Cascade Pattern Research Articles

Insights from the Cold Transcriptome and Metabolome of Dendrobium officinale: Global Reprogramming of Metabolic and Gene Regulation Networks during Cold Acclimation.

Plant cold acclimation (CA) is a genetically complex phenomenon involving gene regulation and expression. Little is known about the cascading pattern of gene regulatroy network and the link between genes and metabolites during CA. Dendrobium officinale (DOKM) is an important medicinal and ornamental plant and hypersensitive to low temperature. Here, we used the large scale metabolomic and transcriptomic technologies to reveal the response to CA in DOKM seedlings based on the physiological profile analyses. Lowering temperature from 4 to –2°C resulted in significant increase (P < 0.01) in antioxidant activities and electrolyte leakage (EL) during 24 h. The fitness CA piont of 0°C and control (20°C) during 20 h were firstly obtained according to physiological analyses. Subsequently, massive transcriptome and metabolome reprogramming occurred during CA. The gene to metabolite network demonstrated that the CA associated processes are highly energy demanding through activating hydrolysis of sugars, amino acids catabolism and citrate cycle. The expression levels of 2,767 genes were significantly affected by CA, including 153-fold upregulation of CBF transcription factor, 56-fold upregulation of MAPKKK16 protein kinase. Moreover, the gene interaction and regulation network analysis revealed that the CA as an active process, was regulated at the transcriptional, post-transcriptional, translational and post-translational levels. Our findings highligted a comprehensive regulatory mechanism including cold signal transduction, transcriptional regulation, and gene expression, which contributes a deeper understanding of the highly complex regulatory program during CA in DOKM. Some marker genes identified in DOKM seedlings will allow us to understand the role of each individual during CA by further functional analyses.

Normalized-Mutual-Information-Based Mining Method for Cascading Patterns

A cascading pattern is a sequential pattern characterized by an item following another item in order. Recent research has investigated a challenge of dealing with cascading patterns, namely, the exponential time dependence of database scanning with respect to the number of items involved. We propose a normalized-mutual-information-based mining method for cascading patterns (M3Cap) to address this challenge. M3Cap embeds mutual information to reduce database-scanning time. First, M3Cap calculates the asymmetrical mutual information between items with one database scan and extracts pair-wise related items according to a user-specified information threshold. Second, a one-level cascading pattern is generated by scanning the database once for each pair-wise related item at the quantitative level. Third, a recursive linking–pruning–generating loop generates an (m + 1)-level-candidate cascading pattern from m-dimensional patterns on the basis of antimonotonicity and non-additivity, repeating this step until no further candidate cascading patterns are generated. Fourth, meaningful cascading patterns are generated according to user-specified minimum evaluation indicators. Finally, experiments with remote sensing image datasets covering the Pacific Ocean demonstrate that the computation time of recursive linking and pruning is significantly less than that of database scanning; thus, M3Cap improves performance by reducing database scanning while increasing intensive computing.

The scent of your enemy is my friend? The acquisition of large carnivore scent by a smaller carnivore

Scent marking is critical to intraspecific communication in many mammal species, but little is known regarding its role in communication among different species. We used 4 years of motion-triggered video to document the use of scent marking areas—termed “community scrapes”—by pumas (Puma concolor) ( http://www.momo-p.com/showdetail-e.php?movieid=momo160812pc01a ) and other carnivore species. We found that gray foxes (Urocyon cinereoargenteus) routinely rubbed their cheeks on puma scrapes ( http://www.momo-p.com/showdetail-e.php?movieid=momo160812uc01a ), and tested a series of hypotheses to determine its function. We found that gray foxes selected puma scrapes over other objects, and cheek rubbing by foxes was also correlated with how recently a puma had visited the scrape, suggesting that foxes were intent upon accumulating fresh puma scent. Cheek rubbing by foxes was not correlated with their breeding season or with how recently another fox had visited the site. Finally we found a cascading pattern in the occurrence of pumas, coyotes (Canis latrans) and gray foxes at community scrapes, suggesting that gray foxes may use puma scent to deter predation. This is the first published study to find evidence of a subordinate species using the scent of a dominant species to communicate with heterospecifics. The behavioral cascade we found in scent marking patterns also suggests that scent marking could be a mechanism that impacts the distribution and abundance of species. Additional videos pertaining to this article include http://www.momo-p.com/showdetail-e.php?movieid=momo160812uc02a , and http://www.momo-p.com/showdetail-e.php?movieid=momo160812uc03a .

Breaking out of biogeographical modules: range expansion and taxon cycles in the hyperdiverse ant genus Pheidole.

AimWe sought to reconstruct the biogeographical structure and dynamics of a hyperdiverse ant genus, Pheidole, and to test several predictions of the taxon cycle hypothesis. Using large datasets on Pheidole geographical distributions and phylogeny, we (1) inferred patterns of biogeographical modularity (clusters of areas with similar faunal composition), (2) tested whether species in open habitats are more likely to be expanding their range beyond module boundaries, and (3) tested whether there is a bias of lineage flow from high‐ to low‐diversity areas.LocationThe Old World.MethodsWe compiled and jointly analysed a comprehensive database of Pheidole geographical distributions, the ecological affinities of different species, and a multilocus phylogeny of the Old World radiation. We used network modularity methods to infer biogeographical structure in the genus and comparative methods to evaluate the hypotheses.ResultsThe network analysis identified eight biogeographical modules, and a suite of species with anomalous ranges that are statistically more likely to occur in open habitat, supporting the hypothesis that open habitats promote range expansion. Phylogenetic analysis shows evidence for a cascade pattern of colonization from Asia to New Guinea to the Pacific, but no ‘upstream’ colonization in the reverse direction.Main conclusionsThe distributions of Pheidole lineages in the Old World are highly modular, with modules generally corresponding to biogeographical regions inferred in other groups of organisms. However, some lineages have expanded their ranges across module boundaries, and these species are more likely to be adapted to open habitats rather than interior forest. In addition, there is a cascade pattern of dispersal from higher to lower diversity areas during these range expansions. Our findings are consistent with the taxon cycle hypothesis, although they do not rule out alternative interpretations.

PP06.15 – 2928: Presentation of probable Willis-Ekbom disease/restless legs syndrome (pWED/RLS) in children with cerebral palsy

Objective We investigated the clinical presentation of pWED/RLS in children and adolescents with Cerebral Palsy (CP). Methods 30 children/adolescents (age range 1y11m–16y; 18 males) were assessed clinically in BC Children's Hospital Sleep/Wake-Behaviour Clinic & Lab (in two periods: 16 in P1 (2007–2011), and 14 in P2 (2012–2014). In the second period, we integrated family sleep history and applied the concept of therapeutic emplotment, using narrative schema to analyze bedtime problems, nighttime awakenings, and challenging daytime behaviours; assessment reports were shared with patients for quality control purposes. In addition, 10 patients received home-videosomnography (HVS) (Ipsiroglu et al. SSM Ipsiroglu et al. Frontiers 2015). HVS data included: total sleep period (TSP), total sleep time (TST) awake time (AT), sleep efficiency (SE), restful/restless sleep, in combination with individual characteristic movement patterns, to assess cases of suspected WED. We use descriptive statistics to analyze results. Results (A) Clinical Presentation. P1: pWED/RLS 56%; P2: pWED/RLS 100% (family history of WED/RLS: 100%); all patients presented with major insomnia, 30% with parasomnias, and 90% with signs of sleep disordered breathing. (B) Quantitative HVS data. TSP: mean 8h28min (5h27min–11h49min); AT: 6h16min (2:00am–7:20am); TST: 6h14min (3h14min–9h29min); SE: 77.3% (42–95%); restful sleep: 5h12min (3h16min–9h29min); restless sleep: 2h18min (1h02min–6h18min). Qualitative HVS data confirmed the suspected WED/RLS cases and revealed individual characteristic “cascading movement patterns”. Conclusion Major insomnia, experienced by patients with CP, appears to be due to sleep disturbances caused by sleep disordered breathing and also familial-WED/RLS. Along with familial sleep history, the method of therapeutic emplotment encouraged parents to provide best/worst-case scenario narratives associated with their child's insomnia, to reveal additional diagnostic details. Home-videosomnography recordings supported the clinical diagnosis of pWED/RLS in children/adolescents with CP and revealed child-specific cascading movement patterns most probably triggered by periodic limb movements in sleep.

Socialization processes and pathways to healthy financial development for emerging young adults

Using a two-time longitudinal survey, we studied a cohort of college students (N=1511) to develop a socialization model of the proposed pathways leading to healthy financial development. The participants ranged in age from 18 to 21years at Wave 1 and 20 to 24years at Wave 2. After controlling for gender, ethnicity, SES, and negative financial events, our path analysis revealed a cascading pattern of co-occurring change: positive change in individuals' perceived parental socialization had the strongest associations with positive change in financial attitude, financial controllability, and financial efficacy. In addition, both formal and informal financial education played a significant role. In turn, positive change in attitude had the greatest effect on positive change in behaviors, followed by financial efficacy and financial controllability, respectively. We discuss the process whereby positive financial socialization factors may contribute to positive change in the ways that young people think and behave with respect to managing their finances.

The comparative effects of large carnivores on the acquisition of carrion by scavengers.

Pumas (Puma concolor) and black bears (Ursus americanus) are large carnivores that may influence scavenger population dynamics. We used motion-triggered video cameras deployed at deer carcasses to determine how pumas and black bears affected three aspects of carrion acquisition by scavengers: presence, total feeding time, and mean feeding-bout duration. We found that pumas were unable to limit acquisition of carrion by large carnivores but did limit aspects of carrion acquisition by both birds and mesocarnivores. Through their suppression of mesocarnivores and birds, pumas apparently initiated a cascading pattern and increased carrion acquisition by small carnivores. In contrast, black bears monopolized carrion resources and generally had larger limiting effects on carrion acquisition by all scavengers. Black bears also limited puma feeding behaviors at puma kills, which may require pumas to compensate for energetic losses through increasing their kill rates of ungulates. Our results suggest that pumas provide carrion and selectively influence species acquiring carrion, while black bears limit carrion availability to all other scavengers. These results suggest that the effects of large carnivores on scavengers depend on attributes of both carnivores and scavengers (including size) and that competition for carcasses may result in intraguild predation as well as mesocarnivore release.

Cascading time evolution of dissipative structures leading to unique crystalline textures.

This article reports unique pattern formation processes and mechanisms via crystallization of materials under external flow fields as one of the general problems of open nonequilibrium phenomena in statistical physics. The external fields effectively reduce step-by-step the exceedingly large free energy barriers associated with the reduction of the enormously large entropy necessary for crystallization into unique crystalline textures in the absence of the fields. The cascading reduction of the free energy barrier was discovered to be achieved as a consequence of a cascading evolution of a series of dissipative structures. Moreover, this cascading pattern evolution obeys the Ginzburg-Landau law. It first evolves a series of large-length-scale amorphous precursors driven by liquid-liquid phase separation under a relatively low bulk stress and then small-length-scale structures driven by a large local stress concentrated on the heterogeneous amorphous precursors, eventually leading to the formation of unique crystalline textures which cannot be developed free from the external fields. Here the multi-length-scale heterogeneous structures developed in the amorphous precursors play a dominant role in the triggering of the crystallization in the local regions subjected to a large stress concentration even under a relatively small applied bulk stress.

Diversity of multilayer networks and its impact on collaborating epidemics

Interacting epidemics on diverse multilayer networks are increasingly important in modeling and analyzing the diffusion processes of real complex systems. A viral agent spreading on one layer of a multilayer network can interact with its counterparts by promoting (cooperative interaction), suppressing (competitive interaction), or inducing (collaborating interaction) its diffusion on other layers. Collaborating interaction displays different patterns: (i) random collaboration, where intralayer or interlayer induction has the same probability; (ii) concentrating collaboration, where consecutive intralayer induction is guaranteed with a probability of 1; and (iii) cascading collaboration, where consecutive intralayer induction is banned with a probability of 0. In this paper, we develop a top-bottom framework that uses only two distributions, the overlaid degree distribution and edge-type distribution, to model collaborating epidemics on multilayer networks. We then state the response of three collaborating patterns to structural diversity (evenness and difference of network layers). For viral agents with small transmissibility, we find that random collaboration is more effective in networks with higher diversity (high evenness and difference), while the concentrating pattern is more suitable in uneven networks. Interestingly, the cascading pattern requires a network with moderate difference and high evenness, and the moderately uneven coupling of multiple network layers can effectively increase robustness to resist cascading failure. With large transmissibility, however, we find that all collaborating patterns are more effective in high-diversity networks. Our work provides a systemic analysis of collaborating epidemics on multilayer networks. The results enhance our understanding of biotic and informative diffusion through multiple vectors.

COMPUTER-AIDED DIAGNOSIS OF BRAIN TUMORS USING IMAGE ENHANCEMENT AND FUZZY LOGIC

A robust medical image processing system depends upon a variety of aspects, including a proper image enhancement, and an optimal segmentation. An algorithm was proposed in this paper to facilitate the implementation of these two steps. First a Magnetic Resonance (MR) image is enhanced via spatial domain filtering and its contrast is improved, next, the image is segmented using fuzzy C-mean clustering, then the region of interest which might be the tumor or edema, is detected and delineated. The key advantage of this image processing pipeline is the simultaneous use of features computed from the intensity properties of the image in a cascading pattern which makes the computation self-contained. Performance evaluation of the proposed algorithm was carried out on brain images from different MRI's and the algorithm proved to be successful, comparing it with other dedicated applications.

Consumer Search Pattern and Welfare Analysis in Internet Advertising

I develop and compute a dynamic model of search in internet advertising. Micro-level browsing data from Microsoft’s Bing.com (formerly known as Live.com) is used for structural estimations. The model predicts that users do not click on any ad with weak signals due to accumulating search cost and monotonicity of the value function. Rational search reveals a cascading pattern: the user clicks on a sufficiently high, highest-signal ad first, then moves on to the ad with the next highest conditionally expected probability of match once his assessment on the current ad degrades over time. The user exits when maximum assessment of likelihood of match over all ads is below a threshold value. The paper provides a novel approach to understanding rational herding behavior when product quality is only partially revealed.

Cascaded Multicell Trans-Z-Source Inverters

Inverters with high-output voltage gain usually face the problem of high-input current flowing through their components. The problem might further be exaggerated if the inverters use high-frequency magnetic devices like transformers or coupled inductors. Leakage inductances of these devices must strictly be small to prevent overvoltages caused by switching of their winding currents. To avoid these related problems, cascaded trans-Z-source inverters are proposed. They use multiple magnetic cells in an alternately cascading pattern rather than a single magnetic cell with large turns ratio. Simulation and experimental results have shown that the multicell inverters can produce the same high-voltage gain, while keeping currents and voltages of the components low. The inverters can also step down their output voltages like a traditional voltage-source inverter without compromising waveform quality.

Unique inhibitory cascade pattern of molars in canids contributing to their potential to evolutionary plasticity of diet

Developmental origins that guide the evolution of dental morphology and dental formulae are fundamental subjects in mammalian evolution. In a previous study, a developmental model termed the inhibitory cascade model was established. This model could explain variations in relative molar sizes and loss of the lower third molars, which sometimes reflect diet, in murine rodents and other mammals. Here, I investigated the pattern of relative molar sizes (inhibitory cascade pattern) in canids, a taxon exhibiting a wide range of dietary habits. I found that interspecific variation in canid molars suggests a unique inhibitory cascade pattern that differs from that in murine rodents and other previously reported mammals, and that this variation reflects dietary habits. This unique variability in molars was also observed in individual variation in canid species. According to these observations, canid species have greater variability in the relative sizes of first molars (carnassials), which are functionally important for dietary adaptation in the Carnivora. In conclusion, an inhibitory cascade that differs from that in murine rodents and other mammals may have contributed to diverse dietary patterns and to their parallel evolution in canids.

Lagged relationships among sleep disturbance, fatigue, and depressed mood during chemotherapy.

Recent research suggests that sleep disturbance, fatigue, and depressed mood form a symptom cluster in patients treated with chemotherapy. To date, however, no studies have examined lagged relationships among these symptoms during chemotherapy, a time when symptom variability is high. The aim of the current study was to examine lagged changes among daily symptoms during platinum-based chemotherapy. Participants were 78 women with gynecologic cancer (mean age 63 years, SD = 11; 91% Caucasian, 97% non-Hispanic). Sleep disturbance was assessed via wrist actigraphy, whereas fatigue and depressed mood were assessed via daily diary in the week after participants' first chemotherapy infusion. Latent change score models (LCS) were used to examine lagged relationships between symptom pairs. High levels of sleep disturbance (i.e., minutes awake at night) were associated with earlier subsequent peaks in fatigue, and high levels of fatigue were associated with higher subsequent levels of depressed mood. These findings suggest that sleep disturbance, fatigue, and depressed mood occur in a cascade pattern during chemotherapy, in which increases in sleep disturbance contribute to fatigue, which, in turn, contributes to depressed mood. Interventions targeting symptoms early in the cascade, such as sleep disturbance, may provide benefits across multiple downstream symptoms.

Synthesis of polyaspartic acid/5-aminoorotic acid graft copolymer and evaluation of its scale inhibition and corrosion inhibition performance

Polyaspartic acid/5-aminoorotic acid graft copolymer (PASP/5-AOA) was synthesized by the reaction of maleic anhydride, urea and 5-aminoorotic acid (5-AOA). The graft copolymer (PASP/5-AOA) was characterized by FT-IR and UV–VIS analyses. Its performance was evaluated by static scale inhibition method and dynamic corrosion testing. The results showed that PASP/5-AOA possessed super scale inhibition property against CaCO3 and Ca3(PO4)2 as well as good corrosion inhibition property. Inhibition efficiency of PASP/5-AOA was close to 100% against CaCO3 when the dosage was 1mg/L in the simulation experiment. Corrosion inhibition efficiency was close to 60% and scale inhibition efficiency was close to 100% against Ca3(PO4)2 when the dosage was 12mg/L in the simulation experiment. When PASP/5-AOA was added to the solution, CaCO3 and Ca3(PO4)2 deposits show flower and cascade patterns with floppy accumulation by scanning electron microscopy (SEM).

Trophic and functional cascades in tropical versus temperate aquatic microcosms

Inverse trophic cascades are a well explored and common consequence of the local depletion or extinction of top predators in natural ecosystems. Despite a large body of research, the cascading effects of predator removal on ecosystem functions are not as well understood. Developing microcosm experiments, we explored food web changes in trophic structure and ecosystem functioning following biomass removal of top predators in representative temperate and tropical rock pool communities that contained similar assemblages of zooplankton and benthic invertebrates. We observed changes in species abundances following predator removal in both temperate and tropical communities, in line with expected inverse effects of a trophic cascade, where predation release benefits the predator’s preys and competitors and impacts the preys of the latter. We also observed several changes at the community and ecosystem levels including a decrease in total abundance and mean trophic level of the community, and changes in chlorophyll-a and total dissolved particles. Our results also showed an increase in variability of both community and ecosystem processes following the removal of predators. These results illustrate how predator removal can lead to inverse trophic cascades both in structural and functioning properties, and can increase variability of ecosystem processes. Although observed patterns were consistent between tropical and temperate communities following an inverse cascade pattern, changes were more pronounced in the temperate community. Therefore, aquatic food webs may have inherent traits that condition ecosystem responses to changes in top-down trophic control and render some aquatic ecosystems especially sensitive to the removals of top predators.

Biodegradation of 4-hydroxybenzoic acid by Phomopsis liquidambari

Phenolic acid allelochemicals released by decomposing foliage can have negative impacts on growth of plants and microbes in soil. However, these chemicals can potentially be degraded by broad-spectrum endophytic fungi such as, Phomopsis liquidambari (strain B3), which is capable of growing on phenolic 4-hydroxybenzoic acid (4-HBA) as the sole carbon and energy source. In this study, the optimum concentration of 4-HBA supplied in culture as the carbon source was determined to be 600 mg L −1, with maximum biomass of fungal growth and, 94% and 99% degraded by P. liquidambari in liquid culture and soil conditions, respectively, within 48 h. The fungal metabolic pathway of 4-HBA was investigated using high performance liquid chromatography–mass spectrometry (HPLC–MS) and gas chromatography–mass spectrometry (GC–MS). The results showed that 4-HBA was first hydroxylated to 3,4-dihydroxybenzoic acid, converted to catechol and then oxidated to cis, cis-muconic acid in the tricarboxylic acid (TCA) cycle. The benzene ring was opened through ortho catechol cleavage. During the course of fungal incubation, activities of three main 4-HBA degradation pathway enzymes exhibited a continuous cascading pattern of induction. 4-HBA hydroxylase showed the highest activity after 8 h of incubation, with 3,4-dihydroxybenzoic acid decarboxylase reaching a peak at 24 h and catechol 1,2-dioxygenase peaking at 32 h, which corresponded with changes in corresponding substrate concentrations. These results indicated the bioremediation potential of this endophytic fungus to degrade accumulated phenolic acid allelochemicals in soil to alleviate the effects of their ecological suppression.

Fishing Indirectly Structures Macroalgal Assemblages by Altering Herbivore Behavior

Fishing has clear direct effects on harvested species, but its cascading, indirect effects are less well understood. Fishing disproportionately removes larger, predatory fishes from marine food webs. Most studies of the consequent indirect effects focus on density-mediated interactions where predator removal alternately drives increases and decreases in abundances of successively lower trophic-level species. While prey may increase in number with fewer predators, they may also alter their behavior. When such behavioral responses impact the food resources of prey species, behaviorally mediated trophic cascades can dramatically shape landscapes. It remains unclear whether this pathway of change is typically triggered by ocean fishing. By coupling a simple foraging model with empirical observations from coral reefs, we provide a mechanistic basis for understanding and predicting how predator harvest can alter the landscape of risk for herbivores and consequently drive dramatic changes in primary producer distributions. These results broaden trophic cascade predictions for fisheries to include behavioral changes. They also provide a framework for detecting the presence and magnitude of behaviorally mediated cascades. This knowledge will help to reconcile the disparity between expected and observed patterns of fishing-induced cascades in the sea.

Continuity and cascade in offspring of bipolar parents: A longitudinal study of externalizing, internalizing, and thought problems

There is growing evidence that many offspring of bipolar parents will develop moderate to severe forms of psychopathology during childhood and adolescence. The purpose of this study was to apply growth curve models to evaluate developmental progression with regard to continuity and cascades representative within the context of a family risk study of bipolar disorder (BD). Repeated assessments of externalizing, internalizing, and thought problems, spanning more than a decade, were examined in a total of 94 offspring of parents with BD (O-BD), major depressive disorder (O-UNI), or no significant psychiatric or medical problems (O-WELL). Continuity was defined by the growth curve of the O-WELL group who exhibited low levels of problems from early childhood through late adolescence. Discontinuity, as evidenced by greater complexity of growth curves relative to the O-WELL group, was exhibited in the at- risk offspring groups for internalizing problems. Different patterns of developmental cascades were supported for the at-risk group with O-UNI showing a robust cascade from self-regulatory deficits (externalizing problems) to internalizing problems. There was also support for a cascade from self-regulatory deficits to thought problems across the entire group (with some support that this pattern was accounted for primarily by O-BD). This study not only serves to advance our understanding of the risks associated with a family history of BD, but also provides a novel approach to examining developmental cascades.

Cumulus cell gene expression following the LH surge in bovine preovulatory follicles: potential early markers of oocyte competence

Cumulus cells (CCs) are essential for oocytes to reach full development competency and become fertilized. Many major functional properties of CCs are triggered by gonadotropins and governed by the oocyte. Consequently, cumulus may reflect oocyte quality and is often used for oocyte selection. The most visible function of CCs is their ability for rapid extracellular matrix expansion after the LH surge. Although unexplained, LH induces the final maturation and improves oocyte quality. To study the LH signaling and gene expression cascade patterns close to the germinal vesicle breakdown, bovine CCs collected at 2 h before and 6 h after the LH surge were hybridized to a custom-made microarray to better understand the LH genomic action and find differentially expressed genes associated with the LH-induced oocyte final maturation. Functional genomic analysis of the 141 overexpressed and 161 underexpressed clones was performed according to their molecular functions, gene networks, and cell compartments. Following real-time PCR validation of our gene lists, some interesting pathways associated with the LH genomic action on CCs and their possible roles in oocyte final maturation, ovulation, and fertilization are discussed. A list of early potential markers of oocyte competency in vivo and in vitro is thereafter suggested. These early biomarkers are a preamble to understand the LH molecular pathways that trigger the final oocyte competence acquisition process in bovine.