Higher Hierarchical Levels Research Articles

Hierarchical Supramolecular Cross-Linking of Polymers for Biomimetic Fracture Energy Dissipating Sacrificial Bonds and Defect Tolerance under Mechanical Loading.

Biological structural materials offer fascinating models how to synergistically increase the solid-state defect tolerance, toughness, and strength using nanocomposite structures by incorporating different levels of supramolecular sacrificial bonds to dissipate fracture energy. Inspired thereof, we show how to turn a commodity acrylate polymer, characteristically showing a brittle solid state fracture, to become defect tolerant manifesting noncatastrophic crack propagation by incorporation of different levels of fracture energy dissipating supramolecular interactions. Therein, poly(2-hydroxyethyl methacrylate) (pHEMA) is a feasible model polymer showing brittle solid state fracture in spite of a high maximum strain and clear yielding, where the weak hydroxyl group mediated hydrogen bonds do not suffice to dissipate fracture energy. We provide the next level stronger supramolecular interactions toward solid-state networks by postfunctionalizing a minor part of the HEMA repeat units using 2-ureido-4[1H]-pyrimidinone (UPy), capable of forming four strong parallel hydrogen bonds. Interestingly, such a polymer, denoted here as p(HEMA-co-UPyMA), shows toughening by suppressed catastrophic crack propagation, even if the strength and stiffness are synergistically increased. At the still higher hierarchical level, colloidal level cross-linking using oxidized carbon nanotubes with hydrogen bonding surface decorations, including UPy, COOH, and OH groups, leads to further increased stiffness and ultimate strength, still leading to suppressed catastrophic crack propagation. The findings suggest to incorporate a hierarchy of supramolecular groups of different interactions strengths upon pursuing toward biomimetic toughening.

Tracking Control for Mobile Robots Considering the Dynamics of All Their Subsystems: Experimental Implementation

The trajectory tracking task in a wheeled mobile robot (WMR) is solved by proposing a three-level hierarchical controller that considers the mathematical model of the mechanical structure (differential drive WMR), actuators (DC motors), and power stage (DC/DC Buck power converters). The highest hierarchical level is a kinematic control for the mechanical structure; the medium level includes two controllers based on differential flatness for the actuators; and the lowest hierarchical level consists of two average controllers also based on differential flatness for the power stage. In order to experimentally validate the feasibility of the proposed control scheme, the hierarchical controller is implemented via a Σ–Δ-modulator in a differential drive WMR prototype that we have built. Such an implementation is achieved by using MATLAB-Simulink and the real-time interface ControlDesk together with a DS1104 board. The experimental results show the effectiveness and robustness of the proposed control scheme.

Satisfaction of the Service Provider with the Organization of the Timely Cervical Cancer Detection Program

Cervical cancer is a priority health problem in Mexico. The objective of this work was to know the degree of satisfaction of the service provider with the organization of the program of Timely Detection of Cervical Cancer, specifically in taking of the cervical cytology. The study design was observational, transversal and prospective conducted from January to May 2015 in Jurisdiction 1 of the Health Services of San Luis Potosí, Mexico, in 20 health centers. Participants were 87 service providers whose function is to take cervical cytology (Pap smears). A 32-question questionnaire was applied, with Likert scale with 5 levels of response: 1 (dissatisfied), 2 (little satisfied), 3 (indifferent), 4 (satisfied) and 5 (very satisfied). The score range was 32 points (minimum job satisfaction) up to 160 points (Maximum job satisfaction). We analyzed 2 dimensions: 1) intrinsic factors that have to do with motivation and professional recognition, and 2) extrinsic factors related to infrastructure, materials, remuneration and labor policies. Each factor consisted of four categories. Descriptive statistics and linear correlation of Pearson were applied for the analysis of data. Participants signed an informed consent letter. Of 4 categories, in the intrinsic dimension, the one with the highest percentage of satisfaction was “delegation of activities” with 28.8%. In the extrinsic dimension, the category with the highest percentage of satisfaction was “infrastructure and materials” with 49.4%; while satisfaction increase in intrinsic dimensions also does in extrinsic dimensions, such correlations are significant (p < 0.05), except between delegation of activities and remuneration (r = 0.074 and p = 0.497). The higher hierarchical level, the men, the bachelor academic level and older people showed the highest level of satisfaction.

Vantagens e limitações dos registros nacionais de artroplastias. A necessidade de registros multicêntricos: o Rempro‐SBQ

While the value of national arthroplasty registries (NAR) for quality improvement in total hip arthroplasty (THA) has already been widely reported, some methodological limitations associated with observational epidemiological studies that may interfere with the assessment of safety and efficacy of prosthetic implants have recently been described in the literature.Among the main limitations of NAR, the need for at least 80% compliance of all health institutions covered by the registry is emphasized; completeness equal or greater than 90% of all THA performed; restricted data collection; use of revision surgery as the sole criterion for outcome; and the inability of establishing a definite causal link with prosthetic dysfunction.The present article evaluates the advantages and limitations of NAR, in the light of current knowledge, which point to the need for a broader data collection and the use of more structured criteria for defining outcomes.In this scenario, the authors describe of idealization, conceptual and operational structure, and the project of implantation and implementation of a multicenter registry model, called Rempro‐SBQ, which includes healthcare institutions already linked to the Brazilian Hip Society (Sociedade Brasileira de Quadril [SBQ]). This partnership enables the collection of more reliable and comprehensive data at a higher hierarchical level, with a significant reduction in maintenance and financing costs. The quality improvement actions supported by SBQ may enhance its effectiveness and stimulate greater adherence for collecting, storing, interpreting, and disseminating information (feedback).

My cattle and your park: codesigning a role-playing game with rural communities to promote multistakeholder dialogue at the edge of protected areas

Protected areas are often burdened with conflicts between environmental managers and neighboring rural communities. Unsuccessful top-down approaches for conservation may be replaced by alternative forms of systemic management involving local actors in the design and implementation of conservation management. Although theoretically sound and appealing, the involvement of local residents in the management of protected areas is often impaired in practice by scale mismatches, conflicting values and interests, power imbalance, and a lack of trust among actors. In this paper, we describe a process initiated in Zimbabwe to create a fair and balanced locally designed arena where local communities and protected area managers may collaborate to produce effective management plans. Adopting the Companion Modeling approach, we conducted a participatory modeling experiment to codesign a role-playing game that simulates the interactions between farming activities, livestock herding practices, and wildlife in a virtual landscape reproducing local social–ecological dynamics. After 18 months of intensive ethnographical fieldwork to gain knowledge and legitimacy, we spent one year codesigning the first version of the game with a group of volunteer villagers. The game, called Kulayijana (teaching each other), was tested and validated by other members of the rural communities and subsequently presented to protected area managers. We show how this approach allowed the negotiation of uncertainties and their inclusion in a model that constitutes a shared representation of farmers' interactions with the protected area. We emphasize the fact that working with marginalized actors first increased participation, appropriation, and confidence of rural communities to engage in a multistakeholder debate, thus reducing power imbalance among actors. We conclude by discussing the next phase of our work: the necessary involvement of conservation actors in the Kulayijana team, and the implementation of Kulayijana with higher hierarchical levels. (Resume d'auteur)

Advantages and limitations of national arthroplasty registries. The need for multicenter registries: the Rempro-SBQ

While the value of national arthroplasty registries (NAR) for quality improvement in total hip arthroplasty (THA) has already been widely reported, some methodological limitations associated with observational epidemiological studies that may interfere with the assessment of safety and efficacy of prosthetic implants have recently been described in the literature.Among the main limitations of NAR, the need for at least 80% compliance of all health institutions covered by the registry is emphasized; completeness equal or greater than 90% of all THA performed; restricted data collection; use of revision surgery as the sole criterion for outcome; and the inability of establishing a definite causal link with prosthetic dysfunction.The present article evaluates the advantages and limitations of NAR, in the light of current knowledge, which point to the need for a broader data collection and the use of more structured criteria for defining outcomes.In this scenario, the authors describe of idealization, conceptual and operational structure, and the project of implantation and implementation of a multicenter registry model, called Rempro-SBQ, which includes healthcare institutions already linked to the Brazilian Hip Society (Sociedade Brasileira de Quadril [SBQ]). This partnership enables the collection of more reliable and comprehensive data at a higher hierarchical level, with a significant reduction in maintenance and financing costs. The quality improvement actions supported by SBQ may enhance its effectiveness and stimulate greater adherence for collecting, storing, interpreting, and disseminating information (feedback).

Tracking system design for unstable impulse processes in hierarchical cognitive maps of complex systems

The problem of the tracking control in cognitive maps of hierarchical complex systems is considered. Free motion dynamics of a certain hierarchical level is described by an unstable impulse process in a cognitive map. The master control formed on the higher hierarchical level has the step form. The reference model for the characteristic polynomial of the "set point – control error" channel in a closed-loop system is introduced. The control law allowing cognitive map’s output coordinates to track master control changes is found. As an example, we consider the control of commercial bank’s cognitive map of a certain hierarchical level of a banking system. The simulation demonstrates effectiveness of the proposed method.

A Web Based Decision Support System for Intermodal Port and Dry Port Facilities

This paper presents a Web-based Decision Support System (Web-DSS) that was designed and developed to support and provide suggestions on the procedures taking place between a port and a dry port, which have to collaborate, work concurrently and optimize their joint operation. The system operates at the highest hierarchical level supervising a number of different components dealing with three different time scale horizons so as to provide assistance at operational, tactical and strategic level. The Web-based DSS coordinates and integrates the subsystems operating at lower levels and it interfaces with all the involved actors: customers, suppliers, relevant authorities so as to receive all the necessary information to come up with “optimal” suggestions and decisions. In this paper, the overall architecture is presented and the individual modules are described.

Effect of landscape context on fish metacommunity structuring in stream networks

SummaryThe metacommunity framework has shed light upon the significance of local and regional processes in shaping ecological communities. However, our knowledge is limited how landscape context (i.e. type and positioning of habitats) influences the structuring of metacommunities.We examined the role of environmental selection (niche‐based species sorting), dispersal and drift (i.e. stochastic changes in species abundance) mechanisms on the structuring of fish metacommunities in riverscapes. We used a hierarchical design and examined metacommunity structuring (i) in individual running water habitat types, namely highland streams, lowland streams, highland rivers and lowland rivers; (ii) in landscape types, where patterns in highland and in lowland types were examined separately and (iii) at the level of the whole riverscape, where samples from all running water types were pooled. Elements of metacommunity structure (EMS) analysis, community–environmental relationships in redundancy analysis, and decay of community similarity with distance (distance decay) complemented with partial Mantel tests were used to reveal the mechanisms behind the observed patterns.Both theEMSframework and community–environment relationships revealed the prevalent role of selection (niche‐based species sorting mechanisms) on fish metacommunity structuring, although stochastic variability also influenced the results. Metacommunity structures reflecting niche‐based mechanisms (Clementsian or quasi‐Clementsian) were observed at higher hierarchical levels (i.e. at the riverscape and the landscape type levels), while quasi‐Clementsian or random patterns were found within single running water types.Distance decay relationships indicated that dispersal limitation did not clearly affect metacommunity structuring in any combination of running water types. Partial Mantel tests showed that some part of the variation in distance decay could be explained by the correlation between environmental variables and fish assemblage structure in some habitat types, which further suggests the importance of niche‐based mechanisms in metacommunity structuring.Our study shows that different metacommunity structures can arise in a hierarchy of habitat types in riverscapes, and niche‐based species sorting mechanisms are more influential in their structuring than dispersal ones. Landscape classifications are useful for a better understanding of the structuring of metacommunities in both the freshwater and terrestrial realms.

Divergent Coordination Chemistry: Parallel Synthesis of [2×2] Iron(II) Grid-Complex Tauto-Conformers.

The coordination of iron(II) ions by a homoditopic ligand L with two tridentate chelates leads to the tautomerism‐driven emergence of complexity, with isomeric tetramers and trimers as the coordination products. The structures of the two dominant [FeII 4 L 4]8+ complexes were determined by X‐ray diffraction, and the distinctness of the products was confirmed by ion‐mobility mass spectrometry. Moreover, these two isomers display contrasting magnetic properties (FeII spin crossover vs. a blocked FeII high‐spin state). These results demonstrate how the coordination of a metal ion to a ligand that can undergo tautomerization can increase, at a higher hierarchical level, complexity, here expressed by the formation of isomeric molecular assemblies with distinct physical properties. Such results are of importance for improving our understanding of the emergence of complexity in chemistry and biology.

Mechanical behavior of enamel rods under micro-compression

Exploring the structural strategies behind the optimized mechanical performance of hierarchical materials has been a focal point of extensive research over the past decades. Dental enamel is one such natural material, comprising a complicated hierarchical structure with a high level of mineral content. Bundles of hydroxyapatite nanofibers (level-1) Ø: 50nm form enamel rods (level-2) Ø: 5µm, which constitute bands (level-3) Ø: 50µm. While a number of studies in the last decade using advanced fracture mechanical methods have revealed an increasing trend in the fracture toughness of enamel with each additional level of hierarchy, there is still no general agreement on how hierarchical structuring affects the stiffness and strength of enamel. In this study, we identified the stiffness and strength values of the isolated rods (level-2) via micro-compression. The rods were tested in three different orientations with respect to the loading direction: parallel, perpendicular and oblique. The highest stress level withstood before catastrophic fracture was observed to be ~1500MPa in perpendicular orientation. In the oblique loading, the specimens failed by shearing and exhibited a damage-tolerant deformation behavior, which was attributed to the conjugation spots identified between the rods and interrod sheets. The elastic modulus was ~60GPa on average and similar in all orientations. The isotropy in stiffness was attributed to the mineral contacts residing between rods. This was verified by an analytical model derived for level-1 and extended over higher hierarchical levels. The experimental results obtained at level-2 were comparable to the compressive strength and stiffness values reported for level-1 and bulk enamel in the literature. In general, our results suggest that hierarchy has only a minor influence on the compressive properties of enamel.

Alternativas Latino-Americanas para Crise Ambiental Gestadas Além do Capitalismo

This study aims to analyze some proposals contained in the laws Latin American for the treatment of nature and which opposes the capitalist mode of production, currently hegemonic, which have a destructive logic of reproduction, incessant expansion produced serious environmental crisis in which the planet is immersed. The constitution of Ecuador and the Law of Mother Earth in Bolivia, constitute revolutionary experiences in seeking a new format for sustainability, considering the environmental complexity, treats the earth as a living being and fundamental to the maintenance of the human existence, recreating the ethics of responsibility in the relationship with the environment. The nature so conceived has rights that must be protected on the basis of in dubio pro environment, placing environmental concerns at a higher hierarchical level, besides creating several mechanisms to ensure that alternative mode of living, there called good life, which distinguished contemporary societies live better on capitalist liberal guidance.

Exploring intraspecific climatic niche conservatism to better understand species invasion: the case of Trachemys dorbigni (Testudines, Emydidae)

Niche conservatism at distinct levels of biological hierarchy is still a highly debated topic in ecology. The general evaluation of niche shifts is mainly addressed to species level, with few explorations at lower or higher hierarchical levels. The freshwater turtle Trachemys dorbigni (Black-Bellied Slider) has recently been divided into two subspecies that occur in very different climatic conditions and is also considered to be an invasive species in parts of eastern and southeastern regions in Brazil. Here, we aimed to explore the effects of evaluating climatic niche conservatism at subspecific levels during the invasive process of T. dorbigni. We evaluated niche conservatism based on similarity (whether niches are more similar than expected by chance) and also measured expansion, stability, and unfilling in the invaded niche. We found that the climatic niches of the T. dorbigni recognized subspecies are very different, but when they are merged, the environmental condition created is more similar to the invasive niche of the subspecies T. dorbigni dorbigni. We also found consistent evidence of niche conservatism in invaded areas, which enables the effective use of ecological niche models to forecast T. dorbigni dorbigni invasion in other geographic regions.

Reviewing a Friend - The Role of Social Ties in Review Work in Auditing

Hierarchically structured review work is a pervasive element in many professional work settings, including auditing. However, little is known about social factors underlying the pairing of reviewers and reviewees and their impact on quality. The German auditing setting provides a unique opportunity to empirically observe review work at the highest hierarchical level. We investigate the role of social ties in the pairing of concurring auditor (reviewer) and lead auditor (reviewee). We find that the presence of social ties between the concurring auditor and the lead auditor resulting from local affinity, i.e., having the same dialect and working in the same office, makes it more likely for the auditors to form pairs. In contrast, the presence of educational affinity, i.e., having a similar level of audit experience and the same field of study, makes it less likely for auditors to form pairs. Using an instrumental variable approach to control for selection effects, we find that pairs sharing a local background provide lower audit quality, whereas pairs sharing an educational background provide higher audit quality. Our findings should be of interest to regulators, audit firms, audit clients and investors.

“Want to” Versus “Have to”: Intrinsic and Extrinsic Motivators as Predictors of Compliance Behavior Intention

“Worthless,” “money burning,” or “black holes” is how media and professionals describe compliance practices today. Practitioners are unenthusiastic about control systems, codes of conducts, and systems for compliance management that are increasing in volume but not in effectiveness. In order to help practitioners clarify what actually makes employees comply with their compliance program, this study examines intrinsic and extrinsic motivators of 119 employees from procurement and sales. We contribute to the existing motivation literature, testing the self-determination theory in low and high hierarchical levels. Our findings show that intrinsic motivators are more strongly and positively related to compliance intention on higher hierarchical levels than the lower ones. However, employees from higher hierarchies show overall less compliance intention than employees from lower hierarchies. © 2015 The Authors. Human Resource Management published by Wiley Periodicals, Inc.

Chasing the Dragon –An Overview of Heroin Trafficking

There are many problems encountered during the attempt to tackle the heroin trade on a global level. Afghanistan is largely responsible for the production of heroin, providing a global distribution amount of 75%. The trafficking of heroin has continued using the traditional Balkan and Northern routes, however due to the increase in intelligence and border force controls, alternative routes are being established. This demonstrates a key issue being faced by law enforcement agencies. The development in strategies and techniques being used for undetected smuggling are growing, causing a lapse in the effectiveness of detection techniques currently being used. The failure in the success of tackling heroin production and trade towards Europe is being increasingly recognised, which has resulted in a shift in focus onto the organised crime groups involved in the heroin trade within mainland Europe and the United Kingdom. An estimated 5,300 organised crime groups are believed to be active within the United Kingdom with an annual cost of in the region of between £20-40 billion. The complexity and level of intelligence within organised crime has evolved rapidly, and this, along with the increasing levels of corruption within heroin trading countries, give reason for the continual loss of the war against heroin. Concluding that until corruption and the highest hierarchical levels within organised crime groups are overthrown, positive results against the heroin trade will remain unseen, demonstrating that these key areas require further attention by governmental agencies and policies if the war is to be won.

From pots to plots: hierarchical trait‐based prediction of plant performance in a mesic grassland

Summary Traits are powerful predictors of ecosystem functions pointing to underlying physiological and ecological processes. Plant individual performance results from the coordinated operation of many processes, ranging from nutrient uptake over organ turnover to photosynthesis, thus requiring a large set of traits for its prediction. For plant performance on higher hierarchical levels, e.g. populations, additional traits important for plant‐plant and trophic interactions may be required which should even enlarge the spectrum of relevant predictor traits. The goal of this study was to assess the importance of plant functional traits to predict individual and population performance of grassland species with particular focus on the significance of root traits. We tested this for 59 grassland species using 35 traits divided into three trait clusters: leaf traits (16), stature traits (8) and root traits (11), using individual biomass of mesocosm plants as a measure of individual performance and population biomass of monocultures as a measure of population performance. We applied structural equation models to disentangle direct effects of single traits on population biomass and indirect effects via individual plant biomass or shoot density.We tested multivariate trait effects on individual and population biomass to analyse whether the importance of different trait clusters shifts with increasing hierarchical integration from individuals to populations. Traits of all three clusters significantly correlated with individual and population biomass. However, in spite of a number of significant correlations, above‐below‐ground linkages were generally weak, with few exceptions like N content. Stature traits exclusively affected population biomass indirectly via their effect on individual biomass, whereas root and leaf traits showed also direct effects and partly indirect effects via density. The inclusion of root traits in multiple regression models improved the prediction of individual biomass when compared with models with only above‐ground information only slightly (95% vs. 93% of variance prediction with and without root traits, respectively) but was crucial for the prediction of population biomass (77% and 49%, respectively). Root traits were more important for plant performance than leaf traits and were even the most important predictors at the population level Synthesis. Upscaling from the individual to the population level reflects an increasing number of processes requiring traits from different trait clusters for their prediction. Our results emphasize the importance of root traits for trait‐based studies especially at higher organizational levels. Our approach provides a comprehensive framework acknowledging the hierarchical nature of trait influences. This is one step towards a more process‐oriented assessment of trait‐based approaches.

The role of interoceptive inference in theory of mind

Inferring the intentions and beliefs of another is an ability that is fundamental for social and affiliative interactions. A substantial amount of empirical evidence suggests that making sense of another’s intentional and belief states (i.e. theory of mind) relies on exteroceptive (e.g. visual and auditory) and proprioceptive (i.e. motor) signals. Yet, despite its pivotal role in the guidance of behaviour, the role of the observer’s interoceptive (visceral) processing in understanding another’s internal states remains unexplored. Predicting and keeping track of interoceptive bodily states – which inform intentions and beliefs that guide behaviour – is one of the fundamental purposes of the human brain. In this paper, we will focus on the role of interoceptive predictions, prescribed by the free energy principle, in making sense of internal states that cause another’s behaviour. We will discuss how multimodal expectations induced at deep (high) hierarchical levels – that necessarily entail interoceptive predictions – contribute to inference about others that is at the heart of theory of mind.

The Repository of Soft Information within Bank Organizations

We examine who is the repository of soft information within bank organizations. Inconsistent with the conventional view of loan officers as the sole repository, we find that branch managers have the most soft information. We also find the repository at a higher hierarchical level at smaller banks. Furthermore, our evidence suggests that branch managers themselves actively collect soft information, especially at smaller banks. These findings suggest the need for a more nuanced view beyond the conventional emphasis on loan officers, and call for studies on the equilibrium design of the collection, processing, and use of soft information within bank organizations.

Optimal behaviour prediction using a primitive-based data-driven model-free iterative learning control approach

This paper suggests an optimal behaviour prediction mechanism for Multi Input-Multi Output control systems in a hierarchical control system structure, using previously learned solutions to simple tasks called primitives. The optimality of the behaviour is formulated as a reference trajectory tracking problem. The primitives are stored in a library of pairs of reference input/controlled output signals. The reference input primitives are optimized at the higher hierarchical level in a model-free iterative learning control (MFILC) framework without using knowledge of the controlled process. Learning of the reference input primitives is performed in a reduced subspace using radial basis functions for approximations. The convergence of the MFILC learning scheme is achieved via a Virtual Reference Feedback Tuning design of the feedback controllers in the lower level feedback control loops. The new complex trajectories to be tracked are decomposed into the output primitives regarded as basis functions. Next, the optimal reference input fed to the control system in order to track the desired new trajectory is then recomposed from the reference input primitives. The efficiency of this approach is demonstrated on a case study concerning the control of a two-axis positioning mechanism, and the experimental validation is offered.