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Selected AbstractsBacterial energetics, stoichiometry, and kinetic modeling of 2,4-Dinitrotoluene biodegradation in a batch respirometerENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 12 2004Chunlong Zhang Abstract A stoichiometric equation and kinetic model were developed and validated using experimental data from batch respirometer studies on the biodegradation of 2,4-dinitrotoluene (DNT). The stoichiometric equation integrates bacterial energetics and is revised from that in a previous study by including the mass balance of phosphorus (P) in the biomass. Stoichiometric results on O2 consumption, CO2 evolution, and nitrite evolution are in good agreement with respirometer data. However, the optimal P requirement is significantly higher than the stoichiometrically derived P, implying potentially limited bioavailability of P and the need for buffering capacity in the media to mitigate the adverse pH effect for optimal growth of DNT-degrading bacteria. An array of models was evaluated to fit the O2/CO2 data acquired experimentally and the DNT depletion data calculated from derived stoichiometric coefficients and cell yield. The deterministic, integrated Monod model provides the goodness of fit to the test data on DNT depletion, and the Monod model parameters (Ks, X0, ,max, and Y) were estimated by nonlinear regression. Further analyses with an equilibrium model (MINTEQ) indicate the interrelated nature of medium chemical compositions in controlling the rate and extent of DNT biodegradation. Results from the present batch respirometer study help to unravel some key factors in controlling DNT biodegradation in complex remediation systems, in particular the interactions between acidogenic DNT bacteria and various parameters, including pH and P, the latter of which could serve as a nutrient, a buffer, and a controlling factor on the bioavailable fractions of minerals (Ca, Fe, Zn, and Mo) in the medium. [source] A Native-Like Ability to CircumlocuteMODERN LANGUAGE JOURNAL, Issue 2 2000Sarah Jourdain The ability to circumlocute successfully is of utmost importance in compensating for gaps in lexical knowledge. Although all studies indicate that one's ability to circumlocute increases with increasing proficiency, it is interesting that little attention has been paid to those learners who have the greatest ability to circumlocute, native-like speakers. This study addresses the norms of native and native-like circumlocution. It expands the discussion of strategies involved in this skill to include the means by which speakers frame their message and thereby set the linguistic context for their listeners. Participants in this study, both native and native-like speakers, were found to employ similar strategies while circumlocuting, including the use of synonyms, analogies, and descriptions. These participants also consistently framed their speech to facilitate listener comprehension, and they frequently included in their discourse some reference to their status as a nonexpert in the field. Similarities in native and native-like circumlocution found in this study help to provide some empirical validation to the notion of "native-like." [source] Proteome, salicylic acid, and jasmonic acid changes in cucumber plants inoculated with Trichoderma asperellum strain T34PROTEINS: STRUCTURE, FUNCTION AND BIOINFORMATICS, Issue 21 2007Guillem Segarra Abstract Trichoderma spp. is one of the most commonly used biological control agents against plant pathogens. This fungus produces changes in plant metabolism, thus increasing growth and enhancing resistance to biotic and abiotic stresses. However, its modes of action remain to be defined. In the first hours of interaction between cucumber plant roots and Trichoderma asperellum strain T34, salicylic and jasmonic acid levels and typical antipathogenic peroxidase activity increase in the cotyledons to different degrees depending on the applied concentration of the fungi. The use of 2-DE protein profiling and MS analysis allowed us to identify 28 proteins whose expression was affected in cotyledons after cucumber root colonization by Trichoderma applied at high concentrations: 17 were found to be up-regulated while 11 were down-regulated. Proteins involved in ROS scavenging, stress response, isoprenoid and ethylene biosynthesis, and in photosynthesis, photorespiration, and carbohydrate metabolism were differentially regulated by Trichoderma. The proteome changes found in this study help to give an understanding of how Trichoderma -treated plants become more resistant to pathogen attacks through the changes in expression of a set of defence-oriented proteins which can directly protect the plant or switch the metabolism to a defensive, nonassimilatory state. [source] AMPA and metabotropic glutamate receptors cooperatively generate inspiratory-like depolarization in mouse respiratory neurons in vitroEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 12 2008Ryland W. Pace Abstract Excitatory transmission mediated by AMPA receptors is critical for respiratory rhythm generation. However, the role of AMPA receptors has not been fully explored. Here we tested the functional role of AMPA receptors in inspiratory neurons of the neonatal mouse preBötzinger complex (preBötC) using an in vitro slice model that retains active respiratory function. Immediately before and during inspiration, preBötC neurons displayed envelopes of depolarization, dubbed inspiratory drive potentials, that required AMPA receptors but largely depended on the Ca2+ -activated non-specific cation current (ICAN). We showed that AMPA receptor-mediated depolarization opened voltage-gated Ca2+ channels to directly evoke ICAN. Inositol 1,4,5-trisphosphate receptor-mediated intracellular Ca2+ release also evoked ICAN. Inositol 1,4,5-trisphosphate receptors acted downstream of group I metabotropic glutamate receptor activity but, here too, AMPA receptor-mediated Ca2+ influx was essential to trigger the metabotropic glutamate receptor contribution to inspiratory drive potential generation. This study helps to elucidate the role of excitatory transmission in respiratory rhythm generation in vitro. AMPA receptors in preBötC neurons initiate convergent signaling pathways that evoke post-synaptic ICAN, which underlies inspiratory drive potentials. The coupling of AMPA receptors with ICAN suggests that latent burst-generating intrinsic conductances are recruited by excitatory synaptic interactions among preBötC neurons in the context of respiratory network activity in vitro, exemplifying a rhythmogenic mechanism based on emergent properties of the network. [source] Nuclear power plant communications in normative and actual practice: A field study of control room operators' communicationsHUMAN FACTORS AND ERGONOMICS IN MANUFACTURING & SERVICE INDUSTRIES, Issue 1 2007Paulo V.R. Carvalho The safety and availability of sociotechnical critical systems still relies on human operators, both through human reliability and human ability to handle adequately unexpected events. In this article, the authors focus on ergonomic field studies of nuclear power plant control room operator activities, and more specifically on the analysis of communications within control room crews. They show how operators use vague and porous verbal exchanges to produce continuous, redundant, and diverse interactions to successfully construct and maintain individual and mutual awareness, which is paramount to achieve system stability and safety. Such continuous interactions enable the operators to prevent, detect, and reverse system errors or flaws by anticipation or regulation. This study helps in providing cues for the design of more workable systems for human cooperation in nuclear power plant operation. © 2007 Wiley Periodicals, Inc. Hum Factors Man 17: 43,78, 2007. [source] Aggression towards health care staff in a UK general hospital: variation among professions and departmentsJOURNAL OF CLINICAL NURSING, Issue 1 2004Sue Winstanley BSc Background., Aggression towards health care staff is an increasing problem and although many studies have examined psychiatric settings, few have considered general hospitals and in particular, variation among professions and locations. In addition, studies often fail to include all forms of aggression such as threatening behaviour and verbal aggression. Methods., This study extends existing research by evaluating physical assault, threatening behaviour and verbal aggression from patients/visitors towards general hospital staff in the context of different professions and departments. Results and conclusions., The survey of staff showed that aggression is widespread. Within the preceding year, 27% of the respondents were assaulted, 23% experienced threatening behaviour from patients and 15.5% experienced threatening behaviour from visitors. Over 68% reported verbal aggression, 25.7% experiencing it more regularly than monthly. By departments, over 42% of the medical department staff, 36% of the surgical staff and over 30% of the Accident and Emergency staff were assaulted. By profession, staff nurses and enrolled nurses reported the most assaults (43.4%) and doctors, the fewest (13.8%). Other nursing grades and health care professions all reported levels of physical assault in excess of 20%. Correspondingly high levels of threatening behaviour and verbal aggression were also reported although the patterns of victimization differed according to the various professions and departments. Independently, significant levels of assault, threatening behaviour and verbal aggression were reported. When aggregated they demonstrate the higher levels of victimization that general hospital staff experienced on a regular basis. Relevance to clinical practice., Institutional averages actually obscure the much higher levels of aggression experienced by the particular professions in particular departments. This study helps to localize the problem and identify those at most risk, but more research is needed into the aetiology of the aggression and of vulnerability factors associated with victimization. [source] Effects of temperature on disease progression and swimming stamina in Ichthyophonus -infected rainbow trout, Oncorhynchus mykiss (Walbaum)JOURNAL OF FISH DISEASES, Issue 10 2009R Kocan Abstract Rainbow trout, Oncorhynchus mykiss, were infected with Ichthyophonus sp. and held at 10 °C, 15 °C and 20 °C for 28 days to monitor mortality and disease progression. Infected fish demonstrated more rapid onset of disease, higher parasite load, more severe host tissue reaction and reduced mean-day-to-death at higher temperature. In a second experiment, Ichthyophonus -infected fish were reared at 15 °C for 16 weeks then subjected to forced swimming at 10 °C, 15 °C and 20 °C. Stamina improved significantly with increased temperature in uninfected fish; however, this was not observed for infected fish. The difference in performance between infected and uninfected fish became significant at 15 °C (P = 0.02) and highly significant at 20 °C (P = 0.005). These results have implications for changes in the ecology of fish diseases in the face of global warming and demonstrate the effects of higher temperature on the progression and severity of ichthyophoniasis as well as on swimming stamina, a critical fitness trait of salmonids. This study helps explain field observations showing the recent emergence of clinical ichthyophoniasis in Yukon River Chinook salmon later in their spawning migration when water temperatures were high, as well as the apparent failure of a substantial percentage of infected fish to successfully reach their natal spawning areas. [source] Sense of Place in Hanoi's Shop-House: The Influences of Local Belief on Interior ArchitectureJOURNAL OF INTERIOR DESIGN, Issue 1 2010Dinh Quoc Phuong Ph.D. The aim of this article is to seek another way of understanding the interdisciplinary, albeit loosely defined notion of "sense of place" and its manifestation in interior characteristics and design of domestic space in Hanoi. This includes an analysis of one aspect of place identities through material culture, such as those that are reflected in the local system of belief and building rite known as phong thuy,the Vietnamese version of Chinese feng-shui. With a case study research approach,describing and analyzing different types of data collected from a selected case study,this article examines sense of place and phong thuy application in (re)designing a shop-house, the most popular building type in Asian high-density cities like Hanoi. This study helps to explain how sense of place is understood by owner-builders, and how such a view is important to consider when attempting to design and make the home interior a better living place for residents in Hanoi and elsewhere. [source] Aminoglycoside-mediated partial suppression of MECP2 nonsense mutations responsible for Rett syndrome in vitroJOURNAL OF NEUROSCIENCE RESEARCH, Issue 11 2010Andreea C. Popescu Abstract Rett syndrome is a pediatric neurological condition that affects primarily girls. Approximately 30% of Rett syndrome cases arise from point mutations that introduce a premature stop codon into the MECP2 gene. Several studies have now shown that certain aminoglycosides can facilitate read-through of some types of nonsense mutations in a context-dependent manner and allow the generation of a full-length protein. It remains mostly unclear whether different nonsense mutations of MECP2 will be responsive to aminoglycoside treatment. In this study, we tested whether the common premature terminating mutations of MECP2 seen in Rett syndrome cases can be partially suppressed by aminoglycoside administration. Our results show that aminoglycosides allow different mutant forms of MECP2 to be overcome in transiently transfected HEK293 cells, but with differing levels of efficiency. In addition, we also show that aminoglycosides increased the prevalence of full-length MeCP2 protein in a dose-dependent manner in a lymphocyte cell line derived from a Rett syndrome girl with the R255X mutation. This study helps to establish the "proof of principle" that some nonsense mutations causing Rett syndrome can be at least partially suppressed by drug treatment. © 2010 Wiley-Liss, Inc. [source] Comparing Innovation Capability of Small and Medium-Sized Enterprises: Examining the Effects of Organizational Culture and EmpowermentJOURNAL OF SMALL BUSINESS MANAGEMENT, Issue 3 2010Nigar Demircan Çakar This study analyzes the impact of organizational culture and empowerment on innovation capability, and examines the peculiarities of these effects. The study's hypotheses are tested by applying both individual and firm-level analyses to survey data collected from 743 employees from 93 small and medium-sized firms located in Turkey. For medium-sized enterprises on both the individual and firm level of analysis, results suggest that collectivism and uncertainty avoidance are positively associated with empowerment, whereas power distance is negatively related to empowerment. Assertiveness focus has no relations with empowerment and innovation capability, yet among cultural dimensions, only uncertainty avoidance is related to innovation capability. For small-sized enterprises, findings suggest that both power distance and uncertainty avoidance are linked to both empowerment and innovation capability on the individual level, whereas two new paths between collectivism and innovation capability and between assertiveness focus and empowerment are found on the firm level. Also, empowerment is found to be positively related to innovation capability for both small and medium-sized enterprises (SMEs) on both the individual and firm level. In terms of managerial practice, our study helps clarify the key role played by cultural dimensions in the process of shaping an empowering and innovative work environment. Findings also reveal that managers should focus on participative managerial practices (e.g., empowerment) to promote innovation capability of SMEs. [source] Is there a problem with mathematical psychology in the eighteenth century?JOURNAL OF THE HISTORY OF THE BEHAVIORAL SCIENCES, Issue 4 2006A fresh look at Kant's old argument Common opinion ascribes to Immanuel Kant the view that psychology cannot become a science properly so called, because it cannot be mathematized. It is equally common to claim that this reflects the state of the art of his times; that the quantification of the mind was not achieved during the eighteenth century, while it was so during the nineteenth century; or that Kant's so-called "impossibility claim" was refuted by nineteenth-century developments, which in turn opened one path for psychology to become properly scientific. These opinions are often connected, but they are misguided nevertheless. In Part I, I show how the issue of a quantification of the mind was discussed before Kant, and I analyze the philosophical considerations both of pessimistic and optimistic authors. This debate reveals a certain progress, although it remains ultimately undecided. In Part II, I present actual examples of measuring the mind in the eighteenth century and analyze their presuppositions. Although these examples are limited in certain ways, the common view that there was no such measurement is wrong. In Part III, I show how Kant's notorious " impossibility claim" has to be viewed against its historical background. He not only accepts actual examples of a quantitative treatment of the mind, but also takes steps toward an explanation of their possibility. Thus, he does not advance the claim that the mind as such cannot be mathematized. His claim is directed against certain philosophical assumptions about the mind, assumptions shared by a then-dominating, strongly introspectionist conception of psychology. This conception did and could not provide an explanation of the possibility of quantifying the mind. In concluding, I reflect on how this case study helps to improve the dispute over when and why psychology became a science. © 2006 Wiley Periodicals, Inc. [source] NEW ZEALAND CREDIT UNION MERGERSANNALS OF PUBLIC AND COOPERATIVE ECONOMICS, Issue 3 2010Lynn Mcalevey ABSTRACT,:,Research into the benefits of mergers in small financial institutions, in particular credit unions, is sparse. This study helps to fill this gap by analyzing recent intense merger activity in New Zealand credit unions. The major driver for these mergers was not the usual reason of attempting to increase efficiency for competitive purposes but rather enforced government action. Data envelopment analysis is used to explore changes in efficiency in merged credit unions between 1996 and 2001. Those credit unions not involved in merger activity are used as a control group. Overall, credit unions have become more efficient over the period, notably in those that undertook mergers. The Malmquist index indicates significant technological progress over the period but a slight regression in terms of efficiency. [source] Behavioral Response of Resident Jamaican Birds to Dry Season Food Supplementation,BIOTROPICA, Issue 1 2006David R. Brown ABSTRACT We used plot-level manipulations and analyses to test the effects of food availability on the behavior and condition of resident dry-forest birds in Jamaica. Two control plots were monitored in each of 2 yr. Food was supplemented on five plots over 2 yr with piles of cut oranges distributed around plots, which served as a direct source of carbohydrates and water, and an indirect source of ground arthropods due to increased above-ground activity. We reduced ants on five plots over 2 yr; however, we found no difference in total ground arthropod biomass between control and reduction treatments, so we pooled these plots for analysis. We selected nine focal resident bird species for study of relative abundance, body condition, and breeding condition. Birds were sampled prior to, and 5 to 6 weeks after the initiation of treatments. Seven of nine species had higher relative abundance following food supplementation. Three species were recaptured more frequently in supplementation plots than in control plots. These abundance and persistence responses did not cause any changes in body condition. In one species, Bananaquit (Coereba flaveola), food supplementation resulted in higher concentrations of individuals in breeding condition. These results demonstrate a functional response to dry-season food availability and suggest a limiting mechanism. This study helps explain mechanisms by which bird populations respond to resource availability, and is the first successful plot-level food supplementation experiment for tropical forest birds. [source] | ||||||||||||||||