bluuebunny/crossref_metadata_2025_split huggingface dataset:
Abrupt transitions to tumor extinction: A phenotypic quasispecies model
Authors: Sardanyés Josep , Martínez Regina , Simó Carles , Solé Ricard 
Published: March 2016

AbstractBackgroundThe dynamics of heterogeneous tumor cell populations competing with healthy cells is an important topic in cancer research with deep implications in biomedicine. Multitude of theoretical and computational models have addressed this issue, especially focusing on the nature of the transitions governing tumor clearance as some relevant model parameters are tuned. In this contribution, we analyze a mathematical model of unstable tumor progression using the quasispecies framework. Our aim is to define a minimal model incorporating the dynamics of competition between healthy cells and a heterogeneous population of cancer cell phenotypes involving changes in replication-related genes (i.e., proto-oncogenes and tumor suppressor genes), in genes responsible for genomic stability, and in house-keeping genes. Such mutations or loss of genes result into different phenotypes with increased proliferation rates and/or increased genomic instabilities. Also, lethal phenotypes with mutations or loss of house-keeping genes are present in our model.ResultsDespite bifurcations in the classical deterministic quasispecies model are typically given by smooth, continuous shifts (i.e., transcritical bifurcations), we here identify an novel type of abrupt transition causing tumor extinction. Such a bifurcation, named astrans-heteroclinic, is characterized by the exchange of stability between two distant fixed points (that do not collide) involving, respectively, tumor persistence and tumor clearance. The increase of mutation and/or the decrease of the replication rate of tumor cells involves this catastrophic shift of tumor cell populations. The transient times near bifurcation thresholds are also characterized, showing a power law dependence of exponent –1 of the transients as mutation is changed near the bifurcation value.ConclusionsAn abrupt transition involving tumor clearance has been identified with a phenotypic quasispecies cancer model. This result is discussed in the context of targeted cancer therapy as a possible therapeutic strategy to force a catastrophic shift by delivering mutagenic and cytotoxic drugs inside tumor cells. Our model also reveals a novel mechanism causing a discontinuous transition given by the stability exchange of two distant fixed points, which we name as atrans-heteroclinicbifurcation.
A hot water extract of Aralia cordata activates bone marrow‐derived macrophages via a myeloid differentiation protein 88‐dependent pathway and protects mice from bacterial infection
Authors: Seo Dong‐Won , Cho Yong‐Il , Gu Suna , Kim Da‐Hee , Park Jung‐Hee , Yi Young‐Joo , Lee Sang‐Myeong 
Published: March 2016

ABSTRACTIn traditional Asian medicine, Aralia cordata (AC) is a known as a pain reliever and anti‐inflammatory drug. Although several of its biological activities have been reported, the immunomodulatory effects of a hot water extract of AC (HAC) have not yet been described. The aim of this study was to investigate whether HAC modulates the activation of macrophages, which play important roles in innate immune responses against microbial pathogens, and if so, to determine the molecular mechanisms by which HAC mediates this process. It was found that HAC activates bone marrow‐derived macrophages (BMDM) and increases amounts of nitric oxide and proinflammatory cytokines in a dose‐dependent manner. In addition, HAC was found to induce phosphorylation of NF‐κB and mitogen‐activated protein kinases (MAPKs), including c‐Jun N‐terminal kinases, extracellular signal‐regulated kinases and p38. Interestingly, these effects were absent in BMDM prepared from myeloid differentiation protein 88‐knockout mice. Polysaccharides from HAC exerted stronger immunostimulatory effects than HAC itself. Furthermore, orally administered HAC clearly enhanced clearance of the intracellular pathogen Listeria monocytogenes by boosting innate immune responses. These results demonstrate that HAC exerts immunostimulatory effects through the TLR/MyD88 and NF‐κB/MAPK signal transduction pathways.
Top‐down control as important as nutrient enrichment for eutrophication effects in North Atlantic coastal ecosystems
Authors: Östman Örjan , Eklöf Johan , Eriksson Britas Klemens , Olsson Jens , Moksnes Per‐Olav , Bergström Ulf 
Published: March 2016

Summary

Seagrass and seaweed habitats constitute hotspots for diversity and ecosystem services in coastal ecosystems. These habitats are subject to anthropogenic pressures, of which eutrophication is one major stressor. Eutrophication favours fast‐growing ephemeral algae over perennial macroalgae and seagrasses, causing habitat degradation. However, changes in top‐down control, caused by, for example, overfishing, may also have negative impacts on such habitats by decreasing grazer control of ephemeral algae. Meanwhile, systematic analyses estimating top‐down effects of predator manipulations across a wide range of studies are missing, limiting the potential use of top‐down control measures in coastal management.

Here, we review the literature on experiments that test top‐down and bottom‐up controls in seagrass Zostera marina and seaweed Fucus spp. food webs in the North Atlantic. Using meta‐analysis and meta‐regression, we compare effect sizes of consumer and nutrient manipulations on primary producers, grazers and mesopredators.

Presence of mesopredators on average doubled the biomass of ephemeral algae through trophic cascades, mainly mediated via negative effects on amphipods and isopods. Of the grazers, gastropods had twice as strong a negative effect on ephemeral algae as amphipods/isopods, but responded weakly to both predators and fertilization. In accordance with theory, top‐down effects became stronger with eutrophication.

Across studies, top‐down effects on ephemeral algae at all trophic levels are on par with eutrophication effects. However, the few studies manipulating piscivorous fish make estimates of their top‐down effects uncertain.

Synthesis and applications. Consistently strong top‐down effects in coastal ecosystems call for an integrated ecosystem perspective. Management should consider measures to improve stocks of predatory fish and reduce mesopredators for restoration and conservation of essential seagrass and seaweed habitats, thereby increasing the long‐term viability of ecosystem services from coastal habitats.
Climate drivers of seed production in Picea engelmannii and response to warming temperatures in the southern Rocky Mountains
Authors: Buechling Arne , Martin Patrick H. , Canham Charles D. , Shepperd Wayne D. , Battaglia Mike A. 
Published: March 2016

Summary

Seed production by Picea engelmannii was monitored at 13 sites distributed across a ˜670 m elevation gradient for 40 years. Time series of annual seed output was investigated for evidence of masting behaviour and trends in seed abundance over time.

We used regression models in a likelihood framework to examine climate effects on seed production for critical periods in the species' reproductive cycle.

We rigorously evaluated the performance of two gridded climate data sets, PRISM and TopoWx, before using associated variables as predictors in the seed models.

Seed production at these sites does not strictly conform to the classic masting concept. Seed abundance was highly variable over time and strongly synchronized among sites, but mast years could not be objectively identified due to intermediate levels of seed output.

Model results indicate that climate conditions across multiple years cumulatively determine reproductive output. High seed rain is associated with elevated summer temperatures in the year that seeds are dispersed, low spring snowfall in the year preceding seed dispersal when buds are initiated, and reduced spring snowfall in a so‐called priming year two years prior to seed dispersal. Low spring precipitation putatively increases growing season length and resource accumulation in seed trees.

Linear models identified significant positive trends in seed output over time. Anomalous aridity and summer warmth in the latter half of the study period were highly favourable for seed production and were associated with increases in seed abundance.

Synthesis. The increases in seed output observed in this study may promote population fitness of P. engelmannii in the face of changing climate regimes and increasing frequencies of fire‐ and insect‐related tree mortality in the Rocky Mountains. Since this species lacks a persistent seed bank, re‐colonization of disturbed areas or dispersal to shifting habitats depends on adequate production of seed by surviving trees, which according to these analyses may be moderately enhanced by current climate trends. However, some evidence also indicates that increases in seed output will ultimately be constrained by threshold high temperatures in the seed maturation year.
Functional diversity enhances silver fir growth resilience to an extreme drought
Authors: Gazol Antonio , Camarero J. Julio 
Published: March 2016

Summary

It is expected that extreme climate events such as droughts will increase in both severity and intensity as a consequence of forecasted climate change. Complementarity among tree species in resource acquisition strategy may reduce interspecific competition and increase the occurrence of facilitative interactions, resulting in an improved tree growth and resilience to extreme climatic events. However, the response of individual trees growing in more functionally diverse stands to extreme events is still under debate.

We investigate the growth response of silver fir (Abies alba) to an extreme drought event which occurred in 1985–1986 in the Central Spanish Pyrenees and how the growth and resilience of trees relate to their neighbourhood functional diversity, stand heterogeneity and intraspecific and interspecific competition. Dendroecological methods were used to reconstruct radial growth. We recorded all tree species living around each sampled tree and calculated indices of intra‐ and interspecific competition among coexisting trees. Functional diversity around each focal tree was calculated by using the Rao's quadratic entropy.

Silver fir growth decreased significantly in response to the drought in the vast majority of trees, but most of them showed a growth recovery 3 years later. Despite most trees showed negative growth trends following the drought event (70%), those trees growing in more functionally diverse stands were more resilient, recovered more quickly and displayed greater growth and growth trends.

Synthesis. The presented findings support the growing body of evidence that shows a positive impact of diversity on forest function. In addition, we provide a direct linkage between tree growth response to climate at the individual tree scale and a direct quantification of neighbourhood functional diversity and competition. An enhanced functional diversity facilitating a more efficient use of resources at the interspecific level and potentially increasing facilitative interactions contributes to lessening the negative impacts of extreme events as droughts on forest growth.
The Bifurcation of Politics: Two Englands
Authors: Jennings Will , Stoker Gerry 
Published: March 2016

AbstractA dynamic of global economic development means that many countries are experiencing uneven development and their citizens are increasingly split between those who can access high‐skill jobs and those who cannot. As a result some citizens are living in cosmopolitan areas of growth and others in backwater areas of decline. There are emerging out of these processes two versions of England. In cosmopolitan areas we find an England that is global in outlook, liberal and more plural in its sense of identity. In provincial backwaters we find an England that is inward‐looking, relatively illiberal, negative about the EU and immigration, nostalgic and more English in its identity. This bifurcation of England is already having political effects, reflected in the outcome of the 2015 general election. It will further reconfigure politics over the next two decades, creating diverse political citizens and a complex array of challenges and dilemmas for governments, political parties, campaigners and political organisers.
Periodization, Translation, Prescription and the Emergence of Classical French
Authors: Ayres‐Bennett Wendy , Caron Philippe 
Published: March 2016

AbstractIn this article we demonstrate how fine‐grained analysis of salient features of linguistic change over a relatively short, but significant period can help refine our notions of periodization. As our case study, we consider whether it is appropriate to distinguish a period called français préclassique (‘Pre‐Classical French’), and if so, what its temporal limits are. As our contemporary informants we take, on the one hand, the comments of writers of remarks on the French language, who were highly conscious of language change, and, on the other, usage in successive French translations of the same Latin source text which can be exploited to track and date the adoption of ‘modern’ linguistic variants. We find atypical patterns of change – and notably changes which move rapidly through Labov's different stages – that contribute to the sense of discontinuity or periodization. However, this sense of ‘rupture’ does not coincide with the chronological boundaries hitherto suggested for français préclassique, thus throwing the validity of this period into question.
Negation in Colonial Valley Zapotec
Authors: Anderson Carolyn Jane , Lillehaugen Brook Danielle 
Published: March 2016

AbstractThis paper presents an overview of negation in Colonial Valley Zapotec (CVZ) based on a corpus of texts written in Valley Zapotec between 1565 and 1808. There are four negative markers in CVZ, two bound (ya=, qui=) and two free (aca, yaca). Standard negation employs a negative word and an optional clitic, =ti. Understanding the syntax of an historical form of Valley Zapotec allows us to make some observations about related forms in modern Valley Zapotec languages, in particular San Lucas Quiaviní Zapotec (SLQZ). For example, the morpheme =ti, which is required in clausal negation in SLQZ, is not obligatory in any negative constructions in CVZ until around 1800. In Vellon 1808, the youngest text in the corpus, we observe =ti required in one type of clausal negation. This allows us to observe details of the development of the modern Valley Zapotec negation system, including the fact that the remaining changes leading to obligatory =ti in clausal negation in SLQZ must have occurred within the last 200 years.
Tax Policies, Regional Trade Agreements and Foreign Direct Investment: A Welfare Analysis
Authors: Braymen Charles , Chang Yang‐Ming , Luo Zijun 
Published: March 2016

AbstractIn this paper, we develop a partial equilibrium three‐country model to examine the relationship between regional trade agreements (RTAs) and foreign direct investment (FDI) in an environment with double taxation. Our analysis shows that FDI is welfare‐improving for at least one or both of the two regional countries if wage asymmetry is significantly large. FDI and an RTA are also welfare‐improving for the high‐wage country and the region if the wage differential is not small. We also examine the role of repatriation taxes in affecting the determination of firm location under an RTA. Our results suggest that the signing of an RTA may induce relocation from the high‐wage country to the low‐wage country unless an increase in the repatriation tax rate also occurs.
What Drives Urban Consumption in Mainland China? The Role of Property Price Dynamics
Authors: Chen Yu‐Fu , Funke Michael , Mehrotra Aaron 
Published: March 2016

AbstractThis paper adds to the literature on wealth effects on consumption by disentangling house price effects on consumption for mainland China. In a stochastic modelling framework, the riskiness, rate of increase and persistence of house price movements have different implications for the consumption/housing ratio. We exploit the geographical variation in property prices by using a quarterly city‐level panel data set for the period 1998Q1–2009Q4 and rely on a panel error correction model. Overall, the results suggest a significant long‐run impact of property prices on consumption. They also broadly confirm the predictions from the theoretical model.
Influence of guar gum addition on physicochemical, microbial, rheological and sensory properties of stirred yoghurt
Authors: Lee Youngseung , Chang Yoon Hyuk 
Published: March 2016

This study investigated the effects of adding guar gum (0, 0.6 and 0.8 g/100 mL) on the physicochemical, microbial, rheological and sensory properties of stirred yoghurt. Incorporation of guar gum into the yoghurt significantly affected the pH and colour, but did not significantly influence the lactic acid bacteria counts. The magnitudes of apparent viscosity (ηa,100), consistency index (K), yield stress (σoc), storage modulus (G′) and loss modulus (G″) for yoghurt samples containing guar gum (0.6–0.8 g/100 mL) were significantly greater than those for the control (without guar gum), indicating that guar gum can improve the steady and dynamic shear rheological properties of yoghurt.
Screening Mammography for Free: Impact of Eliminating Cost Sharing on Cancer Screening Rates
Authors: Jena Anupam B. , Huang Jie , Fireman Bruce , Fung Vicki , Gazelle Scott , Landrum Mary Beth , Chernew Michael , Newhouse Joseph P. , Hsu John 
Published: March 2016

ObjectivesTo study the impact of eliminating cost sharing for screening mammography on mammography rates in a large Medicare Advantage (MA) health plan which in 2010 eliminated cost sharing in anticipation of the Affordable Care Act mandate.Study SettingLarge MA health maintenance organization offering individual‐subscriber MA insurance and employer‐supplemented group MA insurance.Study DesignWe investigated the impact on breast cancer screening of a policy that eliminated a $20 copayment for screening mammography in 2010 among 53,188 women continuously enrolled from 2007 to 2012 in an individual‐subscriber MA plan, compared with 42,473 women with employer‐supplemented group MA insurance in the same health maintenance organization who had full screening coverage during this period. We used differences‐in‐differences analysis to study the impact of cost‐sharing elimination on mammography rates.Principal FindingsAnnual screening rates declined over time for both groups, with similar trends pre‐2010 and a slower decline after 2010 among women whose copayments were eliminated. Among women aged 65–74 years in the individual‐subscriber MA plan, 44.9 percent received screening in 2009 compared with 40.9 percent in 2012, while 49.5 percent of women in the employer‐supplemented MA plan received screening in 2009 compared with 44.1 percent in 2012, that is, a difference‐in‐difference effect of 1.4 percentage points less decline in screening among women experiencing the cost‐sharing elimination. Effects were concentrated among women without recent screening. There were no differences by neighborhood socioeconomic status or race/ethnicity.ConclusionsEliminating cost sharing for screening mammography was associated with modesty lower decline in screening rates among women with previously low screening adherence.
Do Opinions on Financial Misstatement Firms Affect Analysts’ Reputation with Investors? Evidence from Reputational Spillovers
Authors: LEE LIAN FEN , LO ALVIS K. 
Published: March 2016

ABSTRACTWe examine whether opinions on firms subsequently revealed to have misstated earnings affect analysts’ reputation with investors. We find that positive opinions by bullish analysts hurt their reputation, leading investors to react less to their research on non‐misstatement firms after the misstatement revelation (i.e., negative spillovers). We also find that bearish analysts issuing more negative opinions gain reputation and experience positive spillovers. Finally, for analysts who dropped coverage of the misstatement firm before the misstatement revelation, we find no spillovers, which suggests that analysts experience limited reputational gains when they did not issue a public negative opinion.
The Quality Changes of Postharvest Mulberry Fruit Treated by Chitosan‐g‐Caffeic Acid during Cold Storage
Authors: Yang Caifeng , Han Beibei , Zheng Yu , Liu Lili , Li Changlong , Sheng Sheng , Zhang Jian , Wang Jun , Wu Fuan 
Published: March 2016

AbstractThis study aimed to characterize the effects of chitosan‐g‐caffeic acid (CTS‐g‐CA) on improving the quality and extending the shelf life of postharvest mulberry fruit during storage at 4 °C for 18 d. CTS‐g‐CA was enzymatically synthesized using laccase from Pleurotus ostreatus as a catalyst. The synergistic effects of CTS‐g‐CA treatment on mulberry fruit were evaluated using a co‐toxicity factor (cf). The results showed that the rotting rate of CTS‐g‐CA‐treated fruit was 37.67% (compared with that of the control at 97.67%) on day 18. The weight loss and malondialdehyde (MDA) contents of the CTS‐g‐CA‐treated mulberry fruit were significantly lower (P < 0.05) than those of the control, CA, CTS, and CA+CTS treatments. Moreover, the DPPH and ABTS radical scavenging activities of the CTS‐g‐CA treatment were both higher than those of the control. Furthermore, the CTS‐g‐CA treatment also maintained higher levels of main active substances, such as anthocyanins, ascorbic acid, polyphenols and flavones, in mulberry fruit than the other treatments. Therefore, CTS‐g‐CA could be used to improve the quality and extend the shelf life of postharvest mulberry fruit during cold storage.
Effect of Aqueous Extract of the Seaweed Gracilaria domingensis on the Physicochemical, Microbiological, and Textural Features of Fermented Milks
Authors: Tavares Estevam Adriana Carneiro , Alonso Buriti Flávia Carolina , de Oliveira Tiago Almeida , Pereira Elainy Virginia dos Santos , Florentino Eliane Rolim , Porto Ana Lúcia Figueiredo 
Published: March 2016

AbstractThe effects of the Gracilaria domingensis seaweed aqueous extract in comparison with gelatin on the physicochemical, microbial, and textural characteristics of fermented milks processed with the mixed culture SAB 440 A, composed of Streptococcus thermophilus, Lactobacillus acidophilus, and Bifidobacterium animalis ssp. lactis, were investigated. The addition of G. domingensis aqueous extract did not affect pH, titratable acidity, and microbial viability of fermented milks when compared with the control (with no texture modifier) and the products with added gelatin. Fermented milk with added the seaweed aqueous extract showed firmness, consistency, cohesiveness, and viscosity index at least 10% higher than those observed for the control product (P < 0.05). At 4 h of fermentation, the fermented milks with only G. domingensis extract showed a texture comparable to that observed for products containing only gelatin. At 5 h of fermentation, firmness and consistency increased significantly (P < 0.05) in products with only seaweed extract added, a behavior not observed in products with the full amount of gelatin, probably due to the differences between the interactions of these ingredients with casein during the development of the gel network throughout the acidification of milk. The G. domingensis aqueous extract appears as a promising gelatin alternative to be used as texture modifier in fermented milks and related dairy products.