Co-evolution and networks adaptation.

What is the role of co-evolution in the adaptation of a population of firms to a hostile environment ? To answer this question, we revisit network sociology starting from Kauffman s biological computer model. We apply a qualitative methodology to update exploitation and exploration mechanisms in nine Japanese interfirm networks. From these results, this article draws a typology of the adaptation forms, distinguishing pack, migratory, herd and colony networks.Sociologie des organisations; Réseaux d’entreprises;

Fear and Anxiety in Social Setting An Experimental Study

The purpose of this study was to examine the effects of dispositional and situational factors on cognitive biases. The theoretical background was based on Kimbrel’s Mediated Model of Social Anxiety and the revised reinforcement sensitivity theory by Gray and McNaughton. Two experiments were conducted. Study 1 (78 participants [85.9% females, aged 19–21 years]) included the induction of potential social threat, while in Study 2 (121 participants [85.1% females, aged 19–23 years]) real threat was used. The Reinforcement Sensitivity Questionnaire was employed as a measure of personality traits (Behavioral Inhibition System [BIS], Behavioral Approach System [BAS], Fight, Flight, and Freeze). Cognitive biases were assessed with the Dot Probe Task (attentional bias), Incidental Free Recall Task (memory bias), and Social Probability Cost Questionnaire (judgmental bias). The probability of occurrence of negative events was higher in the experimental group. BIS contributed positively to the prediction of probability of occurrence of negative events; and Freeze was positively related to attention bias toward pleasant stimuli. The results of the second study showed that experimentally induced circumstances of social threats did not affect cognitive biases. BIS and Freeze contributed positively to prediction of probability and distress in social context, while BIS was positively related with probability of occurrence of negative social events

The effect of subchronic supplementation with folic acid on homocysteine induced seizures

Influence of folic acid on the CNS is still unclear. Folate has a neuroprotective effect, while on the other hand excess folate can exacerbate seizures in epileptics. The aim of the present study was to examine the effect of subchronic administration of folic acid on behavioural and electroencephalographic (EEG) characteristics of DL homocysteine thiolactone induced seizures in adult rats. The activity of Na+/K+-ATPase and Mg2+-ATPase in different brain regions was investigated. Adult male Wistar rats were divided into groups: 1. Controls (C, 0.9% NaCl); 2. DL homocysteine-thiolactone 8.0 mmol/kg (H); 3. Subchronic supplementation with folic acid 5 mg/kg for 7 days (F) and 4. Subchronic supplementation with F + single dose of H (FH). Seizure behaviour was assessed by incidence, latency, number and intensity of seizure episodes. Seizure severity was described by a descriptive scale with grades 0–4. For EEG recordings, three gold-plated recording electrodes were implanted into the skull. Subchronic supplementation with folic acid did not affect seizure incidence, median number of seizure episodes and severity in FH, comparison with H (p > 0.05). The majority of seizure episodes in all groups were of grade 2. There were no significant differences in lethal outcomes at 24 h upon H injection in the FH vs. H group. The activity of Na+/K+-ATPase and Mg2+-ATPase was significantly increased in almost all examined structures in the FH vs. H group. Subchronic folic acid administration did not exacerbate H induced seizures and completely recovered the activity of ATPases

A novel technology in freight transportation for improvement of the environmental impact

New technological innovations of eco-friendly vehicles combined with the usage of renewable energy sources showed significant results in mitigating emissions. In this thesis, we consider the eHighway system, a recent technology based on electrified roads. It is designed to supply new hybrid trucks, i.e. electric overhead catenary (OC) trucks, which are connected to overhead power lines through a pantograph positioned at the top of the vehicle. The eHighway implementation can result in lower emission vehicles’ rate since the vehicles are operating with electric mode. Therefore, in this thesis, we present a single-level multi-objective network design model and a bi-level multi-objective network design model considering a novel technology, the eHighway system. The proposed models investigate the opportunities of adopting eHighways and evaluating its environmental benefits considering limited budget resources for infrastructure electrification. Additionally, the models could be considered as useful tools for decision-makers in eHighway network planning and design. For developing both models, a simulation model presented in the literature was used to calculate the number of traction substations needed for arc electrification according to hybrid trucks flows. As a first approach, in the case of the single-level multi-objective network design model, we propose a formulation including three objectives: minimisation of infrastructure and environmental costs, maximisation of average traffic density of OC hybrid trucks on electrified arcs. The Pareto optimisation approach is considered for a comprehensive analysis of all possible solutions according to different criteria weights. This model served as a basis to construct a bi-level multi-objective network design model that also considers the possibility of increasing the capacity of electrified arcs to improve overall network performances. Thus, in the case of the bi-level network design model we considered four objectives in the upper level related to the minimisation of the total Overhead Catenary (OC) hybrid trucks’ travel time, infrastructure and environmental costs and maximisation of average traffic density of OC hybrid trucks on electrified arcs. The decision of the upper level depends on the output of the lower level which is formulated as a Stochastic Users Equilibrium traffic assignment based on a fixed-point problem. Moreover, the proposed bi-level network design model deals not only with finding the set of the arcs to be electrified but also with the capacity expansion of the electrified arcs for improving the performance of the overall system. Additionally, genetic algorithms were used as a solution approach, which demonstrated the effectiveness in finding the near-optimal results in a reasonable computation time. The proposed models have been tested on a medium-sized network and the Sioux-Falls network. In particular, we analysed the Pareto front obtained from the single-level model, where non-dominant solutions are identified according to the three considered criteria. Moreover, a sensitivity analysis is carried out for the bi-level problem in terms of criteria weights and the percentage of hybrid vehicles using the eHighway system. Numerical results quantified the environmental improvement we can obtain by using the eHighway system in both models, which can be a basis for making decisions regarding the adoption of this new technology

Doctor of Philosophy

dissertationThe present study investigated the effects of the explicit teaching of formulaic sequences (i.e., academic and topic-induced) on L2 writing. The research examined separately the effects of the treatment on the students' abilities to produce the target formulaic sequences in controlled (i.e., C-tests) and uncontrolled situations (i.e., essays), and to produce better quality essays. The study, through posttreatment interviews, also attempted to glean insights into the approaches L2 writers use for the production of the target formulaic sequences. The study found that the students in the treatment condition performed at a significantly higher level than the students in the control condition on measures of the production of academic formulaic sequences in a controlled situation and the production of topic-induced formulaic sequences in controlled and uncontrolled situations, but there were no significant differences between the groups on the measures of students' abilities to produce academic formulaic sequences in an uncontrolled situation and to produce better quality writing. The results of the study suggest that the explicit instruction facilitated learning of the target formulaic sequences when the learning is measured by a test. Most importantly, the study found that explicit instruction helped students become familiar enough with the formulaic sequences to recognize their usefulness and employ them in their essays. The results indicated that the instructional approach helped low performing writers produce iv essays of better quality and high performing writers increase the awareness of the frequencies and functions of the formulaic sequencers in expert writers' texts. The findings from the interviews indicated that the students' abilities to produce the academic and topic-induced formulaic sequences in their compositions may depend on the students' perceived need to use them in their writing, and that students' abilities to produce the academic formulaic sequences in essays may be influenced by the interaction of students' awareness of the frequency and functions of academic formulaic sequences and their motivation to sound academic in their writing. The study results suggest that the instructional approach may be helpful for the students' learning of formulaic sequences for the purposes of writing and should be the focus of future experimental research

Group culture, workplace diversity and organizational innovativeness: Evidence from Serbia

We examine the relationship between group culture – which emphasizes mentoring, teamwork and loyalty – and innovativeness in organizations. The relationship between group culture and innovativeness is assumed to be positive; group culture fosters trust and knowledge sharing which is conducive to joint creativity and collaboration necessary for the innovation process. Drawing on social categorization theory and key insights from gender studies, we develop a more nuanced argument that this positive relationship is bounded by gender diversity within the organization; organizations that are highly gender diverse will suffer from a ‘rejection of others’ barrier when high levels of group culture are imposed on employees. Analysis of survey data from 407 individuals working for organizations of different types and sizes in Serbia gives support to our main argument. We discuss implications of this for theory and management practice as well as policy implications for transition economies

Predlog metoda za određivanje stabilnosti u vodi ekstrudirane hrane za ribe

Važan parametar fizičkog kvaliteta ekstrudirane hrane za ribe jeste njena stabilnost u vodi, koja se definiše kao svojstvo peleta uronjenih u vodu da zadrže svoj fizički oblik uz minimalno raspadanje i gubitak nutritivnih komponeneti sve do momenta njenog unosa od strane riba. Stabilnost u vodi hrane je važna za sve akvatične vrste, kako za pastrmke i losose koji se hrane sporotonućom hranom, tako i naročito za one koje se sporo hrane, kao što su škampi, gde je potrebno da hrana satima u vodi zadrži oblik i sve potrebne hranljive materije. Mala stabilnost hrane u vodi dovodi do slabog rasta riba, neefikasne konverzije i ekonomskih gubitaka, te stoga hrana za ribe mora posedovati visoku stabilnost u vodi kako bi se ribama obezbedila najveća moguća količina hranljivih materija a tako dovelo i do smanjenje troškova proizvodnje. U ovom radu određena je stabilnost u vodi tri različite grupe hrane za losose korišćenjem tri metode: statičke metoda, metode mokrog prosejavanja natopljenih peleta i konduktometrijske metode, kao novog pristupa određivanja stabilnosti ekstrudirane hrane za ribe u vodi. Za ispitivanje stabilnosti odabrana su tri uzorka ekstrudirane hrane za losose tako da poseduju različitu stabilnost u vodi. Cilj istraživanja bio je da se testirajem metoda ispita njihov potencijal za određivanje stabilnosti hrane za ribe, kao i da se proveri međusobna korelacija predloženih metoda. Na osnovu rezultata ispitivanja, za sve tri korišćene metode primećene su statistički značajne ralike (p<0,05) između uzoraka ekstrudirane hrane za losose. Rezultati dobijeni korišćenjem predloženih metoda pokazali su da je najmanju stabilnost u vodi imao uzorak hrane A, dok je najveću imao uzorak hrane C. Iako se statički metod pokazao kao pogodan za odreživanje maksimalne vrednosti stabilnosti hrane za ribe u vodi, metod mokrog prosejavanja pokazao se kao bolji izbor jer daje jasnije razlike između pojedinačnih uzoraka. Konduktometrijska metoda na osnovu izračunatog koeficijenta varijacije (cv=0,02%) imala je najveću tačnost od sve tri predložene metode. Primećena je pozitivna korelacija između statičke i metode mokrog prosejavanja (r=0,999; p=0,02), nešto niža korelacija između konduktometrijske i statičke metode (r=0,999; p=0,03), dok je najniža korelacija prisutna između konduktometrijske i metode mokrog prosejavanja (r=0,997; p=0,05), na granici poverenja od 95%. Prednost konduktometrijske metode u odnosu na ostale ispitivane metode ogleda se u mogućnosti direktnog merenja, brzini i osetljivosti

Integration-responsiveness, local hires and subsidiary performance amidst turbulence: Insights from a survey of Chinese subsidiaries

We study MNE subsidiary performance in a turbulent, emerging economy, focusing on how locally hired managers and integration − responsiveness (I-R) influence performance outcomes. We augment I-R by considering how locally hired managers support or hinder global integration (GI) and local responsiveness (LR) in China. Analysis of data from 104 Chinese subsidiaries suggests higher proportions of locally hired managers do not support GI; GI is sufficient in its own right in dealing with turbulence, positively moderating the relationship between turbulence and performance. However, a higher proportion of locally hired managers does improve subsidiary performance amidst turbulence when accompanied by LR

Towards the electrification of freight transport: A network design model for assessing the adoption of eHighways

The development of new technological innovations for eco-friendly vehicles combined with the usage of renewable energy sources is essential for mitigating the environmental impact of freight transport. In this context, this paper investigates the opportunities for implementing the eHighway system, a novel recent technology designed to supply new hybrid trucks. This technology uses overhead catenary heavy-duty vehicles that are supplied with electric energy from overhead power lines through a pantograph that is positioned at the top of the truck. A novel bi-level multi-objective network electrification design (BM-NED) model is proposed to assess the environmental benefits and opportunities of adopting eHighways, considering the limited budgetary resources for road infrastructure electrification. Still, the implementation of eHighways requires collaboration between public and private stakeholder interests. The upper level considers multiple objectives aiming at minimizing the total travel cost, infrastructure, and environmental costs and maximizing the average traffic density of OC hybrid trucks on electrified arcs, whereas the lower level is the traffic assignment model. The Elitist multi-objective Genetic Algorithms are used as a solution approach for the multi-objective optimization and the Pareto front of the non-dominated solutions have been generated. Results of the model, tested on a part of a motorway network in the Veneto region in Italy, show that the implementation of the eHighway system can lead to an average emission reduction of about 66%, considering all Pareto-optimal solutions. Furthermore, a sensitivity analysis has been carried out by giving different weights to the objective functions that can be a basis for decision-makers regarding the adoption of this new technology