Long-term Growth (long-term + growth)

Distribution by Scientific Domains

Terms modified by Long-term Growth

  • long-term growth rate

  • Selected Abstracts


    The influence of first-feeding diet on the Atlantic cod Gadus morhua phenotype: survival, development and long-term consequences for growth

    JOURNAL OF FISH BIOLOGY, Issue 1 2010
    R. M. Koedijk
    Atlantic cod Gadus morhua larvae reached four-fold (at low larval density) to 11 fold higher body mass (high larval density) at 50 days post hatch (dph) when fed zooplankton rather than enriched rotifers. A short period (22,36 dph) of dietary change affected larval growth positively if changed from enriched rotifers to natural zooplankton and negatively if prey type changed vice versa. Overall survival did not differ between the two larval groups at low larval density, but at high density the rotifer group had a higher overall survival (10·8% v. 8·9%). Long-term growth was affected significantly by larval diet in favour of the zooplankton diet; juveniles reached a 23% higher mass in a 12 week growth period. No difference in growth performance was found between juveniles fed natural zooplankton during the larval period for 36, 22 or 14 days, but all these juveniles performed significantly better compared with the rotifer-fed group. These findings suggest that optimal diet during a short period in the larval period can result in improved growth in both the larval and juvenile period. Improved rotifer quality may, therefore, hold a large potential for growth improvement in this species. [source]


    Long-term growth of soybean at elevated [CO2] does not cause acclimation of stomatal conductance under fully open-air conditions

    PLANT CELL & ENVIRONMENT, Issue 9 2006
    ANDREW D. B. LEAKEY
    ABSTRACT Accurately predicting plant function and global biogeochemical cycles later in this century will be complicated if stomatal conductance (gs) acclimates to growth at elevated [CO2], in the sense of a long-term alteration of the response of gs to [CO2], humidity (h) and/or photosynthetic rate (A). If so, photosynthetic and stomatal models will require parameterization at each growth [CO2] of interest. Photosynthetic acclimation to long-term growth at elevated [CO2] occurs frequently. Acclimation of gs has rarely been examined, even though stomatal density commonly changes with growth [CO2]. Soybean was grown under field conditions at ambient [CO2] (378 µmol mol,1) and elevated [CO2] (552 µmol mol,1) using free-air [CO2] enrichment (FACE). This study tested for stomatal acclimation by parameterizing and validating the widely used Ball et al. model (1987, Progress in Photosynthesis Research, vol IV, 221,224) with measurements of leaf gas exchange. The dependence of gs on A, h and [CO2] at the leaf surface was unaltered by long-term growth at elevated [CO2]. This suggests that the commonly observed decrease in gs under elevated [CO2] is due entirely to the direct instantaneous effect of [CO2] on gs and that there is no longer-term acclimation of gs independent of photosynthetic acclimation. The model accurately predicted gs for soybean growing under ambient and elevated [CO2] in the field. Model parameters under ambient and elevated [CO2] were indistinguishable, demonstrating that stomatal function under ambient and elevated [CO2] could be modelled without the need for parameterization at each growth [CO2]. [source]


    Sensitivity analysis of transient population dynamics

    ECOLOGY LETTERS, Issue 1 2007
    Hal Caswell
    Abstract Short-term, transient population dynamics can differ in important ways from long-term asymptotic dynamics. Just as perturbation analysis (sensitivity and elasticity) of the asymptotic growth rate reveals the effects of the vital rates on long-term growth, the perturbation analysis of transient dynamics can reveal the determinants of short-term patterns. In this article, I present a completely new approach to transient sensitivity and elasticity analysis, using methods from matrix calculus. Unlike previous methods, this approach applies not only to linear time-invariant models but also to time-varying, subsidized, stochastic, nonlinear and spatial models. It is computationally simple, and does not require calculation of eigenvalues or eigenvectors. The method is presented along with applications to plant and animal populations. [source]


    APPLYING NORTH'S LAWS OF MOTION TO THE EDGE OF THE WEST

    ECONOMIC AFFAIRS, Issue 2 2009
    Saad Azmat
    This paper uses Douglass North's theories of institutional economics to explain progress in Muslim Spain. It argues that it was efficient economic institutions in the guise of a free-market economy where the property rights of different strata of society were well protected, which ensured lasting prosperity. This paper postulates that while a population explosion could have been responsible for the initial growth in Spain, it was an efficient formal,informal institutional matrix that ensured a high level of long-term growth. [source]


    PARENTAL EFFECTS AND GENDER SPECIALIZATION IN A TROPICAL HETEROSTYLOUS SHRUB

    EVOLUTION, Issue 3 2000
    Germá;n Avila-Sakar
    Abstract., Male sterility in hermaphroditic species may represent the first step in the evolution toward dioecy. However, gender specialization will not proceed unless the male-sterile individuals compensate for fitness lost through the male function with an increase in fitness through the female function. In the distylous shrub Erythroxylum havanense, thrum plants are partially male-sterile. Using data collected throughout eight years, we investigated whether thrum individuals have an increased performance as female parents, thereby compensating for their loss of male fitness. We found that thrum plants outperformed pins in the probabilities of seed maturation and germination and long-term growth of the seedlings. In turn, pollen from pin plants achieved greater pollen tube growth rates. Our results suggest that the superior performance of the progeny of thrum maternal plants is a consequence of better seed provisioning via effects of the maternal environment, cytotype or nuclear genes. Overall, our results suggest that E. havanense is evolving toward a dioecious state through a gynodioecious intermediate stage. This evolutionary pathway is characterized by an unusual pattern of gender dimorphism with thrums becoming females and pins becoming males. We propose that this pattern may be better explained by the interaction between male-sterility cytoplasmic genes and the heterostyly supergene. [source]


    Trade-offs in low-light CO2 exchange: a component of variation in shade tolerance among cold temperate tree seedlings

    FUNCTIONAL ECOLOGY, Issue 2 2000
    M. B. Walters
    Abstract 1.,Does enhanced whole-plant CO2 exchange in moderately low to high light occur at the cost of greater CO2 loss rates at very-low light levels? We examined this question for first-year seedlings of intolerant Populus tremuloides and Betula papyrifera, intermediate Betula alleghaniensis, and tolerant Ostrya virginiana and Acer saccharum grown in moderately low (7·3% of open-sky) and low (2·8%) light. We predicted that, compared with shade-tolerant species, intolerant species would have characteristics leading to greater whole-plant CO2 exchange rates in moderately low to high light levels, and to higher CO2 loss rates at very-low light levels. 2.,Compared with shade-tolerant A. saccharum, less-tolerant species grown in both light treatments had greater mass-based photosynthetic rates, leaf, stem and root respiration rates, leaf mass:plant mass ratios and leaf area:leaf mass ratios, and similar whole-plant light compensation points and leaf-based quantum yields. 3.,Whole-plant CO2 exchange responses to light (0·3,600 µmol quanta m,2 s,1) indicated that intolerant species had more positive CO2 exchange rates at all but very-low light (< 15 µmol quanta m,2 s,1). In contrast, although tolerant A. saccharum had a net CO2 exchange disadvantage at light > 15 µmol quanta m,2 s,1, its lower respiration resulted in lower CO2 losses than other species at light < 15 µmol quanta m,2 s,1. 4.,Growth scaled closely with whole-plant CO2 exchange characteristics and especially with integrated whole-plant photosynthesis (i.e. leaf mass ratio × in situ leaf photosynthesis). In contrast, growth scaled poorly with leaf-level quantum yield, light compensation point, and light-saturated photosynthetic rate. 5.,Collectively these patterns indicated that: (a) no species was able to both minimize CO2 loss at very-low light (i.e. < 15 µmol quanta m,2 s,1) and maximize CO2 gain at higher light (i.e. > 15 µmol quanta m,2 s,1), because whole-plant respiration rates were positively associated with whole-plant photosynthesis at higher light; (b) shade-intolerant species possess traits that maximize whole-plant CO2 exchange (and thus growth) in moderately low to high light levels, but these traits may lead to long-term growth and survival disadvantages in very-low light (< 2·8%) owing, in part, to high respiration. In contrast, shade-tolerant species may minimize CO2 losses in very-low light at the expense of maximizing CO2 gain potential at higher light levels, but to the possible benefit of long-term survival in low light. [source]


    Geochemistry of peridotite xenoliths in alkali basalts from Jeju Island, Korea

    ISLAND ARC, Issue 4 2002
    SEONG HEE CHOI
    Abstract Ultramafic xenoliths in alkali basalts from Jeju Island, Korea, are mostly spinel lherzolites with subordinate amounts of spinel harzburgites and pyroxenites. The compositions of major oxides and compatible to moderately incompatible elements of the Jeju peridotite xenoliths suggest that they are residues after various extents of melting. The estimated degrees of partial melting from compositionally homogeneous and unfractionated mantle to form the residual xenoliths reach 30%. However, their complex patterns of chondrite-normalized rare earth element, from light rare earth element (LREE)-depleted through spoon-shaped to LREE-enriched, reflect an additional process. Metasomatism by a small amount of melt/fluid enriched in LREE followed the former melt removal, which resulted in the enrichment of the incompatible trace elements. Sr and Nd isotopic ratios of the Jeju xenoliths display a wide scatter from depleted mid-oceanic ridge basalt (MORB)-like to near bulk-earth estimates along the MORB,oceanic island basalt (OIB) mantle array. The varieties in modal proportions of minerals, (La/Yb)N ratio and Sr-Nd isotopes for the xenoliths demonstrate that the lithospheric mantle beneath Jeju Island is heterogeneous. The heterogeneity is a probable result of its long-term growth and enrichment history. [source]


    The Inside Track: On the Important (But Neglected) Role of Customers in the Resource-Based View of Strategy and Firm Growth*

    JOURNAL OF MANAGEMENT STUDIES, Issue 8 2005
    Ivo Zander
    abstract This paper argues for the important role of customers as a source of competitive advantage and firm growth, an issue which has been largely neglected in the resource-based view of the firm. It conceptualizes Penrose's (1959) notion of an ,inside track' and illustrates how in-depth knowledge about established customers combines with joint problem-solving activities and the rapid assimilation of new and previously unexploited skills and resources. It is suggested that the inside track represents a distinct and perhaps underestimated way of generating rents and securing long-term growth. This also implies that the sources of sustainable competitive advantage in important respects can be sought in idiosyncratic interfirm relationships rather than within the firm itself. [source]


    Acquisition of iron from human transferrin by Porphyromonas gingivalis: a role for Arg- and Lys-gingipain activities

    MOLECULAR ORAL MICROBIOLOGY, Issue 2 2001
    V. Brochu
    Porphyromonas gingivalis, a key causative agent of adult periodontitis, is known to produce a variety of virulence factors including proteases. The aim of this study was to evaluate the participation of Arg- and Lys-gingipain activities of P. gingivalis in the acquisition of iron from human transferrin and its subsequent utilization in growth. Iron-saturated transferrin was found to support the long-term growth of P. gingivalis. Our results indicated that P. gingivalis does not produce siderophore and does not possess ferric reductase and transferrin-binding activities. Incubating transferrin with P. gingivalis resulted in degradation of the protein, a step that may be critical for the acquisition of iron from transferrin. Spontaneous and site-directed mutants of P. gingivalis deficient in one or several proteases were used to demonstrate the key role of specific enzymes in degradation of transferrin and subsequent utilization for growth. The lack of both Arg- and Lys-gingipain activities (mutants M1 and KDP128) was associated with an absence of degradation of transferrin and the incapacity of bacteria to grow in the presence of transferrin as the sole source of iron. It was also found that the Lys-gingipain activity is more critical than the Arg-gingipain activity since the mutant KDP112 (deficient in Arg-gingipain A and B) could grow whereas the mutant KDP129 (deficient in Lys-gingipain) could not. The fact that growth of mutant KDP112 was associated with a lower final optical density and a generation time much longer compared with the parent strain suggests that the Arg-gingipain activity also participates in the acquisition of iron from transferrin. Selected inhibitors of cysteine proteases (TLCK, leupeptin and cathepsin B inhibitor II) were tested for their capacity to reduce or inhibit the growth of P. gingivalis under different iron conditions. All three inhibitors were found to completely inhibit growth of strain ATCC 33277 in a medium supplemented with transferrin as the source of iron. The inhibitors had no effects when the bacteria were grown in a medium containing hemin instead of transferrin. The ability of P. gingivalis to cleave transferrin may be an important mechanism for the acquisition of iron from this protein during periodontitis. [source]


    Strength of asymmetric competition between predators in food webs ruled by fluctuating prey: the case of foxes in tundra

    OIKOS, Issue 1 2010
    John-André Henden
    In food webs heavily influenced by multi-annual population fluctuations of key herbivores, predator species may differ in their functional and numerical responses as well as their competitive ability. Focusing on red and arctic fox in tundra with cyclic populations of rodents as key prey, we develop a model to predict how population dynamics of a dominant and versatile predator (red fox) impacted long-term growth rate of a subdominant and less versatile predator (arctic fox). We compare three realistic scenarios of red fox performance: (1) a numerical response scenario where red fox acted as a resident rodent specialist exhibiting population cycles lagging one year after the rodent cycle, (2) an aggregative response scenario where red fox shifted between tundra and a nearby ecosystem (i.e. boreal forest) so as to track rodent peaks in tundra without delay, and (3) a constant subsidy scenario in which the red fox population was stabilized at the same mean density as in the other two scenarios. For all three scenarios it is assumed that the arctic fox responded numerically as a rodent specialist and that the mechanisms of competition is of a interference type for space, in which the arctic fox is excluded from the most resource rich patches in tundra. Arctic fox is impacted most by the constant subsidy scenario and least by the numerical response scenario. The differential effects of the scenarios stemmed from cyclic phase-dependent sensitivity to competition mediated by changes in temporal mean and variance of available prey to the subdominant predator. A general implication from our result is that external resource subsidies (prey or habitats), monopolized by the dominant competitor, can significantly reduce the likelihood for co-existence within the predator guild. In terms of conservation of vulnerable arctic fox populations this means that the likelihood of extinction increases with increasing amount of subsidies (e.g. carcasses of large herbivores or marine resources) in tundra and nearby forest areas, since it will act to both increase and stabilize populations of red fox. [source]


    Long-term growth of soybean at elevated [CO2] does not cause acclimation of stomatal conductance under fully open-air conditions

    PLANT CELL & ENVIRONMENT, Issue 9 2006
    ANDREW D. B. LEAKEY
    ABSTRACT Accurately predicting plant function and global biogeochemical cycles later in this century will be complicated if stomatal conductance (gs) acclimates to growth at elevated [CO2], in the sense of a long-term alteration of the response of gs to [CO2], humidity (h) and/or photosynthetic rate (A). If so, photosynthetic and stomatal models will require parameterization at each growth [CO2] of interest. Photosynthetic acclimation to long-term growth at elevated [CO2] occurs frequently. Acclimation of gs has rarely been examined, even though stomatal density commonly changes with growth [CO2]. Soybean was grown under field conditions at ambient [CO2] (378 µmol mol,1) and elevated [CO2] (552 µmol mol,1) using free-air [CO2] enrichment (FACE). This study tested for stomatal acclimation by parameterizing and validating the widely used Ball et al. model (1987, Progress in Photosynthesis Research, vol IV, 221,224) with measurements of leaf gas exchange. The dependence of gs on A, h and [CO2] at the leaf surface was unaltered by long-term growth at elevated [CO2]. This suggests that the commonly observed decrease in gs under elevated [CO2] is due entirely to the direct instantaneous effect of [CO2] on gs and that there is no longer-term acclimation of gs independent of photosynthetic acclimation. The model accurately predicted gs for soybean growing under ambient and elevated [CO2] in the field. Model parameters under ambient and elevated [CO2] were indistinguishable, demonstrating that stomatal function under ambient and elevated [CO2] could be modelled without the need for parameterization at each growth [CO2]. [source]


    Under Performers and Over Achievers: A Quantile Regression Analysis of Growth

    THE ECONOMIC RECORD, Issue 248 2004
    Raul A. Barreto
    Numerous papers have searched for empirical linkages between long run economic growth and a myriad of economic, socio-political and environmental factors. Most of these studies use ordinary least-squares regression or panel regression analysis on a sample of countries and therefore consider the behaviour of growth around the mean of the conditional distribution. We extend the literature by using quantile regression to analyse long-term growth at a variety of points in the conditional distribution. By using this approach, we identify the determinants of growth for under performing countries relative to those for over achieving countries. [source]


    The nature of market visioning for technology-based radical innovation

    THE JOURNAL OF PRODUCT INNOVATION MANAGEMENT, Issue 4 2001
    Gina Colarelli O'Connor
    The ability to link advanced technologies to market opportunities is a crucial aspect of radical innovation. When markets do not yet exist, it is difficult to persevere, given organizational pressures for immediate profit. To study this problem, eleven radical innovation projects are examined in nine large, mature organizations in a real-time field setting. The sample is augmented by interviews of four additional individuals who have repeated experiences in linking advanced technologies to markets. From results that are qualitative in nature, four themes emerge. First, vision is built and sustained through a variety of mechanisms that may operate in combination or serially. Second, there are a number of roles that individuals play in creating and evangelizing a vision through an organization. Third, there exist a few tools and methods for aiding in developing visions that are not dependent strictly on individual initiative, but these are not systematically employed by organizations. Finally, visions undergo a process of validation and internal acceptance that may depend heavily on reaching out beyond the familiar customer/market set of the firm. Building on these themes, we derive two sets of insights. The first identifies three different ways that visions might develop. We did not discover a singular process across firms or even within a single firm by which visions develop. Second, we identify three elements that occur when a vision is formulated and utilized in organizations: Motivation, Insight and Elaboration. Thus a vision does not arise through a single creative leap, but develops over time and requires focus, discipline, energy, and the involvement of many people. Awareness of this conceptual underpinning of visioning may help managers understand how to encourage this activity and help sustain long-term growth and renewal in their organizations. [source]


    National Health Service Corps Staffing and the Growth of the Local Rural Non-NHSC Primary Care Physician Workforce

    THE JOURNAL OF RURAL HEALTH, Issue 4 2006
    Donald E. Pathman MD
    ABSTRACT:,Context: Beyond providing temporary staffing, National Health Service Corps (NHSC) clinicians are believed by some observers to contribute to the long-term growth of the non-NHSC physician workforce of the communities where they serve; others worry that NHSC clinicians compete with and impede the supply of other local physicians. Purpose: To assess long-term changes in the non-NHSC primary care physician workforce of rural underserved counties that have received NHSC staffing support relative to workforce changes in underserved counties without NHSC support. Methods: Using data from the American Medical Association and NHSC, we compared changes from 1981 to 2001 in non-NHSC primary care physician to population ratios in 2 subsets of rural whole-county health professional shortage areas: (1) 141 counties staffed by NHSC physicians, nurse practitioners, and/or physician assistants during the early 1980s and for many of the years since and (2) all 142 rural health professional shortage area counties that had no NHSC clinicians from 1979 through 2001. Findings: From 1981 to 2001, counties staffed by NHSC clinicians experienced a mean increase of 1.4 non-NHSC primary care physicians per 10,000 population, compared to a smaller, 0.57 mean increase in counties without NHSC clinicians. The finding of greater non-NHSC primary care physician to population mean ratio increase in NHSC-supported counties remained significant after adjusting for baseline county demographics and health care resources (P < .001). The estimated number of "extra" non-NHSC physicians in NHSC-supported counties in 2001 attributable to the NHSC was 294 additional physicians for the 141 supported counties, or 2 extra physicians, on average, for each NHSC-supported county. Over the 20 years, more NHSC-supported counties saw their non-NHSC primary care workforces grow to more than 1 physician per 3,500 persons, but no more NHSC-supported than nonsupported counties lost their health professional shortage area designations.Conclusions: These data suggest that the NHSC contributed positively to the non-NHSC primary care physician workforce in the rural underserved counties where its clinicians worked during the 1980s and 1990s. [source]


    UNCERTAINTY, LEARNING AND GROWTH

    THE MANCHESTER SCHOOL, Issue 5 2008
    RAGCHAASUREN GALINDEV
    The paper extends Blackburn and Galindev's (Economics Letters, Vol. 79 (2003), pp. 417,421) stochastic growth model in which productivity growth entails both external and internal learning behaviour with a constant relative risk aversion utility function and productivity shocks. Consequently, the relationship between long-term growth and short-term volatility depends not only on the relative importance of each learning mechanism but also on a parameter measuring individuals' attitude towards risk. [source]


    A novel, spontaneously immortalized, human prostate cancer cell line, Bob, offers a unique model for pre-clinical prostate cancer studies,

    THE PROSTATE, Issue 14 2009
    Gerhardt Attard
    Abstract INTRODUCTION New in vitro models of castration-resistant prostate cancer (CRPC) are urgently required. METHODS Trans-rectal needle biopsies (TRBP) of the prostate were performed for research purposes on progressing CRPC patients who had not received prior treatment to the prostate. Biopsies were immediately digested with collagenase and plated onto collagen-coated flasks with a feeder layer of 3T6 cells and cultured in cytokine-supplemented keratinocyte serum-free medium. RESULTS Biopsies from 25 patients were collected and one of these, following an initial period of crisis, spontaneously immortalized. A series of cell lines called Bob were then established from a clone that survived CD133-selection followed by 4 weeks under adhesion-independent conditions in methylcellulose. Gains and losses previously described in clinical prostate tumors, most notably loss of 8(p) and gain of 8(q), were identified on comparative genomic hybridization and long-term growth in culture, survival in methylcellulose and invasion through matrigel confirmed the malignant phenotype of Bob. Furthermore, Bob expressed high levels of p53 and markers of early differentiation, including K8, prostatic acid phosphatase and prostate stem cell antigen. There was, however, no in vivo growth and ERG and ETV1 were not rearranged. Growth in serum permitted some differentiation. CONCLUSION This is the first spontaneously immortalized prostate cancer cell line to be established from a TRBP of a patient with CRPC. Bob is a novel pre-clinical model for functional studies in CRPC and especially for studying the CRPC "basal" phenotype. Prostate 69: 1507,1520, 2009. © 2009 Wiley-Liss, Inc. [source]


    Sustained Growth of Explants from Mediterranean Sponge Crambe crambe Cultured In Vitro with Enriched RPMI 1640

    BIOTECHNOLOGY PROGRESS, Issue 3 2006
    F. Garcia Camacho
    Marine sponges are potential sources of many unique metabolites, including cytotoxic and anticancer compounds. Natural sponge populations are insufficient or inaccessible for producing commercial quantities of metabolites of interest. It is commonly accepted that tissue (fragments, explants, and primmorphs) and in vitro cell cultivation show great potential. However, there is little knowledge of the nutritional requirements of marine sponges to carry out efficient and sustained in vitro culture and progress has been slow. In marine invertebrate fila many unsuccessful attempts have been made with in vitro cultures using typical commercial animal cell media based on sources of dissolved organic carbon (DOC) (e.g., DMEM, RPMI, M199, L-15, etc.). One of the reasons for this failure is the use of hardly identifiable growth promoters, based on terrestrial animal sera. An alternative is the use of extracts from marine animals, since they may contain nutrients necessary for growth. In this work we have cultivated in vitro explants of the encrusting marine sponge Crambe crambe. It is one of the most abundant sponges on the Mediterranean coastline and also possesses an array of potentially active metabolites (crambines and crambescidins). Initially a new approach was developed in order to show consumption of DOC by explants. Thus, different initial DOC concentrations (300, 400, 700 and 1200 mg DOC L,1) were assayed. Consumption was evident in all four assays and was more marked in the first 6 h. The DOC assimilation data were adjusted to an empirical model widely used for uptake kinetics of organic dissolved compounds in marine invertebrates. Second, a protocol was established to cultivate explants in vitro. Different medium formulations based on RPMI 1640 commercial medium enriched with amino acids and inorganic salts to emulate seawater salinity were assayed. The enrichment of this medium with an Octopusaqueous extract in the proportions of 10% and 20% (v/v) resulted in an evident sustained long-term growth of C. crambe explants. This growth enhancement produced high metabolic activity in the explants, as is confirmed by the high ammonium and lactate content in the medium a few days after its renewal and by the consumption of glucose. The lactate accumulation increased with the size and age of explants. Prior to these experiments, we successfully developed a robust new alternative method, based on digital image treatment, for accurate determination of the explant apparent volume as growth measure. [source]


    Growth of NS0 Cells in Protein-Free, Chemically Defined Medium

    BIOTECHNOLOGY PROGRESS, Issue 5 2000
    Stephen Gorfien
    Many hybridoma and recombinant myeloma cell lines have been successfully adapted to growth in protein-free media. Compared with serum-supplemented media, use of protein-free media promotes superior cell growth and protein expression and facilitates downstream purification of the expressed product. Owing to its sterol auxotrophy, the NS0 myeloma is normally grown in either a serum-supplemented medium or a serum-free medium supplemented with an animal-derived lipoprotein. CD Hybridoma Medium (a protein-free, chemically defined formulation) grows many cell lines that do not exhibit lipid dependence, but this medium does not support growth of NS0 cells without further lipid supplementation. We tested several commercially available lipid supplements in CD Hybridoma Medium, including bovine EX-CYTE VLE. None of the tested supplements supported long-term growth of NS0 cells in CD Hybridoma Medium. Sustained long-term growth of NS0 cells was achieved in CD Hybridoma Medium supplemented with various animal- or plant-derived lipids complexed with cyclodextrin. NS0 cells adapted to CD Hybridoma Medium supplemented with cyclodextrin-lipid complex reached peak cell densities that were more than double those observed in serum-supplemented medium and were cultured for more than 15 passages. These cultures were also successfully cryopreserved and recovered in this defined medium. Through the use of cyclodextrin-based additives to CD Hybridoma Medium, it is possible to solubilize significant quantities of sterols and other lipids and to maintain a protein-free, chemically defined cultivation environment for NS0 cells. The culture system can be kept entirely free of animal-derived components if the supplement is made with plant-derived or synthetic lipids. [source]


    Price Rigidities, Inflationary Finance and Long-run Growth*

    BULLETIN OF ECONOMIC RESEARCH, Issue 1 2000
    Christopher Tsoukis
    The paper considers a monopolistically competitive intertemporally optimizing monetary economy featuring long-term growth. Inflation is generated through sluggish price-setting and contributes to budgetary finance through seignorage. This setup permits exploration of the interaction between inflation and growth in a tractable way. Superneutrality holds in the long but not the short run. The budget deficit fuels inflation with a hysteresis. Growth and inflation are negatively correlated in the long run, with causality running from the former to the latter, and positively correlated in the short run regardless of the origin of shocks. Price flexibility precipitates adjustment but appears also to destabilize output. [source]


    Growth after ventricular septal defect repair: does defect size matter?

    ACTA PAEDIATRICA, Issue 9 2010
    A 10-year experience
    Abstract Aim:, To evaluate whether the ventricular septal defect (VSD) size, along with the degree of preoperative growth impairment and age at repair, may influence postoperative growth, and if VSD size can be useful to identify children at risk for preoperative failure to thrive. Methods:, Sixty-eight children submitted to VSD repair in a Brazilian tertiary-care institution were evaluated. Weight and height measurements were converted to Z -scores. Ventricular septal defect size was normalized by dividing it by the aortic root diameter (VSD/Ao ratio). Results:, Twenty-six patients (38%) had significantly low weight-for-height, 10 patients (15%) had significantly low height-for-age and 13 patients (19%) had both conditions at repair. Catch-up growth occurred in 82% of patients for weight-for-age, in 75% of patients for height-for-age and in 89% of patients for weight-for-height. Weight-for-height Z -scores at surgery were significantly lower in patients who underwent repair before 9 months of age. The VSD/Ao ratio did not associate with any other data. On multivariate analysis, weight-for-age Z -scores and age at surgery were independent predictors of long-term weight and height respectively. Conclusion:, The VSD/Ao ratio was not a good predictor of preoperative failure to thrive. Most patients had preoperative growth impairment and presented catch-up growth after repair. Preoperative growth status and age at surgery influenced long-term growth. [source]


    Cytokine levels in neonatal necrotizing enterocolitis and long-term growth and neurodevelopment

    ACTA PAEDIATRICA, Issue 3 2010
    A Lodha
    Abstract Objective:, To investigate if circulating cytokines are related to growth and neurodevelopmental outcome following necrotizing enterocolitis (NEC). Study design:, Pro-inflammatory cytokine levels were measured prospectively in 40 neonates and compared with neurodevelopmental outcome. Cytokine levels were measured at the onset of feeding intolerance (Group II, n = 17) or NEC (Group III, n = 10) and at weeks 2,3 in control infants (Group I, n = 13). Neurodevelopmental outcome was assessed at the age of 24,28 months. Data were analysed using descriptive statistics, non-parametric tests and Student t -test. Results:, Median birth weights (range) in groups I, II and III were 1120 (525,1564) g, 1068 (650,1937) g and 1145 (670,2833) g, and median gestational ages (range) were 28 (24,35) weeks 28 (24,35) weeks and 28 (25,37) weeks respectively. NEC occurred in 10 infants. Serum IL-6 (interleukin-6) was elevated in group III, (p = 0.03). Significant developmental delay was found in 12% of the infants in Group II and 20% of the infants in Group III, but no infant in group I. Five infants in group III with NEC (50%), had head ultrasound abnormalities. At 1 year of age, growth, weight and head circumference were significantly different in Group III, however, at two years of age, only height was significantly different, p < 0.02. Although there was wide variation, neonatal cytokine levels tended to be greater in the infants later found to have abnormal cognitive and psychomotor outcomes. Conclusion:, This study suggests that increased serum levels of pro-inflammatory cytokines may play a role in the poor growth and neurodevelopment associated with this high-risk population. [source]


    China and the Global Financial Crisis: Assessing the Impacts and Policy Responses

    CHINA AND WORLD ECONOMY, Issue 3 2010
    Yan Liang
    F40; O11; O53 Abstract The present paper explores the role of China in the creation of the current global financial crisis and the impacts of the crisis on its economy. It argues against the view that the "saving glut" in China (along with other Asian emerging economies) played a significant causal role in the crisis. The global financial crisis did not engender much damage in China's financial structure, thanks to the relatively closed, bank-centered financial system. However, the impacts on the "real" side of the Chinese economy were hard felt. Growth and employment have fallen, largely due to the decline in exports and foreign direct investment. The crisis reveals the vulnerability of the export-dependent growth pattern. Policy responses of the Chinese Government, including monetary, fiscal and social policies, have helped to stem the downfall of the economy in the immediate term, but some of the policies have not addressed the structural problems of the Chinese economy and might well aggravate such problems over time. The present paper proposes a tentative reform blueprint to rebalance the economy and to sustain long-term growth. [source]