979 resultados para MULTIPLE SCALES
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Costus stenophyllus or bamboo costus, despite its high ornamental potential, is still little known in the cut flower and ornamental plant market. The bamboo costus is a spiral ginger admired for its beautiful stems that are lined with brown colored alternating bands. This costus has rather straight and upright stems. Conical red inflorescences, which resemble the head of a snake, emerge from the base of the plants. The flowers are light yellow and emerge between the red scales on the rather long-lasting, attractive inflorescences. This study was carried out to evaluate the possibility of using these species as a garden plant, cut flower and cut stem. Thus, the characterization was made based on 28 characters of the plant, the leaves, the flower stem, the flowers, as well as season blooming characteristics and flower postharvest longevity.
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Evaluations of measurement invariance provide essential construct validity evidence. However, the quality of such evidence is partly dependent upon the validity of the resulting statistical conclusions. The presence of Type I or Type II errors can render measurement invariance conclusions meaningless. The purpose of this study was to determine the effects of categorization and censoring on the behavior of the chi-square/likelihood ratio test statistic and two alternative fit indices (CFI and RMSEA) under the context of evaluating measurement invariance. Monte Carlo simulation was used to examine Type I error and power rates for the (a) overall test statistic/fit indices, and (b) change in test statistic/fit indices. Data were generated according to a multiple-group single-factor CFA model across 40 conditions that varied by sample size, strength of item factor loadings, and categorization thresholds. Seven different combinations of model estimators (ML, Yuan-Bentler scaled ML, and WLSMV) and specified measurement scales (continuous, censored, and categorical) were used to analyze each of the simulation conditions. As hypothesized, non-normality increased Type I error rates for the continuous scale of measurement and did not affect error rates for the categorical scale of measurement. Maximum likelihood estimation combined with a categorical scale of measurement resulted in more correct statistical conclusions than the other analysis combinations. For the continuous and censored scales of measurement, the Yuan-Bentler scaled ML resulted in more correct conclusions than normal-theory ML. The censored measurement scale did not offer any advantages over the continuous measurement scale. Comparing across fit statistics and indices, the chi-square-based test statistics were preferred over the alternative fit indices, and ΔRMSEA was preferred over ΔCFI. Results from this study should be used to inform the modeling decisions of applied researchers. However, no single analysis combination can be recommended for all situations. Therefore, it is essential that researchers consider the context and purpose of their analyses.
Generalizing the dynamic field theory of spatial cognition across real and developmental time scales
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Within cognitive neuroscience, computational models are designed to provide insights into the organization of behavior while adhering to neural principles. These models should provide sufficient specificity to generate novel predictions while maintaining the generality needed to capture behavior across tasks and/or time scales. This paper presents one such model, the Dynamic Field Theory (DFT) of spatial cognition, showing new simulations that provide a demonstration proof that the theory generalizes across developmental changes in performance in four tasks—the Piagetian A-not-B task, a sandbox version of the A-not-B task, a canonical spatial recall task, and a position discrimination task. Model simulations demonstrate that the DFT can accomplish both specificity—generating novel, testable predictions—and generality—spanning multiple tasks across development with a relatively simple developmental hypothesis. Critically, the DFT achieves generality across tasks and time scales with no modification to its basic structure and with a strong commitment to neural principles. The only change necessary to capture development in the model was an increase in the precision of the tuning of receptive fields as well as an increase in the precision of local excitatory interactions among neurons in the model. These small quantitative changes were sufficient to move the model through a set of quantitative and qualitative behavioral changes that span the age range from 8 months to 6 years and into adulthood. We conclude by considering how the DFT is positioned in the literature, the challenges on the horizon for our framework, and how a dynamic field approach can yield new insights into development from a computational cognitive neuroscience perspective.
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This study’s purpose was to determine if efficient measures could be created to assess multiple problematic behaviors identified in youth who were sexually abused and in treatment. Because of the lack of easily administered brief instruments that assess multiple domains of interest in this population, complementary parent and child assessment measures were developed. The Weekly Problems Scale–Child Version (WPSC) and the Weekly Problems Scale–Parent Version (WPS-P) were created to monitor the weekly progress of the child and family in treatment and focus specifically on common areas of difficulties in this population. Exploratory factor analysis was conducted to assist in identifying the number of underlying dimensions in the scales. Results indicate that the WPS-C and WPS-P demonstrate adequate internal consistency, temporal stability, and construct validity. The WPS-C and WPSP display significant promise as research and clinical assessment tools for use with youth who are sexually abused and their nonoffending parents in treatment.
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Chemical and biological sensor technologies have advanced rapidly in the past five years. Sensors that require low power and operate for multiple years are now available for oxygen, nitrate, and a variety of bio-optical properties that serve as proxies for important components of the carbon cycle (e.g., particulate organic carbon). These sensors have all been deployed successfully for long periods, in some cases more than three years, on platforms such as profiling floats or gliders. Technologies for pH, pCO(2), and particulate inorganic carbon are maturing rapidly as well. These sensors could serve as the enabling technology for a global biogeochemical observing system that might operate on a scale comparable to the current Argo array. Here, we review the scientific motivation and the prospects for a global observing system for ocean biogeochemistry.
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A 272-ha grove of dominant Microberlinia bisulcata (Caesalpinioideae) adult trees greater than or equal to 50 cm stem diameter was mapped in its entirety in the southern part of Korup National Park, Cameroon. The approach used an earlier-established 82.5-ha permanent plot with a new surrounding 50-m grid of transect lines. Tree diameters were available from the plot but trees on the grid were recorded as being greater than or equal to 50 cm. The grove consisted of 1028 trees in 2000. Other species occurred within the grove. including the associated subdominants Tetraberlinia bifoliolata and T. korupensis. Microberlinia bisulcata becomes adult at a stein diameter of c. 50 cm and at an estimated age of 50 y. Three oval-shaped subgroves with dimensions c. 8 50 in x 13 50 in (90 ha) were defined. For two of them (within the plot) tree diameters were available. Subgroves differed in their scales and intensities of spatial tree patterns, and in their size frequency distributions, these suggesting differing past dynamics. The modal scale of clumping was 40-50 m. Seed dispersal by pod ejection (to c. 50 in) was evident from the semi-circles of trees at the grove's edge and from the many internal circles (100-200 m diameter). The grove has the capacity. therefore, to increase at c. 100 m per century. To form its present extent and structure. it is inferred that it expanded and infilled from a possibly smaller area of lower adult-tree density. This possibly happened in three waves of recruitment, each one determined by a period of several intense disturbances. Climate records for Africa show that 1740-50 and 1820-30 were periods of drought, and that 1870-1895 was also regionally very dry. Canopy openings allow the light-demanding and fast-growing ectomycorrhizal M. bisulcata to establish, but successive releases are thought to be required to achieve effective recruitment. Nevertheless, in the last 50 y there were no major events and recruitment in the grove was very poor. This present study leads to a new hypothesis of the role of periods of multiple extreme events being the driving factor for the population dynamics of many large African tree species such as M. bisulcata.
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The aim of this study was to analyse the effects of climatic factors (i.e. monthly mean temperature and total precipitation) on radial growth (earlywood width, latewood width, and total ringwidth) and on latewood stable carbon isotope composition in a pedunculate oak (Quercus robur L) stand in northeastern Hungary. Earlywood widths showed the weakest common variance and lack of statistically significant relationship to monthly precipitation and temperature. Latewood width showed the strongest common chronological signal. Correlation analysis with the monthly climate series pointed out the strongest positive/negative correlation with June precipitation for latewood width/stable carbon isotope ratio. These parameters shared the strongest climatic response also for seasonal scale since the highest correlation coefficients, 0.49 and -0.62 for latewood width and stable carbon isotope ratio, respectively, were obtained for both with a 10-month precipitation total (from previous November to current August of the growing season). A combined parameter, derived as difference between latewood width and stable carbon isotope indices showed improved statistical relationship compared to the hydroclimatic calibration target both for local and regional spatial scales. Spatial correlation analysis indicated that the hydroclimatic signal encoded in these moisture sensitive tree-ring parameters from Bakta Forest is expected to be representative for the northeastern Carpathians and for the large part of the Great Hungarian Plain. In addition, the hydroclimatic signal of latewood width chronology was compared to three independent records. Results showed that neither the strength nor the rank of the similarity of the local hydroclimate signals were stable throughout the past two centuries. Future palaeo(hydro)climatological efforts targeting the Carpathian(-Balkan) region are recommended to track carefully the spatial domains for which a given, local, proxy-derived hydroclimate reconstruction might provide useful information.
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During Leg 178, multiple advanced piston corer holes were drilled at four sites (1095, 1096, 1098, and 1099). Cores from the holes were correlated on board to produce composite depths and optimal spliced sections, but the time limitations aboard ship caused these to be preliminary. Recomputed composite depths for Sites 1098 and 1099 in Palmer Deep are reported elsewhere in this volume (doi:10.2973/odp.proc.sr.178.2002). This paper reports recomputed composite depths and spliced sections for Sites 1095 and 1096, located on a sediment drift on the continental rise of the Pacific margin of the Antarctic Peninsula. Limits on the validity of the spliced sections arise from limited multiple coverage and possibly from the effects of ocean swell.
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Multiple copies of Cretaceous black shales extending from the early Cenomanian to the end of the Santonian were recovered at five sites on Demerara Rise during Leg 207 of the Ocean Drilling Program. These sediments are primarily composed of laminated organic-rich claystones interbedded with coarser, lightly laminated foraminferal-bearing packstones and wackestones. The black shales represent the local expression of widespread organic-rich sedimentation in the Atlantic during the mid-Cretaceous. However, incomplete recovery prevented construction of continuous composite sections, resulting in uncertainties concerning the correct stratigraphic placement of individual cores. By combining high-resolution measurements of bulk density collected shipboard on the multisensor track with continuous downhole measurements of formation resistivity using the Formation MicroScanner, an equivalent logging depth scale was constructed for black shales recovered from Sites 1258, 1260, and 1261. The integrated depths approach centimeter-scale resolution and are supported by comparisons of coarser resolution natural gamma ray emissions collected on cores and through downhole logging operations. The new depths highlight the extent of both intra- and intercore gaps and provide an opportunity to further constrain temporal and spatial paleoceanographic changes captured in proxy records from these sediments.
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Neighbourhood representation and scale used to measure the built environment have been treated in many ways. However, it is anything but clear what representation of neighbourhood is the most feasible in the existing literature. This paper presents an exhaustive analysis of built environment attributes through three spatial scales. For this purpose multiple data sources are integrated, and a set of 943 observations is analysed. This paper simultaneously analyses the influence of two methodological issues in the study of the relationship between built environment and travel behaviour: (1) detailed representation of neighbourhood by testing different spatial scales; (2) the influence of unobserved individual sensitivity to built environment attributes. The results show that different spatial scales of built environment attributes produce different results. Hence, it is important to produce local and regional transport measures, according to geographical scale. Additionally, the results show significant sensitivity to built environment attributes depending on place of residence. This effect, called residential sorting, acquires different magnitudes depending on the geographical scale used to measure the built environment attributes. Spatial scales risk to the stability of model results. Hence, transportation modellers and planners must take into account both effects of self-selection and spatial scales.
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The Actively Heated Fiber Optic (AHFO) method is shown to be capable of measuring soil water content several times per hour at 0.25 m spacing along cables of multiple kilometers in length. AHFO is based on distributed temperature sensing (DTS) observation of the heating and cooling of a buried fiber-optic cable resulting from an electrical impulse of energy delivered from the steel cable jacket. The results presented were collected from 750 m of cable buried in three 240 m colocated transects at 30, 60, and 90 cm depths in an agricultural field under center pivot irrigation. The calibration curve relating soil water content to the thermal response of the soil to a heat pulse of 10 W m−1 for 1 min duration was developed in the lab. This calibration was found applicable to the 30 and 60 cm depth cables, while the 90 cm depth cable illustrated the challenges presented by soil heterogeneity for this technique. This method was used to map with high resolution the variability of soil water content and fluxes induced by the nonuniformity of water application at the surface.
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This mixed method study aimed to redress the gap in the literature on academic service-learning partnerships, especially in Eastern settings. It utilized Enos and Morton's (2003) theoretical framework to explore these partnerships at the American University in Cairo (AUC). Seventy-nine community partners, administrators, faculty members, and students from a diverse range of age, citizenship, racial, educational, and professional backgrounds participated in the study. Qualitative interviews were conducted with members of these four groups, and a survey with both close-ended and open-ended questions administered to students yielded 61 responses. Qualitative analyses revealed that the primary motivators for partners' engagement in service-learning partnerships included contributing to the community, enhancing students' learning and growth, and achieving the civic mission of the University. These partnerships were characterized by short-term relationships with partners' aspiring to progress toward long-term commitments. The challenges to these partnerships included issues pertaining to the institution, partnering organizations, culture, politics, pedagogy, students, and faculty members. Key strategies for improving these partnerships included institutionalizing service-learning in the University and cultivating an institutional culture supportive of community engagement. Quantitative analyses showed statistically significant relationships between students' scores on the Community Awareness and Interpersonal Effectiveness scales and their overall participation in community service activities inside and outside the classroom, as well as a statistically significant difference between their scores on the Community Awareness scale and department offering service-learning courses. The study's outcomes underscore the role of the local culture in shaping service-learning partnerships, as well as the role of both curricular and extracurricular activities in boosting students' awareness of their community and interpersonal effectiveness. Cultivating a culture of community engagement and building support mechanisms for engaged scholarship are among the critical steps required by public policy-makers in Egypt to promote service-learning in Egyptian higher education. Institutionalizing service-learning partnerships at AUC and enhancing the visibility of these partnerships on campus and in the community are essential to the future growth of these collaborations. Future studies should explore factors affecting community partners' satisfaction with these partnerships, top-down and bottom-up support to service-learning, the value of reflection to faculty members, and the influence of students' economic backgrounds on their involvement in service-learning partnerships.
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Previous research measuring various biosocial factors such as age, sex, and marital status has found them to be essentially unrelated to measures of psychological health. Recent empirical studies have revealed that personality constructs may be more significant than demographic variables in the prediction of psychological well-being. The present study assessed the personality constructs of masculinity and femininity and hypothesized that the Gender-Masculine ( GM) scale of the MMPI-2 would be more effective than the Gender-Feminine (GF) scale in predicting psychological well-being. This hypothesis stems from previous research that has indicated the dominance of the masculinity model. It is suggested that previous research supporting androgyny as a primary indicator of well-being was influenced by the masculinity component of this gender orientation. One hundred and seventy-seven psychiatric patients from Australia (N = 107) and Singapore ( N 5 70) completed the MMPI-2. Hierarchical multiple regression revealed significantly stronger masculinity effects, with significance achieved on measures of ego strength and low self-esteem. No significant relationship between psychological well-being and the GF variable was found. Similarly, androgyny did not add any further variance to the model when masculinity was controlled for. Overall, the results are consistent with an interpretation that GM is a better correlate of psychological well-being as compared to the GF scale.
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In our recent work in different bioreactors up to 2.5L in scale, we have successfully cultured hMSCs using the minimum agitator speed required for complete microcarrier suspension, N
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Network Virtualization is a key technology for the Future Internet, allowing the deployment of multiple independent virtual networks that use resources of the same basic infrastructure. An important challenge in the dynamic provision of virtual networks resides in the optimal allocation of physical resources (nodes and links) to requirements of virtual networks. This problem is known as Virtual Network Embedding (VNE). For the resolution of this problem, previous research has focused on designing algorithms based on the optimization of a single objective. On the contrary, in this work we present a multi-objective algorithm, called VNE-MO-ILP, for solving dynamic VNE problem, which calculates an approximation of the Pareto Front considering simultaneously resource utilization and load balancing. Experimental results show evidences that the proposed algorithm is better or at least comparable to a state-of-the-art algorithm. Two performance metrics were simultaneously evaluated: (i) Virtual Network Request Acceptance Ratio and (ii) Revenue/Cost Relation. The size of test networks used in the experiments shows that the proposed algorithm scales well in execution times, for networks of 84 nodes