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### Zuckerli: A New Compressed Representation for Graphs [article]

Luca Versari, Iulia M. Comsa, Alessio Conte, Roberto Grossi
2020 arXiv   pre-print
value of m as m · 2 j followed by l.  ...  We thus obtain each M i (x) by the following formula: M i (x) = y∈children(x) max-w (M R (y), {(x, y)} ∪ M i−1 (y)) where children(x) are the children of x in F , and max-w(A, B) returns the set of arcs  ...

### Intelligent Matrix Exponentiation [article]

Thomas Fischbacher and Iulia M. Comsa and Krzysztof Potempa and Moritz Firsching and Luca Versari and Jyrki Alakuijala
2020 arXiv   pre-print
The 2-norm of the difference between the outputs can be bound as follows: ∆ o 2 ≤ S 2 exp(M + M ) − exp(M ) F ≤ ≤ √ n S 2 exp(M + M ) − exp(M ) 2 ≤ ≤ √ n S 2 M 2 exp( M 2 ) exp( M 2 ) ≤ ≤ √ n S 2 δ in  ...  An output p m is obtained as follows, using the trainable parametersS mjk andṼ m : p m =Ṽ m +S mjk exp(M ) jk (3) The matrix exp(M ), indexed by row and column indices j and k in the same way as M , is  ...  This is precisely the monomial m we started with. By the definition of the exponential of the matrix, exp(U ) then contains m (d−1)! , which is the monomial up a constant factor.  ...

### Zuckerli: A New Compressed Representation for Graphs

Luca Versari, Iulia M. Comsa, Alessio Conte, Roberto Grossi
2020 IEEE Access
value of m as m · 2 j followed by l.  ...  We thus obtain each M i (x) by the following formula: M i (x) = y∈children(x) max-w (M R (y), {(x, y)} ∪ M i−1 (y)) where children(x) are the children of x in F , and max-w(A, B) returns the set of arcs  ...

### Transient topographical dynamics of the electroencephalogram predict brain connectivity and behavioural responsiveness during drowsiness [article]

Iulia M Comsa, Tristan A Bekinschtein, Srivas Chennu
2017 bioRxiv   pre-print
As we fall sleep, our brain traverses a series of gradual changes at physiological, behavioural and cognitive levels, which are not yet fully understood. The loss of responsiveness is a critical event in the transition from wakefulness to sleep. Here we seek to understand the electrophysiological signatures that reflect the loss of capacity to respond to external stimuli during drowsiness using two complementary methods: spectral connectivity and EEG microstates. Furthermore, we integrate these
more » ... two methods for the first time by investigating the connectivity patterns captured during individual microstate lifetimes. While participants performed an auditory semantic classification task, we allowed them to become drowsy and unresponsive. As they stopped responding to the stimuli, we report the breakdown of frontoparietal alpha networks and the emergence of frontoparietal theta connectivity. Further, we show that the temporal dynamics of all canonical EEG microstates slow down during unresponsiveness. We identify a specific microstate (D) whose occurrence and duration are prominently increased during this period. Employing machine learning, we show that the temporal properties of microstate D, particularly its prolonged duration, predicts the response likelihood to individual stimuli. Finally, we find a novel relationship between microstates and brain networks as we show that microstate D uniquely indexes significantly stronger theta connectivity during unresponsiveness. Our findings demonstrate that the transition to unconsciousness is not linear, but rather consists of an interplay between transient brain networks reflecting different degrees of sleep depth.

### Transient Topographical Dynamics of the Electroencephalogram Predict Brain Connectivity and Behavioural Responsiveness During Drowsiness

Iulia M. Comsa, Tristan A. Bekinschtein, Srivas Chennu
2018 Brain Topography
As we fall sleep, our brain traverses a series of gradual changes at physiological, behavioural and cognitive levels, which are not yet fully understood. The loss of responsiveness is a critical event in the transition from wakefulness to sleep. Here we seek to understand the electrophysiological signatures that reflect the loss of capacity to respond to external stimuli during drowsiness using two complementary methods: spectral connectivity and EEG microstates. Furthermore, we integrate these
more » ... two methods for the first time by investigating the connectivity patterns captured during individual microstate lifetimes. While participants performed an auditory semantic classification task, we allowed them to become drowsy and unresponsive. As they stopped responding to the stimuli, we report the breakdown of alpha networks and the emergence of theta connectivity. Further, we show that the temporal dynamics of all canonical EEG microstates slow down during unresponsiveness. We identify a specific microstate (D) whose occurrence and duration are prominently increased during this period. Employing machine learning, we show that the temporal properties of microstate D, particularly its prolonged duration, predicts the response likelihood to individual stimuli. Finally, we find a novel relationship between microstates and brain networks as we show that microstate D uniquely indexes significantly stronger theta connectivity during unresponsiveness. Our findings demonstrate that the transition to unconsciousness is not linear, but rather consists of an interplay between transient brain networks reflecting different degrees of sleep depth.

### Temporal Coding in Spiking Neural Networks with Alpha Synaptic Function: Learning with Backpropagation [article]

Iulia M. Comsa, Krzysztof Potempa, Luca Versari, Thomas Fischbacher, Andrea Gesmundo, Jyrki Alakuijala
2020 arXiv   pre-print
Given a classification problem with m inputs and n possible classes, the inputs are encoded as the spike times of individual neurons in the input layer and the result is encoded as the index of the neuron  ...

### SO(8) supergravity and the magic of machine learning

Iulia M. Comsa, Moritz Firsching, Thomas Fischbacher
2019 Journal of High Energy Physics
supergravity as an example, we show how modern Machine Learning software libraries such as Google's TensorFlow can be employed to greatly simplify the analysis of high-dimensional scalar sectors of some M-Theory  ...  K M AB := i 4 − ΨN Γ M AB N P Ψ P + 2 ΨM Γ B Ψ A − ΨM Γ A Ψ B + ΨB Γ M Ψ A Ω M N A := ∂ N e M A − ∂ M e N A ωMAB := ω M AB + i 4 ΨN Γ M AB N P Ψ P F M N P Q := 4δ RST U M N P Q ∂ R A ST U FMNP Q := F  ...  X F M N P Q F RST U A V W X + 3 4 • 12 2 ΨM Γ M N W XY Z Ψ N + 12 ΨW Γ XY Ψ Z F W XY Z + FW XY Z where e := det e M A D M (ω) := ∂ m − 1 4 ω M AB Γ AB , ω M AB := 1 2 (Ω ABM − Ω M AB − Ω BM A ) + K M AB  ...

### Ecological Microclimate Influence on Grapevine Phomopsis viticola Attack Frequency in Aiud-Ciumbrud Vineyards

Sergiu SAVU, Liliana Lucia TOMOIAGA, Veronica Sanda CHEDEA
2020 Bulletin of University of Agricultural Sciences and Veterinary Medicine Cluj-Napoca: Horticulture
The infections are favored by cold and wet weather (Comsa et al., 2012) .  ...  The first symptoms appear in early spring with the growing season, when bud break is delayed (Comsa et al., 2012) (Fig. 4A ).  ...

### Din însemnările profesorului Gheorghe Cantacuzino (1900–1977). III. Simpozionul neolitic organizat de Institutul de Arheologie din Bucureşti, în zilele de 30 noiembrie–2 decembrie 1972

George Trohani
2013 Cercetări Arheologice
m Nivel II Criş 2,40-2, 70 m Nivel I Criş, sol negru mătăsos.  ...  Profesorul Gheorghe Cantacuzino notează: Stratigrafia : strat de păşune, sol de pădure, material arheologic 0-0,25 m 0,25-1,80 m straturi geologice sterile arheologic 1,80-2 m Nivel JJJ Criş 2-2,40  ...

### Din însemnările Profesorului Gheorghe Cantacuzino (1900-1977). VI. Simpozionul de istorie şi arheologie româno-sovietic din 26-29 decembrie 1958

2018 Cercetări Arheologice
M. Comşa susţine că cultura Dridu se întâlneşte şi în numeroase localităţi din Bulgaria, unde nu poate fi vorba de originea străromână. Trebuie pentru cultura Dridu multă prudenţă. După M.  ...  Între aceste două straturi se interpune un strat cenuşos de 0,40 m şi un strat mai negricios de 0,10 m.  construcţie arată două podele cu două cuptoare.  ...

### Temporal Coding in Spiking Neural Networks With Alpha Synaptic Function: Learning With Backpropagation

Iulia-Maria Comsa, Krzysztof Potempa, Luca Versari, Thomas Fischbacher, Andrea Gesmundo, Jyrki Alakuijala
2021 IEEE Transactions on Neural Networks and Learning Systems
(Corresponding author: Iulia-Maria Comşa.)  ...  Iulia-Maria Comşa, Luca Versari, Thomas Fischbacher, Andrea Gesmundo, and Jyrki Alakuijala are with Google Research Zürich, 8002 Zürich, Switzerland (e-mail: iuliacomsa@google.com; veluca@google.com; tfish  ...

### TRANSYLVANIA AND THE OF INDO-EUROPEAN MIGRATION PROBLEM. THE ROMANIAN PARADIGM

Florin Gogâltan
2021 Lietuvos archeologija
Comşa also undertook serious work on the topic of the westward migration of the steppe peoples (Comșa 1976; 1978; 1980; 1998; etc.) .  ...  Furthermore, 'Dans ses territoires, les débuts du processus d'«indo-européanisation» se situent à la fin du IVe millénaire' (Comșa 1998, 29) . During the same conference, M.  ...

### SITUL ARHEOLOGIC DE LA ALBA IULIA-LUMEA NOUĂ. ISTORICUL CERCETĂRILOR

Mihai Gligor
2007 Series Historica, 11/I   unpublished
Aşezarea de la Alba Iulia-Lumea Nouă a fost descoperită întâmplător în anul 1942, în urma executării unor lucrări cu caracter edilitar.  ...  Rezultatul semnificativ al acestor prime cercetări de teren constă în evidenierea în stratul de cultură, cu grosime variabilă între 0,70-2,00 m-împărit în trei niveluri-a două categorii distincte de ceramică  ...  Comşa, Cultura Boian, p. 631. 46 S.  ...

### CERCETĂRI DE SUPRAFATĂ ÎN CADRUL SITULUI NEO-ENEOLITIC DE LA CÂLNlC-"iN

Vu
unpublished
In zona M-ţilor Sebeşului se găsesc cuarţite de diferite tipuri.  ...  Comuna Cl;lnic aparţine, prin amplasarea ci, iOnei sudice a judeţului Alba, fiind situată la aproximativ 35 km. est sud-est de municipiul Alba Iulia şi la la 5 km spre sud de comuna Cut, accesul efectuându-se  ...  >clreş:i (COMŞA 1971, 15-( 9) . , In cazul de faţă utilizarea, pc lângă piesele din silex descoperite, a ce!  ...

### Acta Terrae Septemcastrensis, IX

Sabin Luca, Sabin Luca, Lucian Blaga, Janusz Kozłowski, Zeno-Karl Pinter, Lucian Blaga, Marin Cârciumaru, Lucian Blaga, Marius-Mihai Ciută
2010 Acta Terrae Septemcastrensis   unpublished
Ciută, Începuturile neoliticului timpuriu în spaţiul intracarpatic transilvănean, Alba Iulia, 2005. Ciută 2005a M-M.  ...  Ciută 2009a M-M.  ...
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