Low Growth Potential Research Articles

Seed Biology of the Invasive Species Buffalobur (Solanum rostratum) in Northwest China

Buffalobur is an invasive summer annual species in Xinjiang Province, China. Our purpose was to investigate certain aspects of the seed biology of this weedy species that might be useful in controlling it. In contrast to a previous report that fresh seeds have physical (water-impermeable seed coat) plus physiological (low growth potential of embryo) dormancy, our results, along with those of others, verify that the seeds have only physiological dormancy. The seed's coat is water-permeable, the embryo is fully developed at seed maturity, and dormancy can be broken by cold stratification in the field during winter and early spring. Fifty-five percent of seeds buried in the soil in autumn germinated in the soil the following May, and 53% of the remaining nongerminated seeds germinated when tested in light in the laboratory. Thus, about 20% of the seeds did not germinate but were viable, demonstrating that the species forms at least a short-lived persistent seed bank. This information will be useful in planning a management strategy for this highly invasive species in northwest China.

Unravelling the effects of water temperature and density dependence on the spatial variation of brown trout (Salmo trutta) body size

This study looks at the relative influence of water temperature and density dependence on the spatial variation in body size of 126 brown trout ( Salmo trutta ) cohorts from 12 Iberian rivers over a 12-year period. Mean cohort mass and length of age groups 0+ to 2+ varied significantly among sampling sites because of the concurrent effect of water temperature and density dependence. Density in suitable habitat had a limiting role that influenced potential maximum growth of cohorts, and water temperature differentiated these cohorts in two groups of sites with high and low potential maximum growth. Water temperature had a positive cumulative effect on body size of all age classes. However, body size of age-0 trout was nonlinearly influenced by short-term exposure to extreme water temperature. Thus, extremely high temperatures became a limiting factor and had deleterious effects on growth. There were intracohort and intercohort effects of density dependence throughout the life span, which were mainly due to the density in the available suitable habitat of trout of the same age or older. The present study supports the hypothesis that both density-dependent and density-independent processes are crucial for the understanding of population dynamics and that their relative importance varies across scales of space and time.

Abstract P242: Adenylate Kinase 2 Deficiency Disrupts Mitochondrial Energetics, AMP Metabolic Signaling, and Metabolomic Response to Myocardial Stress

Adenylate kinase 2 (AK2) isoform in mitochondrial intermembrane/intracristal space provides a conduit facilitating ATP export and delivery to cellular ATPases. AK2+/- transgenic mice is viable while homozygous AK2-/- deficiency results in midgestation embryonic lethality. AK2-/- mouse embryonic fibroblasts (MEFs) have severely disrupted mitochondrial cristae structure and display low growth and proliferation potential. Protein knockdown using siRNA indicates that AK2 is critical for cardiomyocyte mitochondrial biogenesis and network formation. Transgenic AK2+/- hearts display greater changes in AMP/ATP ratio and AMPK activation during ischemia compared to wild type suggesting deficient tuning of AMP signals. Metabolomic profile of AK2+/- hearts subjected to myocardial ischemia indicate lower ability to maintain adenine and guanine nucleotide pools. AK2+/- mice have abnormal metabolomic response to treadmill exercise compared to wild type. Metabolomic profiling revealed that most significant plasma metabolites critical in the discrimination between wild type and AK2+/- phenotypes were adenosine, tyrosine, tryptophan and hypoxanthine indicating lower energetic potential of AK2+/- mice. AK2+/- hearts have increased mitochondrial creatine kinase CKmit content which could be viewed as a compensatory mechanism. Thus, AK2 is the first phosphotransfer enzyme which deficiency causes embryonic lethality indicating critical significance of catalyzed nucleotide exchange and conductive transfer in the narrow and crowded mitochondrial intermembrane/intracristal space.

Does the Management's Forecast of Merger Synergies Explain the Premium Paid, the Method of Payment, and Merger Motives?

I study a sample of 336 mergers and acquisitions (M&A) deals to investigate the effect of managements’ estimate of synergy on the reservation price and the payment method. I find that synergy does not explain the premium paid implying that it may have been announced to induce shareholders to endorse the deal. Acquiring firms are more likely to overpay if they have low growth potential, while the target firm is large, has higher premerger operating performance, and high growth potential. Acquirers may be serving their own self‐interests as they are more likely to exceed their reservation price if they receive low compensation and if entrenchment provisions are in place. I also find that these acquisitions lead to postmerger shareholders’ wealth destruction, which is more pronounced when acquirers overpay. I document that the greater the synergy and the acquirer firm‐specific overvaluation, the higher the likelihood of settling the deal with more shares.

The Impact of RFID Adoption on the Market Value of Firms: An Empirical Analysis

Extant research praises the benefits of radio frequency identification (RFID) on the basis of case studies and experience reports. However, empirical studies that access the strategic impact of RFID on organizations are rare, and the financial impact of RFID adoption on the firms remains unclear. This article provides empirical evidence related to the effect of RFID adoption on market value of firms by examining short-term market reaction toward RFID adoption. Based on 108 publicly traded firms that adopt RFID, we find that RFID adoption has a statistically significant negative impact on a firm's market value. The stock price of the firm decreases by at least 0.29% on the day of the announcement, indicating that the investors perceive RFID adoption announcements to be bad news for most firms. Moreover, the subsampling analysis indicates that US-based firms, late adopters, nonmanufacturing firms, less diversified firms, financially unhealthy firms, and low growth potential firms suffer more negative impact when they announce the news of RFID adoption. Overall, this article adds to the accumulating evidence about the risks that accompany a disruptive IT like RFID and provides a note of caution to firms that are interested to invest in RFID.

Shifting threats faced by the San Clemente sage sparrow

AbstractThreats to a species' persistence are likely to change as conservation measures reduce some threats, while natural and anthropogenic changes increase others. Despite a variety of potential underlying mechanisms, extinction threats will be manifested through one of the 3 components of population dynamics: reducing population growth potential, increasing population variability, or lowering the population ceiling. Consequently, effective management can be guided by monitoring programs and population models that examine each of these components. We examined the potential for a coupled monitoring and modeling effort to guide management of species‐at‐risk while accounting for evolving risks using the case study of the threatened San Clemente sage sparrow (Amphispiza belli clementeae). Originally listed due to a low population ceiling imposed by severe habitat loss, we found that the major threat to San Clemente sage sparrow persistence has shifted to low population growth potential driven by high juvenile mortality. We further found that successful mitigation of high juvenile mortality will shift the primary threat to drought frequency, which is predicted to increase on San Clemente Island as a consequence of global climate change. The latter shift is a consequence of the boom‐bust ecology exhibited by San Clemente sage sparrows in response to rainfall—likely a common characteristic of short‐lived terrestrial vertebrates in arid environments. Our ability to successfully recover this species hinges on a comprehensive monitoring and modeling program incorporating all 3 components of population dynamics informing changes in management priorities to reflect shifting threats. Our study indicates that the next critical step to recovering sage sparrows is to understand and mitigate the causes of high juvenile mortality. In response to these predictions, the United States Navy has funded a radio‐telemetry study to determine the cause(s) of juvenile mortalities. © 2011 The Wildlife Society.

Impact of the Crisis on Potential Growth: An Approach Based on Unobserved Component Models (in French)

This article aims at evaluating potential growth for France, Germany and the euro area during the period from after the 2007-2008 credit crisis until 2012. Such an assessment plays a central role in the determination of the structural deficit and therefore in the definition of consolidation plans. After presenting the possible effects of the crisis on potential growth identified by the literature, we use for our evaluations an unobserved component model. This helps to reconcile the so-called traditional approaches, based on the use of a production function and the statistical approaches based on filtering methods. Our evaluations show for the different areas that the crisis has had a significant impact on potential growth starting in 2009; by 2012, potential growth should remain weak. The low potential growth is caused in part by a sharp decline in labor input, particularly in France and the euro area. This decline stems mainly from an increase of structural unemployment, except in Germany.

The role of macroeconomic policies in the global crisis

This paper argues that the lack of timely and decisive policy action to correct domestic and external imbalances contributed crucially to the build-up of financial excesses that led to the financial crisis and the Great Recession. We focus on 2002–2007 and perform a number of counterfactual simulations to investigate two central elements of the story, namely: (a) an over-expansionary US monetary policy and the absence of effective macro-prudential supervision, which permitted a prolonged expansion of debt-financed consumer spending and (b) the choice by China and other emerging countries to pursue an export-led growth strategy supported by pegging their currencies to the US dollar, in conjunction with sluggish domestic demand in major advanced economies characterized by low potential output growth. The results of the simulations lend support to the view that if substantial, globally coordinated demand rebalancing had been undertaken early on, the macroeconomic and financial imbalances would not have accumulated to the extent that they did and the financial turmoil might have had less drastic global consequences.

Are fungi important for breaking seed dormancy in desert species? Experimental evidence in Opuntia streptacantha (Cactaceae)

Seeds of Opuntia spp. have physiological dormancy; they need a period of after-ripening to break dormancy, and the embryos have low growth potential. We evaluated the combined effects of seed age and presence of fungi on the testa on germination of Opuntia streptacantha, an abundant species in the Chihuahuan Desert (Mexico), assuming that older seeds have broken seed dormancy and fungi can reduce mechanical resistance to germination. In a preliminary experiment, we found no germination of 9-year-old (1998) and freshly collected (2007) seeds. However, we obtained 67% and 27% germination from 9-year-old and fresh non-sterilized seeds, respectively, and found fungi growing on the testa of all germinated seeds. Two fungal strains were isolated and identified using ribosomal internal transcribed spacer (ITS) sequence analysis: Penicillium chrysogenum and Phoma sp. In a second experiment, we inoculated seeds with strains of P. chrysogenum and Phoma sp., as well as Trichoderma koningii and binucleate Rhizoctonia (Gto17S2), to evaluate their ability to break seed dormancy. Seeds inoculated with P. chrysogenum, Phoma sp. and T. koningii had higher germination than controls for both seed ages, but germination was higher in older seeds. Scanning electron microscopy showed that these fungi eroded the funiculus, reducing its resistance. Binucleate Rhizoctonia did not lead to germination and controls had almost no germination. Our results strongly indicate that fungi are involved in breaking seed dormancy of O. streptacantha, and that the effect of fungi on seeds is species-specific.

The Role of Macroeconomic Policies in the Global Crisis

This paper argues that the lack of timely and decisive policy action to correct domestic and external imbalances contributed crucially to the build-up of financial excesses that led to the financial crisis and the Great Recession. We focus on 2002-07 and perform a number of counterfactual simulations to investigate two central elements of the story, namely: (a) an over-expansionary US monetary policy and the absence of effective macro-prudential supervision, which permitted a prolonged expansion of debt-financed consumer spending; (b) the decision of China and other emerging countries to pursue an export-led growth strategy supported by pegging their currencies to the US dollar, resulting in a huge build-up of their official reserves, in conjunction with sluggish domestic demand in surplus advanced economies characterized by low potential output growth. The results of the simulations lend support to the view that if substantial, globally coordinated demand rebalancing had been undertaken in a timely manner, the macroeconomic and financial imbalances would not have accumulated to the extent that they did and the financial turmoil might have had less drastic global consequences.

Population Differentiation and Climatic Adaptation for Growth Potential of White Spruce (Picea glauca) in Alberta, Canada

Abstract Genetic differentiation among white spruce populations in Alberta, Canada, was studied using time series data of height and diameter and a climatic index developed by principal component analysis. The objectives were to discern patterns of variation for growth potential and predicted optimum climate; compare optimum climate between populations, between height and diameter at the same age and between height or diameter at different ages; and to see if optimum climate differed from the climate inhabited by populations. Using cluster analysis we found that: (1) populations from mid-latitudes (54° - 57°N) and mid-elevations (600 - 800 m) were grouped together and exhibited high growth potential; populations from north of 57°N were grouped with those from elevations higher than 900m in the Rocky Mountains and exhibited low growth potential; and (2) With minor exceptions, populations from similar climates or geography were grouped together in terms of predicted optimum climate. (3) Analysis of variance showed that optimum climate differed significantly (P < 0.05) among populations; among heights at different ages; among diameters at different ages and between height and diameter at the same ages. However, there was no consistent trend in the direction of change in optimum climate with tree age. (4) The range of climate inhabited by the populations (PI₁ = -5.792 to 4.483) was much wider than the range of their predicted optimum climate (P̂Ō₁ = -1.001 to 0.842), which suggests that in terms of growth potential some populations inhabit sub-optimal climates. Implications of the results on management of white spruce in Alberta are discussed.

The New Medium-Term Budgetary Objectives and the Problem of Fiscal Sustainability after the Crisis

The paper analyses the medium-term objectives (MTOs) recently adopted by the EU Member States as a reference for the multilateral budgetary surveillance, assessing the ability of the new MTOs to promote long-term fiscal sustainability. The paper calibrates the (yet undisclosed) algorithm for computing the minimum budgetary targets that EU countries can declare as MTO and discusses two novel features of the algorithm: a supplementary debt-reduction effort requested from high-debt countries, and the partial frontloading of the expected future increases in age-related expenditure -the cost of ageing-. The paper evaluates the impact of the crisis on EU countries‟ current as well as future MTOs through the channels of higher public debt, lower growth potential, and higher cost of ageing. On the basis of alternative scenarios for macroeconomic and budgetary conditions as of 2012 -when the next revision of MTOs is scheduled-, the paper concludes that prospective MTOs would be more stringent than the current ones. Therefore, a path for gradual fiscal tightening is already embedded into the European fiscal framework and should be considered when discussing exit strategies. Finally, an alternative indicator linking MTOs to the current fiscal and financial imbalances is presented.

Intra-specific variation in pea responses to ammonium nutrition leads to different degrees of tolerance

The form of nitrogen nutrition affects many biochemical and physiological processes in plants, leading to markedly different growth responses. Many plant species have been characterized as ammonium tolerant or sensitive. The objective of this work was to assess the range of physiological adaptative responses involved in tolerance of ammonium nutrition at the intra-specific level. Pisum sativum L. was selected as a model of tolerance for the study, and four varieties of agricultural importance (Snap-pea, Rondo, Tristar and Eclipse) were grown hydroponically with ammonium or nitrate (0.5, 2.5, 5.0 and 10.0 mM) as the sole nitrogen source. Physiological parameters including photosynthesis, respiration and ammonium contents were analyzed. Activities/expression of key enzymes of the nitrogen metabolism was also determined, for which novel antibodies against glutamate dehydrogenase and glutamine synthetase were obtained. Snap-pea was considered a reference plant for ammonium tolerance, since its biomass accumulation was not affected by nitrogen source. It avoided the physiological effects of ammonium through low growth potential, high respiratory rates and activity of the alternative pathway. A multivariate analysis of the results showed that each of the four varieties had distinct adaptative responses to ammonium nutrition, highlighting the flexibility of response to ammonium nutrition at the species level. A general activation of glutamate dehydrogenase (GDH) was observed, regardless of the degree of tolerance to ammonium, which may be due to GDH being part of a common stress response to carbon deficit rather than an ammonium tolerance mechanism.

Identification of a Common Gene Expression Signature Associated with Immature Clonal Mesenchymal Cell Populations Derived from Bone Marrow and Dental Tissues

Mesenchymal stem/stromal cell-like populations derived from adult bone marrow (BMSC), dental pulp (DPSC), and periodontal ligament (PDLSC) have the ability to differentiate into cells of mesenchymal and non-mesenchymal tissues in vitro and in vivo. However, culture-expanded MSC-like populations are a heterogeneous mix of stem/committed progenitor cells that exhibit altered growth and developmental potentials. In the present study we isolated and characterized clonal populations of BMSCs, DPSCs, and PDLSCs to identify potential biomarkers associated with long-lived multipotential stem cells. Microarray analysis was used to compare the global gene expression profiles of high growth/multipotential clones with low growth potential cell clones derived from 3 stromal tissues. Cross-comparison analyses of genes expressed by high growth/multipotential clones derived from bone marrow, dental pulp, and periodontal ligament identified 24 genes that are differentially up-regulated in all tissues. Notably, the transcription factors, E2F2, PTTG1, TWIST-1, and transcriptional cofactor, LDB2, each with critical roles in cell growth and survival, were highly expressed in all stem cell populations examined. These findings provide a model system for identifying a common molecular fingerprint associated with immature mesenchymal stem-like cells from different organs and implicate a potential role for these genes in MSC growth and development.

Effects of autochthonous microbial community on the die-off of fecal indicators in tropical beach sand

The recently observed high levels of fecal indicators in beach sand confound beach water monitoring efforts. The high levels of fecal indicators may be caused by the loss or the reduced activities of common environmental stresses controlling die-off in the sand. Microcosm experiments were conducted to compare the effects of biotic stresses from autochthonous sand bacteria, protozoa, and viruses on Escherichia coli and Enterococcus faecalis in two tropical beach sands. The inhibition of protozoan activities by cycloheximide did not significantly affect the die-off of E. coli, indicating that protozoan predation played a limited role in beach sand. The contribution from phage infection to E. coli die-off was also negligible. Consequently, autochthonous bacteria were identified as the predominant biotic stress to the die-off of E. coli in beach sand. Subsequent experiments demonstrated that the beach sand had a very low protozoan concentration and low protozoan growth potential when compared with various environmental samples. Co-culturing of E. coli with autochthonous sand bacterial isolates significantly enhanced E. coli die-off. PCR-denaturing gradient gel electrophoresis analysis revealed a complex sand bacterial community, suggesting that bacterial antagonistic effects may be widespread. The study also found that E. faecalis exhibited a much longer survival in beach sand compared with E. coli.

Cell culture and senescence in uterine fibroids

The in vitro growth of cells from uterine fibroids is characterized by an early onset of senescence. Often, an even lower growth potential than that of matching myometrial cells is noted. Also, the tremendous differences in the expression of the high mobility group protein HMGA2 seen when comparing fibroids of different genetic subtypes are surprisingly not reflected by significant differences in their growth potential in vitro. We aimed to evaluate possible changes of the HMGA2 expression level between the native tissue and cell cultures, so we performed quantitative real-time polymerase chain reaction studies that revealed a marked decrease of the HMGA2 mRNA in culture in those cases with overexpression of HMGA2. In the two cases initially showing the highest expression, it decreased by approximately 97%. Associated with the decrease of HMGA2 was a clearly increased expression of the senescence-associated p19 Arf. Together, these findings explain the similar behavior of cell cultures from fibroids of different genetic subgroups and may also offer an explanation for the early onset of in vitro senescence in these cell cultures.

Resources, supplier investment, product launch advantages, and first product performance

Successfully launching its first product is critical to a new venture's continued success, yet the new venture has relatively few financial or human resources to support its marketing or R&D activities. It is thus important for the new venture to attract funding from external investors such as suppliers. Although the operations management (OM) literature addresses product development and supplier involvement in large firms, few studies have examined the relationship between suppliers and new ventures. This study examines how new ventures can complement their resources and experience with supplier investment, to build positional advantages for their first product and increase marketplace performance. We integrate the OM and entrepreneurship literatures to develop a model based on the resource-based view of the firm, in which the new venture uses external and internal resources to achieve positional advantages of product innovativeness, supplier involvement in production, and product launch quality. We also investigate how market potential moderates the relationship between positional advantages and performance. We empirically test our model using data from 711 new ventures. We find that it is beneficial for a new venture to involve suppliers in production of the first product, and that market potential positively moderates the relationship of product launch quality and performance. However, the results reported here also reveal several surprising results challenging traditional views. Developing a highly innovative first product is much less, not more, important than achieving a high quality first-product launch. Increasing product innovativeness does not necessarily lead to high product performance for new ventures. For a small market with low growth potential, product innovativeness has a negative, not positive, effect on first product performance. We discuss managerial implications of our findings.

Does offshoring create value for shareholders?

We study the wealth effect of offshoring by analyzing the announcement-period returns as well as the long-run operating and stock return performance of firms that offshored their activities in the period 2000–2005. Announcement-period stock returns are positive for firms that offshore activities primarily to reduce costs but are negative for firms that offshore activities for other reasons. Also, announcement-period stock returns are higher for firms with a larger size, better operating performance, lower growth potential, and a higher cost of goods sold in the year prior to the offshoring announcement. Firms that offshore activities primarily to reduce costs enjoy improved operating and stock return performance in the years following the offshoring. Overall, our findings indicate that not all firms enjoy the benefits of offshoring; rather, only those that offshore primarily to reduce costs do.

Entry Timing and Performance under Uncertainty: Taiwanese Firms Investing in China

This study makes a contribution to the understanding of the ”when-to-make FDI” issue in the context of Asian countries. This paper relates the timing of foreign direct investment (FDI) to firm-specific and environmental factors, and examines the relationship between entry timing and performance. The findings are helpful to build more general FDI theories. This study shows that, facing environmental uncertainty in host countries, firm size, R&D intensity and type of industry are associated with entry timing. This is in line with the arguments that firms with advantages act early. Besides, firms entering a market with low growth potential are more likely to be fast follower compared to the first entrant. In addition, entry timing is positively associated with performance, suggesting that early entrants tend to have better performance in uncertain environments.

Dormancy and germination characteristics of the trimorphic achenes of Garhadiolus papposus (Asteraceae), an annual ephemeral from the Junggar Desert, China

Dormancy and germination of dimorphic achenes have been compared within and between numerous species of Asteraceae, whereas only a few such comparisons have been made with trimorphic achenes. Garhadiolus papposus is an annual ephemeral species of disturbed desert habitats that produces three kinds of achenes that differ in size, morphology, pappus development and germination requirements. Fresh central achenes germinated to 10–21% in light at 15/2 and 20/10 °C, while intermediate and peripheral achenes germinated to < 5%. Germination was enhanced by excising the embryo in peripheral but not in intermediate achenes. For peripheral and intermediate achenes, pericarps and/or phyllaries did not inhibit germination of isolated embryos, indicating that water-soluble germination inhibitors were not present in these structures. For central and intermediate achenes, germination percentage increased with duration of dry storage at room temperature. Darkness decreased germination of central and intermediate achenes, while peripheral ones, which were viable, did not germinate at any condition. These data show that 1) the three morphs differ in germination requirements, and 2) difference in germination may be caused by low growth potential of the embryo and mechanical resistance (to embryo growth) of the thick pericarp and/or lignified phyllary.