Inpainting images with curvilinear structures propagation

Inpainting images with smooth curvilinear structures interrupted is a challenging problem, because the structures are salient features sensitive to the human vision system and they are not easy to be completed in a visually pleasing way, especially when gaps are large. In this paper, we propose an approach to address this problem. A curve with a desired nice shape is first created to smoothly extend the missing structure from the known to unknown regions. As the curve partitions the unknown region into separate areas, textures can be filled independently into each area. We then adopt a patch-based texture inpainting method enhanced by a novel similarity measurement of patches. After that, very abrupt edges caused by different inpainted colours on their two sides need to be smoothed for natural colour transition across the curve. Experimental results demonstrate the effectiveness of the proposed approach. © 2014 Springer-Verlag Berlin Heidelberg.

Representing images using curvilinear feature driven subdivision surfaces.

This paper presents a subdivision-based vector graphics for image representation and creation. The graphics representation is a subdivision surface defined by a triangular mesh augmented with color attribute at vertices and feature attribute at edges. Special cubic B-splines are proposed to describe curvilinear features of an image. New subdivision rules are then designed accordingly, which are applied to the mesh and the color attribute to define the spatial distribution and piecewise-smoothly varying colors of the image. A sharpness factor is introduced to control the color transition across the curvilinear edges. In addition, an automatic algorithm is developed to convert a raster image into such a vector graphics representation. The algorithm first detects the curvilinear features of the image, then constructs a triangulation based on the curvilinear edges and feature attributes, and finally iteratively optimizes the vertex color attributes and updates the triangulation. Compared with existing vector-based image representations, the proposed representation and algorithm have the following advantages in addition to the common merits (such as editability and scalability): 1) they allow flexible mesh topology and handle images or objects with complicated boundaries or features effectively; 2) they are able to faithfully reconstruct curvilinear features, especially in modeling subtle shading effects around feature curves; and 3) they offer a simple way for the user to create images in a freehand style. The effectiveness of the proposed method has been demonstrated in experiments.

The relationship between ethical leadership and unethical pro-organizational behavior: linear or curvilinear effects?

In this study, we examine the nature of the relationship between ethical leadership and unethical pro-organizational behavior (UPB), defined as unethical behavior conducted by employees with the aim of benefiting their organization, and whether the strength of the relationship differs between subordinates experiencing high and low identification with supervisor. Based on three-wave survey data obtained from 239 public sector employees in China, we find that ethical leadership has an inverted u-shaped (curvilinear) relationship with UPB. As the level of ethical leadership increases from low to moderate, UPB increases; as the level of ethical leadership increases from moderate to high, UPB decreases. Further, we find that the strength of this inverted u-curve relationship differs between subordinates with high and low identification with supervisor. That is to say, the inverted u-shaped relationship between ethical leadership and UPB was stronger when subordinates experienced high levels of identification with supervisor. The theoretical and managerial implications of our findings for understanding how to manage UPB in an organizational context are discussed. © 2012 Springer Science+Business Media Dordrecht.

Curvilinear telomere length dynamics in a squamate reptile

1. The lack of consensus concerning the impact of telomere length (TL) dynamics on survival emphasizes the need for additional studies to evaluate the effect of TL on key life-history processes.
2. Using both cross-sectional and longitudinal data, we therefore explored age-specific TL dynamics in a squamate reptile: the frillneck lizard (Chlamydosaurus kingii).
3. Our cross-sectional analyses revealed that young lizards had short TL, TL increased in medium-aged lizards, but TL decreased in older age cohorts, revealing a curvilinear relationship between TL and frillneck lizard age.
4. Neither our cross-sectional nor our longitudinal analyses revealed any association between TL dynamics and lizard survival.
5. We observed a significant positive relationship between TL and telomerase expression (TE), suggesting that TE is a significant determinant of frillneck lizard TL dynamics.
6. Importantly, our longitudinal analyses revealed a positive relationship between initial TL and telomere attrition rate within individual lizards, that is lizards with short initial telomeres were subjected to reduced telomere attrition rates compared to lizards with long initial TL.
7. Our results strongly suggest that TL and TE dynamics in frillneck lizards is not associated with lizard survival but rather reflect an adaptation to maintain TL above a critical minimum length in order to sustain cellular homeostasis.

Use of geographical information systems as a tool for predicting fish yield in tropical reservoirs : case study on Sri Lankan reservoirs

Use of geographical information systems (GIS) in inland fisheries has hitherto been essentially restricted to site evaluation for aquaculture development and assessment of limnological changes in time and space in individual water bodies. The present GIS study was conducted on the land-use pattern of the catchments of nine reservoirs in Sri Lanka, for which detailed fishery data, viz. yield, fishing intensity, landing size of major constituent species, together with selected limnological data such as conductivity and chlorophyll-a, were available. Potential statistical relationships (linear, curvilinear, exponential and second-order polynomial) of fish yield (FY, in kg ha−1 yr−1) to different land-use patterns, such as forest cover (FC, in km2) and shrub-land (SL, in km2), either singly, or in combination, and/or the ratio of each land type to reservoir area (RA in km2) and reservoir capacity (RC in km3), were explored. Highly significant relationships were evident between FY to the ratio of SL and/or FC+SL to RA and/or RC. Similarly, the above land-use types to RA and RC ratios were significantly related to limnological features of the reservoirs. The relationships of FY to various parameters obtained in this study were much better correlated than those relationships of FY to limnological and biological parameters used in yield prediction in tropical and temperate lacustrine waters previously.

Motor-unit coherence and its relation with synchrony are influenced by training

The purpose of the study was to quantify the strength of motor-unit coherence from the left and right first dorsal interosseous muscles in untrained, skill-trained (musicians), and strength-trained (weightlifters) individuals who had long-term specialized use of their hand muscles. The strength of motor-unit coherence was quantified from a total of 394 motor-unit pairs in 13 subjects using data from a previous study in which differences were found in the strength of motor-unit synchronization depending on training status. In the present study, we found that the strength of motor-unit coherence was significantly greater in the left compared with the right hand of untrained right-handed subjects with the largest differences observed between 21 and 24 Hz. The strength of motor-unit coherence was lower in both hands of skill-trained subjects (21–27 Hz) and the right (skilled) hand of untrained subjects (21–24 Hz), whereas the largest motor-unit coherence was observed in both hands of strength-trained subjects (3–9 and 21–27 Hz). A strong curvilinear association was observed between motor-unit synchronization and the integral of coherence at 10–30 Hz in all motor-unit pairs (r² = 0.77), and was most pronounced in strength-trained subjects (r² = 0.90). Furthermore, this association was accentuated when using synchronization data with broad peaks (>11 ms), suggesting that the 10- to 30-Hz coherence is due to oscillatory activity in indirect branched common inputs. The altered coherence with training may be due to an interaction between cortical inhibition and the number of direct common inputs to motor neurons in skill- or strength-trained hands.

Job stress in the law enforcement sector: comparing the linear, non-linear and interaction effects of working conditions

This study addresses a gap in much of the research involving stress among high-risk occupations by investigating the effects of linear, non-linear and interaction models in a law enforcement organization that has undertaken a series of efficiency-driven organizational reforms. The results of a survey involving 2085 police officers indicated that the demand-control-support model provided good utility in predicting an officer's satisfaction, commitment and well-being. In particular, social support and job control were closely associated with all three outcome variables. Although the demand × control/support interactions were not identified in the data, there was some support for the curvilinear effects of job demands. The results have implications for the organizational conditions that need to be addressed in contemporary policing environments where new public management strategies have had widespread affects on the social and organizational context in which policing takes place.

A clarification of the ERI model : the importance of personality

The present study aimed to investigate the role of personality in the etfort-reward imbalance model along with the construct validity of overcommitment in relation to Type A behaviour. The study sample consisted of 898 operational law enforcement persolllel from a large Australian police service. Factor analysis revealed that the overcommitment construct was psychologically related to, but distinct from, the Type A dimensions achievement striving, impatience-irritability and hostility despite the hypothesised interrelatedness of the measures. Multiple regression analyses including tests for curvilinear effects revealed that the Type A dimensions made a significant improvement to the prediction of employee wellbeing and job satisfaction, The results of the study provide theoretical implications in terms of the augmentation of the effort-reward imbalance model.

Promoting health at work : the relevance of organizational justice

Research focusing on the relationship between organizational justice and health suggests that perceptions of fairness can make significant contributions to employee wellbeing. However studies examining the justice health relationship are only just emerging and there are several areas where further research is required, in particular, the uniqueness of the contributions made by justice and the extent to which the health effects can be explained by linear, non-linear and/or interactional models. The primary aim of the current study was to determine the main, curvilinear and interactive effects of job characteristics and organizational justice perceptions on psychological wellbeing and job satisfaction. Job characteristics were measured using the Demand-Control Support (DCS) model (Karasek & Theorell, 1990), while Colquitt's (2001) four justice dimensions (distributive, procedural, interpersonal and informational) were used to assess organizational justice. Hierarchical regression analyses found that in relation to psychological wellbeing, perceptions of justice did not add to the explanatory power of the DCS model. In contrast, organizational justice did account for unique variance in job satisfaction, the second measure of employee wellbeing. The results supported direct linear relationships between the psychosocial working conditions and the outcome measures. The implications of the results of this study, especially in terms of how working conditions should be managed in order to promote health, are discussed. Notably, the findings from the current study indicate that in addition to traditional job stressors, health promotion strategies should focus on perceptions of organizational justice and their relationships with health.

Promoting employee wellbeing : the relevance of work characteristics and organizational justice

Research focusing on the relationship between organizational justice and health suggests that perceptions of fairness can make significant contributions to employee wellbeing. However, studies examining the justice–health relationship are only just emerging and there are several areas where further research is required, in particular, the uniqueness of the contributions made by justice and the extent to which the health effects can be explained by linear, non-linear and/or interaction models. The primary aim of the current study was to determine the main, curvilinear and interaction effects of work characteristics and organizational justice perceptions on employee wellbeing (as measured by psychological health and job satisfaction). Work characteristics were measured using the demand–control–support (DCS) model (Karasek and Theorell, 1990) and Colquitt's (2001) four justice dimensions (distributive, procedural, interpersonal and informational) assessed organizational justice (Colquitt, 2001). Hierarchical regression analyses found that in relation to psychological health, perceptions of justice added little to the explanatory power of the DCS model. In contrast, organizational justice did account for unique variance in job satisfaction, the second measure of employee wellbeing. The results supported linear relationships between the psychosocial working conditions and the outcome measures. A significant two-way interaction effect (control x support at work) was found for the psychological health outcome and the procedural justice by distributive justice interaction was significant for the job satisfaction outcome. Notably, the findings indicate that in addition to traditional job stressors, health promotion strategies should also address organizational justice.

Photoaffinity labeling of the N-methyltransferase domains of cyclosporin synthetase

The multifunctional polypeptide cyclosporin synthetase (CySyn) remains one of the most complex nonribosomal peptide synthetase described. In this study we used a highly specific photoaffinity labeling procedure with the natural cofactor S-adenosyl-l-methionine (AdoMet), 14C-isotopically labeled at the Sδ methyl group to probe the concerted AdoMet-binding interaction of the N-methyltransferase (N-MTase) centers of CySyn. The binding stoichiometry for the enzyme–AdoMet complex was determined to be 1:7, which is in agreement with inferences made from analysis of the complementary DNA sequence of the simA gene encoding the CySyn polypeptide. The photolabeling of the AdoMet-binding sites displayed homotropic negative cooperativity, characterized by a curvilinear Scatchard plot with upward concavity. Although, the process of N-methyl transfer is not a critical event for peptide elongation, the destabilizing homotropic interactions between N-MTase centers that were observed may represent a mechanism whereby the enzyme preserves the proficiency of the substrate-channeling process of cyclosporin peptide assembly over a broad range of cofactor concentrations. Furthermore, we demonstrated the utility of the photolabeling procedure for tracking the enzyme during purification.

Effect of hydrogen/air flow rates and scan rate on the flame ionisation detection response of phopholipids, and their quantitative and qualitative analysis by Iatroscan (Mark‐6s) TLC‐FID

The combined effect of scan speed, hydrogen and air flow rates on the flame ionization detection (FID) peak response of phospholipid classes has been studied to determine the optimum levels of these parameters. The phospholipid composition of different types of commercial lecithins, as well as lecithins combined with fish oils, has been analyzed by Iatroscan TLC‐FID Mark‐6s under optimized conditions. An air flow rate of 2 L/min, a hydrogen flow rate of 150–160 mL/min, and a scan speed of 30 s/rod seem to be the ideal conditions for scanning phospholipids with complete pyrolysis in the flame in the Mark‐6 model. Increasing the scan speed rapidly decreased the FID response. A hydrogen flow rate as high as 170 mL/min could be used at relatively low air flow rates (&#x003C2 L/min) and the response declined when both air flow rate and hydrogen flow rate increased simultaneously. Both linear and curvilinear relationships had highly significant correlations (p&#x003C0.01) with the sample load. Time course reactions, including the hydrolysis of phosphatidylserine using enzymes, can be successfully monitored by the Iatroscan TLC‐FID Chromarod system.

Predictors of the attitudinal and health outcomes of aged care nurses

This study examines the predictive capacity of the Demand-Control-Support (DCS) model in combination with organizational justice variables on attitudinal- and health-related outcomes for aged care nurses. Multiple regression analyses of aged care nurses (n=168) from a medium to large Australian healthcare organization. The DCS model explains the largest amount of variance across both the attitudinal and health outcomes with 27% of job satisfaction and 44% of organizational commitment, and 33% of psychological distress and 35% of wellbeing, respectively. Additional variance was explained by the justice variables for job satisfaction, organizational commitment and psychological distress. The addition of the organizational justice variables to the DCS model proved to be a valuable step in understanding the work conditions of aged care nurses. The inclusion of curvilinear effects clarified the potentially artefactual nature of certain interaction variables. The results provide practical implications for managers of aged care nurses in developing and maintaining levels of job control, support and fairness, as well as monitoring levels of job demands. The results particularly highlight the importance of the nurses’ supervisor.

Supervisors are central to work characteristics affecting nurse outcomes

Purpose: To examine the predictive capability of the demand-control-support (DCS) model, augmented by organizational justice variables, on attitudinal- and health-related outcomes for nurses caring for elderly patients.

Design: The study is based on a cross-sectional survey design and involved 168 nurses working with elderly patients in facilities of a medium to large Australian organization.

Method: Participants were asked to complete a questionnaire consisting of scales designed for measuring independent (e.g., demand, control, support, organizational justice) and dependent (e.g., job satisfaction, organizational commitment, wellbeing and psychological distress) variables. Multiple regression analyses were undertaken to identify significant predictors of the outcome variables.

Findings: The DCS model explains the largest amount of variance across both the attitudinal and health outcomes with 27% of job satisfaction and 49% of organizational commitment, and 33% of psychological distress and 35% of wellbeing, respectively. Additional variance was explained by the justice variables for job satisfaction (5%), organizational commitment (4%), and psychological distress (23%).

Conclusions: Using organizational justice variables to augment the DCS model was valuable in better understanding the work conditions experienced by nurses caring for elderly patients. Inclusion of curvilinear effects added clarity to the potentially artifactual nature of certain interaction variables.

Clinical Relevance: The results indicated practical implications for managers of nurses caring for elderly patients in terms of developing and maintaining levels of job control, support, and fairness, as well as monitoring levels of job demands. The results particularly show the importance of nurses' immediate supervisors.

Annual variation in the distribution of summer snowdrifts in the Kosciuszko alpine area, Australia, and its effect on the composition and structure of alpine vegetation

Australian alpine ecosystems are expected to diminish in extent as global warming intensifies. Alpine vegetation patterns are influenced by the duration of snow cover including the presence of snowdrifts in summer, but there is little quantitative information on landscape-scale relationships between vegetation patterns and the frequency of occurrence of persistent summer snowdrifts in the Australian alps. We mapped annual changes in summer snowdrifts in the Kosciuszko alpine region, Australia, from Landsat TM images and modelled the frequency of occurrence of persistent summer snowdrifts from long-term records (1954–2003) of winter snow depth. We then compared vegetation composition and structure among four classes that differed in the frequency of occurrence of persistent summer snowdrifts. We found a curvilinear relationship between annual winter snow depth and the area occupied by persistent snowdrifts in the following summer (r²=0.9756). Only 21 ha (0.42% of study area) was predicted to have supported summer snowdrifts in 80% of the past 50 years, while 440 ha supported persistent summer snow in 10% of years. Mean cover and species richness of vascular plants declined significantly, and species composition varied significantly, as the frequency of summer snow persistence increased. Cushion plants and rushes were most abundant where summer snowdrifts occurred most frequently, and shrubs, grasses and sedges were most abundant in areas that did not support snowdrifts in summer. The results demonstrate strong regional relationships between vegetation composition and structure and the frequency of occurrence of persistent summer snowdrifts. Reductions in winter snow depth due to global warming are expected to lead to substantial reductions in the extent of persistent summer snowdrifts. As a consequence, shrubs, grasses and sedges are predicted to expand at the expense of cushion plants and rushes, reducing landscape vegetation diversity. Fortunately, few vascular plant species (e.g. Ranunculus niphophilus) appear to be totally restricted to areas where summer snow occurs most frequently. The results from this study highlight potential indicator species that could be monitored to assess the effects of global warming on Australian alpine environments.