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文章
Karim Solaimani* and Fatemeh Shokrian
Abstract: Environmental change and socio-economic pressure are expected to have significant impacts on Northern Alborz vegetation, particularly along ecotone such as the treeline. Remote sensing may be well suited to monitoring recent changes across the treeline because it captures integrated changes of all vegetation life forms over large spatial extents. This research examines treeline vegetation composition and change along the Nojmeh treeline using a high resolution, ETM+ 2000. In this paper we investigate the use of satellite data to produce a classification of a treeline ecotone in Northern Alborz Mountains which has supported the field investigation as ground truth data collected in the summers from 2008 to 2010. The maximum correlation is related to the Bands 3 and 4 of Landsat ETM+ with shrubs canopy cover that indicated in r of 0.34 and 0.37 respectively. The maximum rate of correlation in respect to the indices were recognized for the vegetation cover of moisture stress index (MSI) for forbs cover (r= 0.62). The ratio vegetation index (RVI) for grasses cover was indicated (r= 0.53). In conclusion, the results are specified that the ETM+ sensor is the significant data with the elevated competence to discrimination of ecotone using vegetation indices.[...] Read More.
Keywords: ETM+, classification, ecotone, treeline, Alborz, Iran.
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文章
Bin Li, Rongrong Yu, Qiaomei Tang, Ting Su, Xiaoling Chen, Bo Zhu, Yanli Wang, Guanlin Xie and Guochang Sun*
Abstract: The potential of biofilm formation of 16 Paenibacillus strains and their inhibitory effect against bacterial wilt of tomato seedlings were examined in this study. The crystal violet assay indicated that all strains of Paenibacillus except strain MB02-1202 formed biofilm after 96 and 144 h of incubation while there was not significant difference in biofilm formation between strains of Paenibacillus polymyxa and strains of Paenibacillus macerans. However, the increase level of biofilm formation was associated with the increase of the incubation time and the initial inoculum density. In addition, all Paenibacillus strains except strain MB02-428 reduced wilt incidence in tomato seedlings inoculated with Ralstonia solanacearum while the cell numbers of R. solanacearum in rhizosphere soil was reduced by all Paenibacillus strains compared to the pathogen control. In general, most strains of Paenibacillus were able to both form biofilm and protect tomato seedlings from bacterial wilt, indicating that biofilm formation may play an important role in the biocontrol of Paenibacillus. This is first study regarding the relationship between in vitro biofilm formation ability of Paenibacillus strains and their inhibitory activity against R. solanacearum.[...] Read More.
Keywords: Biofilm, Paenibacillus, Ralstonia solanacearum, tomato.
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文章
Boualleg C., Kaouachi N., Seridi M., Ternango S. and Bensouilah M. A.
Abstract: A parasitic copepods study of Algerian teleost fish, report 25 copepod species belonging to eight families harvested from the gills of 14 fish species. The analysis of species richness according to some ecological, biological and taxonomical variables (Diet, Displacement, Way of life, Family) of the whole of hosts are reported in this study, the differences between mean specific richness (MSR) of all variables is statically significant according to Kruskal-Walis test using sigma stat software. Parasitic specificity is discussed, infestation parameters were described.[...] Read More.
Keywords: Gulf of Annaba, copepods, species richness, parasitic indices, parasitic ecology, teleost fishes.
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文章
Congbin Yao, Caixia Zhu, XueYin Pan, Xiuguo Hua and Congli Yuan*
Abstract: The genus Bartonella is comprised of 20 species and subspecies, in which 10 species are responsible for human infections. The identification of the causative agent of cat-scratch disease, bacillary angiomatosis, urban trench fever, and Carrion's disease has raised the emerging medical importance of Bartonella spp. This article provides an overview of bartonellosis with emphasis on its prevalence in China.[...] Read More.
Keywords: Bartonella, cat-scratch disease, wild animal, prevalence.
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Ana Niurka Hernández-Lauzardo*, Miguel Gerardo Velázquez-del Valle and María Guadalupe Guerra-Sánchez
Abstract: Chitosan is a deacetylated derivative of chitin, consisting mainly of glucosamine units, commercially obtained from crustacean waste. This natural compound is biodegradable and nontoxic and has diverse applications in agriculture, among which highlights the control of fungal diseases in crops of agricultural interest. This review focuses on some basic studies about the mode of action and the effect of chitosan on different phytopathogens fungi. In general, it is known that molecules of this polymer can act on extracellular (plasma membrane) and intracellular level (penetration of chitosan into the fungal cell). The study of the effect of chitosan on different phytopathogens fungi evidence that the response is variable; in some investigations, it was found that the spores are more sensitive than hyphae to the application of chitosan. Even though the progress in understanding the mode of action of this polymer and the various effects that can cause damage are known, it is necessary to carry out more studies about the biological activity of these molecules to propose better control strategies of the phytopathogens fungi.[...] Read More.
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Ramesh C. Kasana
Abstract: The environmental conditions on planet earth are extremely diverse, with enormous variations in pressure, pH, temperature and salt concentration. All these environments are inhabited by living organisms, particularly microorganisms which have adapted to the different extremes of environments. Among various extreme environments, low temperature is very common both in natural and man-made environments. Low temperature environment is a source for the isolation of cold adapted enzymes of commercial and industrial importance. In the recent past, metagenomics have been employed as a powerful approach for the isolation of novel genes, enzymes and bioactive molecules from the yet to be cultured component of microbial communities prevailing in various environments.[...] Read More.
Keywords: Metagenomics, cold environment, microorganism, enzyme.
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文章
Short Communication
Abstract: Q fever, caused by COXIELLA BURNETII, is a worldwide zoonosis that affects not wild animals but domestic animals throughout the world, except in New Zealand. Domestic ruminants are considered to be a major infection source of Q fever in humans. However, few studies on the prevalence of Q fever in humans or animals in Korea have been conducted. Thus, the aim of this study was to investigate the seroprevalence of Q fever in meat cattle and deer. Blood samples were collected from 1634 ruminants: 1000 cattle, 604 wapiti, and 30 sika deer. The blood samples were analyzed with CHEKIT Q fever ELISA kits. Thirteen of 1000 (1.3%) cattle, 10 of 604 (about 1.7%) wapiti, and 0 of 30 (0%) sika deer had antibodies against C. BURNETII. The prevalence of Q fever in this study was quite low. However, the public health implications of these findings are important, because they indicate that seropositive animals that are asymptomatic may be shedding C. BURNETII consistently. This condition could increase the risk of Q fever infection in Korea, especially because many Koreans habitually consume raw meat and drink deer blood.[...] Read More.
Keywords: Q fever, Coxiella burnetii, cattle, deer.
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文章
Zahedi, F., Heydari Nasrabadi, M.*, Tajabadi Ebrahimi, M. and Aboutalebi, H.
Abstract: The benefits of probiotic microorganisms have been tested in several studies and they show many positive effects on human health like reduction of serum cholesterol, stimulation of immune system and prevention or treatment of human infections. This study has shown the activity of Lactobacillus brevis and Lactobacillus plantarum isolated from Iranian traditional cheese on cutaneous wound and describes the difference in healing activity between these two Lactobacilli. Some strains of Lactobacillus isolated from traditional dairy products of Iran were investigated for exopolysaccharide (EPS) production using the phenol-sulfuric acid method. L. brevis and L. plantarum were selected because they have high exopolysaccharide (EPS) production. A full-thickness wound (1.5 × 1.5 cm) was made on the back of each rat (45 rats in 4 groups). Two groups, experimental 1 and experimental 2, were treated by L. brevis, and L. plantarum that were added to eucerin. A control group was treated with eucerin and a negative-control group, additionally, did not receive anything. On days 1, 3, 7, 14 and 21, the rats were killed and wound tissue samples were collected for histological and statistical studies. The percentage of wound healing and inflammation in the experimental groups on day 21, when compared with the control and negative control groups, were significant (p≤0.05). In contrast to the control and negative-control groups, the number of neutrophils in the experimental groups was reduced in the later phase of wound healing. The current study showed a significant reduction in inflammation and an acceleration of wound healing in wounds treated with Lactobacilli as compared to the control and negative control groups. Further studies are required to develop a mechanism of L. brevis and L. plantarum during wound healing.[...] Read More.
Keywords: Cutaneous wound, exopolysaccharide, Lactobacillus brevis, Lactobacillus plantarum.
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Anna Ilyina*, Anita J. Casas-Reyes, Karla M. Gregorio-Jauregui, Erika Nava-Reyna, Jose L. Martinez-Hernandez, Nagamani Balagurusamy, Federico Cerda-Ramirez and Yolanda Garza-Garcia
Abstract: The present study focuses on the improvement of limitations of the bioluminescent ATP assay. An attempt was made to improve on the following: non-selective detection, limited cell population density quantification, and to distinguish between bioluminescent noises data and cell ATP, as a suitable technique for coliforms and ESCHERICHIA COLI detection, as well as other cell strains. Results were achieved by combining growth kinetics of the cell population exponential phase, in 2% brilliant green lactose bile broth with bioluminescent assay, based on the reaction catalyzed by firefly luciferase. The equations applied to the description of kinetics on exponential growth phase were able to estimate the relative light units (RLU0) corresponding to initial adenosine triphosphate (ATP0) concentration. The developed equations also help to distinguish between background RLU and RLU0 corresponding to cell ATP, and to analyze the kinetics with and without lag period in order to estimate RLU0. The results demonstrated a good correlation with data obtained by standard methods for coliforms detection. The quantification of E. COLI and coliforms could be performed within a period of 6 h at 3.24 x 105 and 1.12 x 103 CFU/mL from the calculation of initial ATP concentrations at 19 and 0.067 pmol/mL, respectively. Monitoring of growth kinetic parameters along with the bioluminescent detection of microorganisms in the selective medium during shorter test time has potential for their selective and sensitive quantification. The mathematical approach may be extended to the analysis of experimental data obtained by other techniques based on the cell metabolite detection.[...] Read More.
Keywords: Bioluminescence, coliforms, Escherichia coli, exponential phase of growth, adenosine triphosphate
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文章
Marlete Brum Cleff, Iara Wendisch, Angela L. Cabana, Maria Regina Rodrigues, João Roberto Braga de Mello, Mário Carlos Araújo Meireles and Jesús Jaime Hernández-Escareño*
Abstract: The aim of this work was evaluate action of oregano (Origanum vulgare) essential oil in treatment of experimental vaginal candidiasis. A batch of 50 Wistar rats was randomly allocated into four experimental groups corresponding to treatments: T1, 1.5% oil; T2, 3% oil; T3, Nystatin and T4, control treatment (emulsion). Oil concentrations were emulsified in agar suspension at 0.8%. Vulvovaginal candidiasis was established in ovariectomized and estrus-induced rats by intravaginal inoculation of Candida albicans (106 cells-ml). Experimental rats were treated intravaginally daily for a period of 30 days and tested for clinical and hematological parameters, agent retro isolation and macroscopic alterations. Rats from T4 (Negative) treatments did exhibit major alterations exhibited in clinical parameters major alterations. Macroscopic lesions were evident in animals T1 and T4, e.g. erythema, white spots and vaginal mucosa ulcerations; two rats from T4 and one from T1 showed an enhanced uterine volume. Colony counts (UFCs) at the end of experimental period were of 3.1, 2 and 6.5 log2 for T1, T2 and T4, respectively. T3 showed the lowest UFC value of 0.5 log. Experimental results, considered as preliminary, showed a good performance for 3% O. vulgare essential oil formulation on the control of experimental vaginal candidiasis.[...] Read More.
Keywords: Vaginal candidiasis, essential oil, Origanum.
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