Dynamic Environmental Research Articles

Dynamic Environmental Photosynthetic Imaging Reveals Emergent Phenotypes

Understanding and improving the productivity and robustness of plant photosynthesis requires high-throughput phenotyping under environmental conditions that are relevant to the field. Here we demonstrate the dynamic environmental photosynthesis imager (DEPI), an experimental platform for integrated, continuous, and high-throughput measurements of photosynthetic parameters during plant growth under reproducible yet dynamic environmental conditions. Using parallel imagers obviates the need to move plants or sensors, reducing artifacts and allowing simultaneous measurement on large numbers of plants. As a result, DEPI can reveal phenotypes that are not evident under standard laboratory conditions but emerge under progressively more dynamic illumination. We show examples in mutants of Arabidopsis of such "emergent phenotypes" that are highly transient and heterogeneous, appearing in different leaves under different conditions and depending in complex ways on both environmental conditions and plant developmental age. These emergent phenotypes appear to be caused by a range of phenomena, suggesting that such previously unseen processes are critical for plant responses to dynamic environments.

Vegetation mapping in the St Lucia estuary using very high-resolution multispectral imagery and LiDAR

This paper examines the value of very high-resolution multispectral satellite imagery and LiDAR-derived digital elevation information for classifying estuarine vegetation types. Satellite images used are from the WorldView-2, RapidEye, and SPOT-6 sensors in 2m and 5m resolution, respectively, acquired between 2010 and 2014. Ground truthing reference is a GIS-derived vegetation map based on field data from 2008. Supervised maximum likelihood classification produced satisfactory overall accuracies between 64.3% and 77.9% for the SPOT-6 and the WorldView-2 image, respectively, while the RapidEye-based classifications produced overall accuracies between 55.0% and 66.8%. The reasons for the misclassifications are mainly based on the highly dynamic environmental conditions causing discrepancies between the field data and satellite acquisition dates rather than technical issues. Dynamics in water levels and salinity caused rapid change in vegetation communities. Further, weather impacts such as floods and wind events caused water turbidity and led to bias in the reflective properties of the satellite images and thus misclassifications. These results show, however, that the spatial and spectral resolution of modern very high-resolution imagery is sufficient to satisfactory map estuarine vegetation and to monitor small-scale change. They emphasise, however, the importance of synchronisation of ground truthing data with actual image acquisition dates in these highly dynamic environments in order to achieve high classification accuracies. The results also highlight the importance of ancillary data for accurate interpretation of observed classification discrepancies and vegetation dynamics.

PENGARUH PROMOSI DAN KINERJA PELAYANAN TERHADAP LOYALITAS NASABAH DENGAN KEPUASAN NASABAH SEBAGAI PEMODERASI: STUDI PADA BANK BUMN DI DIY

Environmental dynamics shown by the uncertain situation faced by the company. Uncertain situationdue to a catastrophic event is one of the factors that need to be anticipated by the company. This studyaimed to analyze the effect of dynamic marketing capabilities to the performance of the creativeindustries and the dynamic moderating influence of the environment on their relationship in situationsof disaster that struck the Yogyakarta area.This study was conducted with 103 respondents.Respondents include business entrepreneurs of creative industries in Yogyakarta, especially in smalland medium business group. Hypothesis testing is done by regression analysis and regressionanalysis moderation. The results showed only two of the four hypotheses were supported, wherestrategic flexibility significantly affect firm performance, while dynamic environment do not moderatethe relationship between the two.Keywords: Dynamic Marketing Capability, Market Orientation, Strategic Flexibility,Environmental Dynamism, and Firm Performance

Dynamic Environment Coupling Induced Synchronized States in Coupled Time-Delayed Electronic Circuits

We experimentally demonstrate the effect of dynamic environment coupling in a system of coupled piecewise linear time-delay electronic circuits with mutual and subsystem coupling configurations. Time-delay systems are essentially infinite-dimensional systems with complex phase-space properties. Dynamic environmental coupling with mutual coupling configuration has been recently theoretically shown to induce complete (CS) and inverse synchronizations (IS) [Resmi et al., 2010] in low-dimensional dynamical systems described by ordinary differential equations (ODEs), for which no experimental confirmation exists. In this paper, we investigate the effect of dynamic environment for the first time in mutual as well as subsystem coupling configurations in coupled time-delay differential equations theoretically and experimentally. Depending upon the coupling strength and the nature of feedback, we observe a transition from asynchronization to CS via phase synchronization and from asynchronization to IS via inverse-phase synchronization in both coupling configurations. The results are corroborated by snapshots of the time evolution, phase projection plots and localized sets as observed from the oscilloscope. Further, the synchronization is also confirmed numerically from the largest Lyapunov exponents, correlation of probability of recurrence and correlation coefficient of the coupled time-delay system. We also present a linear stability analysis and obtain conditions for different synchronized states.

Adaptive and online data anomaly detection for wireless sensor systems

Wireless sensor networks (WSNs) are increasingly used as platforms for collecting data from unattended environments and monitoring important events in phenomena. However, sensor data is affected by anomalies that occur due to various reasons, such as, node software or hardware failures, reading errors, unusual events, and malicious attacks. Therefore, effective, efficient, and real time detection of anomalous measurement is required to guarantee the quality of data collected by these networks. In this paper, two efficient and effective anomaly detection models PCCAD and APCCAD are proposed for static and dynamic environments, respectively. Both models utilize the One-Class Principal Component Classifier (OCPCC) to measure the dissimilarity between sensor measurements in the feature space. The proposed APCCAD model incorporates an incremental learning method that is able to track the dynamic normal changes of data streams in the monitored environment. The efficiency and effectiveness of the proposed models are demonstrated using real life datasets collected by real sensor network projects. Experimental results show that the proposed models have advantages over existing models in terms of efficient utilization of sensor limited resources. The results further reveal that the proposed models achieve better detection effectiveness in terms of high detection accuracy with low false alarms especially for dynamic environmental data streams compared to some existing models.

Performance Analysis of Non-Linear Equalizer in MIMO System for Vehicular Channel

All wireless technologies face the challenges of multipath signal fading, attenuation delay and phase delay which led to the interference between users and there is the possibility of limited spectrum. Linear and Non-Linear receiver is used to combat the effect of multipath signal fading and delay. The linear receiver gives best result in case of static environment but in case of dynamic environmental condition it fails to give better results and hence in order to improve the system performance non-linear receiver is used in dynamic environment condition. As a dynamic channel, Vehicular Channel model is considered because there is growing interest in vehicular networking and it is also a challenging channel model because of the complexity of the environment, and rapid variation in channel conditions. This paper studies the comparison between Zero Forcing (ZF) and Minimum Mean Square Error (MMSE) receiver in the Vehicular Channel. A comparative study between linear equalizer and non- linear equalizer in the Vehicular Channel is done and analyze the effect of the varying modulation and antenna configuration on the performance.

An adaptive and efficient dimension reduction model for multivariate wireless sensor networks applications

Wireless sensor networks (WSNs) applications are growing rapidly in various fields such as environmental monitoring, health care management, and industry control. However, WSN's are characterized by constrained resources especially; energy which shortens their lifespan. One of the most important factors that cause a rapid drain of energy is radio communication of multivariate data between nodes and base station. Besides, the dynamic changes of environmental variables pose a need for an adaptive solution that cope with these changes over the time. In this paper, a new adaptive and efficient dimension reduction model (APCADR) is proposed for hierarchical sensor networks based on the candid covariance-free incremental PCA (CCIPCA). The performance of the model is evaluated using three real sensor networks datasets collected at Intel Berkeley Research Lab (IBRL), Great St. Bernard (GSB) area, and Lausanne Urban Canopy Experiments (LUCE). Experimental results show 33.33% and 50% reduction of multivariate data in dynamic and static environments, respectively. Results also show that 97–99% of original data is successfully approximated at cluster heads in both environment types. A comparison with the multivariate linear regression model (MLR) and simple linear regression model (SLR) shows the advantage of the proposed model in terms of efficiency, approximation accuracy, and adaptability with dynamic environmental changes.

The Transient Characteristerics Evaluation of Dynamic Environmental Test of Satellite

The dynamic environmental test of spacecraft products plays an important role to guarantee the reliability. Dynamic environment of spacecraft mainly generated in the launch phase, has short effect time, so the transient characteristics of spacecraft products are very important. In this paper, the dynamic test purposes of different developed stages (mainly include structural model phase and flight model phase)are sorted out, evaluation contents of spacecraft products are summed up relative to the dynamic test purposes and evaluation criteria are setup corresponding the evaluation contents. Though it, the transient characteristics of spacecraft products are evaluated which provides a reference for judging the reliability of spacecraft products.

The Passive Yet Successful Way of Planktonic Life: Genomic and Experimental Analysis of the Ecology of a Free-Living Polynucleobacter Population

BackgroundThe bacterial taxon Polynucleobacter necessarius subspecies asymbioticus represents a group of planktonic freshwater bacteria with cosmopolitan and ubiquitous distribution in standing freshwater habitats. These bacteria comprise <1% to 70% (on average about 20%) of total bacterioplankton cells in various freshwater habitats. The ubiquity of this taxon was recently explained by intra-taxon ecological diversification, i.e. specialization of lineages to specific environmental conditions; however, details on specific adaptations are not known. Here we investigated by means of genomic and experimental analyses the ecological adaptation of a persistent population dwelling in a small acidic pond.FindingsThe investigated population (F10 lineage) contributed on average 11% to total bacterioplankton in the pond during the vegetation periods (ice-free period, usually May to November). Only a low degree of genetic diversification of the population could be revealed. These bacteria are characterized by a small genome size (2.1 Mb), a relatively small number of genes involved in transduction of environmental signals, and the lack of motility and quorum sensing. Experiments indicated that these bacteria live as chemoorganotrophs by mainly utilizing low-molecular-weight substrates derived from photooxidation of humic substances.ConclusionsEvolutionary genome streamlining resulted in a highly passive lifestyle so far only known among free-living bacteria from pelagic marine taxa dwelling in environmentally stable nutrient-poor off-shore systems. Surprisingly, such a lifestyle is also successful in a highly dynamic and nutrient-richer environment such as the water column of the investigated pond, which was undergoing complete mixis and pronounced stratification in diurnal cycles. Obviously, metabolic and ecological versatility is not a prerequisite for long-lasting establishment of abundant bacterial populations under highly dynamic environmental conditions. Caution should be exercised when generalizing the obtained insights into the ecology and adaptation of the investigated lineage to other Polynucleobacter lineages.

Key techniques for predicting the uncertain trajectories of moving objects with dynamic environment awareness

Emerging technologies of wireless and mobile communication enable people to accumulate a large volume of time-stamped locations, which appear in the form of a continuous moving object trajectory. How to accurately predict the uncertain mobility of objects becomes an important and challenging problem. Existing algorithms for trajectory prediction in moving objects databases mainly focus on identifying frequent trajectory patterns, and do not take account of the effect of essential dynamic environmental factors. In this study, a general schema for predicting uncertain trajectories of moving objects with dynamic environment awareness is presented, and the key techniques in trajectory prediction are addressed in detail. In order to accurately predict the trajectories, a trajectory prediction algorithm based on continuous time Bayesian networks (CTBNs) is improved and applied, which takes dynamic environmental factors into full consideration. Experiments conducted on synthetic trajectory data verify the effectiveness of the improved algorithm, which also guarantees the time performance as well.

Market Dynamics, Dynamic Resource Management and Environmental Policy in the Context of (Strong) Sustainability

In this paper, we investigate the relationship between market dynamics, dynamic resource management and environmental policy. In contrast to static market entry games, this paper draws attention to the effects of market dynamics on resource dynamics et vice versa, because (1) we show that feedback processes are necessary for obtaining a better understanding of what drives the dynamics between the evolution of common-pool resources and the number of harvesters and more importantly, (2) this analysis provides an environment discussing sustainability in an appropriate inasmuch dynamic way. The paper makes following major points: (1) Interpreting the monopoly-scenario as a non-cooperative solution and the firm coexistence solution as a cooperative solution, it is shown that the coexistence solution of this model implies a degenerate saddle-node equilibrium. (2) An increasing number of harvesters does not necessarily imply a lower stock of the common-pool resource in the long run. (3) The paper introduces a way establishing an output-sharing solution by implementing an output tax, which turns out to be a pure effort tax in the long run. (4) Strong resource sustainability is not possible, given cost reducing technological progress is relevant and policy interventions ceased. With respect to environmental policy, we can conclude that a tax scheme is not a substitute to a partnership solution dealing with the common-pool problem, but is treated as an instrument establishing such a solution in the sense of a policy mix approach.

Stochastic Cellular Automata in Dynamic Environmental Modeling: Practical Applications

This article presents the key aspects of an intuitive programming approach based on a Cellular automata technique providing an effective, easy to understand tool to describe some real processes. Although for many years most physical effects have been described by the language of differential equations, it may be beneficial in this era of cheap computing power to deploy a new descriptive apparatus based on very simple programs rather than mathematical equations, which are not always capable of capturing nature's most essential mechanisms, including the randomness in physics. Based on these assumptions, the term 'intuitive programming' is used to refer to a system of simple programs with transparent yet complex behavior. The effectiveness of the proposed methodology is demonstrated in a case study of a deteriorating bridge within a dynamic environment with several approaches to stochastic effects.

Strategic leadership for exploration and exploitation: The moderating role of environmental dynamism

This study advances prior theoretical research by linking transformational and transactional behaviors of strategic leaders to two critical outputs of organizational learning: exploratory and exploitative innovation. Findings indicate that transformational leadership behaviors contribute significantly to adopting generative thinking and pursuing exploratory innovation. Transactional leadership behaviors, on the other hand, facilitate improving and extending existing knowledge and are associated with exploitative innovation. In addition, we argue that environmental dynamism needs to be taken into account to fully understand the effectiveness of strategic leaders. Our study provides new insights that misfits rather than fits between leadership behaviors and innovative outcomes matter in dynamic environments. Hence, we contribute to the debate on the role of strategic leaders in managing exploration and exploitation, not only by examining how specific leadership behaviors impact innovative outcomes, but also by revealing how the impact of leadership is contingent upon dynamic environmental conditions.

Comparison of chondrogenesis in static and dynamic environments using a SFF designed and fabricated PCL-PEO scaffold

A tssue engineering approach combining the scaffold/cell/matrix aspires to be a suitable alternative for current cartilage injury treatment modalities to produce a functional cartilage graft. Scaffolds synthesised from elastomeric materials and fabricated by a rapid prototyping technique were tested and investigated as a potential candidate for cartilage tissue engineering. The purpose of this study is to investigate the influence of scaffold internal architectures, matrix composition and dynamic environmental conditions on the final outcome of the scaffold-cell construct. PCL-PEO scaffolds were fabricated with 0°–90° and 0°–45° lay-down patterns with porosity values of 60% and 71% respectively. They were seeded with 500,000 porcine articular chondrocytes along with two different hydrogels, i.e. alginate and alginate/thrombin, and chondrocyte behaviour was studied. Furthermore, scaffold-cell constructs were cultured dynamically using the spinner flask method for 6 weeks. Porosity and surface-to-volume ratios were different for scaffolds with diverse geometry. The 0°–45° pattern scaffold showed significantly increased cell numbers and extracellular matrix proteins such as collagen-II compared to the 0°–90° scaffolds. The alginate/thrombin matrix encapsulated more chondrocytes compared to the alginate matrix alone. Cells were found to be viable and actively proliferating after 6 weeks of culture, maintaining the rounded chondrocyte phenotype in the matrix. Cell number, metabolic activity and extracellular matrix, such as collagen II, were produced significantly more in the dynamic environment compared to the static environment.

Managing Firm Resources in Dynamic Environments to Create Value: Looking Inside the Black Box

We address current criticisms of the RBV (oversight of dynamism, environmental contingencies, and managers' role) by linking value creation in dynamic environmental contexts to the management of firm resources. Components of the resource management model include structuring the resource portfolio; bundling resources to build capabilities; and leveraging capabilities to provide value to customers, gain a competitive advantage, and create wealth for owners. Propositions linking resource management and value creation are offered to shape future research.

Impact of limited short-term sea scallop fishery on epibenthic community of Georges Bank closed areas

On Georges Bank, 2 areas that had been closed to sea scallop fishing since 1994 were opened for a limited harvest from August 2000 to February 2001. The effects of this limited short-term fishery on the epibenthic community were examined using a 'before/after, control/impact' environ- mental design conducted with video surveys. A centric systematic survey with 1379 stations placed on a 1.57 km grid, with 4 video quadrats collected at each station (3.235 m 2 per quadrat equaling 17789 m 2 total sample area), was completed in 2 control and 2 impact areas before and after the fish- ery. The sea scallops Placopecten magellanicus and starfishes (primarily Asterias vulgaris) comprised more than 84% of the fauna. Changes in the number of taxonomic categories and the density of indi- viduals within each category in the areas impacted by the fishery were similar to changes in the con- trol areas that remained closed to fishing. Further, sediment composition shifted between surveys more than epibenthic faunal composition, suggesting that this community is adapted to a dynamic environment. The limited short-term sea scallop fishery on Georges Bank appeared to alter the epibenthic community less than the natural dynamic environmental conditions.

Plasmid stability and ecological competence in recombinant cultures

The instability of cell cultures containing plasmid vectors is a major problem in the commercial exploitation of molecular cloning techniques. Plasmid stability is influenced by the nature of the host cell, the type of plasmid and/or environmental conditions. Plasmid encoded properties may confer a selective advantage on the host cell but can be an energy drain due to replication and expression. Stability of recombinant cultures ultimately may be determined by the cost to benefit ratio of plasmid carriage. The relative competition between plasmid containing and plasmid-free or indigenous populations can determine the degree of dominance of recombinant cultures. The use of inocula in biotechnological processes in which dynamic environmental conditions dominate may also result in instabilities resulting from the characteristics of the ecosystem. In such dynamic conditions plasmid stability is just one contribution to culture stability. Strategies to enhance plasmid stability, within such environments, based on manipulation of physiological state of host cells, must consider the responsiveness or plasticity of both cells and populations. The robustness of cells or the responses to stresses or transient environmental conditions can influence the levels of instability detected; for example, instability or mutation in the host genome may lead to enhanced plasmid stability. Competition among subpopulations arising from unstable copy number control may determine the levels of recombinant cells in open versus closed fermenter systems. Thus the ecological competence (ability to survive and compete) of recombinant cells in dynamic or transient environments is fundamental to the understanding of the ultimate dominance or survival of such recombinant cultures and may form the basis of a strategy to enhance or control stability either in fermenter systems or dynamic process environments The creation of microniches in time and/or space can enhance plasmid stability. Transient operation based on defined environmental stresses or perturbations in fermenter systems or in heterogeneous or dynamic environments found in gel immobilized cultures have resulted in enhanced stability. Spatial organization resulting from immobilization has the additional advantage of regulated cell protection within defined microenvironments and controlled release, depending on the nature of the gel, from these microenvironments or microcosms. This regulation of ecological competence allied to the advantages of microbial cell growth in gel microenvironments combined with the spatial organization (or juxtapositioning of cells, selective agents, nutrients, protectants, etc.) possible through immobilization technology offers new strategies to enhance plasmid and culture stability.

A Procedure for Comparing Dynamic Test Severities Based on Equipment Response Characteristics

Military specifications contain numerous requirements for qualification of equipment for dynamic environments. Cost and schedule effective application of these specifications require tailoring of these test requirements. This paper presents a technique for tailoring dynamic environment tests based on equipment response characteristics. The dynamic response theory is explained and applied to a procedure for comparing the relative severity of dynamic environmental tests. The procedure is shown using the example of an electronic assembly.

Variable Training for a Novel Instance in a Dynamic Environment

The study used an “open” or dynamic environmental task to determine whether the acquisition of novel responses outside the range of the subjects' past experience would be facilitated by variability of training. This was found to be the case for a coincident-timing task. Subjects with high stimulus variability during training showed improved transfer to a novel task. A generalization gradient was obtained; the further the novel conditions were from the training conditions, the poorer was the transfer. However, generalization decrement was attenuated with variable training.