Fundamental Data (fundamental + data)

Distribution by Scientific Domains


Selected Abstracts


Role of the Slt2 mitogen-activated protein kinase pathway in cell wall integrity and virulence in Candida glabrata

FEMS YEAST RESEARCH, Issue 3 2010
Taiga Miyazaki
Abstract The Slt2 mitogen-activated protein kinase pathway plays a major role in maintaining fungal cell wall integrity. In this study, we investigated the effects of SLT2 deletion and overexpression on drug susceptibility and virulence in the opportunistic fungal pathogen Candida glabrata. While the ,slt2 strain showed decreased tolerance to elevated temperature and cell wall-damaging agents, the SLT2 -overexpressing strain exhibited increased tolerance to these stresses. A mutant lacking Rlm1, a transcription factor downstream of Slt2, displayed a cell wall-associated phenotype intermediate to that of the ,slt2 strain. When RLM1 was overexpressed, micafungin tolerance was increased in the wild-type strain and partial restoration of the drug tolerance was observed in the ,slt2 background. It was also demonstrated that echinocandin-class antifungals were more effective against C. glabrata under acidic conditions or when used concurrently with the chitin synthesis inhibitor nikkomycin Z. Finally, in a mouse model of disseminated candidiasis, the deletion and overexpression of C. glabrata SLT2 resulted in mild decreases and increases, respectively, in the CFUs from murine organs compared with the wild-type strain. These fundamental data will help in further understanding the mechanisms of cell wall stress response in C. glabrata and developing more effective treatments using echinocandin antifungals in clinical settings. [source]


Isotopic tracking of prehistoric pinniped foraging and distribution along the central California coast: preliminary results

INTERNATIONAL JOURNAL OF OSTEOARCHAEOLOGY, Issue 1 2002
R. K. Burton
Abstract Zooarchaeological data from Monterey Bay and the adjacent central California coast corroborate earlier observations from northern California and Oregon that Callorhinus ursinus (northern fur seal) was a much more common component in prehistoric marine mammal prey than its present pelagic distribution and foraging habits would predict. C. ursinus remains from mid-Holocene Monterey Bay occurrences are predominantly from female individuals, associated with an inshore piscifauna, and lack associated artifactual evidence for deep water exploitation. Taken together with evidence from Oregon, this suggests that mid-Holocene C. ursinus populations had different foraging, resting, and, arguably, reproductive behaviours than historically reported. Currently debated is whether the contrast between prehistoric and present patterns of pinniped species representation results from: 1) late Holocene prehistoric resource depression by aboriginal hunters, 2) depredations of the early historic fur trade, or 3) non-anthropogenic climatic or oceanographic change. The issue has thus far been addressed with presence or absence data on pinniped species and age/sex classes in dated contexts. While these are fundamental data, they cannot shed light on the nature of foraging behaviour of the species in question, a key dimension of the problem. This paper reports a pilot study utilizing stable isotope analysis aimed to elucidate prehistoric pinniped foraging patterns, specifically that of C. ursinus. Elements from six archaeological sites in Monterey and Santa Cruz counties were analysed for stable isotope compositions of carbon and nitrogen in bone collagen and compared to a latitudinally ordered modern dataset. Results for archaeological C. ursinus strongly suggest that prehistoric animals habitually foraged at lower latitudes than characterize the species today, supporting earlier claims of their year-round residency south of Alaska. Copyright © 2002 John Wiley & Sons, Ltd. [source]


Removal of fluoride using some lanthanum(III)-loaded adsorbents with different functional groups and polymer matrices

JOURNAL OF CHEMICAL TECHNOLOGY & BIOTECHNOLOGY, Issue 10 2003
Luo Fang
Abstract Although fluoride is beneficial for human beings in small quantities, it causes dental fluorosis when consumed in larger quantities over a period of time. In recent years, considerable work has been conducted for the purpose of developing new and low cost absorbents for adsorptive removal of fluoride, especially chelating resins loaded with metal ions. In the present study, several types of adsorbents with different functional groups loaded with lanthanum(III) were prepared to be used for fluoride removal from water. The optimum conditions for loading lanthanum(III) on the adsorbents and the effects of pH and initial fluoride concentration as well as shaking time and solid,liquid ratio on the removal of fluoride have been investigated. Based on these fundamental data, the removal of fluoride from actual hot spring water was also tested as a practical application by comparing the efficiency of different adsorbents for the removal of fluoride from hot spring water. The following conclusions were obtained. (1) The different chemical composition and chemical structure of the polymer matrix play the most important role in fluoride adsorption, (2) strongly acidic adsorbents are more effective on fluoride removal at neutral pH than weakly acidic adsorbents, (3) the order of fluoride removal in the neutral pH range of 4.5,8.0 by the different La(III)-loaded adsorbents employed in the present work is as follows: 200CT resin > POJRgel > IR124resin > SOJR gel , CPAgel , WK11 resin. The column experiments showed that the 200CT resin loaded with lanthanum(III) at pH 6.0 can be successfully employed for the removal of fluoride ions from actual hot spring water. Copyright © 2003 Society of Chemical Industry [source]


DYNAMIC MODELING OF RETORT PROCESSING USING NEURAL NETWORKS

JOURNAL OF FOOD PROCESSING AND PRESERVATION, Issue 2 2002
C. R. CHEN
ABSTRACT Two neural network approaches , a moving-window and hybrid neural network , which combine neural network with polynomial regression models, were used for modeling F(t) and Qv(t) dynamic functions under constant retort temperature processing. The dynamic functions involved six variables: retort temperature (116,132C), thermal diffusivity (1.5,2.3 × 10,7m2/s), can radius (40,61 mm), can height (40,61 mm), and quality kinetic parameters z (15,39C) and D (150,250 min). A computer simulation designed for process calculations of food thermal processing systems was used to provide the fundamental data for training and generalization of ANN models. Training data and testing data were constructed by both second order central composite design and orthogonal array, respectively. The optimal configurations of ANN models were obtained by varying the number of hidden layers, number of neurons in hidden layer and learning runs, and a combination of learning rules and transfer function. Results demonstrated that both neural network models well described the F(t) and Qv(t) dynamic functions, but moving-window network had better modeling performance than the hybrid ANN models. By comparison of the configuration parameters, moving-window ANN models required more neurons in the hidden layer and more learning runs for training than the hybrid ANN models. [source]


Fishing gears involved in entanglements of minke whales (Balaenoptera acutorostrata) in the East Sea of Korea

MARINE MAMMAL SCIENCE, Issue 2 2010
Kyung-Jun Song
Abstract Entanglement of marine mammals in fishing gear is a global issue. It is considered a significant threat to minke whales (Balaenoptera acutorostrata) in the East Sea of Korea. A total of 214 entanglements of minke whales in this area between 2004 and 2007 were used to investigate types and parts of fishing gears involved in entanglements. The majority of entanglements were mainly caused by three types of fishing gears: set nets, pots, and gill nets (n= 207, 96.7%). Other entanglements were associated with bottom trawls, purse seines, and trawls. A total of 65 entanglements were attributed to the main and branch lines of fishing gears. The most common body part of minke whales which attached to fishing gears was the mouth (n= 63, 30.4%). Most entanglements took place within 10 nmi from land (n= 179, 86.5%), and between 10 and 220 m of water depth. The mean length of entangled minke whales in set nets was significantly smaller than that of whales in pots and gill nets samples (P < 0.001). Also, the mean body length of minke whales that entangled in the coastal area and shallow waters was significantly shorter than that of whales in the offshore area and deep waters (P < 0.001). This information can be used as fundamental data to conserve and manage this population of minke whales in the East Sea of Korea, and also to modify fishing gear to reduce entanglements. Future studies should focus on investigating the impact of these entanglements on the population and the effectiveness of mitigation measures to reduce entanglements of minke whales in this area. [source]


Serum selenium concentration in healthy children living in Tehran

BIOFACTORS, Issue 2 2007
Reza Safaralizadeh
Abstract Introduction: Selenium is one of the essential trace elements which is more notifed in children in recent years. Reliable age-specifc reference values for selenium in children in Iran are not clear and are important for the identifcation of selenium defciency and some other researches that is the aim of this study. Methods: Serum samples of 216 healthy children were analyzed by using hydride generation and flame atomic absorption spectroscopy to measured selenium level. Results: The mean and standard deviation of serum selenium level in children 0,16 years old (mean: 39.83 months) was 72.14 ± 16.80 ,g/l. There was signifcant difference in serum selenium concentration between two sexes which was 76.78 ± 15.24 ,g/l and 69.56 ± 17.09 ,g/l in girls and boys respectively (P value = 0.002 ). There was also a positive correlation between higher selenium serum concentration and age in both sexes. Conclusion: Essential trace element's normal ranges are fundamental data which could use in many studies. Serum selenium concentration in healthy Iranian children that found in this study is very close to serum concentration of European children. Our fndings may reveal nutritional culture's similarity. [source]