A Tour of Open Universities Through Literature

Human pancreatic cells of the Capan-1 cell line differentiate in culture. During the exponential growth phase, the cells are undifferentiated, only becoming differentiated during the stationary phase. The formation of domes in this phase is related to the exchange of water and electrolytes. The present study was designed to characterize the localization and expression of alkaline phosphatases (AP) in Capan-1 cells during growth in culture. Biochemical, cytoenzymatic and immunocytochemical methods were employed combined with light and electron microscopic examination. AP essentially of the placental type were expressed progressively during the exponential growth phase, and were seen to be distributed over the surface of the Capan-1 cells. In the stationary phase, the AP became localized on the surface of microvilli. The precipitates of the enzyme reaction highlighted regular four-bodied structures. Biochemical assays showed a progressive increase in activity of this enzyme in cells during both the exponential and stationary growth phases. However, in the stationary phase between days 7 and 8, there was a fall in enzyme activity, with a corresponding increase in this activity in the culture medium. Cytological examination indicated that this fall could be accounted for by loss of AP-positive membranes by vesiculization of apical microvilli and release of microvesicles into the culture medium. Immunoblots showed that Capan-1 cells expressed two types of AP, a placental type (70 kDa) and to a lesser extent a liver type (80 kDa). Expression of the placental type was attributed to a neoplastic derepression of the coding gene, while the liver type was assumed to be a normal gene expression of human duct cells. The placental type AP might thus serve as a marker of transformation, and the liver type as a marker of differentiation.

Boron Distribution in the Developing Ovules of Clivia miniata Regel and Aesculus glabra Willd

Arsenic (As) metabolism in freshwater algae at different growth phases has rarely been documented. To address this gap, this study was conducted to assess the intra- and extracellular As metabolism, along with speciation changes, in Microcystis aeruginosa across three growth phases. The treatment involved varying concentrations of As (0, 0.4, 0.6, 0.8 and 1 mg/L, in the form of arsenate, iAsV) under three phosphorus levels (0.02 mg/L as low, 0.1 mg/L as medium, and 0.5 mg/L as high P in the form of phosphate). The findings revealed that extracellular iAsV remained the dominant As species during the lag and exponential growth phases of M. aeruginosa in the growth media, while intracellular trivalent As (iAsIII) emerged as the pronounced species during the exponential growth phase, but also exhibited a significant negative correlation with the P levels. Moreover, elevated P levels had promoted the formation of intra- and extracellular dimethylarsinic acid (DMA) and monomethylarsonic acid (MMA) in the exponential growth phase. During the stationary growth phase, intracellular iAsV was found to decrease with the increasing P levels. During the whole growth phases, P had consistently reduced algal As absorption levels. The significant promotion of algal As absorption in response to iAsV was observed only during the lag growth phase. The As bioaccumulation exhibited a correlational relationship with the algal reproduction. Both low and high P levels (0.02 and 0.5 mg/L) decreased the accumulation of As in algae cells during the exponential and stationary growth phases. The transformation and release rate of As were concomitantly influenced by P, and exhibited the same trends within the growth phase. These trends differed between the exponential and stationary growth phases, with an inhibitory effect being present during the former, while a promotional effect was observed during the latter. This study provides insight into potential As hazards in freshwater lakes with algae bloom.

Over the last decade, researchers have become increasingly interested in students' beliefs about the nature of knowledge and how these beliefs develop. Although initial psychological accounts portrayed epistemic development as a domain-independent process of cognitive maturation, recent studies have found trajectories of epistemic development to vary considerably across contexts. However, few studies have focused on cultural context. This article examines the role community values and practices play in fostering particular epistemological orientations by comparing the epistemological beliefs of 5th, 8th, and 12th graders (N = 200) from General and Religious schools in Israel regarding 2 controversies: belief in God and punishment of children. In both controversies, older participants were less likely than younger participants to consider the controversy rationally decidable. However, this shift emerged earlier in the God controversy than in the punishment controversy. In the God controversy, General pupils were less likely than Religious pupils to consider the question rationally decidable or their own beliefs infallible. But no such school differences were observed in the punishment controversy. Qualitative and quantitative analyses linked these differences to divergent discourse practices at General and Religious schools, suggesting that the relations between learning and epistemic development are more intricate than has been assumed hitherto. Epistemology is an area of philosophy concerned with questions of what knowledge is and how it is justified. Although few people give these questions such detailed and sustained attention as professional philosophers, anyone attempting to acquire, produce, or evaluate knowledge relies, at least implicitly, on some set of epistemological beliefs. Such beliefs are of obvious interest to educators. To understand how students acquire, evaluate, and justify knowledge, we need to understand what they consider knowledge to be. And to help students become discerning consumers and responsible producers of knowledge, we need to understand how people learn to exercise reflective judgment in the face of competing claims. The psychological study of epistemic development is undergoing something of a renaissance. Interest in this area can be traced back to Piaget (1970) Piaget, J. 1970. Genetic epistemology New York: Columbia University Press. [Crossref] , [Google Scholar], Dewey (1933) Dewey, J. 1933. How we think Lexington, MA: D. C. Heath and Co. [Crossref] , [Google Scholar], and beyond (e.g., Plato's Theaetetus). But only recently have psychologists begun to draw together hitherto disparate strands of empirical inquiry to chart in detail the course of epistemic development from infancy to adulthood (see, e.g., Hallett, Chandler, & Krettenauer, 2002 Hallett, D., Chandler, M. J. and Krettenauer, T. 2002. Disentangling the course of epistemic development: Parsing knowledge by epistemic content. New Ideas in Psychology, 20(2-3): 285–307. [Crossref], [Web of Science ®] , [Google Scholar]; Kuhn, Cheney, & Weinstock, 2000 Kuhn, D. 2000. Metacognitive development. Current Directions in Psychological Science, 9(5): 178–181. [Crossref], [Web of Science ®] , [Google Scholar]; Wainryb, Shaw, Langley, Cottam, & Lewis, 2004 Wainryb, C., Shaw, L. A., Langley, M., Cottam, K. and Lewis, R. 2004. Children's thinking about diversity of belief in the early school years: Judgments of relativism, tolerance, and disagreeing persons. Child Development, 75(3): 687–703. [Crossref], [PubMed], [Web of Science ®] , [Google Scholar]). Initial research in this field was conducted largely within a neo-Piagetian paradigm. Epistemic development was characterized as a progression through discrete stages or levels of epistemological understanding, each following the other in invariant sequence and constituting a comprehensive transformation of the individual's conception of knowledge (see, e.g., Chandler, 1975 Chandler, M. J. 1975. Relativism and the problem of epistemological loneliness. Human Development, 18(3): 171–180. [Crossref], [Web of Science ®] , [Google Scholar]; Kitchener & King, 1981 Kitchener, K. S. and King, P. M. 1981. Reflective judgment: Concepts of justification and their relationship to age and education. Journal of Applied Developmental Psychology, 2: 89–116. [Crossref] , [Google Scholar]; Perry, 1970 Perry, W. G. 1970. Forms of intellectual and ethical development in the college years: A scheme Troy, MO: Holt, Rinehart & Winston. [Google Scholar]). Researchers differed somewhat in their nomenclatures and in their criteria for distinguishing levels of epistemological sophistication, but they concurred broadly in positing at least two major shifts in epistemological understanding (for recent reviews, see Hofer & Pintrich, 1997 Hofer, B. K. and Pintrich, P. R. 1997. The development of epistemological theories: Beliefs about knowledge and knowing and their relation to learning. Review of Educational Research, 67(1): 88–140. [Crossref], [Web of Science ®] , [Google Scholar], 2002 Hammer, D. and Elby, A. 2002. "On the form of a personal epistemology.". In Personal epistemology: The psychology of beliefs about knowledge and knowing Edited by: Hofer, B. K. and Pintrich, P. R. 169–190. Mahwah, NJ: Lawrence Erlbaum Associates, Inc. [Google Scholar]). Initially, the individual subscribes to an objectivist conception of knowledge, in which every question is believed to have a single, correct answer that is knowable with absolute certainty. Subsequently, in a radical shift, objectivism is abandoned in favor of subjectivism, and the individual equates all knowledge claims with matters of personal taste or preference. Finally, a balance is achieved in which objective and subjective aspects of knowing are coordinated. At this "evaluativist" stage (cf. Kuhn, 1991 Kuhn, D. 1991. The skills of argument Cambridge, , England: Cambridge University Press. [Crossref] , [Google Scholar]), the individual sees knowledge as something that is constructed tentatively by evaluating the evidence for and against competing beliefs and points of view. There was some debate about the precise relations of these stages to Piaget's stages of intellectual development (see, e.g., Boyes & Chandler, 1992 Boyes, M. C. and Chandler, M. 1992. Cognitive development, epistemic doubt, and identity formation in adolescence. Journal of Youth and Adolescence, 21(3): 277–304. [Crossref], [PubMed], [Web of Science ®] , [Google Scholar]). However, they were viewed by most researchers as a kind of "post-formal operations" taking up the formal operational attainments of hypothetical thinking and perspective-taking and applying them wholesale to knowledge claims as such, in a form of meta-metacognition (see, e.g., Kitchener, 1983 Kitchener, K. S. 1983. Cognition, metacognition and epistemic cognition: A three-level model of cognitive processing. Human Development, 26: 222–232. [Crossref], [Web of Science ®] , [Google Scholar]; Kuhn, 2000 Kuhn, D. 2000. Metacognitive development. Current Directions in Psychological Science, 9(5): 178–181. [Crossref], [Web of Science ®] , [Google Scholar]; Moshman, 2003 Moshman, D. 2003. Intellectual freedom for intellectual development. Liberal Education, 89(3): 30–38. [Google Scholar]). Empirical support for this model of epistemic development came from several parallel research programs. Overall, these studies provided substantial evidence of development in the hypothesized direction (Hallett et al., 2002 Hallett, D., Chandler, M. J. and Krettenauer, T. 2002. Disentangling the course of epistemic development: Parsing knowledge by epistemic content. New Ideas in Psychology, 20(2-3): 285–307. [Crossref], [Web of Science ®] , [Google Scholar]; Hofer & Pintrich, 1997 Hofer, B. K. and Pintrich, P. R. 1997. The development of epistemological theories: Beliefs about knowledge and knowing and their relation to learning. Review of Educational Research, 67(1): 88–140. [Crossref], [Web of Science ®] , [Google Scholar]; King & Kitchener, 1994 King, P. M. and Kitchener, K. S. 1994. Developing reflective judgment San Francisco: Jossey-Bass. [Google Scholar]). However, the ages at which the key shifts in epistemological understanding were observed varied enormously from program to program. As Hallett et al. (2002) Hallett, D., Chandler, M. J. and Krettenauer, T. 2002. Disentangling the course of epistemic development: Parsing knowledge by epistemic content. New Ideas in Psychology, 20(2-3): 285–307. [Crossref], [Web of Science ®] , [Google Scholar] noted regarding the emergence of subjectivism, "one could read selectively from the literature and, with good reason, conclude that such abilities put in their appearance at either 4 or 6 or 8 or 12 or 16 or 20, or in receipt of a Ph.D." (p. 289). These vast discrepancies have led researchers to reexamine some of the assump-tions underlying their models and measures of epistemic development. In particular, researchers have begun to question the comprehensiveness of shifts in epistemological understanding and to attend more closely to the variety of contexts within which epistemic beliefs are held, employed, and articulated (cf.Elby&Ham-mer, 2001 Elby, A. and Hammer, D. 2001. On the substance of a sophisticated epistemology. Science Education, 85(5): 554–567. [Crossref], [Web of Science ®] , [Google Scholar]; Hammer&Elby, 2002 Hammer, D. and Elby, A. 2002. "On the form of a personal epistemology.". In Personal epistemology: The psychology of beliefs about knowledge and knowing Edited by: Hofer, B. K. and Pintrich, P. R. 169–190. Mahwah, NJ: Lawrence Erlbaum Associates, Inc. [Google Scholar], 2003 Hammer, D. and Elby, A. 2003. Tapping epistemological resources for learning physics. Journal of the Learning Sciences, 12(1): 53–90. [Taylor & Francis Online], [Web of Science ®] , [Google Scholar]). This attention to context has taken several forms. One line of research has sought to show that epistemic development is a some-what domain-dependent process that occurs with respect to some kinds of knowledge claim before others. For example, it has been proposed that subjectivism emerges in relation to aesthetic claims before it emerges in relation to claims about the physical world (e.g., Hallett et al., 2002 Hallett, D., Chandler, M. J. and Krettenauer, T. 2002. Disentangling the course of epistemic development: Parsing knowledge by epistemic content. New Ideas in Psychology, 20(2-3): 285–307. [Crossref], [Web of Science ®] , [Google Scholar]; Kuhn et al., 2000 Kuhn, D. 2000. Metacognitive development. Current Directions in Psychological Science, 9(5): 178–181. [Crossref], [Web of Science ®] , [Google Scholar]; Wainryb et al., 2004 Wainryb, C., Shaw, L. A., Langley, M., Cottam, K. and Lewis, R. 2004. Children's thinking about diversity of belief in the early school years: Judgments of relativism, tolerance, and disagreeing persons. Child Development, 75(3): 687–703. [Crossref], [PubMed], [Web of Science ®] , [Google Scholar]). Another line of research has sought to show that epistemological beliefs are multi di-mensional rather than unitary. For example, it has been proposed that people's beliefs about the complexity of knowledge develop more or less independently of their beliefs about its certainty (e.g., Schommer, 1990 Schommer, M. 1990. Effects of beliefs about the nature of knowledge on comprehension. Journal of Educational Psychology, 82(3): 498–504. [Crossref], [Web of Science ®] , [Google Scholar], 1993 Schommer, M. 1993. Comparisons of beliefs about the nature of knowledge and learning amongst post-secondary students. Research in Higher Education, 34(3): 355–370. [Crossref], [Web of Science ®] , [Google Scholar]). Although the accumulated empirical evidence is as yet suggestive rather than conclusive (see Elby&Hammer, 2001 Elby, A. and Hammer, D. 2001. On the substance of a sophisticated epistemology. Science Education, 85(5): 554–567. [Crossref], [Web of Science ®] , [Google Scholar]; Hallett et al., 2002 Hallett, D., Chandler, M. J. and Krettenauer, T. 2002. Disentangling the course of epistemic development: Parsing knowledge by epistemic content. New Ideas in Psychology, 20(2-3): 285–307. [Crossref], [Web of Science ®] , [Google Scholar], pp. 303–304; Kuhn et al., 2000 Kuhn, D. 2000. Metacognitive development. Current Directions in Psychological Science, 9(5): 178–181. [Crossref], [Web of Science ®] , [Google Scholar], pp. 321–322), both research programs hold out the possibility of disentangling the course of epistemic de-velopment by identifying elements of epistemological understanding that emerge at different points in the lifespan(cf.Hallett et al.,2002 Hallett, D., Chandler, M. J. and Krettenauer, T. 2002. Disentangling the course of epistemic development: Parsing knowledge by epistemic content. New Ideas in Psychology, 20(2-3): 285–307. [Crossref], [Web of Science ®] , [Google Scholar], p. 290; Wainryb et al. 2004 Wainryb, C., Shaw, L. A., Langley, M., Cottam, K. and Lewis, R. 2004. Children's thinking about diversity of belief in the early school years: Judgments of relativism, tolerance, and disagreeing persons. Child Development, 75(3): 687–703. [Crossref], [PubMed], [Web of Science ®] , [Google Scholar]). However, "domains" and "dimensions" are not the only contexts within which epistemic beliefs are situated. Just as people's epistemic beliefs may be affected by the particular content of the knowledge claims being evaluated, so too may they be affected by the particular procedures of knowledge evaluation practiced in, and sanctioned by, the communities in which they participate (cf. Hammer & Elby, 2003 Hammer, D. and Elby, A. 2003. Tapping epistemological resources for learning physics. Journal of the Learning Sciences, 12(1): 53–90. [Taylor & Francis Online], [Web of Science ®] , [Google Scholar]). Few studies have directly examined cross-cultural variation in epistemological beliefs. And those that have done so have tended to focus on comparisons between U.S. and East Asian college students (e.g., Chan & Elliott, 2002 Chan, K. and Elliott, R. G. 2002. Exploratory study of Hong Kong teacher education students' epistemological beliefs: Cultural perspectives and implications on beliefs research. Contemporary Educational Psychology, 27(3): 392–414. [Crossref], [Web of Science ®] , [Google Scholar], 2004 Chan, K. and Elliott, R. G. 2004. Epistemological beliefs across cultures: Critique and analysis of beliefs structure studies. Educational Psychology, 24(2): 123–142. [Taylor & Francis Online] , [Google Scholar]; Nisbett, Peng, Choi, & Norenzayan, 2001 Nisbett, R. E., Peng, K., Choi, I. and Norenzayan, A. 2001. Culture and systems of thought: Holistic versus analytic cognition. Psychological Review, 108(2): 291–310. [Crossref], [PubMed], [Web of Science ®] , [Google Scholar]; Zhang, 1999 Zhang, L. F. 1999. A comparison of U. S. and Chinese university students' cognitive development: The cross-cultural applicability of Perry's theory. Journal of Psychology, 133(4): 425–439. [Taylor & Francis Online], [Web of Science ®] , [Google Scholar]). Nonetheless, the findings of such studies are highly suggestive. Especially striking is Zhang's finding that Chinese students' epistemological beliefs shifted over the college years in exactly the opposite direction to those of their U.S. counterparts. Specifically, rather than moving from objectivist to subjectivist conceptions of knowledge, similar to their peers at U.S. universities, Chinese students appeared to shift from more subjectivist conceptions of knowledge to more objectivist ones. Such findings raise intriguing questions about the relations between culture and epistemic development, and about the relations between learning and epistemic development more generally. For a field of inquiry dominated by educational psychologists, remarkably little is known about these relations. As Hofer and Pintrich(1997) Hofer, B. K. and Pintrich, P. R. 1997. The development of epistemological theories: Beliefs about knowledge and knowing and their relation to learning. Review of Educational Research, 67(1): 88–140. [Crossref], [Web of Science ®] , [Google Scholar] noted, "there is little empirical evidence for precisely what fosters epistemological development or how epistemological beliefs are altered" (p. 123). Research has shown that schooling makes a difference(e.g. Bell&Linn, 2002 Bell, P. and Linn, M. C. 2002. "Beliefs about science: How does instruction contribute?". In Personal epistemology: The psychology of beliefs about knowledge and knowing Edited by: Hofer, B. K. and Pintrich, P. R. 321–346. Mahwah, NJ: Lawrence Erlbaum Associates, Inc. [Google Scholar]; King&Kitchener, 1994 King, P. M. and Kitchener, K. S. 1994. Developing reflective judgment San Francisco: Jossey-Bass. [Google Scholar]), but it has yielded little insight into how or why it makes a difference. Moreover, researchers have tended to equivocate between viewing epistemological beliefs as causes and effects of learning—as age-dependent constraints on instruction on one hand andasoutcomesof instructionon the other hand (cf. Kuhn, 1991 Kuhn, D. 1991. The skills of argument Cambridge, , England: Cambridge University Press. [Crossref] , [Google Scholar], 2003 Kuhn, D. 2003. Understanding and valuing knowing as developmental goals. Liberal Education, 89(3): 16–22. [Google Scholar]; Schommer, 1990 Schommer, M. 1990. Effects of beliefs about the nature of knowledge on comprehension. Journal of Educational Psychology, 82(3): 498–504. [Crossref], [Web of Science ®] , [Google Scholar], 1993 Schommer, M. 1993. Comparisons of beliefs about the nature of knowledge and learning amongst post-secondary students. Research in Higher Education, 34(3): 355–370. [Crossref], [Web of Science ®] , [Google Scholar]). Cross-cultural studies of age trends in epistemological belief are one way to investigate systematically the relations between age, learning, and epistemic development. If the nature and timing of age-related shifts in epistemological belief vary cross-culturally, then this is presumably because participants in different cultures learn, through participation in practices particular to their respective communities, to treat knowledge claims in different ways. To the extent that researchers can pinpoint such practices and measure their impact on individuals' epistemological beliefs, we can begin to characterize more precisely the relations between learning and epistemic development. However, in designing such studies, researchers must take great care to distinguish between reportage and editorial. "Development" is a value-laden term. Theoretical models of psychological development do more than describe a sequence; they attach values to different points along the sequence. Specifically, they define some psychological states or capacities as more mature, adequate, or sophisticated than others. When developmental studies are restricted to homogeneous cultural settings, within which there is little serious disagreement among experts about the relative adequacy of different psychological states or capacities, the risk of bias in diagnosing participants' levels of development is relatively slight. However, as the cultural heterogeneity of the sample increases, so too does the risk that the model on the basis of which participants' development is diagnosed is ethnocentrically biased against a portion of the sample. For example, beliefs that are defined as immature by the developmental model might be considered mature within one of the cultures from which the sample is drawn, or vice versa. These dangers exist to some extent in all cross-cultural studies of psychological development (see Cole & Scribner, 1974 Cole, M. and Scribner, S. 1974. Culture and thought: A psychological introduction New York: Wiley. [Google Scholar]; Greenfield & Bruner, 1966 Greenfield, P. M. and Bruner, J. S. 1966. Culture and cognitive growth. International Journal of Psychology, 1: 89–107. [Taylor & Francis Online], [Web of Science ®] , [Google Scholar]; Shweder, Mahapatra, & Miller, 1990 Shweder, R. A., Mahapatra, M. and Miller, J. G. 1990. "Culture and moral development.". In Cultural psychology: Essays on comparative human development Edited by: Stigler, J. W. 130–204. New York: Cambridge University Press. [Crossref] , [Google Scholar]). However, in cross-cultural studies of epistemic development the danger is even more clear and present. This is because there are at least four levels at which epistemological judgments can be made, and as one ascends from the first level to the fourth, the value assumptions implicit in these judgments become less visible to the naked eye but never quite disappear. At the first, most basic level, there arejudgments about the epistemic status of par-ticular claims, such as whether a given assertion (e.g., "Eating people is wrong") is known or merely believed (e.g., "John doesn't know that eating people is wrong; he merely believes that eating people is wrong"). At one level of abstraction up from such judgments, there are judgments about the epistemic status of general classes of claim, such as judgments about whether knowledge is possible about, say, matters of aesthetics or morality (e.g., "There are no such things as moral truths or moral knowledge; morality is a question of commitment—not of what is or is not the case"). At yet another level of abstraction up from such judgments, there are further judgments about the criteria by which epistemic states are distinguished one from another, such as judgments about what differentiates knowledge from belief or opin-ion (e.g., "Knowledge is justified true belief;if a belief is true but not justified, or jus-tified but not true, then it isn't known"). And beyond this third level, there is a fourth level of judgments about the relative adequacy of particular criteria for distinguishing between epistemic states, such as judgments about whether the subjectivist equation of knowledge with opinion is less adequate than the evaluativist's insistence that knowledge differs from opinion in being supported by evidence (e.g., "Subjectivism is inferior to evaluativism because it fails to account for our belief that some claims are better supported than others"). According to this analysis, authors of contemporary models of epistemic development are themselves exercising a form of epistemological judgment in articulating their models. Specifically, they are operating at the fourth level (outlined previously), expressing their own beliefs about the relative adequacy of particular epistemological orientations. This is all well and good as long as the beliefs in question are compatible with the epistemological beliefs, values, and practices of the communities to which the model is applied. However, in cross-cultural studies of epistemic development, such compatibility cannot be assumed in advance of the investigation itself. Accordingly, if one wishes to avoid ethnocentrism, one cannot conduct a cross-cultural study of epistemic development without suspending, at least temporarily, one's hierarchical assumptions about the relative adequacy of particular epistemological orientations. This is not to say that researchers are not entitled to opinions of their own about the relative adequacy of particular epistemological beliefs or that all talk of epistemic development is inherently ethnocentric. It is merely to point out that because standards of epistemological maturity may themselves vary across cultures, assumptions about the relative adequacy of particular epistemological beliefs must not be built into the design of cross-cultural studies. This study, therefore, departs from previous studies of epistemic development by dropping the assumption that some epistemological beliefs are inherently more adequate than others. By dropping this assumption, I do not affirm the contrary assumption that all epistemological beliefs are equally adequate. Rather, I adopt a form of methodological agnosticism to reduce the scope for ethnocentric bias in the study'sdesign. In the Discussion section, I return to the question of hierarchy and review the assumptions of contemporary models of epistemic development in light of my findings. This study investigates the relations between age, learning, and epistemic devel-opment by comparing the epistemological beliefs of pupil sat Religious schools and General schools in Israel about two controversies: one religious and the other nonre-ligious. Specifically, this study asks three questions. First, how do beliefs about the nature of religious claims vary with age and school? Second, to what extent are these age and school differences attributable to underlying group differences in religious commitment and general epistemological sophistication? Third, how are variations in epistemological belief across ages, schools, and controversies related to educational practices at Religious and General schools, respectively?

Variations of alkenone based paleotemperature index ( [formula omitted]) during Emiliania huxleyi cell growth, respiration (auto-metabolism) and microbial degradation

A mouse-mouse hybridoma cell line (167.4G5.3) was cultivated in a 1.5-L stirred-tank bioreactor under constant pH and dissolved oxygen concentration. The transient kinetics of cell growth, metabolism, and antibody production were followed by biochemical and flow cytometric methods. The cell-specific kinetic parameters (growth and metabolic rates) as well as cell size were constant throughout the exponential phase. Intracellular protein and RNA content followed a similar trend. Cell growth stopped when the glutamine in the medium was depleted. Glucose could not substitute for glutamine, as glucose consumption ceased after glutamine depletion. Ammonia and lactate production followed closely glutamine and glucose consumption, respectively. Alanine, glutamate, serine, and glycine were produced but other amino acids were consumed. The cells are estimated to obtain about 45% of the total energy from glycolysis, with the balance of the metabolic energy provided by oxidative phosphorylation. The antibody was produced at a constant rate in both the exponential and decline phases of growth. The intracellular antibody content of the cells remained relatively constant during the exponential phase of growth and decreased slightly afterwards.

The lipid and biochemical composition of the haptophyte Isochrysis galbana TK1 was examined. Cultures were grown at 15 °C and 30 °C, and harvested in the exponential and early stationary growth phases. Carbohydrate and protein content varied at the two culture temperatures and growth phases. The highest protein content was found at the exponential growth phase at 15 °C, and the highest carbohydrate content was found at the stationary phase at the same culture temperature. Lipid accumulated in the stationary growth phase and its content was higher at 30 °C than at 15 °C regardless of the growth phase. The neutral lipids were the major class of lipid found in all the cultures. The stationary phase culture had a higher proportion of neutral lipids than the exponential phase culture and the proportion decreased slightly when culture temperature was increased from 15 °C to 30 °C. Phospholipid levels remained constant at the two temperatures, but slightly decreased in the stationary phase. Glycolipids in the exponentially growing cells were higher than those from stationary growth phase and increased with temperature. Polyunsaturated fatty acids (PUFAs) predominated in glycolipids and phospholipids. Cells grown at 15 °C contained higher proportion of 18:3 (n–3) and 22:6 (n–3) with a corresponding decrease in 18:2 (n–6), monounsaturated and saturated fatty acids.

PurposeResearch into integrated project delivery (IPD) has attracted increased attention over the past 2 decades, and a significant number of IPD studies have been published more recently. The purpose of the study is to explore the state of IPD to reveal innovative areas of focus.Design/methodology/approachThe research presented puts forward a science mapping and bibliometrics methods to study systematic analysis of IPD scientific output published between 2006 and 2020. It uses a framework from emerging literature relating to innovation to incorporate a perspective of the process of innovation for the analysis of IPD. The adapted framework from the literature on innovation, called the Technology Innovation System (TIS), has functions that reveal novelty in the existing structures of IPD. The framework uses the analysis of scientific output from science mapping and bibliometric study techniques, using the ScienceDirect (SD) and Web of Science (WoS) databases as sources. The framework analyzes factors involved in the development and diffusion of the IPD approach and charts new knowledge development on IPD.FindingsFrom the analysis, future implementation of IPD will converge on cases of collaboration, as a systemic feature, among participating stakeholder teams. A significant and robust effect resulted from collaboration and integration as major mechanisms influence opportunities, problems and solutions within construction firms using IPD, marking a future trend. Reports further substantiate the importance and focus on collaboration and integration between IPD practitioners. With the same dynamic and gradual prominence, building information modeling (BIM) and new technology applications demonstrated the importance of the development and diffusion of IPD in the form of, for example, digital government initiatives. It is expected that the trend for IDS and resource mobilization functions will continue to grow – clear evidence of the benefits of the IPD approach in the construction sector. New evidence for gaining cognitive and normative legitimacy emerged. The expansion of new avenues for further legitimation is expected to enable growth.Research limitations/implicationsBeyond the innovative approach of viewing IPD from the emerging innovation framework, the research presented fully contributes to IPD literature, providing a comprehensive state-of-the-art status and a quantitative analysis of IPD scientific output, thereby illuminating promising work areas for future research into IPD. The main limitation is related to the dynamic process of indexing of IPD literature in the WoS and SD – although many new research publications are added in the discipline, only a part of them have been indexed in the WoS and SD core database.Practical implicationsThe study revealed key evolving trends within the field, including instructive findings and implications concerning possible deficiencies. Based on factors from network visualizations and quantitative evaluation from major influential articles, journals and authors, future critical IPD implementation focus will be on BIM and sustainability concepts – centerpiece concepts for the evolving line of IPD growth and development in the architecture, engineering and construction industry.Social implicationsThis study fills the gap created in a shortage of studies mapping out the most critical contributions in journals, authors and research perspectives related to IPD. It presents a framework that can be used as an objective procedure to evaluate the topic. It is expected that the study will serve as a cornerstone for researchers in this field, as it provides a bibliometric analysis and presents trends using an analytical framework of innovation.Originality/valueThe research presented is a keystone in the foundation of the literature review on this topic. The research draws on an existing framework for innovation – the TIS, developed from innovation studies using a robust theoretical framework to enable further analysis of IPD. This approach is one of a kind, using the results of scientometric analysis to study the scientific landscape and knowledge output of IPD in the AEC community. Science-mapping bibliometric analysis was conducted to shed light on IPD trends and explain factors that back or support the development and diffusion of IPD, including shaping and enabling evolution and growth. The framework helps to shed light on the interaction of socio-technical structures (i.e. stakeholders, technologies and rules) embedded in the industry, which helped create, direct and advance IPD in the project delivery system.

AME Aquatic Microbial Ecology Contact the journal Facebook Twitter RSS Mailing List Subscribe to our mailing list via Mailchimp HomeLatest VolumeAbout the JournalEditorsSpecials AME 35:57-64 (2004) - doi:10.3354/ame035057 Production of superoxide anion and hydrogen peroxide associated with cell growth of Chattonella antiqua Daekyung Kim1,2, Masataka Watanabe1,*, Yoko Nakayasu1, Kunio Kohata3 1Water and Soil Environment Division, National Institute for Environmental Studies, Onogawa, Tsukuba, Ibaraki 305-8506, Japan 2Japan Society for the Promotion of Science (JSPS), Kojimachi Office, Yamato Building, 5-3-1 Kojimachi, Chiyoda-ku, Tokyo 102-8471, Japan 3Watershed Environmental Management Group, National Institute for Environmental Studies, Onogawa, Tsukuba, Ibaraki 305-8506, Japan *Corresponding author. Email: masawata@nies.go.jp ABSTRACT: The production of reactive oxygen species (ROS) by the red tide flagellate Chattonella antiqua (Raphidophyceae) was investigated. Flagellates were grown in an NIES (National Institute for Environmental Studies) culture tank containing 1 m3 of f/2 medium under synchronized light conditions (12:12 h, L:D period). Raphidophycean flagellates are known to form ROS, such as the superoxide anion (O2-) and hydrogen peroxide (H2O2) under normal growth conditions. We confirmed that C. antiqua generated O2- depending on the cell growth phase by chemiluminescence responses. O2- production had a maximum value during the exponential growth phase and subsequently decreased in the stationary phase. However, the maximum production of H2O2 occurred in the early stationary growth phase. These results showed that O2- and H2O2 generation pathways were different from each other in C. antiqua. The highest activity rates of both O2- and H2O2 per carbon content (μg carbon-1) were observed during the exponential growth phase, but the pattern of ROS generation was significantly different between O2- and H2O2 during cell growth. Two sets of intensive observations (at 3 h intervals) were conducted for diel phasing of the cell cycle in the exponential and stationary growth phases. In the exponential growth phase, O2- and H2O2 production rates increased during the light period and decreased during the dark period, in spite of the increase in cell density due to cell division, indicating that the rates were affected by photosynthesis. The patterns of ROS production during the stationary growth phase were similar to those in the exponential phase, although the growth rate had less effect during the stationary than in the exponential phase. KEY WORDS: Cell cycles · Chattonella antiqua · Hydrogen peroxide · NIES culture tank · Reactive oxygen species · Red tide · Superoxide anion Full article in pdf format PreviousNextExport citation RSS - Facebook - Tweet - linkedIn Cited by Published in AME Vol. 35, No. 1. Online publication date: April 02, 2004 Print ISSN: 0948-3055; Online ISSN: 1616-1564 Copyright © 2004 Inter-Research.

Diatoms are capable of accumulating substantial amounts of triacylglycerides in their cells, which differ in the composition of fatty acids depending on the conditions of cultivation, making them attractive subjects in biotechnology. In the present study, we characterized the structural features of lipid bodies in the diatom Entomoneis cf. paludosa (W. Smith) Reimer strain 8.0727-B and revealed the peculiarities of fatty acid composition in cultures during the stationary and exponential growth phases. Laser scanning confocal microscopy revealed an increased number of lipid bodies in the cytoplasm during the stationary phase of culture growth. Electron microscopy of ultrathin sections showed that an extreme increase in the number and size of plastoglobules in the cells occurs in the stationary phase of culture growth. The gas chromatography with mass spectrometric detection method revealed differences in the fatty acid composition depending on the growth phase. The studied strain can be recommended as a source of hexadecanoic and octadecanoic fatty acids from the culture during the stationary growth phase, as well as eicosapentaenoic fatty acid from the culture during the exponential growth phase.

Changes in bacterial cells induced by high pressure at subzero temperature

Objective Evaluate the efficiency of scientific research output of the 54 departments in a hospital, to put forward improvement suggestions based on the evaluation results. Methods Select appropriate indicators of scientific input and output, use the Data Envelopment Analysis method to evaluate and analyze the efficiency. Results According to the analysis of DEA, calculate the values of overall efficiency, technical efficiency, scale efficiency and scale income. Then compare and analyze the relative efficiency of different units scientific output, to identify the relatively superior department among the various categories. Conclusions According to the evaluation results, to find out the input surplus and insufficient output of each decision units. Then we will put forward suggestions on hospital resource allocation to optimize the scientific input and output, to improve the competitiveness of the hospital, and to activate the potential of each department’s scientific research. Key words: Data envelopment analysis; Hospital department; Scientific output; Efficiency evaluation,

Enhancement of growth rate and β-galactosidase activity, and variation in organic acid profile of Bifidobacterium animalis subsp. lactis Bb 12

The increase in open and distance education and the rise of open university movement in the field of higher education have resulted in the establishment of open mega universities in different parts of the world with populations of more than 100,000 students each. Despite the benefits of access and low costs, the main criticism of this type of institution has been about quality assurance. The aim of this paper is 1) to compare and contrast three open mega universities namely Anadolu University in Turkey, Indira Gandhi National Open University in India, and Open University in Britain, in terms of their missions, visions, mottos, learning environments, entrance requirements, and quality assurance policies as they appeared on their official websites; and 2) to highlight their alignment with the open university movement. This qualitative study employs a comparative case study approach, and analyses data with the constant comparative method. Major findings suggested that these universities seemed to establish their access strategies and lower their costs through massification. They appeared to be concerned about quality assurance policies on their websites mainly to attract student masses around the world. The question we raise is the extent to which the balance between quality and quantity is reached in actual educational settings.

Background: Physiotherapy research supports the advancement of evidence-based practice and the development of a highly skilled workforce. This study aims to visualize the highly cited scientific output of Indian physiotherapists from 1999 to 2018. Methods: A descriptive study design was adopted to visualize the highly cited scientific output of Indian physiotherapists using the Web of Science (WoS) database from 1999 to 2018. A search was carried out using the following keywords "((TS=(physiotherapy) OR TS=("physical rehabilitation") OR TS=("physical therapy")) AND AD=(India))Indexes=SCI-EXPANDED, SSCI, A&HCI, CPCI-S, CPCI-SSH, ESCI, CCR-EXPANDED, IC Timespan=1999-2018". Data collected were analyzed using Incites from WoS and VOSviewer software. Results: A total of 488 articles were published between 1999 and 2018, with a peak of 103 in 2016 with 2419 citations. A decline in publication count was observed after 2016. The journal International Journal of Physiotherapy published the highest number of articles (n=35). Manipal University (n=36) was found to be the most active institution for physiotherapy research in India, as determined by publishing the most articles. Indian physiotherapists published the highest number of research articles in collaboration with US authors (n=24). Conclusion: There is an increasing trend in the scientific output of Indian physiotherapists over the past two decades; however, a decline is observed after 2016. It is recommended that research collaborations across the globe are increased and scientific output should be improved, leading to a higher number of citations. Future research should explore factors influencing the scientific production of Indian physiotherapists and devise appropriate strategies to attain further improvement.