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1
ORTIZ, A. R., H. T. BANKS, C. CASTILLO-CHAVEZ, G. CHOWELL, and X. WANG. "A DETERMINISTIC METHODOLOGY FOR ESTIMATION OF PARAMETERS IN DYNAMIC MARKOV CHAIN MODELS." Journal of Biological Systems 19, no. 01 (2011): 71–100. http://dx.doi.org/10.1142/s0218339011003798.
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A method for estimating parameters in dynamic stochastic (Markov Chain) models based on Kurtz's limit theory coupled with inverse problem methods developed for deterministic dynamical systems is proposed and illustrated in the context of disease dynamics. This methodology relies on finding an approximate large-population behavior of an appropriate scaled stochastic system. The approach leads to a deterministic approximation obtained as solutions of rate equations (ordinary differential equations) in terms of the large sample size average over sample paths or trajectories (limits of pure jump Markov processes). Using the resulting deterministic model, we select parameter subset combinations that can be estimated using an ordinary-least-squares (OLS) or generalized-least-squares (GLS) inverse problem formulation with a given data set. The selection is based on two criteria of the sensitivity matrix: the degree of sensitivity measured in the form of its condition number and the degree of uncertainty measured in the form of its parameter selection score. We illustrate the ideas with a stochastic model for the transmission of vancomycin-resistant enterococcus (VRE) in hospitals and VRE surveillance data from an oncology unit.
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Hussain, Sarfraz, Abdul Quddus, Pham Phat Tien, Muhammad Rafiq, and Drahomíra Pavelková. "The moderating role of firm size and interest rate in capital structure of the firms: selected sample from sugar sector of Pakistan." Investment Management and Financial Innovations 17, no. 4 (2020): 341–55. http://dx.doi.org/10.21511/imfi.17(4).2020.29.
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The selection of financing is a top priority for businesses, particularly in short- and long-term investment decisions. Mixing debt and equity leads to decisions on the financial structure for businesses. This research analyzes the moderate position of company size and the interest rate in the capital structure over six years (2013–2018) for 29 listed Pakistani enterprises operating in the sugar market. This research employed static panel analysis and dynamic panel analysis on linear and nonlinear regression methods. The capital structure included debt to capital ratio, non-current liabilities, plus current liabilities to capital as a dependent variable. Independent variables were profitability, firm size, tangibility, Non-Debt Tax Shield, liquidity, and macroeconomic variables were exchange rates and interest rates. The investigation reported that profitability, firm size, and Non-Debt Tax Shield were significant and negative, while tangibility and interest rates significantly and positively affected debt to capital ratio. This means the sugar sector has greater financial leverage to manage the funding obligations for the better performance of firms. Therefore, the outcomes revealed that the moderators have an important influence on capital structure.
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Shan, Gui Jun. "A Dynamic Neighborhood Selection Approach for Locally Linear Embedding." Advanced Materials Research 1033-1034 (October 2014): 1369–72. http://dx.doi.org/10.4028/www.scientific.net/amr.1033-1034.1369.
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Locally linear embedding is based on the assumption that the whole data manifolds are evenly distributed so that they determine the neighborhood for all points with the same neighborhood size. Accordingly, they fail to nicely deal with most real problems that are unevenly distributed. This paper presents a new approach that takes the general conceptual framework of Hessian locally linear embedding so as to guarantee its correctness in the setting of local isometry to an open connected subset but dynamically determines the local neighborhood size for each point. This approach estimates the approximate geodesic distance between any two points by the shortest path in the local neighborhood graph, and then determines the neighborhood size for each point by using the relationship between its local estimated geodesic distance matrix and local Euclidean distance matrix. This approach has clear geometry intuition as well as the better performance and stability to deal with the sparsely sampled or noise contaminated data sets that are often unevenly distributed. The conducted experiments on benchmark data sets validate the proposed approach.
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Orlova, Vera, Vyacheslav Goiko, Yulia Alexandrova, and Evgeny Petrov. "Potential of the dynamic approach to data analysis." E3S Web of Conferences 258 (2021): 07012. http://dx.doi.org/10.1051/e3sconf/202125807012.
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Explores the potential of a dynamic data analysis approach to study user behavior in social networks. Currently, information appears on social networks that allows differentiating user groups by their activity within the technical capabilities of a particular social network. The description of the information field of Tomsk is presented, a brief analysis is given. A dynamic approach to the study of user behavior, the structure of nodes and connections of social networks makes it possible to identify the rate of growth or decrease in the size of the network, the redistribution of connections between groups. There are four main stages in the analysis of social networks: 1) data collection; 2) selection of data for analysis; 3) selection and application of the analysis method; and 4) drawing conclusions. To obtain a complete picture of the information field of the Tomsk region, posts for 2019 were unloaded from all regional communities. All posts were classified based on training sample and specialized machine learning algorithm.
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Thomas, Zoë A., Chris S. M. Turney, Alan Hogg, Alan N. Williams, and Chris J. Fogwill. "Investigating Subantarctic 14C Ages of Different Peat Components: Site and Sample Selection for Developing Robust Age Models in Dynamic Landscapes." Radiocarbon 61, no. 4 (2019): 1009–27. http://dx.doi.org/10.1017/rdc.2019.54.
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ABSTRACTPrecise radiocarbon (14C) dating of sedimentary sequences is important for developing robust chronologies of environmental change, but sampling of suitable components can be challenging in highly dynamic landscapes. Here we investigate radiocarbon determinations of different peat size fractions from six peat sites, representing a range of geomorphological contexts on the South Atlantic subantarctic islands of the Falklands and South Georgia. To investigate the most suitable fraction for dating, 112 measurements were obtained from three components within selected horizons: a fine fraction <0.2 mm, a coarse fraction >0.2 mm, and bulk material. We find site selection is critical, with locations surrounded by high-ground and/or relatively slowly accumulating sites more susceptible to the translocation of older carbon. Importantly, in locations with reduced potential for redeposition of material, our results show that there is no significant or systematic difference between ages derived from bulk material, fine or coarse (plant macrofossil) material, providing confidence in the resulting age model. Crucially, in areas comprising complex terrain with extreme relief, we recommend dating macrofossils or bulk carbon rather than a fine fraction, or employing comprehensive dating of multiple sedimentary fractions to determine the most reliable fraction(s) for developing a robust chronological framework.
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Mao, W., M. Tian, and G. Yan. "Research of load identification based on multiple-input multiple-output SVM model selection." Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science 226, no. 5 (2011): 1395–409. http://dx.doi.org/10.1177/0954406211423454.
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In this article, the problem of multiple-input multiple-output (MIMO) load identification is addressed. First, load identification is proved in dynamic theory as non-linear MIMO black-box modelling process. Second, considering the effect of hyper-parameters in small-size sample problem, a new MIMO Support Vector Machine (SVM) model selection method based on multi-objective particle swarm optimization is proposed in order to improve the identification's performance. The proposed method treats the model selection of MIMO SVM as a multi-objective optimization problem, and leave-one-out generalization errors of all output models are minimized simultaneously. Once the Pareto-optimal solutions are found, the SVM model with the best generalization ability is determined. The proposed method is evaluated in the experiment of dynamic load identification on cylinder stochastic vibration system, demonstrating its benefits in comparison to the existing model selection methods in terms of identification accuracy and numerical stability, especially near the peaks.
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Kelbulan, Emanuel ,., Jane S. Tambas, and Oktavianus ,. Parajouw. "DINAMIKA KELOMPOK TANI KALELON DI DESA KAUNERAN KECAMATAN SONDER." AGRI-SOSIOEKONOMI 14, no. 3 (2018): 55. http://dx.doi.org/10.35791/agrsosek.14.3.2018.21534.
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This study aims to see how the dynamics of the Kalelon farmer groups are examined from the elements of group dynamics. This research took place for 3 months from October to December 2017. The research site was in Kauneran Village, Sonder Sub-district. Data collection techniques carried out in this study were interview techniques. Sample selection using the method purposive sampling. The number of respondents is 15 people who are members of the group. The analysis technique used in this study is a qualitative descriptive analysis technique. The results showed that the Kalelon farmer group was dynamic because of the nine elements of group dynamics consisting of group goals, group structure, group development and coaching, group cohesiveness, group task functions, group atmosphere, group effectiveness, and hidden intentions were dynamic or good dynamic even though there is one element that is not dynamic, namely pressure in the group. *eprm*.
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Govoreanu, R., H. Saveyn, P. Van der Meeren, I. Nopens, and P. A. Vanrolleghem. "A methodological approach for direct quantification of the activated sludge floc size distribution by using different techniques." Water Science and Technology 60, no. 7 (2009): 1857–67. http://dx.doi.org/10.2166/wst.2009.535.
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The activated sludge floc size distribution (FSD) is investigated by using different measurement techniques in order to gain insight in FSD assessment as well as to detect the strengths and limitations of each technique. A second objective was to determine the experimental conditions that allow a representative and accurate measurement of activated sludge floc size distributions. Laser diffraction, Time Of Transition (TOT) and Dynamic Image Analysis (DIA) devices were connected in series. The sample dilution liquid, the dilution factor and hydraulic flow conditions avoiding flocculation proved to be important. All methods had certain advantages and limitations. The MastersizerS has a broader dynamic size range and provides accurate results at high concentrations. However, it suffers from an imprecise evaluation of small size flocs and is susceptible to particle shape effects. TOT suffers less from size overestimation for non-spherical particles. However, care should be taken with the settings of the transparency check. Being primarily a counting technique, DIA suffers from a limited size detection range but is an excellent technique for process visualization. All evaluated techniques turned out to be reliable methods to quantify the floc size distribution. Selection of a certain method depends on the purpose of the measurement.
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Zhao, Chunyu, Yan Cui, Xiaoyu Zhou, and Ying Wang. "Evaluation of Performance of Different Methods in Detecting Abrupt Climate Changes." Discrete Dynamics in Nature and Society 2016 (2016): 1–14. http://dx.doi.org/10.1155/2016/5898697.
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We compared and evaluated the performance of five methods for detecting abrupt climate changes using a time series with artificially generated abrupt characteristics. Next, we analyzed these methods using annual mean surface air temperature records from the Shenyang meteorological station. Our results show that the movingt-test (MTT), Yamamoto (YAMA), and LePage (LP) methods can correctly and effectively detect abrupt changes in means, trends, and dynamic structure; however, they cannot detect changes in variability. We note that the sample size of the subseries used in these tests can affect their results. When the sample size of the subseries ranges from one-quarter to three-quarters of the jump scale, these methods can effectively detect abrupt changes; they perform best when the sample size is one-half of the jump scale. The Cramer method can detect abrupt changes in the mean and trend of a series but not changes in variability or dynamic structure. Finally, we found that the Mann-Kendall test could not detect any type of abrupt change. We found no difference in the results of any of the methods following removal of the mean, creation of an anomaly series, or normalization. However, detrending and study period selection affected the results of the Cramer and Mann-Kendall methods; in the latter case, they could lead to a completely different result.
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Atasever, Sema, Zafer Aydın, Hasan Erbay, and Mostafa Sabzekar. "Sample Reduction Strategies for Protein Secondary Structure Prediction." Applied Sciences 9, no. 20 (2019): 4429. http://dx.doi.org/10.3390/app9204429.
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Predicting the secondary structure from protein sequence plays a crucial role in estimating the 3D structure, which has applications in drug design and in understanding the function of proteins. As new genes and proteins are discovered, the large size of the protein databases and datasets that can be used for training prediction models grows considerably. A two-stage hybrid classifier, which employs dynamic Bayesian networks and a support vector machine (SVM) has been shown to provide state-of-the-art prediction accuracy for protein secondary structure prediction. However, SVM is not efficient for large datasets due to the quadratic optimization involved in model training. In this paper, two techniques are implemented on CB513 benchmark for reducing the number of samples in the train set of the SVM. The first method randomly selects a fraction of data samples from the train set using a stratified selection strategy. This approach can remove approximately 50% of the data samples from the train set and reduce the model training time by 73.38% on average without decreasing the prediction accuracy significantly. The second method clusters the data samples by a hierarchical clustering algorithm and replaces the train set samples with nearest neighbors of the cluster centers in order to improve the training time. To cluster the feature vectors, the hierarchical clustering method is implemented, for which the number of clusters and the number of nearest neighbors are optimized as hyper-parameters by computing the prediction accuracy on validation sets. It is found that clustering can reduce the size of the train set by 26% without reducing the prediction accuracy. Among the clustering techniques Ward’s method provided the best accuracy on test data.
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Falcnik, Michal, Petr Novosad, Pavel Pesek, and Mylos Kytka. "Applicability of Sub-Size Charpy Specimens to Transition Behaviour of RPV Materials." Key Engineering Materials 348-349 (September 2007): 977–80. http://dx.doi.org/10.4028/www.scientific.net/kem.348-349.977.
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The advancement of proper methodology to determination of VVER reactor pressure vessel (RPV) materials transition behaviour has been followed. The project included selection of proper specimen geometries (standard 10x10x55 mm, sub-size 3x4x27 mm and 5x5x27.5 mm Charpy-V samples) and impact as well as dynamic fracture toughness testing. All the fundamental criterions have been applied to consider an applicability of small-sized specimens to Cr-Mo-V and Cr-Ni-Mo-V steel radiation embrittlement studies. Selected specimen geometries have been found to be fully valid for impact and dynamic fracture data and capable for prediction of standard specimen behaviour from the small specimens. Within testing of irradiated materials, it has been found not fully validity of all the compared transition temperatures.
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Shatokhin, K. S., S. V. Nikitin, V. I. Zaporozhets, et al. "LARGE-COPIOUS MINIPIGS OF ICG SB RAS: POTENTIAL OF UNREALIZABLE OPPORTUNITIES." Bulletin of NSAU (Novosibirsk State Agrarian University), no. 3 (October 24, 2020): 137–47. http://dx.doi.org/10.31677/2072-6724-2020-56-3-137-147.
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This publication presents the results of the analysis of the dynamics of changes in the largefruited indicators of the breeding group of minipigs of the ICG SB RAS. The analysis showed that the four large-copious indicators are divided into two pairs. The first pair is made up of sample values of the characteristic: average and maximum. These indicators are characterized by stability throughout the studied period. The second pair includes the sample minimum values and standard deviations of the trait. These two indicators are dynamic: the sample minimum values are characterized by a decrease, and the sample standard deviations are characterized by a uniform increase, described by linear regression equations. It is shown that the dynamic characteristics are related to each other. It is determined that in this complex, the leader is the minimum value, and the follower is the standard deviation. This is explained by the fact that an increase in the standard deviation is associated with a decrease in the minimum value and the stability of the maximum in the studied period of time. The result of this process is the growth of the genetic potential in the breeding group, which is responsible for the high weight of the newborn individual. However, due to the small size of sows in comparison with commercial breeds (60-70 kg), this potential cannot be realized. Nevertheless, its redundancy ensures the stabilization of the maximum and average values of the trait - the mass of a newborn individual in minipigs of the ICG SB RAS. A possible way to increase the realization of the potential of large-copious breeding group is to reduce the multiple fertility of sows, which is quite solvable, but hardly advisable. Thus there is natural selection directed against individuals with a low birth weight in the herd. Natural and artificial selection for live weight of piglets at birth of 700 g or more, both help to stabilize the average value of the trait at the level optimal for the broodstock.
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Pande, S., L. Arkesteijn, H. H. G. Savenije, and L. A. Bastidas. "Hydrological model parameter dimensionality is a weak measure of prediction uncertainty." Hydrology and Earth System Sciences Discussions 11, no. 3 (2014): 2555–82. http://dx.doi.org/10.5194/hessd-11-2555-2014.
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Abstract. This paper presents evidence that model prediction uncertainty does not necessarily rise with parameter dimensionality (the number of parameters). Here by prediction we mean future simulation of a variable of interest conditioned on certain future values of input variables. We utilize a relationship between prediction uncertainty, sample size and model complexity based on Vapnik–Chervonenkis (VC) generalization theory. It suggests that models with higher complexity tend to have higher prediction uncertainty for limited sample size. However, model complexity is not necessarily related to the number of parameters. Here by limited sample size we mean a sample size that is limited in representing the dynamics of the underlying processes. Based on VC theory, we demonstrate that model complexity crucially depends on the magnitude of model parameters. We do this by using two model structures, SAC-SMA and its simplification, SIXPAR, and 5 MOPEX basin data sets across the United States. We conclude that parsimonious model selection based on parameter dimensionality may lead to a less informed model choice.
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Aravanopoulos, F. A. "Genetic monitoring in natural perennial plant populations." Botany 89, no. 2 (2011): 75–81. http://dx.doi.org/10.1139/b10-087.
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Genetic monitoring, the quantification of temporal changes in population genetics and dynamics metrics generated by using appropriate parameters, constitutes a method with a prognostic value. Genetic monitoring has been recognized in several international agreements and documents, and can be an important tool for the protection of biodiversity. However, approaches developed so far for perennial plant species are rather cumbersome for practical use. It is proposed that perennial plant genetic monitoring should focus on keystone species of biological and economical importance, as well as rare or endangered species. In addition, genetic monitoring should concentrate on gene conservation units of such species, to be advanced in a dynamic gene conservation scheme. Three indicators are proposed for genetic monitoring based on a gene-ecological approach: natural selection, genetic drift, and a gene flow-mating system. These are evaluated based on three demographic (age and size class distribution, reproductive fitness, regeneration abundance) and four genetic (effective population size, allelic richness, latent genetic potential, outcrossing/actual inbreeding rate) parameters. Minimum sample sizes, critical levels of differences among parameters, and costs for temporal evaluation are proposed. The benefits of the immediate application of genetic monitoring are highlighted.
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Duddigan, Sarah, Liz J. Shaw, Paul D. Alexander, and Chris D. Collins. "A Comparison of Physical Soil Organic Matter Fractionation Methods for Amended Soils." Applied and Environmental Soil Science 2019 (November 11, 2019): 1–12. http://dx.doi.org/10.1155/2019/3831241.
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Selecting a suitable physical fractionation method, to investigate soil organic matter dynamics, from the plethora that are available is a difficult task. Using five different physical fractionation methods, on soils either nontreated or with a history of amendment with a range of exogenous organic matter inputs (Irish moss peat; composted horse manure; garden compost) and a resulting range of carbon contents (6.8 to 22.2%), we show that method selection had a significant impact on both the total C recovered and the distribution of the recovered C between unprotected, physically protected, or chemically protected conceptual pools. These between-method differences most likely resulted from the following: (i) variation in the methodological fractions obtained (i.e., distinguishing between aggregate size classes); (ii) their subsequent designation to conceptual pools (e.g., protected versus unprotected); and (iii) the procedures used in sample pretreatment and subsequent aggregate dispersion and fractionation steps. The performance of each method also varied depending on the amendment in question. The findings emphasise the need for an understanding of the nature of the soil samples under investigation, and the stabilisation mechanism of interest, both prior to method selection and when comparing and interpreting findings from literature studies using different fractionation methods.
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Radac, Mircea-Bogdan, and Timotei Lala. "Learning Output Reference Model Tracking for Higher-Order Nonlinear Systems with Unknown Dynamics." Algorithms 12, no. 6 (2019): 121. http://dx.doi.org/10.3390/a12060121.
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This work suggests a solution for the output reference model (ORM) tracking control problem, based on approximate dynamic programming. General nonlinear systems are included in a control system (CS) and subjected to state feedback. By linear ORM selection, indirect CS feedback linearization is obtained, leading to favorable linear behavior of the CS. The Value Iteration (VI) algorithm ensures model-free nonlinear state feedback controller learning, without relying on the process dynamics. From linear to nonlinear parameterizations, a reliable approximate VI implementation in continuous state-action spaces depends on several key parameters such as problem dimension, exploration of the state-action space, the state-transitions dataset size, and a suitable selection of the function approximators. Herein, we find that, given a transition sample dataset and a general linear parameterization of the Q-function, the ORM tracking performance obtained with an approximate VI scheme can reach the performance level of a more general implementation using neural networks (NNs). Although the NN-based implementation takes more time to learn due to its higher complexity (more parameters), it is less sensitive to exploration settings, number of transition samples, and to the selected hyper-parameters, hence it is recommending as the de facto practical implementation. Contributions of this work include the following: VI convergence is guaranteed under general function approximators; a case study for a low-order linear system in order to generalize the more complex ORM tracking validation on a real-world nonlinear multivariable aerodynamic process; comparisons with an offline deep deterministic policy gradient solution; implementation details and further discussions on the obtained results.
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Lee, Sunghee, Ai Rene Ong, and Michael Elliott. "Exploring Mechanisms of Recruitment and Recruitment Cooperation in Respondent Driven Sampling." Journal of Official Statistics 36, no. 2 (2020): 339–60. http://dx.doi.org/10.2478/jos-2020-0018.
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AbstractRespondent driven sampling (RDS) is a sampling method designed for hard-to-sample groups with strong social ties. RDS starts with a small number of arbitrarily selected participants (“seeds”). Seeds are issued recruitment coupons, which are used to recruit from their social networks. Waves of recruitment and data collection continue until reaching a sufficient sample size. Under the assumptions of random recruitment, with-replacement sampling, and a sufficient number of waves, the probability of selection for each participant converges to be proportional to their network size. With recruitment noncooperation, however, recruitment can end abruptly, causing operational difficulties with unstable sample sizes. Noncooperation may void the recruitment Markovian assumptions, leading to selection bias. Here, we consider two RDS studies: one targeting Korean immigrants in Los Angeles and in Michigan; and another study targeting persons who inject drugs in Southeast Michigan. We explore predictors of coupon redemption, associations between recruiter and recruits, and details within recruitment dynamics. While no consistent predictors of noncooperation were found, there was evidence that coupon redemption of targeted recruits was more common among those who shared social bonds with their recruiters, suggesting that noncooperation is more likely to be a feature of recruits not cooperating, rather than recruiters failing to distribute coupons.
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Lemière, Bruno, Jeremie Melleton, Pascal Auger, et al. "pXRF Measurements on Soil Samples for the Exploration of an Antimony Deposit: Example from the Vendean Antimony District (France)." Minerals 10, no. 8 (2020): 724. http://dx.doi.org/10.3390/min10080724.
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Mineral exploration is increasingly challenging in inhabited areas. To evaluate the potential of soil analysis by pXRF (portable X-ray fluorescence) as a low-footprint exploration technique, we revisited a historic Sb district in an agricultural area and performed shallow-soil sampling (Ah and B horizons) along profiles across known veins to capture the endogenic geochemical anomaly signals. Despite an expected bias between pXRF measurements and laboratory analyses, the former effectively located the Sb veins, especially when using their multi-element capabilities. Composition data processing (CoDa) and horizon-selective sampling significantly improved the method’s efficiency. On-site measurements allow dynamic sampling and mapping, helping with faster, cost-effective sample selection for further laboratory investigations. Based on this case study, where similar geochemical patterns were obtained for both horizons, application of an on-site approach to a humic horizon can increase survey efficiency and decrease impacts.
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Mawby, William D., and Fred P. Hain. "EVALUATION OF PROCEDURES FOR ESTIMATING WITHIN-SPOT POPULATIONS OF DENDROCTONUS FRONTALIS (COLEOPTERA: SCOLYTIDAE) DURING A COLLAPSING EPIDEMIC." Canadian Entomologist 117, no. 9 (1985): 1083–91. http://dx.doi.org/10.4039/ent1171083-9.
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AbstractData from 87 trees within 21 natural infestations were used to estimate the population size of the southern pine beetle (Dendroctonus flontalis Zimmermann) under collapsing high-level conditions in North Carolina. Spots of K trees (1<K<12) were created by random selection without replacement from the initial pool. Samples of m trees (1<m<K) were then chosen from each simulated spot according to random and selective plans. These samples over m trees were then extrapolated to the full K tree spot by 1 of 3 scaling factors: percentage of trees sampled, percentage of diameter sampled, or percentage of phloem area sampled. In this manner the total numbers of parent adults, brood, and brood adults were estimated for each artificial spot. Proportional errors, defined as (observed value – expected value)/(observed value), were computed over 10 000 independent trials for a variety of sample sizes, spot sizes, and scaling factors. The precision of these errors, after a bias correction was applied, was used to compare the different schemes. Random-diameter and largest-diameter schemes were judged best because of their good precisions and ease of application. However, when these results were applied to the 21 natural infestations, the confidence intervals were found to be too narrow to include the expected number of estimates. A discussion of this shortcoming is discussed in relation to spot dynamics and its effect on the application of this sampling technique.
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Wu, Ruijing, Shaoxuan Liu, and Zhenyang Shi. "Customer Incentive Rebalancing Plan in Free-Float Bike-Sharing System with Limited Information." Sustainability 11, no. 11 (2019): 3088. http://dx.doi.org/10.3390/su11113088.
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Free-float bike-sharing (FFBS) systems have increased in popularity as a sustainable travel mode in recent years, especially in the urban areas of China. Despite the convenience such systems offer to customers, it is not easy to maintain an effective balance in the distribution of bikes. This study considers the dynamic rebalancing problem for FFBS systems, whereby user-based tactics are employed by incentivizing users to perform repositioning activities. Motivated by the fact that the problem is frequently faced by FFBS system operators entering a new market with limited information on travel demand, we adopt the ranking and selection approach to select the optimal incentive plan. We describe the system dynamics in detail, and formulate a profit maximization problem with a constraint on customer service level. Through numerical studies, we first establish that our procedure can select the optimal incentive plan in a wide range of scenarios. Second, under our incentive plan, the profit and service level can be improved significantly compared with the scenario without incentive provision. Third, in most cases, our procedure can achieve the optimal solution with a reasonable sample size.
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Parte-Esteban, Laura, and Pilar Alberca-Oliver. "New insights into dynamic efficiency: the effects of firm factors." International Journal of Contemporary Hospitality Management 27, no. 1 (2015): 107–29. http://dx.doi.org/10.1108/ijchm-08-2013-0342.
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Purpose – This paper aims to investigate the determinants of dynamic efficiency in the Spanish hotel industry. The study also aims to introduce a large number of variables potentially related to efficiency and performance measurement. In particular, it seeks to explore the association between efficiency scores and firm-specific factors (variables related to market conditions, business factors, audit variables, organisational forms and subsidiary variables). Design/methodology/approach – In this study, the data envelopment analysis (DEA) double-frontier approach is used according to firm size in conjunction with non-parametric tests (Mann–Whitney U and Kruskal–Wallis tests), a dynamic Tobit regression model and a bootstrapping procedure. The tests are performed using 1,805 hotels from the years 2002 to 2011. This allows the authors to overcome several of the major limitations of previous papers, namely, the low number of observations, the static or cross-sectional analysis referring to a single period and the use of conventional DEA models, among others. Findings – The results show significant differences in dynamic efficiency among Spanish hotel companies. In addition, the evidence suggests the levels of efficiency are related to the hotel's location, the hotel's size, internationalisation, the first source of the hotel's activity, audit service and management variables. Research limitations/implications – One limitation of the study is related to the input and output variables specified in the DEA model. The selection of inputs and outputs was based on data availability and the previous literature on hotel efficiency, but the results might change if the hotel sample and the selected input and output variables were changed. Another limitation is the availability of data on ownership structure and subsidiary variables for very small businesses. Originality/value – The paper contributes to the tourism literature by offering new insights into hotel performance: dynamic efficiency evaluation and its main determinants. The paper presents strategic market implications for hoteliers, government decision-makers and destination management organisations.
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Gonzalez Casanova, Adrian, та Charline Smadi. "On Λ-Fleming–Viot processes with general frequency-dependent selection". Journal of Applied Probability 57, № 4 (2020): 1162–97. http://dx.doi.org/10.1017/jpr.2020.55.
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AbstractWe construct a multitype constant-size population model allowing for general selective interactions as well as extreme reproductive events. Our multidimensional model aims for the generality of adaptive dynamics and the tractability of population genetics. It generalises the idea of Krone and Neuhauser [39] and González Casanova and Spanò [29], who represented the selection by allowing individuals to sample several potential parents in the previous generation before choosing the ‘strongest’ one, by allowing individuals to use any rule to choose their parent. The type of the newborn can even not be one of the types of the potential parents, which allows modelling mutations. Via a large population limit, we obtain a generalisation of $\Lambda$ -Fleming–Viot processes, with a diffusion term and a general frequency-dependent selection, which allows for non-transitive interactions between the different types present in the population. We provide some properties of these processes related to extinction and fixation events, and give conditions for them to be realised as unique strong solutions of multidimensional stochastic differential equations with jumps. Finally, we illustrate the generality of our model with applications to some classical biological interactions. This framework provides a natural bridge between two of the most prominent modelling frameworks of biological evolution: population genetics and eco-evolutionary models.
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Sadeghi Aghili, Seyed Ali, Omid Fatahi Valilai, Alireza Haji, and Mohammad Khalilzadeh. "Dynamic mutual manufacturing and transportation routing service selection for cloud manufacturing with multi-period service-demand matching." PeerJ Computer Science 7 (April 23, 2021): e461. http://dx.doi.org/10.7717/peerj-cs.461.
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Recently, manufacturing firms and logistics service providers have been encouraged to deploy the most recent features of Information Technology (IT) to prevail in the competitive circumstances of manufacturing industries. Industry 4.0 and Cloud manufacturing (CMfg), accompanied by a service-oriented architecture model, have been regarded as renowned approaches to enable and facilitate the transition of conventional manufacturing business models into more efficient and productive ones. Furthermore, there is an aptness among the manufacturing and logistics businesses as service providers to synergize and cut down the investment and operational costs via sharing logistics fleet and production facilities in the form of outsourcing and consequently increase their profitability. Therefore, due to the Everything as a Service (XaaS) paradigm, efficient service composition is known to be a remarkable issue in the cloud manufacturing paradigm. This issue is challenging due to the service composition problem’s large size and complicated computational characteristics. This paper has focused on the considerable number of continually received service requests, which must be prioritized and handled in the minimum possible time while fulfilling the Quality of Service (QoS) parameters. Considering the NP-hard nature and dynamicity of the allocation problem in the Cloud composition problem, heuristic and metaheuristic solving approaches are strongly preferred to obtain optimal or nearly optimal solutions. This study has presented an innovative, time-efficient approach for mutual manufacturing and logistical service composition with the QoS considerations. The method presented in this paper is highly competent in solving large-scale service composition problems time-efficiently while satisfying the optimality gap. A sample dataset has been synthesized to evaluate the outcomes of the developed model compared to earlier research studies. The results show the proposed algorithm can be applied to fulfill the dynamic behavior of manufacturing and logistics service composition due to its efficiency in solving time. The paper has embedded the relation of task and logistic services for cloud service composition in solving algorithm and enhanced the efficiency of resulted matched services. Moreover, considering the possibility of arrival of new services and demands into cloud, the proposed algorithm adapts the service composition algorithm.
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Abbood Bandar, Mohsin, Muntadher Kadhim Shamran, and Abeer M. Mahdi AL-shammari. "A STUDY OF RELATIONSHIP BETWEEN EMPLOYEE ENGAGEMENT AND JOB SATISFACTION IN THE KARBALA HEALTH DIRECTORATE." Humanities & Social Sciences Reviews 8, no. 4 (2020): 774–79. http://dx.doi.org/10.18510/hssr.2020.8477.
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Purpose: The study aims at identifying the relationship between employee engagement and job satisfaction in health institutions in Karbala city through a sample of health workers and administrators.
 Methodology: To achieve this goal, the theoretical literature on the two variables was reviewed. In addition, 240 questionnaires were distributed in these institutions using a random selection method. Finally, SPSS was used to analyze in this study. The researchers relied statistically on a model which indicated the statistical equation against which the minimum sample size required to represent the community can be correctly determined (N> 50 + 8 (P)) (Natarajan, 2006: 42), and this means that the sample size should be greater than of the number of independent sub-variables in the value of the constant (8) plus even a fixed amount of (50) views.
 Main Findings: The most significant consequences of the investigation are the enlistment techniques that guarantee the determination of the perfect individuals to work in occupations equivalent with their capabilities, and Ensuring the support of representatives in the structure of employment and dynamic procedure, just as interest in the improvement of clinical administrations.
 Application of Study: Effective human resource management and optimal investment of skills and abilities that can lead to the growth and survival of Karbala's health organizations and institutions.
 Novelty/Originality: This investigation attempts to investigate the most unmistakable news esteems on the front pages of Al Ghad and Al Rai papers just as recognize the contrasts between them regarding the sorts of the news, the sources, and the method of showing them.
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Tahir, Rizwan. "Expanding horizons and expatriate adjustment." Cross Cultural & Strategic Management 25, no. 3 (2018): 401–24. http://dx.doi.org/10.1108/ccsm-02-2017-0024.
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Purpose Expatriate management is a popular theme in the field of international human resource management in light of the fact that expatriates play a crucial role in a MNC’s global operations. The purpose of this paper is to explore how MNCs select, train, deploy and support expatriate managers during and after their international assignment in the United Arab Emirates (UAE). Design/methodology/approach This qualitative study is based on in-depth interviews with 22 Western expatriate managers who are presently based in the UAE. However, in order the ensure a diverse sample among the participants with regards to their age, professional experience, gender and nationality, purposeful sampling was utilized while selecting the participants. Findings The results of the present study cast light on many shortcomings of the overall expatriation process as they are implemented by MNCs in the UAE. Accordingly, there is a pressing need for MNCs in the UAE to develop strategic expatriation processes, involving the following critical factors: the selection of the right person for the right job; specific and relevant pre-departure and post-arrival cross-cultural training (CCT); practical support for the expatriate employees and their trailing spouses in the host country; and lastly, a clear repatriation strategy to mark a successful conclusion of foreign assignments in the UAE. Research limitations/implications It is acknowledged that the results of this purely qualitative study, based on a relatively small sample size, cannot claim to represent the management theories, practices and realities of all the Western MNCs in the UAE. Moreover, these findings narrate the views and perceptions of this particular cohort of expatriate executives with relation to their selection, pre-departure CCT, adjustment in the UAE and the support and repatriation policies utilized by their companies for doing business in the UAE. Practical implications This study points to the fact that technical skills are mostly considered to be the predominant selection criteria for the expatriate selections in the MNCs. Other abilities, such as language skills and relational and perceptual adjustability are considered to be less important and do not feature overtly in the selection criteria for expatriate positions. The results demonstrate that distinctive features of adjustability, which include expatriates’ willingness to communicate, their social orientation, dynamic anxiety resistance and openness ability are all critical to the adjustment in the host country and should be given more emphasis. Originality/value Regardless of the presence of numerous MNCs in the UAE, it is indeed surprising to see that the topic of the expatriation management process in MNCs in the UAE has received little research attention. The objective of this study is to address this deficiency. Additionally, it is hoped that these findings may also be valuable to MNCs and consultants who are preparing expatriates for international assignments, especially in the Middle East and in particular in the UAE.
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Almarashi, Abdullah M., Ali Algarni, Amal S. Hassan, Ahmed N. Zaky, and Mohammed Elgarhy. "Bayesian Analysis of Dynamic Cumulative Residual Entropy for Lindley Distribution." Entropy 23, no. 10 (2021): 1256. http://dx.doi.org/10.3390/e23101256.
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Dynamic cumulative residual (DCR) entropy is a valuable randomness metric that may be used in survival analysis. The Bayesian estimator of the DCR Rényi entropy (DCRRéE) for the Lindley distribution using the gamma prior is discussed in this article. Using a number of selective loss functions, the Bayesian estimator and the Bayesian credible interval are calculated. In order to compare the theoretical results, a Monte Carlo simulation experiment is proposed. Generally, we note that for a small true value of the DCRRéE, the Bayesian estimates under the linear exponential loss function are favorable compared to the others based on this simulation study. Furthermore, for large true values of the DCRRéE, the Bayesian estimate under the precautionary loss function is more suitable than the others. The Bayesian estimates of the DCRRéE work well when increasing the sample size. Real-world data is evaluated for further clarification, allowing the theoretical results to be validated.
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Landau, Dan A., Clare Sun, Daniel Rosebrock, et al. "The Landscape of Dynamic Genetic Changes in Ibrutinib-Treated CLL." Blood 128, no. 22 (2016): 188. http://dx.doi.org/10.1182/blood.v128.22.188.188.
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Abstract Cancer evolution poses a significant challenge to the ability of therapy to eliminate malignant cells. In chronic lymphocytic leukemia (CLL), clonal evolution was reported as a key feature of disease relapse after standard chemoimmunotherapy and after targeted therapy with the BTK inhibitor ibrutinib. To study potential selection of pre-existing sub-clones, we analyzed changes in clonal architecture at early time points in patients receiving ibrutinib therapy. We therefore performed in-depth longitudinal analysis of CLL samples collected from 59 patients treated with ibrutinib alone (n=44) or in combination with rituximab (n=15). Across this cohort, we performed whole-exome sequencing (WES) on a median of 3 samples per patient with median coverage of 105x (range 50-225x). Pretreatment samples were available for all patients, with post-treatment samples at 1 and 6 months for more than 85% of patients. Additional samples were available at 2, 3, or 12 months for 22 patients. The median age of the cohort was 65 (range 33-85) years. Thirty-one patients (53%) had del(17p) by FISH, 37 patients (63%) had IGHV unmutated CLL and 32 patients (54%) had relapsed or refractory disease. We observed a median of 56 (range 17-201) somatic silent and non-silent single nucleotide variants (SNVs) and insertions and deletions (Indels) per patient. The number of SNVs and indels did not differ between patients receiving ibrutinib alone or with rituximab (Wilcoxon, P=0.2). Thirteen patients had somatic mutations of BCR pathway genes prior to treatment, including one with CARD11-L251P, previously reported to confer resistance to ibrutinib in diffuse large B-cell lymphoma. Comparing pre-treatment and the latest samples within the first year (range 56-357 days, median 168), 26 of 59 (44%) CLLs showed significant changes in cancer cell fraction (CCF) over time, defined as a shift > 5% CCF of the clone with the greatest change (BH-FDR <0.1). These included 11 CLLs with a clone that significantly increased in size, 9 with a clone that significantly decreased in size, and 6 with significant reciprocal rises and falls of different clones consistent with a branched evolutionary pattern. The median CCF change during the observation period was 24% (range 7-89%). Thus, even within a short period of treatment exposure, dense temporal sampling of CLLs reveals that ibrutinib therapy commonly leads to clonal shifts. The likelihood for clonal shifts was not impacted by whether patients were treated with ibrutinib alone or with rituximab (45% vs. 40%, P=0.77), nor by exposure to prior therapy (47% vs. 41% with and without prior therapy, P=0.79). We observed trends towards higher likelihood of early clonal evolution in CLLs with unmutated IGHV status, with TP53 somatic aberrations, and those with a pre-treatment subclonal driver (subclones containing CHD2, BIRC3, SF3B1, MAP2K1, CARD11, XPO1, TP53, PTPN11, KRAS, HIST1H1E, ATM). Finally, patients with a decrease in ALC at 6 months compared to pre-treatment were more likely to exhibit significant CCF shifts (P=0.01). This last observation suggests that effective treatment activity and resulting therapeutic bottlenecks indeed contribute to the shift in clonal proportion within the first year of ibrutinib therapy. Relapse samples were available for 10 CLL cases, 6 of whom showed early clonal shifts during the first year of therapy. These included 2 cases of transformation to prolymphocytic leukemia (PLL), 2 with Richter transformation (RT) and 6 cases of progressive CLL disease. All relapse cases were clonally related to the pre-treatment samples. Mutations in BTK or PLCg2 were found in 5 cases by either WES or deep targeted sequencing of known resistance hotspots (both PLL, one RT, two progressive CLL). The remaining 5 cases showed marked clonal shifts suggestive of selection of other resistant genotypes. Altogether, targeted therapy with ibrutinib is associated with overall clonal stability in more than half of CLLs over the first year of treatment. Nevertheless, in many patients, clonal selection occurs even during the first months of therapy and may provide clues regarding the future evolutionary and clinical outcome of the disease. Disclosures Farooqui: Merck: Employment. Burger:Pharmacyclics, LLC, an AbbVie Company: Research Funding; Gilead: Research Funding; Janssen: Consultancy, Other: Travel, Accommodations, Expenses; Roche: Other: Travel, Accommodations, Expenses; Portola: Consultancy. Wiestner:Acerta Pharma: Research Funding; Pharmacyclics: Research Funding. Wu:Neon Therapeutics: Membership on an entity's Board of Directors or advisory committees, Other: Co-founder.
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Kornienko, Olga, Thomas J. Dishion, and Thao Ha. "Peer Network Dynamics and the Amplification of Antisocial to Violent Behavior Among Young Adolescents in Public Middle Schools." Journal of Emotional and Behavioral Disorders 26, no. 1 (2017): 21–30. http://dx.doi.org/10.1177/1063426617742345.
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This study examined longitudinal changes in peer network selection and influence associated with self-reported antisocial behavior (AB) and violent behavior (VB) over the course of middle school in a sample of ethnically diverse adolescents. Youth and families were randomly assigned to a school-based intervention focused on the prevention of substance use. Using a longitudinal social network modeling approach, we found that students with similar levels of AB were more likely to affiliate during the transition from sixth to seventh grade (peer selection). Higher levels of AB in the seventh grade led to growth in network size by eighth grade. No peer selection effects documented for VB, but youth became more similar to total levels of VB reported by their peers between seventh and eighth grades (peer influence). As expected, AB was positively associated with VB levels. Random assignment to intervention condition affected peer selection at Grade 7 but did not reduce levels of self-reported AB or VB. These findings suggest that managing peer networks using a variety of strategies is likely to reduce peer contagion for AB and VB in a public middle school setting. We discuss emerging intervention strategies for the management and the prevention of emotional and behavioral disorders.
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Moyo, Vusani. "Navigating The Debt-Equity Decisions Of Financial Services Firms: Some Evidence From South Africa." Journal of Applied Business Research (JABR) 32, no. 2 (2016): 417. http://dx.doi.org/10.19030/jabr.v32i2.9586.
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Empirical studies on the impact of regulation on the financial policies of banks have documented that unconstrained forward-looking banks with sufficient franchise value build and actively maintain capital buffers. This financing behaviour thus relegates the regulatory intervention to non-binding and of secondary importance. This study used a sample of 29 financial services firms listed on the Johannesburg Stock Exchange (JSE) during the period 2003 to 2012 to test for the validity of the market timing, pecking order and the dynamic trade-off theories in explaining the financing behaviour of financial services firms. Consistent with the dynamic trade-off theory and contrary to the market timing and pecking order theories, the study documents that, leverage is positively correlated to firm profitability, size and asset tangibility. The firms’ true speed of adjustment is 56.80% for the market-to-debt ratio (MDR) and 71.31% for the book-to-debt ratio (BDR). The modified external finance-weighted average market-to-book has an insignificant positive and negative correlation with the MDR and the BDR respectively. Taken together, the JSE-listed financial services firms have target optimal capital structures which they actively adjusts towards. Their security issuance decisions are not driven by the stock market performance, share returns or the time-varying adverse selection costs.
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Long, J. C. "The genetic structure of admixed populations." Genetics 127, no. 2 (1991): 417–28. http://dx.doi.org/10.1093/genetics/127.2.417.
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Abstract A method for simultaneously estimating the admixture proportions of a hybrid population and Wright's fixation index, FST, for that hybrid is presented. It is shown that the variance of admixture estimates can be partitioned into two components: (1) due to sample size, and (2) due to evolutionary variance (i.e., genetic drift). A chi-square test used to detect heterogeneity of admixture estimates from different alleles, or loci, can now be corrected for both sources of random errors. Hence, its value for the detection of natural selection from heterogeneous admixture estimates is improved. The estimation and testing procedures described above are independent of the dynamics of the admixture process. However, when the admixture dynamics can be specified, FST can be predicted from genetic principles. Two admixture models are considered here, gene flow and intermixture. These models are of value because they lead to very different predictions regarding the accumulation of genes from the parental populations and the accumulation of variance due to genetic drift. When there is not evidence for natural selection, and it is appropriate to apply these models to data, the variance effective size (Ne) of the hybrid population can be estimated. Applications are made to three human populations: two of these are Afro-American populations and one is a Yanomamö Indian village. Natural selection could not be detected using the chi-square test in any of these populations. However, estimates of effective population sizes do lead to a richer description of the genetic structure of these populations.
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Surowiak, Agnieszka, Tomasz Gawenda, Agata Stempkowska, Tomasz Niedoba, and Alona Nad. "The Influence of Selected Properties of Particles in the Jigging Process of Aggregates on an Example of Chalcedonite." Minerals 10, no. 7 (2020): 600. http://dx.doi.org/10.3390/min10070600.
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The influence of the physical, geometric and chemical properties of particles on the results of aggregate separation by means of a laboratory ring jig is presented in this paper. The experiment was based on separation of chalcedonite particles in a narrow particle size fraction composed separately of regular and irregular particles, which was prepared in accordance with patent inventions. On its basis, the geometric properties—projection diameter and (volumetric and dynamic) shape coefficients—as well as physical properties—particle density—were determined in products of the regular and irregular particles. The terminal settling velocities of the regular and irregular particles were calculated for a randomly selected sample of particles in each obtained separation product. The statistical analysis of the geometric properties of the particles allowed to evaluate the influence of these parameters on aggregate processing with respect to selection of particles homogenous in terms of their shapes. The comparison of the particle shapes’ influence on the chalcedonite feed separation effects was made by the means of the values of the shape coefficients: the dynamic and volumetric ones. Additionally, tests were carried out using Raman spectroscopy in order to determine the mechanisms of density change in the aggregate. The research goal was realised through detecting and analysing the polymorphic forms of the silica and allogenic minerals precipitated on the surface and inside the chalcedonite particles.
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SILVA, L. K., S. LIU, and R. E. BLANTON. "Microsatellite analysis of pooled Schistosoma mansoni DNA: an approach for studies of parasite populations." Parasitology 132, no. 3 (2005): 331–38. http://dx.doi.org/10.1017/s0031182005009066.
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Human parasites are often distributed in metapopulations, which makes random sampling for genetic epidemiology difficult. The typical approach to sampling Schistosoma mansoni involves laboratory passage to obtain individual worms with small sample size and selection bias as a consequence. By contrast, the naturally pooled samples from egg output in stool or urine directly represent the genetic composition of current populations. To test whether pooled samples could be used to estimate population allele frequencies, DNA from individual cloned parasites was pooled and amplified by PCR for 7 microsatellites. By polyacrylamide gel analysis, the relative band intensities of the products from the major alleles in the pooled samples differed by 0–6% from the summed intensities of the individual clones (mean=2·1%±2·1% S.D.). The number of PCR cycles (25–40) did not influence the accuracy of the estimate. Varying the frequency of 1 allele in pooled samples from 32 to 69% likewise did not affect accuracy. Allele frequency estimates from aggregate samples such as eggs will be a better foundation for studies of parasite population dynamics as well as the basis for large-scale association studies of host and parasite characteristics.
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Barsky, Victor, Alexander Perov, Sergei Tokalov, et al. "Fluorescence Data Analysis on Gel-Based Biochips." Journal of Biomolecular Screening 7, no. 3 (2002): 247–57. http://dx.doi.org/10.1177/108705710200700308.
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A series of biochip readers developed for gel-based biochips includes three imaging models and a novel nonimaging biochip scanner. The imaging readers, ranging from a research-grade versatile reader to a simple portable one, use wide-field objectives and 12-bit digital large-coupled device cameras for parallel addressing of multiple array elements. This feature is valuable for monitoring the kinetics of sample interaction with immobilized probes. Depending on the model and the label used, the sensitivity of these readers approaches 0.3 amol of a labeled sample per gel element. In the selective scanner, both the spot size of the excitation laser beam and the detector field of view match the size of the biochip array elements so that the whole row of the array can be read in a single scan. The portable version reads 50-mm long, 150-element, one-dimensional arrays in 5 s. With a dynamic range of 4000:1, a sensitivity of 1-5 amol of a labeled sample per gel element, and a data format facilitating online processing, the scanner is an attractive, inexpensive solution for biomedical diagnostics. Fluorophores for sample labeling were compared experimentally in terms of detection sensitivity, influence on duplex stability, and suitability for multilabel analysis and thermodynamic studies. Texas Red and tetracarboxyphenylporphyn proved to be the best choice for two-wavelength analysis using the imaging readers.
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Fedotova, T. K., and A. K. Gorbacheva. "Secular Dynamics of Body Height and Weight in Russian Children Aged 0–17." Archaeology, Ethnology & Anthropology of Eurasia 47, no. 3 (2019): 145–57. http://dx.doi.org/10.17746/1563-0110.2019.47.3.145-157.
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This study deals with long-term temporal changes of body height and weight during various stages of ontogeny: newborns, infancy, early age, fi rst childhood, second childhood, adolescence, and youth. Each age/sex group numbers ca 100 persons, the total sample size is ca 2 000. The meta-analysis is based primarily on growth standards for Russian children, regularly renewed by the Research Institute for the Hygiene and Health Protection of Children and Adolescents and mostly relating to separate decades of the 20th century. The intensity of the secular trends was assessed through the analysis of scatter plots. The largest share in the secular increase of bodily dimensions belongs to intense growth during the second year of life and during the adolescent growth spurt. The smallest share is that of intrauterine growth, limited by the mother’s body size, and that of growth during adolescence, when the mature body size has been virtually reached and growth rate is minimal. Boys, who are more eco-sensitive, demonstrate greater secular changes than girls, who are eco-resistant. Smaller secular changes in weight than in height in both boys and girls result in the increase of leptosomy. This heterochrony concerns mostly newborns, whose body mass is a standard example of stabilizing selection.
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Yan, Yuting, Yan Xu, Xuehan Mao, et al. "Monitoring the Cytogenetic Architecture of Minimal Residual Plasma Cells Indicates Therapy-Induced Clonal Selection in Multiple Myeloma." Blood 134, Supplement_1 (2019): 4405. http://dx.doi.org/10.1182/blood-2019-124096.
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Background: Recent attempts have focused on identifying fewer magnitude of minimal residual disease (MRD) rather than exploring the biological and genetic features of the residual plasma cells (PCs). Interphase fluorescence in situ hybridization (iFISH) analyses in sequential samples provide a simple and reliable method to longitudinal track the dynamic changes in clonal architecture and speculate the possible evolutionary pattern. Here, we report for the first time the incidence and prognostic significance of cytogenetic abnormalities (CA) existed in the PCs of patients achieving at least partial remission. Methods: A cohort of 193 patients with at least one CA at diagnosis were analyzed using data from the prospective, non-randomized clinical trial (BDH 2008/02), and iFISH analyses were performed in patient-paired diagnostic and post-therapy samples. Results: Persistent CA in residual tumor cells were observed for the majority of patients (63%), even detectable in 28/63 (44%) patients with MRD negativity (<10-4). The absence of CA in residual PCs was associated with prolonged survival regardless of MRD status. It was noted that MRD-positive but FISH-negative patients experienced similar survival to MRD-negative patients (m-TTP 4.5 vs. 5.1 years, P=0.983). According to the change of the clonal size of specific CA, patients were clustered into five groups, reflecting five patterns of clone selection under therapy pressure. 1) Pattern A were observed in 36 (19%) patients where a minor subpopulation or undetectable subclone in the pre-treatment sample became dominant after therapy. 2) Pattern B was identified in 29 (15%) patients whose fractions of PCs harboring different CA were decreased with inconsistent extent. 3) Identical CA fraction in residual PCs were found in 22 (11%) patients as Pattern C. 4) Pattern D. The fractions of PCs harboring specific CA in 35 patients (18%) were uniformly declined. 5) 71 patients lost their abnormal cytogenetic clone after therapy (less than cut-off level) were classified as Pattern E. The cytogenetic dynamics of pattern A and B can be interpreted as a therapy-induced selection process with comparable inferior survival (m-TTP 1.2 vs. 1.6 years, respectively). Patients with pattern E experienced the most favorable outcome (m-TTP 5.0 years), following those with pattern D and C (m-TTP 3.5 and 2.5 years). Among the 65 patients with clonal selection, 24 underwent upfront auto-transplantation that experienced significantly improved survival. However, upfront transplant failed to completely reverse the inferior outcome caused by therapy-induced clonal selection. Longitudinal cytogenetic studies at relapse were available in 43 patients. The results suggested that sequential cytogenetic dynamics were observed in most patients, and the cytogenetic architecture of residual cells could to some extent predict the evolutional pattern at relapse. Conclusions: The repeat cytogenetic evaluation in residual cells could not only serves as a good complementary tool for MRD detection, but also provides a better understanding of clinical response and clonal evolution. Therapy-induced clonal selection was associated with inferior outcome regardless of the baseline cytogenetic profiles. The early identification of resistant clone may contribute to guide better tailored therapy strategies based on the feature of the residual tumor cells. Figure Disclosures Munshi: Celgene: Consultancy; Adaptive: Consultancy; Oncopep: Consultancy; Amgen: Consultancy; Janssen: Consultancy; Takeda: Consultancy; Abbvie: Consultancy.
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Liu, Rong, Xia Guo, Qiujin Peng, et al. "Stratified body shape-driven sizing system via three-dimensional digital anthropometry for compression textiles of lower extremities." Textile Research Journal 88, no. 18 (2017): 2055–75. http://dx.doi.org/10.1177/0040517517715094.
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Poor fit has become one of reasons for high non-compliance in the use of garments made of compression textiles in venous deficiency treatments. A novel methodology to categorize lower body shapes and sizes has been established via three-dimensional digital anthropometric technology in this study based on 208 Hong Kong subjects aged 40–60 years. Three new parameters were introduced to classify body shapes, namely the “A-angle” for assessing the “alignment” of lower extremities, the “cosine values of the key angle” at the turning point for below-knee shape determination, and “gradient” for above-knee shape categories. The mathematical simulation via the interpolation function was employed to explore the characteristics of shape variation trends with the involvement of dynamic interactions of both circumferences ( Cir) and heights ( Hei) of lower extremities. The clustering analysis quantitatively segmented the sample population into three stratified leg morphologies (i.e. diamond, inverted trapezoid, and balanced leg shapes) in terms of the determined anthropometric landmarks along the lower extremities, in which the C ir( s) of the brachial ( cB1), calf ( cC), and thigh ( cF) exhibited most obvious differences among the clustered lower limbs. The created stratified shape-driven sizing system and methodologies further involved the body shape classifications into the Cir-based size categories to cater for diverse body morphologies in product size selection, thus improving dimensional fitness and accurate treatment using compression textiles in practice.
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Ebbestad, Jan Ove R., and Christopher A. Stott. "Failed predation in Late Ordovician gastropods (Mollusca) from Manitoulin Island, Ontario, CanadaThis article is one of a selection of papers published in this Special Issue on the theme The dynamic reef and shelly communities of the Paleozoic. This Special is in honour of our colleague and friend Paul Copper." Canadian Journal of Earth Sciences 45, no. 2 (2008): 231–41. http://dx.doi.org/10.1139/e07-052.
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Shell repairs resulting from presumed failed predation are documented in gastropods from the Late Ordovician (Cincinnatian; Richmondian) mid-to-upper Kagawong Submember of the Georgian Bay Formation on Manitoulin Island, Ontario, Canada. The bryozoan–mollusc biota and associated sediments generally suggest nearshore, shallow (<10 m), low energy (lagoonal), and perhaps mesotrophic to eutrophic conditions. Two sample sets from this unit have been studied for shell repair. One of the more commonly applied estimates of shell repair frequencies involves division of the number of individuals with at least one scar by the total number of individuals in the sample (the Individuals with scars method). Using this calculation, 207 specimens of Lophospira trilineata Ulrich and Scofield yielded a shell repair frequency of 4.8%; in 28 specimens of Trochonemella sp. the shell repair frequency was 35.7%. Repairs in Trochonemella occur primarily in the larger size class, suggesting that a size refuge was achieved by this species. Low repair frequencies in L. trilineata suggest predation with a higher success rate or fewer encounters. This study demonstrates that the paradigm of a standardized low level of shell repair in Ordovician and Silurian gastropods is oversimplistic and a range of frequency rates can be expected.
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Soleimani, V. D., B. R. Baum, and D. A. Johnson. "Quantification of the retrotransposon BARE-1 reveals the dynamic nature of the barley genome." Genome 49, no. 4 (2006): 389–96. http://dx.doi.org/10.1139/g05-119.
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We used quantitative real-time PCR analysis to measure the copy number of the BARE-1 retrotransposon in 5 cultivars of barley (Hordeum vulgare), as well as in samples from its wild relative, Hordeum spontaneum. Two sets of PCR primers were used to amplify regions within the long terminal repeat (LTR) and the reverse transcriptase (RT) gene of BARE-1 (GenBank accession Z17327). The LTR primers detected an average of 2.148 × 105 ± 0.012 × 105 copies per haploid genome among barley samples, whereas the RT primers detected an average of 1.588 × 104 ± 0.085 × 104 copies. The average ratio of LTR:RT was estimated to be 13.5:1. This finding indicates that more than 7% of the barley genome is occupied by BARE-1 elements in the form of solo LTRs and another 2.6% of the genome is occupied by the full-length element. Taken together, BARE-1 sequences represent approximately 9.6% of the barley genome among the barley plants used in this study. For the above estimation, a genome size of 5.44 × 103 Mb for H. vulgare and 5.39 × 103 Mb for H. spontaneum were assumed. Our study on quantification results of the BARE-1 for a small group of barley cultivars showed that there are significant differences among cultivars in terms of BARE-1 copy number, providing further evidence that BARE-1 is active and has a major role in shaping the barley genome as a result of breeding and selection. Quantification results also showed that most of the elements (> 90%) are present as truncated copies (solo LTRs). These results show that there is a high level of recombination leading to the formation of truncated elements and a subsequent DNA loss from the genome. Taken together, our study provides a glimpse into a dynamic micro-evolutionary process that is the by-product of genome reshuffling and directional selection in barley breeding programsKey words: BARE-1, genome evolution, quantification, real-time PCR, retrotransposons.
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Carbajales-Lopez, Julia, Ricardo Becerro-de-Bengoa-Vallejo, Marta Elena Losa-Iglesias, et al. "The OptoGait Motion Analysis System for Clinical Assessment of 2D Spatio-Temporal Gait Parameters in Young Adults: A Reliability and Repeatability Observational Study." Applied Sciences 10, no. 11 (2020): 3726. http://dx.doi.org/10.3390/app10113726.
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Background: Walking clinical assessments are commonly used to check for possible gait modifications in healthy subjects, in patients with trauma or neurological conditions, or after a surgical procedure. Spatio-temporal walking variables are studied in depth to achieve a complete evaluation. The purpose of this study was to perform an observational study of the reliability and repeatability of the OptoGait portable photoelectric cell system. Methods: An observational study of the reliability and repeatability of the OptoGait portable photoelectric cell system was carried out. Results: Walking point, walking point gap, step width, and walking base variables, which are deeply related to gait and posture, have an almost perfect reliability. Conclusion: The OptoGait motion analysis device is a reliable system for clinical assessment of static and dynamic foot pressures. Clinicians should feel confident adding this analysis system to their daily professional tools where repeatable measures of gait measurements are important for diagnosis and treatment selection, and also compare efficacy or testing differences between different pathologic conditions. Further, these obtained data can be formed as a baseline for future studies, and to check a right sample size for new research that use the OptoGait motion analysis system.
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CAPOBIANCO, ENRICO. "ALIASING IN GENE FEATURE DETECTION BY PROJECTIVE METHODS." Journal of Bioinformatics and Computational Biology 07, no. 04 (2009): 685–700. http://dx.doi.org/10.1142/s0219720009004254.
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Because of measurements obtained under limited experimental conditions or time points compared to the presence of many genes, also known as the "large dimension, small sample size" problem, dimensionality reduction techniques are a common practice in statistical bioinformatics involving microarray analysis. However, in order to improve the performance of reverse engineering and statistical inference procedures aimed to estimate gene–gene connectivity links, some kind of regularization is usually needed to reduce the overall data complexities, together with ad hoc feature selection to uncover biologically relevant gene associations. The paper deals with feature selection by projective methods; in particular, it addresses some issues: Can the impact of noise on the data be limited by shrinkage or de-noising? How can complexity from convoluted dynamics associated with microarray measurements be discounted? In modeling such data, how to deal with over-parametrization, and control it? The problem of aliasing is then discussed and classified into two categories according to the trade-off between biological relevance and noise, and finally reported in analytical form via subspace analysis.
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Zimmermannova, Olga, Ondrej Hrusak, Eva Fronkova, et al. "Dynamics and Evolution of the Preleukemic Clone in Slow Onset Leukemias." Blood 120, no. 21 (2012): 1306. http://dx.doi.org/10.1182/blood.v120.21.1306.1306.
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Abstract Abstract 1306 Introduction Acute lymphoblastic leukemia (ALL) can rarely be manifested before its diagnosis as pancytopenia and bone-marrow aplasia followed by spontaneous transient hematological remission. A leukemic clone can be detected during this particular period, making it possible to follow its dynamics in size, as well as independent changes leading to the overt disease. Patients and methods We initially selected 5 cases of ALL, in which the pre-diagnostic period of anemia had occurred. In all pre-diagnostic samples, the immunoglobulin (Ig) and/or T-cell receptor (TCR) gene rearrangements were investigated using quantitative real-time PCR. In addition, SNP array and FISH were performed in some cases in order to reveal other aberrations specific to leukemia. To backtrack the preleukemic cells three different approaches were employed - qPCR, FISH and next generation sequencing (NGS). Results Immunoreceptor gene rearrangements were detected in all 5 patients in the diagnostic sample. At least one of the diagnostic rearrangements was found in all preleukemic bone-marrow samples. The levels of positivity differed from 10−1 to 10−6. In 3 patients more than one pre-diagnostic sample was made available for our examination. A surprising dynamics in the size of the leukemic clone was revealed by the investigation. Although a steady increase of blasts was expected, particularly high levels occurred in the first available preleukemic samples (10% and more clonal Ig/TCR positive cells compared to the diagnosis, in 4/5 of patients), followed by remarkable decrease 1 to 3 months before the diagnosis in 3 patients with more than one sample available. This dynamics points to possible immune system interventions during preleukemic phase. In 2 patients NGS (targeted to Ig/TCR gene rearrangements, Adaptive Biotechnologies, Seattle) was applied. The acquired data correlated with the results of qPCR backtracking. In addition, more detailed information was gained about gene rearrangement spectra as well as about possible immunological background of the leukemia progression. In both these patients, the examination revealed a significant fraction of non-malignant γΔ T cell-clone carrying an identical Vg9-Jg1.2 gene rearrangement, which has been reported previously to play an important role in anti-tumour and anti-microbe immune responses. Interestingly, the dynamics of this particular clone seemed to correlate negatively with the leukemic cell levels, pointing out its putative role in tumour surveillance. Consequently, SNP array was performed to define the aberrations acquired, followed by FISH investigation to confirm the above conclusions. While some aberrations were confirmed already in the pre-diagnostic samples (namely ETV6 deletion in the patient with ETV6/RUNX1 positive ALL), others occurred in the diagnostic sample, yet not in the preleukemic cells several months before the diagnosis. Conclusion Preleukemic cells present during the aplastic phase preceding leukemia onset are not just a gradually growing clone. Their specific dynamics has been shown, which supports our previous data acquired during the investigation of secondary leukemias. Furthermore, at least in some cases, this clone indeed should be considered ‘preleukemic’ as it is to undergo at least one more hit or subclonal selection to progress into an active disease. Disclosures: No relevant conflicts of interest to declare.
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Hinkov, Georgi, Plamen Glogov, Vania Kachova, Mira L. Georgieva, Cristian Anghelus, and Аlexandru Liviu Ciuvat. "A methodological approach for monitoring of riparian forests in protected areas on Danube islands." Silva Balcanica 21, no. 2 (2020): 53–69. http://dx.doi.org/10.3897/silvabalcanica.21.e54963.
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In the last decades, invasive plant species have rapidly settled on the islands in the Danube River. This process is closely related to anthropogenic activities, such as felling and cultivation of soil for affor-estation of Euro-American poplar trees throughout the Danube River basin. In this regard, it is im-portant to: (i) determine the speed and scope of invasive vegetation establishment and (ii) determine more precisely the ongoing successional dynamics. Monitoring in permanent plots is needed to track the changes and assist in decision-making processes for the management of protected areas on the islands in the Danube River. The aim of the study is to describe and justify an innovative approach to analyse the dynamic of the invasion species occurrence and development as related to site conditions and management across the islands in the Danube River. The following methodological approach was considered: (1) selection of islands with well-preserved and sufficient in area covered by natural forest vegetation; (2) differentiation of strata by forest type, age and canopy cover; (3) setting up permanent sample plots for long-term monitoring in natural riparian forests.
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Matthiopoulos, Jason, Christopher Field, and Ross MacLeod. "Predicting population change from models based on habitat availability and utilization." Proceedings of the Royal Society B: Biological Sciences 286, no. 1901 (2019): 20182911. http://dx.doi.org/10.1098/rspb.2018.2911.
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The need to understand the impacts of land management for conservation, agriculture and disease prevention are driving demand for new predictive ecology approaches that can reliably forecast future changes in population size. Currently, although the link between habitat composition and animal population dynamics is undisputed, its function has not been quantified in a way that enables accurate prediction of population change in nature. Here, using 12 house sparrow colonies as a proof-of-concept, we apply recent theoretical advances to predict population growth or decline from detailed data on habitat composition and habitat selection. We show, for the first time, that statistical population models using derived covariates constructed from parametric descriptions of habitat composition and habitat selection can explain an impressive 92% of observed population variation. More importantly, they provide excellent predictive power under cross-validation, anticipating 81% of variability in population change. These models may be embedded in readily available generalized linear modelling frameworks, allowing their rapid application to field systems. Furthermore, we use optimization on our sample of sparrow colonies to demonstrate how such models, linking populations to their habitats, permit the design of practical and environmentally sound habitat manipulations for managing populations.
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Marpu, Sreekar B., Brian Leon Kamras, Nooshin MirzaNasiri, et al. "Single-Step Photochemical Formation of Near-Infrared-Absorbing Gold Nanomosaic within PNIPAm Microgels: Candidates for Photothermal Drug Delivery." Nanomaterials 10, no. 7 (2020): 1251. http://dx.doi.org/10.3390/nano10071251.
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This work demonstrates the dynamic potential for tailoring the surface plasmon resonance (SPR), size, and shapes of gold nanoparticles (AuNPs) starting from an Au(I) precursor, chloro(dimethyl sulfide)gold (I) (Au(Me2S)Cl), in lieu of the conventional Au(III) precursor hydrogen tetrachloroaurate (III) hydrate (HAuCl4). Our approach presents a one-step method that permits regulation of an Au(I) precursor to form either visible-absorbing gold nanospheres or near-infrared-window (NIRW)-absorbing anisotropic AuNPs. A collection of shapes is obtained for the NIR-absorbing AuNPs herein, giving rise to spontaneously formed nanomosaic (NIR-absorbing anisotropic gold nanomosaic, NIRAuNM) without a dominant geometry for the tesserae elements that comprise the mosaic. Nonetheless, NIRAuNM exhibited high stability; one test sample remains stable with the same SPR absorption profile 7 years post-synthesis thus far. These NIRAuNM are generated within thermoresponsive poly(N-isopropylacrylamide) (PNIPAm) microgels, without the addition of any growth-assisting surfactants or reducing agents. Our directed-selection methodology is based on the photochemical reduction of a light-, heat-, and water-sensitive Au(I) precursor via a disproportionation mechanism. The NIRAuNM stabilized within the thermoresponsive microgels demonstrates a light-activated size decrease of the microgels. On irradiation with a NIR lamp source, the percent decrease in the size of the microgels loaded with NIRAuNM is at least five times greater compared to the control microgels. The concept of photothermal shrinkage of hybrid microgels is further demonstrated by the release of a model luminescent dye, as a drug release model. The absorbance and emission of the model dye released from the hybrid microgels are over an order of magnitude higher compared to the absorbance and emission of the dye released from the unloaded-control microgels.
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Cuevas-González, María Verónica, Fernando Suaste-Olmos, Alma Graciela García-Calderón, et al. "Expression of MicroRNAs in Periodontal Disease: A Systematic Review." BioMed Research International 2021 (January 19, 2021): 1–6. http://dx.doi.org/10.1155/2021/2069410.
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Introduction. Periodontal disease (PD) is a chronic inflammation of the soft tissues that support the structure of the tooth, and miRNAs are highly dynamic molecules that participate in the regulation of gene expression interfering with multiple genetic targets. The dysregulation of the expression of miRNAs has been associated with different types of pathologies; therefore, they are excellent molecules to be studied as biomarkers. Material and Methods. A search was made in the electronic databases of PubMed, Scopus, and Science Direct. The following key words were used: “microRNAs,” “miRNAs,” “periodontal disease,” “periodontitis,” and “biomarker”; employee independent search strategies with the Boolean operators “OR” and “AND”; a further search of the references of the selected studies was performed to detect potential studies that met the selection criteria. The data recollected from each article were author, country, year of publication, sample size, type of sample used to identify miRNAs, methodology used to identify miRNAs, type of periodontal disease, and miRNAs identified. Results. Of the 13 selected studies, 6 used gingival tissue as a sample for the identification of miRNAs, 3 used gingival fluid, 2 used saliva, 1 used serum, and another used periodontal tissue. Chronic periodontitis was the most studied periodontal disease in 9 of the 13 selected articles; 7 used microarrays as the main technique for the identification of miRNAs. qRT-PCR was the assay choice to validate the identified miRNAs. Conclusion. The main type of periodontal disease on which most studies are focused is chronic periodontitis, with the main miRNAs being hsa-miR-146a, hsa-miR-146b, hsa-miR-155, and hsa-miR-200. This systematic review is one of the first to carry out an analysis of the current role of miRNAs in PD as biomarkers.
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De Andrés, Javier, Beatriz Pariente, Martin Gonzalez-Rodriguez, and Daniel Fernandez Lanvin. "Towards an automatic user profiling system for online information sites." Online Information Review 39, no. 1 (2015): 61–80. http://dx.doi.org/10.1108/oir-06-2014-0134.
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Purpose – The purpose of this paper is to identify demographic differences based on how users interact with web applications. The research is needed to develop future systems able to adapt the representation of online information to the user’s specific needs and preferences improving its usability. The following question guides this quest: is there a direct relationship between age and/or gender and interaction? Design/methodology/approach – GOMS (goals, operators, methods, and selection rules) analysis was used to reduce complex interaction tasks into basic operators like pointing, dragging, typing, etc. An experiment was designed to analyse the user performance in the use of these operators through five complex tasks: point-and-click, drag-and-drop, text selection, text edition and menu selection. The sample comprises 592 individuals which took part in the experiment. The performance was analysed using multivariate regression analysis. User laterality and the the user experience were used as control variables. Findings – The factors studied are significant enough to support user classification. The analysis evidenced that men performed significantly better than women when executing interaction pointing and dragging GOMS’s operators, but no significant differences arose with regard to the performance in the typing operators. Older users performed worse in all the interaction tasks. No significant performance differences were detected between left and right-handed users. Research limitations/implications – The study pretends to lay the ground for developing artificial intelligence-based classification systems (e.g. neural networks, decision trees, etc.) able to detect significant differences in user performance, classifying users according to their age, gender and laterality. Practical implications – This user profiling would drive the organisation, selection and representation of the online information according to the specific preferences and needs of each user. This would allow the design of new personalisation algorithms able to perform dynamic adaptation of user interfaces in order to improve the usability of online information systems. Originality/value – This work extends previous research on user performance under a new approach and improved accuracy. First, it relies on the combined and simultaneous analysis of ageing and gender and the use of user laterality and experience as control variables. Second, the use of the GOMS analysis allowed the design of tests that closely resemble the user interaction in online information systems. Third, the size of the sample used in this analysis is much bigger than those used in previous works, allowing a more thorough data analysis which includes the estimation of an advanced model which is quantile regression.
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Ma, Jichun, and Di Xia. "The use of blue native PAGE in the evaluation of membrane protein aggregation states for crystallization." Journal of Applied Crystallography 41, no. 6 (2008): 1150–60. http://dx.doi.org/10.1107/s0021889808033797.
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Crystallization has long been one of the bottlenecks in obtaining structural information at atomic resolution for membrane proteins. This is largely due to difficulties in obtaining high-quality protein samples. One frequently used indicator of protein quality for successful crystallization is the monodispersity of proteins in solution, which is conventionally obtained by size exclusion chromatography (SEC) or by dynamic light scattering (DLS). Although useful in evaluating the quality of soluble proteins, these methods are not always applicable to membrane proteins either because of the interference from detergent micelles or because of the requirement for large sample quantities. Here, the use of blue native polyacrylamide gel electrophoresis (BN–PAGE) to assess aggregation states of membrane protein samples is reported. A strong correlation is demonstrated between the monodispersity measured by BN–PAGE and the propensity for crystallization of a number of soluble and membrane protein complexes. Moreover, it is shown that there is a direct correspondence between the oligomeric states of proteins as measured by BN–PAGE and those obtained from their crystalline forms. When applied to a membrane protein with unknown structure, BN–PAGE was found to be useful and efficient for selecting well behaved proteins from various constructs and in screening detergents. Comparisons of BN–PAGE with DLS and SEC are provided.
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Yuki, Satoshi, Kentaro Yamazaki, Hiroya Taniguchi, et al. "The nationwide screening project on plasma angiogenesis-related mediators for treatment selection of optimal antiangiogenic inhibitors in metastatic colorectal cancer: GI-SCREEN CRC-Ukit." Journal of Clinical Oncology 36, no. 4_suppl (2018): TPS885. http://dx.doi.org/10.1200/jco.2018.36.4_suppl.tps885.
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TPS885 Background: Antiangiogenic treatments are a proven useful tool to improve clinical outcomes in patients (pts) with metastatic colorectal cancer (mCRC). Recently, higher levels of vascular endothelial growth factor-D (VEGF-D) are a potential predictive biomarker for ramucirumab efficacy on overall and progression-free survival in mCRC (Tabernero J, et al. ESMO 2017). However, there are limited data on mCRC associating the efficacy of antiangiogenic therapy with angiogenesis-related mediators, such as VEGF family members and their receptors, and with dynamic transition among these mediators during clinical courses. In addition, immune-related factors such as interferon gamma (IFNγ) and transforming growth factor β1 (TGFβ1) may be associated with the regulation of angiogenesis. Methods: This prospective longitudinal study aims to investigate the association between plasma angiogenesis-related mediators and clinical outcomes in mCRC. The key eligibility criteria include pts with mCRC who will receive one of the following regimens: first-line chemotherapy plus bevacizumab, first-line chemotherapy plus anti-EGFR antibody (either cetuximab or panitumumab), second-line FOLFIRI plus ramucirumab, second-line FOLFIRI plus aflibercept, or second-line chemotherapy plus bevacizumab. Plasma is collected twice in pairs from all pts pre- and post-treatment. Comprehensive measurements of plasma angiogenesis-related mediators, such as placental growth factor (PlGF), hepatocyte growth factor (HGF), IL-6, IL-8, angiopoietin-2, neuropillin-1, tissue inhibitor of metalloproteinase-1 (TIMP-1), soluble intercellular adhesion molecule-1 (sICAM-1), soluble vascular cell adhesion molecule-1 (sVCAM-1), thrombospondin-2 (TSP-2), osteopontin (OPN), sVEGFR-1, sVEGFR-2, sVEGFR-3, VEGF-A, VEGF-D, as well as key targets associated with immunotherapy such as IFNγ and TGFβ1 are analyzed in parallel by the multiplex assay with Luminex® technology. The target sample size is 1,000. This study was initiated in September 2017. Clinical trial information: UMIN000028616.
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Imamura, Gaku, and Genki Yoshikawa. "Development of a Mobile Device for Odor Identification and Optimization of Its Measurement Protocol Based on the Free-Hand Measurement." Sensors 20, no. 21 (2020): 6190. http://dx.doi.org/10.3390/s20216190.
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Practical applications of machine olfaction have been eagerly awaited. A free-hand measurement, in which a measurement device is manually exposed to sample odors, is expected to be a key technology to realize practical machine olfaction. To implement odor identification systems based on the free-hand measurement, the comprehensive development of a measurement system including hardware, measurement protocols, and data analysis is necessary. In this study, we developed palm-size wireless odor measurement devices equipped with Membrane-type Surface stress Sensors (MSS) and investigated the effect of measurement protocols and feature selection on odor identification. By using the device, we measured vapors of liquids as odor samples through the free-hand measurement in different protocols. From the measurement data obtained with these protocols, datasets of transfer function ratios (TFRs) were created and analyzed by clustering and machine learning classification. It has been revealed that TFRs in the low-frequency range below 1 Hz notably contributed to vapor identification because the frequency components in that range reflect the dynamics of the detection mechanism of MSS. We also showed the optimal measurement protocol for accurate classification. This study has shown a guideline of the free-hand measurement and will contribute to the practical implementation of machine olfaction in society.
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Šotnár, Karol, and Ján Topercer. "Estimating density, population size and dynamics of Common Buzzard (Buteo buteo) in the West Carpathian region by a new method." Slovak Raptor Journal 3, no. 1 (2009): 1–12. http://dx.doi.org/10.2478/v10262-012-0027-1.
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Estimating density, population size and dynamics of Common Buzzard (Buteo buteo) in the West Carpathian region by a new method In the Hornr Ponitrie Region (central Slovakia) during 1991-2001 we conducted a regular survey of Common Buzzard nests. In 2002-2006 our sampling effort increased and within the selected areas we studied buzzard dispersion/distribution, density and population dynamics using a new method of large-scale thorough search for nests with multiple nest check. The method is designed to estimate the dispersion/distribution, density and population size of target species (particularly raptors) at an absolute scale of abundance in large tracts of heterogeneous landscapes for studies of population fluctuations, trophic dynamics, reproductive success, habitat selection and use. It consists of systematic search for nests with extent of several tens of km2 and grain of c. 3000 m2, identifying and positioning the nests, and subsequent 1-3 nest checks during the each of three or more consecutive breeding periods. Further essential features include correct record of nest positions and other variables, combination of nest checks with ringing and marking, proportional sampling in apparently suitable and less suitable areas and proper timing and spacing of nest visits. In 2007 the sampling focused on DSF (Databank of Slovak Fauna) grid square 7377 covering c. 135 km2. We searched 71 km2 in total and estimated the density at 129 pairs/100 km2. Within the district of Prievidza (959 km2) we found 150 active buzzard nests. In 2008 we sampled the grid square 7377 more extensively, including higher altitudes (800-1200 m a. s. l.). Sampling of 82 km2 in total yielded the density estimate of 93 pairs/100 km2. Within the district of Prievidza we found 110 active buzzard nests. The reproductive success over four year period averaged 1.2 fledgling per active nest (n = 310 nests). Our sample enabled us to estimate the minimum population size in the whole grid square 7377 at 130 breeding pairs, i.e. 96 pairs/100 km2. Minimum population size for the whole district of Prievidza can be estimated approximately at 500 breeding pairs (52 pairs/100 km2), c. 350 of which breed in mountain forests, c. 80 in agricultural woodlots, and c. 70 in riparian vegetation. Rough estimate of minimum breeding population in the whole Slovakia is c. 15 000 pairs, i.e. on average 31 pairs/100 km2.