Fabrizio Parente - Academia.edu (original) (raw)
Papers by Fabrizio Parente
Journal of Economic Studies
PurposeThis paper explores international trade of the Chinese manufacturing industries through th... more PurposeThis paper explores international trade of the Chinese manufacturing industries through the lenses of network analysis (NA) to visualise the world trade network of the Chinese economy, describe its topology and better explain the international organisation of Chinese manufacturing industries.Design/methodology/approachThe authors built a dataset of 40,550 Chinese companies and their 107,026 subsidiaries in 118 countries from Orbis-BVD and used a NA to investigate the connection between China and other countries. In particular, the authors studied the connections between Chinese companies and their subsidiaries in order to build a network of Chinese industries.FindingsThe authors found that the network of Chinese companies is ramified but not wide and it can be divided into two clusters. Moreover, the relations between China and other peripheral countries are strongly mediated by a few leading locations (e.g. Hong Kong and the USA).Originality/valueThis paper contributes to th...
Up to now positive, coactivating interactions polarized the attention of people studying the time... more Up to now positive, coactivating interactions polarized the attention of people studying the time-dependent functional connectivity of brain networks: we report here about the negative, deactivating interactions observed, in the same above contest, after filtering by appropriate thresholds the intensities of BOLD signals from coupled brain regions. The final aims of our strategy remain: 1) studying the de-activating interactions in their essential role of keeping stationary any functional brain state, and 2) exploiting the opportunity of clustering different subjects from functional parameters recorded under the favorable condition offered by the Resting State.
European Psychiatry, 2015
Introduction Data show impairment in Social Cognition (SC) in schizophrenia underlining also the ... more Introduction Data show impairment in Social Cognition (SC) in schizophrenia underlining also the diagnostic importance of neuroimaging in this area. So, it seems important to identify possible correlations between SC and structural brain abnormalities. Objectives 1)Evaluate differences in emotional recognition between schizophrenics and healthy controls and the structural characteristics of the anterior left and right thalamic radiation (TR) of both groups. 2)Identify possible association between sociocognitive abilities and structural characteristics of the thalamic radiation. Aims Investigate the relationship between anomalies in integrity and fiber orientation of anterior TR and sociocognitive performance in schizophrenia. Methods 27 Schizophrenics (SCID-I), age-matched with 11 healthy controls, were evaluated with The awareness of Social Inference Test (TASIT) to assess emotion and conversation literally and non-literally remarks recognition. DTI images –with measure of fractional anisotropy (FA) of TR– were collected using 3T-MRI scanner. Mixed-design ANOVA was performed on right and left FA. MANOVA was performed on TASIT. Results Deficits in recognition of positive and negative emotions, perceive sarcasm, distinguish between truth and lies were observed. Moreover, significant negative correlations between FA of left TR and scores in “Positive Emotions” (r=-466,p=.019), “Total Emotions” (r=-411,p=.041), “Lie” (r=-451,p=.024) and a negative significant correlation between FA right TR and scores “sincerity” (r=-522,p=.009), were observed. Conclusions These preliminary results confirm that SC is impaired in schizophrenia and show that increased FA of left and right TR correlates with lower TASIT scores. These results highlight the role of TR in emotion regulation suggesting that structural anomalies could result in worse sociocognitive performance.
Rivista di psichiatria
Tardive dyskinesia is a potentially fatal side effect of antipsychotics. In the classic form is c... more Tardive dyskinesia is a potentially fatal side effect of antipsychotics. In the classic form is characterized by involuntary hyperkinetic movements, especially those affecting the mimic and mastication muscles. The main hypothesis considers that the pathophysiological basis of the disorder is an overexpression of D2 receptors in the striatum, in response to dopamine block neuroleptics-mediated, especially the older ones. Because fortunately not all patients undergo this severe adverse effects, many efforts have been conducted in trying to delineate the risk factors so as to try to prevent tardive dyskinesia by administering lower doses of neuroleptics in vulnerable groups. Advanced age, female sex, smoking habits, diabetes mellitus, alcohol abuse are known as risk factors. The instead the role of the type of psychiatric disorder, instead, is still debated. Since there was a direct relationship between cumulative dose of antipsychotic and treatment duration, recent studies are aimed ...
Forum Scientiae Oeconomia, 2022
Contemporary economic networks operate in a turbulent geo-economic context in which the external ... more Contemporary economic networks operate in a turbulent geo-economic context in which the external environment determines the formation or disintegration of such networks. The article focuses on economic networks through the prism of network analysis, actor-network theory, and network theory. As a consequence, the authors attempted to develop an actor-network model, taking into account the geo-economic context, social and technical actors, their roles and positions in the economic network, and network measures (centrality, knowledge/resource/task diversity, and redundancy). Due to the conceptual nature of the article, a less formalised, narrative literature review was used, which allowed for the free selection of literature and its interpretation in the context of the research question posed. As a result, a conceptual actor-network model for economic networks was created, understood as a framework for the analysis of the network of relations, interactions, and interdependencies occurring between the socio-technical actors of the economic networks through the prism of the allocation and distribution of information, knowledge, resources, and tasks. The actor-network model is the starting point for further, more advanced research, as well as the operationalisation and validation of the model, which would contribute to the actor-network theory and network theory. In this conceptual form, the presented actor-network model seems to be universal, and its application is possible whenever we can identify actors and the relationships between them. Its implementation in the study of economic networks in any sector is conditioned by the definition of social and technical actors; their relations, roles, and positions in the network affecting the efficiency of the network as a whole.
This paper provides a contribution to understand anti- (or negative) correlations between brain r... more This paper provides a contribution to understand anti- (or negative) correlations between brain regions in fMRI studies. We report about: 1) characterizing negative correlations under physiological conditions through a careful analysis of records from healthy people; 2) reproducing a (homeostatic) equilibrium between different brain areas by a Multi Agent System and a negative retroaction mechanism on a small network model.
Scientific Reports, 2021
This paper deals with the information transfer mechanisms underlying causal relations between bra... more This paper deals with the information transfer mechanisms underlying causal relations between brain regions under resting condition. fMRI images of a large set of healthy individuals from the 1000 Functional Connectomes Beijing Zang dataset have been considered and the causal information transfer among brain regions studied using Transfer Entropy concepts. Thus, we explored the influence of a set of states in two given regions at time t (At Bt.) over the state of one of them at a following time step (Bt+1) and could observe a series of time-dependent events corresponding to four kinds of interactions, or causal rules, pointing to (de)activation and turn off mechanisms and sharing some features with positive and negative functional connectivity. The functional architecture emerging from such rules was modelled by a directional multilayer network based upon four interaction matrices and a set of indexes describing the effects of the network structure in several dynamical processes. Th...
International Journal of Industrial and Manufacturing Systems Engineering, 2020
Neural Plasticity, 2018
Anticorrelations among brain areas observed in fMRI acquisitions under resting state are not endo... more Anticorrelations among brain areas observed in fMRI acquisitions under resting state are not endowed with a well-defined set of characters. Some evidence points to a possible physiological role for them, and simulation models showed that it is appropriate to explore such an issue. A large-scale brain representation was considered, implementing an agent-based brain-inspired model (ABBM) incorporating the SER (susceptible-excited-refractory) cyclic mechanism of state change. The experimental data used for validation included 30 selected functional images of healthy controls from the 1000 Functional Connectomes Classic collection. To study how different fractions of positive and negative connectivities could modulate the model efficiency, the correlation coefficient was systematically used to check the goodness-of-fit of empirical data by simulations under different combinations of parameters. The results show that a small fraction of positive connectivity is necessary to match at best...
Scientific Reports, 2020
The focus of this paper is on the functional role of brain regions focusing on their modular arch... more The focus of this paper is on the functional role of brain regions focusing on their modular architecture and individual variability. Our main assumption is that the more variable anti-correlation patterns reflect random connections, while the more conserved ones play a functional role. Within this framework, we expanded on previous results using a different database and a different methodological approach. Aiming to identify the role of specific functional connections within a global network organization which includes subnetworks, we found that the fronto-parietal module acts as the main source of anti-correlations. In addition, the pre-frontal regions (namely: frontal middle, frontal middle orbital, frontal inferior triangular) and the parietal inferior region are highly conserved and, at the same time, act as highly connected nodes, thus confirming their importance in functional modulation.
Brain Imaging and Behavior, 2017
The anticorrelations in fMRI measurements are still not well characterized, but some new evidence... more The anticorrelations in fMRI measurements are still not well characterized, but some new evidences point to a possible physiological role. We explored the topology of functional brain networks characterized by negative edgess and their possible alterations in schizophrenia, using functional images of 8 healthy subjects and 8 schizophrenic patients in a resting state condition. In order to minimize the insertion of artifactual negative correlations, the preprocessing of images was carried out by the CompCorr procedure, and the results compared with the Global Signal Regression (GSR) procedure. The degree distribution, the centrality, the efficiency and the rich-club behavior were used to characterize the functional brain network with negative links of healthy controls in comparison with schizophrenic patients. The results show that functional brain networks with both positive and negative values have a truncated power-law degree distribution. Moreover, although functional brain networks characterized by negative values have not small-world topology, they show a specific disassortative configuration: the more connected nodes tend to have fewer connections between them. This feature is lost using the GSR procedure. Finally, the comparison with schizophrenic patients showed a decreased (local and global) efficiency associated to a decreased connectivity among central nodes. As a conclusion, functional brain networks characterized by negative values, despite lacking a well defined topology, show specific features, different from random, and indicate an implication in the alterations associated to schizophrenia.
Rivista Di Psichiatria, May 1, 2013
Biophysics and Bioengineering Letters, Dec 12, 2014
Psychiatry research, Jan 28, 2015
Executive functioning is consistently impaired in schizophrenia, and it has been associated with ... more Executive functioning is consistently impaired in schizophrenia, and it has been associated with reduced gray matter volume in prefrontal areas. Abnormalities in prefrontal brain regions have also been related to the illness duration. The aim of the study was to investigate the effect of executive functioning decline and chronicity in prefrontal regions of patients with schizophrenia. Participants comprised 33 schizophrenic patients, 18 with duration of illness (DoI) shorter than 10 years and 15 with duration of illness longer than 10 years. In addition, 24 healthy controls served as a comparison group. Participants performed the Wisconsin Card Sorting Test (WCST) and underwent structural magnetic resonance imaging. Patients with longer DoI showed significant reduction of gray matter volume in the left medial frontal gyrus compared with healthy controls. Moreover, there was a trend for greater gray matter volume decrease in patients with a longer illness duration compared with patie...
Schizophrenia Research, 2012
Schizophrenia Research, 2014
Schizophrenia Research, 2014
Background: Schizophrenia is characterized by a dramatically increased mortality leading to an ea... more Background: Schizophrenia is characterized by a dramatically increased mortality leading to an earlier age of death of about ten years compared with the general population. Suicidality is the major determinant of this highly increased mortality. Thus, exploring the neuronal foundations of suicidality is essential for a better understanding, recognizing and prevention of suicidal behaviour in schizophrenia. Recent studies focused on grey matter volume differences between suicide-attempters and non-attempters in schizophrenia. However, an analysis of the cortex structure in terms of cortical thickness and folding in order to further elucidate the neuroanatomical correlates of suicidality in schizophrenia has yet not been performed. Thus, in the present study we sought to identify relevant brain regions with differences in cortical thickness and folding between patients with suicide-attempts, patients without any suicidal thoughts (neither active nor passive) and healthy controls with a fine grained surface-based MRI method. Methods: A group of 37 patients with schizophrenia according to DSM-IV, therefrom 14 suicide-attempters and 23 non-suicidal, and 50 ageand gender-matched healthy controls were included. Suicidality was documented through clinical interview and chart review. All participants underwent high-resolution T1-weighted MRI scans (1.5-T). Whole brain node-by-node cortical thickness and folding were estimated (FreeSurfer Software) and compared between the three groups. Results: Significant (p<0.05, corrected) cortical thinning in patients with suicide attempts compared with non-suicidal patients in the right superior and middle temporal, temporopolar and insular cortex was found. Additionally, patients with suicide attempts showed reduced cortical thickness in the right dorsolateral prefrontal cortex (p<0.001, uncorrected). No significant differences were found for cortical folding. Discussion: Our findings provide new evidence for potential neuroanatomical underpinnings of suicidality in schizophrenia. The affected regions of cortical thinning in suicide attempters are strongly involved in cortical networks relevant for the regulation of impulsivity, emotions and planning of behaviour. Thus, anatomical alterations in these regions are highly suggestive to be of impact for suicidal behaviour in schizophrenia. Further studies in larger samples are needed to consolidate these initial findings.
Journal of Economic Studies
PurposeThis paper explores international trade of the Chinese manufacturing industries through th... more PurposeThis paper explores international trade of the Chinese manufacturing industries through the lenses of network analysis (NA) to visualise the world trade network of the Chinese economy, describe its topology and better explain the international organisation of Chinese manufacturing industries.Design/methodology/approachThe authors built a dataset of 40,550 Chinese companies and their 107,026 subsidiaries in 118 countries from Orbis-BVD and used a NA to investigate the connection between China and other countries. In particular, the authors studied the connections between Chinese companies and their subsidiaries in order to build a network of Chinese industries.FindingsThe authors found that the network of Chinese companies is ramified but not wide and it can be divided into two clusters. Moreover, the relations between China and other peripheral countries are strongly mediated by a few leading locations (e.g. Hong Kong and the USA).Originality/valueThis paper contributes to th...
Up to now positive, coactivating interactions polarized the attention of people studying the time... more Up to now positive, coactivating interactions polarized the attention of people studying the time-dependent functional connectivity of brain networks: we report here about the negative, deactivating interactions observed, in the same above contest, after filtering by appropriate thresholds the intensities of BOLD signals from coupled brain regions. The final aims of our strategy remain: 1) studying the de-activating interactions in their essential role of keeping stationary any functional brain state, and 2) exploiting the opportunity of clustering different subjects from functional parameters recorded under the favorable condition offered by the Resting State.
European Psychiatry, 2015
Introduction Data show impairment in Social Cognition (SC) in schizophrenia underlining also the ... more Introduction Data show impairment in Social Cognition (SC) in schizophrenia underlining also the diagnostic importance of neuroimaging in this area. So, it seems important to identify possible correlations between SC and structural brain abnormalities. Objectives 1)Evaluate differences in emotional recognition between schizophrenics and healthy controls and the structural characteristics of the anterior left and right thalamic radiation (TR) of both groups. 2)Identify possible association between sociocognitive abilities and structural characteristics of the thalamic radiation. Aims Investigate the relationship between anomalies in integrity and fiber orientation of anterior TR and sociocognitive performance in schizophrenia. Methods 27 Schizophrenics (SCID-I), age-matched with 11 healthy controls, were evaluated with The awareness of Social Inference Test (TASIT) to assess emotion and conversation literally and non-literally remarks recognition. DTI images –with measure of fractional anisotropy (FA) of TR– were collected using 3T-MRI scanner. Mixed-design ANOVA was performed on right and left FA. MANOVA was performed on TASIT. Results Deficits in recognition of positive and negative emotions, perceive sarcasm, distinguish between truth and lies were observed. Moreover, significant negative correlations between FA of left TR and scores in “Positive Emotions” (r=-466,p=.019), “Total Emotions” (r=-411,p=.041), “Lie” (r=-451,p=.024) and a negative significant correlation between FA right TR and scores “sincerity” (r=-522,p=.009), were observed. Conclusions These preliminary results confirm that SC is impaired in schizophrenia and show that increased FA of left and right TR correlates with lower TASIT scores. These results highlight the role of TR in emotion regulation suggesting that structural anomalies could result in worse sociocognitive performance.
Rivista di psichiatria
Tardive dyskinesia is a potentially fatal side effect of antipsychotics. In the classic form is c... more Tardive dyskinesia is a potentially fatal side effect of antipsychotics. In the classic form is characterized by involuntary hyperkinetic movements, especially those affecting the mimic and mastication muscles. The main hypothesis considers that the pathophysiological basis of the disorder is an overexpression of D2 receptors in the striatum, in response to dopamine block neuroleptics-mediated, especially the older ones. Because fortunately not all patients undergo this severe adverse effects, many efforts have been conducted in trying to delineate the risk factors so as to try to prevent tardive dyskinesia by administering lower doses of neuroleptics in vulnerable groups. Advanced age, female sex, smoking habits, diabetes mellitus, alcohol abuse are known as risk factors. The instead the role of the type of psychiatric disorder, instead, is still debated. Since there was a direct relationship between cumulative dose of antipsychotic and treatment duration, recent studies are aimed ...
Forum Scientiae Oeconomia, 2022
Contemporary economic networks operate in a turbulent geo-economic context in which the external ... more Contemporary economic networks operate in a turbulent geo-economic context in which the external environment determines the formation or disintegration of such networks. The article focuses on economic networks through the prism of network analysis, actor-network theory, and network theory. As a consequence, the authors attempted to develop an actor-network model, taking into account the geo-economic context, social and technical actors, their roles and positions in the economic network, and network measures (centrality, knowledge/resource/task diversity, and redundancy). Due to the conceptual nature of the article, a less formalised, narrative literature review was used, which allowed for the free selection of literature and its interpretation in the context of the research question posed. As a result, a conceptual actor-network model for economic networks was created, understood as a framework for the analysis of the network of relations, interactions, and interdependencies occurring between the socio-technical actors of the economic networks through the prism of the allocation and distribution of information, knowledge, resources, and tasks. The actor-network model is the starting point for further, more advanced research, as well as the operationalisation and validation of the model, which would contribute to the actor-network theory and network theory. In this conceptual form, the presented actor-network model seems to be universal, and its application is possible whenever we can identify actors and the relationships between them. Its implementation in the study of economic networks in any sector is conditioned by the definition of social and technical actors; their relations, roles, and positions in the network affecting the efficiency of the network as a whole.
This paper provides a contribution to understand anti- (or negative) correlations between brain r... more This paper provides a contribution to understand anti- (or negative) correlations between brain regions in fMRI studies. We report about: 1) characterizing negative correlations under physiological conditions through a careful analysis of records from healthy people; 2) reproducing a (homeostatic) equilibrium between different brain areas by a Multi Agent System and a negative retroaction mechanism on a small network model.
Scientific Reports, 2021
This paper deals with the information transfer mechanisms underlying causal relations between bra... more This paper deals with the information transfer mechanisms underlying causal relations between brain regions under resting condition. fMRI images of a large set of healthy individuals from the 1000 Functional Connectomes Beijing Zang dataset have been considered and the causal information transfer among brain regions studied using Transfer Entropy concepts. Thus, we explored the influence of a set of states in two given regions at time t (At Bt.) over the state of one of them at a following time step (Bt+1) and could observe a series of time-dependent events corresponding to four kinds of interactions, or causal rules, pointing to (de)activation and turn off mechanisms and sharing some features with positive and negative functional connectivity. The functional architecture emerging from such rules was modelled by a directional multilayer network based upon four interaction matrices and a set of indexes describing the effects of the network structure in several dynamical processes. Th...
International Journal of Industrial and Manufacturing Systems Engineering, 2020
Neural Plasticity, 2018
Anticorrelations among brain areas observed in fMRI acquisitions under resting state are not endo... more Anticorrelations among brain areas observed in fMRI acquisitions under resting state are not endowed with a well-defined set of characters. Some evidence points to a possible physiological role for them, and simulation models showed that it is appropriate to explore such an issue. A large-scale brain representation was considered, implementing an agent-based brain-inspired model (ABBM) incorporating the SER (susceptible-excited-refractory) cyclic mechanism of state change. The experimental data used for validation included 30 selected functional images of healthy controls from the 1000 Functional Connectomes Classic collection. To study how different fractions of positive and negative connectivities could modulate the model efficiency, the correlation coefficient was systematically used to check the goodness-of-fit of empirical data by simulations under different combinations of parameters. The results show that a small fraction of positive connectivity is necessary to match at best...
Scientific Reports, 2020
The focus of this paper is on the functional role of brain regions focusing on their modular arch... more The focus of this paper is on the functional role of brain regions focusing on their modular architecture and individual variability. Our main assumption is that the more variable anti-correlation patterns reflect random connections, while the more conserved ones play a functional role. Within this framework, we expanded on previous results using a different database and a different methodological approach. Aiming to identify the role of specific functional connections within a global network organization which includes subnetworks, we found that the fronto-parietal module acts as the main source of anti-correlations. In addition, the pre-frontal regions (namely: frontal middle, frontal middle orbital, frontal inferior triangular) and the parietal inferior region are highly conserved and, at the same time, act as highly connected nodes, thus confirming their importance in functional modulation.
Brain Imaging and Behavior, 2017
The anticorrelations in fMRI measurements are still not well characterized, but some new evidence... more The anticorrelations in fMRI measurements are still not well characterized, but some new evidences point to a possible physiological role. We explored the topology of functional brain networks characterized by negative edgess and their possible alterations in schizophrenia, using functional images of 8 healthy subjects and 8 schizophrenic patients in a resting state condition. In order to minimize the insertion of artifactual negative correlations, the preprocessing of images was carried out by the CompCorr procedure, and the results compared with the Global Signal Regression (GSR) procedure. The degree distribution, the centrality, the efficiency and the rich-club behavior were used to characterize the functional brain network with negative links of healthy controls in comparison with schizophrenic patients. The results show that functional brain networks with both positive and negative values have a truncated power-law degree distribution. Moreover, although functional brain networks characterized by negative values have not small-world topology, they show a specific disassortative configuration: the more connected nodes tend to have fewer connections between them. This feature is lost using the GSR procedure. Finally, the comparison with schizophrenic patients showed a decreased (local and global) efficiency associated to a decreased connectivity among central nodes. As a conclusion, functional brain networks characterized by negative values, despite lacking a well defined topology, show specific features, different from random, and indicate an implication in the alterations associated to schizophrenia.
Rivista Di Psichiatria, May 1, 2013
Biophysics and Bioengineering Letters, Dec 12, 2014
Psychiatry research, Jan 28, 2015
Executive functioning is consistently impaired in schizophrenia, and it has been associated with ... more Executive functioning is consistently impaired in schizophrenia, and it has been associated with reduced gray matter volume in prefrontal areas. Abnormalities in prefrontal brain regions have also been related to the illness duration. The aim of the study was to investigate the effect of executive functioning decline and chronicity in prefrontal regions of patients with schizophrenia. Participants comprised 33 schizophrenic patients, 18 with duration of illness (DoI) shorter than 10 years and 15 with duration of illness longer than 10 years. In addition, 24 healthy controls served as a comparison group. Participants performed the Wisconsin Card Sorting Test (WCST) and underwent structural magnetic resonance imaging. Patients with longer DoI showed significant reduction of gray matter volume in the left medial frontal gyrus compared with healthy controls. Moreover, there was a trend for greater gray matter volume decrease in patients with a longer illness duration compared with patie...
Schizophrenia Research, 2012
Schizophrenia Research, 2014
Schizophrenia Research, 2014
Background: Schizophrenia is characterized by a dramatically increased mortality leading to an ea... more Background: Schizophrenia is characterized by a dramatically increased mortality leading to an earlier age of death of about ten years compared with the general population. Suicidality is the major determinant of this highly increased mortality. Thus, exploring the neuronal foundations of suicidality is essential for a better understanding, recognizing and prevention of suicidal behaviour in schizophrenia. Recent studies focused on grey matter volume differences between suicide-attempters and non-attempters in schizophrenia. However, an analysis of the cortex structure in terms of cortical thickness and folding in order to further elucidate the neuroanatomical correlates of suicidality in schizophrenia has yet not been performed. Thus, in the present study we sought to identify relevant brain regions with differences in cortical thickness and folding between patients with suicide-attempts, patients without any suicidal thoughts (neither active nor passive) and healthy controls with a fine grained surface-based MRI method. Methods: A group of 37 patients with schizophrenia according to DSM-IV, therefrom 14 suicide-attempters and 23 non-suicidal, and 50 ageand gender-matched healthy controls were included. Suicidality was documented through clinical interview and chart review. All participants underwent high-resolution T1-weighted MRI scans (1.5-T). Whole brain node-by-node cortical thickness and folding were estimated (FreeSurfer Software) and compared between the three groups. Results: Significant (p<0.05, corrected) cortical thinning in patients with suicide attempts compared with non-suicidal patients in the right superior and middle temporal, temporopolar and insular cortex was found. Additionally, patients with suicide attempts showed reduced cortical thickness in the right dorsolateral prefrontal cortex (p<0.001, uncorrected). No significant differences were found for cortical folding. Discussion: Our findings provide new evidence for potential neuroanatomical underpinnings of suicidality in schizophrenia. The affected regions of cortical thinning in suicide attempters are strongly involved in cortical networks relevant for the regulation of impulsivity, emotions and planning of behaviour. Thus, anatomical alterations in these regions are highly suggestive to be of impact for suicidal behaviour in schizophrenia. Further studies in larger samples are needed to consolidate these initial findings.