prescription for the treatment of insomnia of the deficiency type. METHODS: 120 cases conformed to the diagnostic criteria of the Chinese Classification of Mental Disorders-Version 3 (CCMD-3) and were diagnosed as having insomnia of the deficiency type were divided randomly into a treatment group and a control group, 60 cases in each group. The treatment group was treated with the XIA's No. 1 Sleeping Prescription, while the control group was given estazolam (1 mg) for 6 weeks. The Athens Insomnia Scale (AIS) was used to evaluate the clinical therapeutic effects, while the treatment emergent symptom scale (TESS) was used to evaluate adverse reactions. RESULTS: The total effective rate of the treatment group (80%) was higher than that of the control group (70%), but with no significant difference (P > 0.05). The effective rate for long-term insomnia was 77.8% in the treatment group and 52.4% in the control group, with a significant difference between the two groups (P < 0.05). The adverse reactions shown in the treatment group were obviously fewer and milder than those in the control group. CONCLUSION: The XIA's No. 1 Sleeping Prescription is effective for insomnia of the deficiency type and with no obvious toxic side effects.


Subject(s)
Medicine, Chinese Traditional , Sleep Initiation and Maintenance Disorders/drug therapy , Sleep/drug effects , Adult , Anti-Anxiety Agents/therapeutic use , Chi-Square Distribution , Estazolam/therapeutic use , Female , Humans , Male , Middle Aged , Quality of Life , Sleep Initiation and Maintenance Disorders/physiopathology , Treatment Outcome , Young Adult
16.
Appl Biochem Biotechnol ; 142(1): 81-94, 2007 Jul.
Article in English | MEDLINE | ID: mdl-18025571

ABSTRACT

Trichoderma is one of the most promising biocontrol agents against plant fungal diseases. In this study, a transgenic strain of Trichoderma atroviride was characterized. The transgenic strain contains an endochitinase gene (ThEn-42) driven by the cellulase promoter cbh1 of T. reesei for overexpression of ThEn-42. The culture filtrates of the transformant and the parental strain grown in eight different media were evaluated for chitinase and antifungal enzyme production based on activity gels, protein profiles, and antifungal activities. Results demonstrated that chitinases are important components and synergistic interactions play a key role in the antagonistic action of T. atroviride. Moreover, altering medium nutrient concentration and composition led to enhanced production of antifungal enzymes, a potential strategy for mass production. Two of the culture filtrates contained almost pure endochitinase, and could be excellent commercial sources for this enzyme. Several culture filtrates were highly antifungal. Two filtrates were so effective in biocontrol of a fungal pathogen, Penicillium digitatum, that they not only inhibited spore germination but destroyed the spores completely when 20 microl of culture filtrate (corresponding to approximately 104 microg of total protein) was applied in a total volume of 150 microl (approximately 0.7 mg protein ml(-1)).


Subject(s)
Biotechnology/methods , Trichoderma/metabolism , Antifungal Agents/chemistry , Chitinases/chemistry , Culture Media/metabolism , Gene Expression Regulation, Fungal , Genetic Techniques , Models, Genetic , Pest Control, Biological , Plant Diseases , Polymerase Chain Reaction , Proteins/chemistry , Transgenes
17.
Article in English | MEDLINE | ID: mdl-14747092

ABSTRACT

Ab initio calculations are reported for three of four possible conformers of 1,3-dichloropropane. The fourth conformer, with Cs symmetry, has a predicted enthalpy difference of more than 1500 cm(-1) from the most stable conformer from each calculation regardless of the basis set used, so there is little chance of observing it. Thus, there is no evidence in the infrared or Raman spectrum of the presence of a fourth conformer. The order of stability given by the ab initio calculations is C2(GG)>C1(AG)>C2v(AA)>Cs(GG'), where A indicates the anti form for one of the CH2Cl groups and G indicates the gauche conformation for the other CH2Cl group relative to the plane of the carbon atoms. Almost every band observed can be confidently assigned to one or another of the conformers. Many observed bands proved to be of a composite nature, with several nearly coincident vibrations of different conformers contributing to the band contour. Nonetheless, a complete assignment of fundamentals is possible for the most stable C2 conformer, and 5 of the fundamentals of the C2v conformer and 13 those of the C1 conformer can be confidently assigned.


Subject(s)
Propane/analogs & derivatives , Propane/chemistry , Molecular Conformation , Spectrophotometry, Infrared , Spectrum Analysis, Raman , Temperature
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