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Artigo Acesso aberto Revisado por pares

Marco Porta,

The PopescuGabriel theorem states that each Grothendieck abelian category is a localization of a module category. In this paper, ...

Tópico(s): Advanced Topics in Algebra

2010 - Elsevier BV | Advances in Mathematics

Artigo Acesso aberto Revisado por pares

E. M. Vitale,

... algebraic categories. As a corollary, we have the Popescu-Gabriel representation theorem for Grothendieck categories.

Tópico(s): Advanced Topics in Algebra

1998 - Elsevier BV | Journal of Pure and Applied Algebra

Artigo Acesso aberto Revisado por pares

Hoa V. Pham, Basanta Bhaduri, Krishnarao Tangella, Catherine Best‐Popescu, Gabriel Popescu,

We demonstrate a real-time blood testing system that can provide remote diagnosis with minimal human intervention in economically challenged areas. Our instrument combines novel advances in label-free optical imaging with parallel computing. Specifically, we use quantitative phase imaging for extracting red blood cell morphology with nanoscale sensitivity and NVIDIA's CUDA programming language to perform real time cellular-level analysis. While the blood smear is translated through focus, our system ...

Tópico(s): Cell Image Analysis Techniques

2013 - Public Library of Science | PLoS ONE

Artigo Acesso aberto Revisado por pares

Mikhail E. Kandel, Daniel Fernandes, Alison Taylor, Haadi M. Shakir, Catherine Best‐Popescu, Gabriel Popescu,

Due to the limitations of fluorescence imaging techniques, the study of intracellular cargo is typically restricted to two-dimensional analyses. To overcome low light levels and the risk of phototoxicity, we employ quantitative phase imaging, a family of full-field imaging techniques that measure the optical path length shift introduced by the specimen. Specifically, we use spatial light interference microscopy (SLIM) to study the transport of mass in whole tomographic volumes and show that a time- ...

Tópico(s): Microfluidic and Bio-sensing Technologies

2017 - Wiley | Cytometry Part A

Artigo Acesso aberto Revisado por pares

Hassaan Majeed, Lihong Ma, Young Jae Lee, Mikhail E. Kandel, Eunjung Min, Woonggyu Jung, Catherine Best‐Popescu, Gabriel Popescu,

Label-free imaging of rapidly moving, sub-diffraction sized structures has important applications in both biology and material science, as it removes the limitations associated with fluorescence tagging. However, unlabeled nanoscale particles in suspension are difficult to image due to their transparency and fast Brownian motion. Here we describe a novel interferometric imaging technique referred to as Magnified Image Spatial Spectrum (MISS) microscopy, which overcomes these challenges. The MISS ...

Tópico(s): Near-Field Optical Microscopy

2018 - Optica Publishing Group | Optics Express

Artigo Acesso aberto Revisado por pares

Mikhail E. Kandel, Michael J. Fanous, Catherine Best‐Popescu, Gabriel Popescu,

As a label-free, nondestructive method, phase contrast is by far the most popular microscopy technique for routine inspection of cell cultures. However, features of interest such as extensions near cell bodies are often obscured by a glow, which came to be known as the halo. Advances in modeling image formation have shown that this artifact is due to the limited spatial coherence of the illumination. Nevertheless, the same incoherent illumination is responsible for superior sensitivity to fine details ...

Tópico(s): Optical measurement and interference techniques

2018 - Optica Publishing Group | Biomedical Optics Express

Artigo Acesso aberto Revisado por pares

Mikhail E. Kandel, Chenfei Hu, Ghazal Naseri Kouzehgarani, Eunjung Min, Kathryn M. Sullivan, Hyunjoon Kong, Jennifer Li, Drew N. Robson, Martha U. Gillette, Catherine Best‐Popescu, Gabriel Popescu,

Abstract Multiple scattering and absorption limit the depth at which biological tissues can be imaged with light. In thick unlabeled specimens, multiple scattering randomizes the phase of the field and absorption attenuates light that travels long optical paths. These obstacles limit the performance of transmission imaging. To mitigate these challenges, we developed an epi-illumination gradient light interference microscope (epi-GLIM) as a label-free phase imaging modality applicable to bulk or opaque ...

Tópico(s): Advanced Fluorescence Microscopy Techniques

2019 - Nature Portfolio | Nature Communications

Artigo Acesso aberto Revisado por pares

Neha Goswami, Yuchen R. He, Yu‐Heng Deng, Chamteut Oh, Nahil Sobh, Enrique Valera, Rashid Bashir, Nahed Ismail, Hyunjoon Kong, Thanh H. Nguyen, Catherine Best‐Popescu, Gabriel Popescu,

Efforts to mitigate the COVID-19 crisis revealed that fast, accurate, and scalable testing is crucial for curbing the current impact and that of future pandemics. We propose an optical method for directly imaging unlabeled viral particles and using deep learning for detection and classification. An ultrasensitive interferometric method was used to image four virus types with nanoscale optical path-length sensitivity. Pairing these data with fluorescence images for ground truth, we trained semantic ...

Tópico(s): Electrical and Bioimpedance Tomography

2021 - Springer Nature | Light Science & Applications

Artigo Acesso aberto Revisado por pares

Cristina Popescu, Gabriel-Adrian Popescu, Alina Lobodan, Raluca Dulamă, Doina Niculescu, Diana Tănase, Mihaela Rădulescu, Violeta Molagic, Cătălin Tilişcan, Liliana Ion, Mirela Cernat, M Dinu, Iulia Caragea, Angelica Teniță, Georgiana Jugănaru, Elisabeta Benea, Victoria Aramă,

Background In the era of broad spectrum antibiotics it is sometimes difficult to choose the best antimicrobial regimens. Because of misuse and abuse of antimicrobial usage, the level of resistance is increasing and sometimes we do not have treatment options. Infectious diseases specialists traditionally have the leadership role in optimal use of antimicrobials. Antimicrobial stewardship represents a worldwide accepted concept in order to preserve currently available antibiotics.

Tópico(s): Bacterial Identification and Susceptibility Testing

2013 - BioMed Central | BMC Infectious Diseases

Artigo Revisado por pares

Florencio Castaño Iglesias, P. Enache, C. Năstăsescu, B. Torrecillas,

... this paper we obtain a general version of GabrielPopescu theorem representing any Grothendieck category A as a ... nous établissons une version généralisée du théorème de GabrielPopescu en représentant toute catégorie de Grothendieck A comme ...

Tópico(s): Rings, Modules, and Algebras

2004 - Elsevier BV | Bulletin des Sciences Mathématiques

Artigo Acesso aberto Revisado por pares

Chris Edwards, Amir Arbabi, Gabriel Popescu, Lynford L. Goddard,

... Zehnder interferometer. Developed by Chris Edwards, Amir Arbabi, Gabriel Popescu, and Lynford Goddard at the University of Illinois ...

Tópico(s): Optical Coatings and Gratings

2012 - Springer Nature | Light Science & Applications

Artigo Acesso aberto Revisado por pares

W. Lowen,

... on u. This is a generalization of the GabrielPopescu theorem, which considers the case where u is ...

Tópico(s): Algebraic structures and combinatorial models

2004 - Elsevier BV | Journal of Pure and Applied Algebra

Artigo Acesso aberto Revisado por pares

Marilena-Brîndușa Zamfirescu, Liviu Ghilencea, M Popescu, Gabriel Cristian Bejan, Ileana Maria Ghiordanescu, Andreea-Catarina Popescu, Saul Myerson, Maria Dorobanţu,

Background: The first admission for acute heart failure with preserved ejection fraction (HFpEF) drastically influences the short-term prognosis. Baseline characteristics may predict repeat hospitalization or death in these patients. Methods: A 103 patient-cohort, admitted for the first acute HFpEF episode, was monitored for six months. Baseline characteristics were recorded and their relation to the primary outcome of heart failure readmission (HFR) and secondary outcome of all-cause mortality was ...

Tópico(s): Mechanical Circulatory Support Devices

2021 - Multidisciplinary Digital Publishing Institute | Diagnostics

Artigo Revisado por pares

Voicu Popescu, Gabriel Bester, Alex Zunger,

Quantum dot-based infrared detectors often involve transitions from confined states of the dot to states above the minimum of the conduction band continuum of the matrix. We discuss the existence of two types of resonant states within this continuum in self-assembled dots: (i) virtual bound states, which characterize square wells even without strain and (ii) strain-induced localized states. The latter emerge due to the appearance of “potential wings” near the dot, related to the curvature of the dots. ...

Tópico(s): Quantum and electron transport phenomena

2009 - American Institute of Physics | Applied Physics Letters

Artigo

Voicu Popescu, Gabriel Bester, Alex Zunger,

Quantum dots (QDs) embedded in a matrix exhibit a coexistence of ``zero-dimensional'' (0D) bound electron and hole states on the dot with ``three-dimensional'' (3D) continuum states of the surrounding matrix. In epitaxial QDs one encounters also ``two-dimensional'' (2D) states of a quantum well-like supporting structure (wetting layer). This coexistence of 0D, 2D, and 3D states leads to interesting electronic consequences explored here using multiband atomistic pseudopotential calculations. We distinguish ...

Tópico(s): Surface and Thin Film Phenomena

2009 - American Physical Society | Physical Review B

Artigo Revisado por pares

Ioan-Iovitz Popescu, Gabriel Altmann, Reinhard Köhler,

Tópico(s): Fractal and DNA sequence analysis

2009 - Springer Science+Business Media | Quality & Quantity

Artigo

Voicu Popescu, Gabriel Bester, M. C. Hanna, Andrew G. Norman, Alex Zunger,

The intermediate-band solar cell (IBSC) concept has been recently proposed to enhance the current gain from the solar spectrum whilst maintaining a large open-circuit voltage. Its main idea is to introduce a partially occupied intermediate band (IB) between the valence band (VB) and conduction band (CB) of the semiconductor absorber, thereby increasing the photocurrent by the additional $\text{VB}\ensuremath{\rightarrow}\text{IB}$ and $\text{IB}\ensuremath{\rightarrow}\text{CB}$ absorptions. The confined ...

Tópico(s): Quantum Dots Synthesis And Properties

2008 - American Physical Society | Physical Review B

Artigo Revisado por pares

Ioan-Iovitz Popescu, Gabriel Altmann,

Abstract Counting word forms one obtains more hapax legomena in highly synthetic languages than in highly analytic ones. We propose an index of analytism based exclusively on mechanical counting of word forms in text.

Tópico(s): Authorship Attribution and Profiling

2008 - Routledge | Journal of Quantitative Linguistics

Revisão Acesso aberto Revisado por pares

Cosmin Popescu, Gabriel Sas, Thomas Blanksvärd, Björn Täljsten,

The purpose of this paper is to review the advances that have been made in the design of monolithic and precast reinforced concrete walls, both with and without openings, subject to eccentrically applied axial loads. Using the results of previous experimental studies, a database was assembled to enable statistical assessment of the reliability of existing design models. Several design aspects are highlighted, including the size and position of openings, and the roles of boundary conditions and geometric ...

Tópico(s): Innovative concrete reinforcement materials

2015 - Elsevier BV | Engineering Structures

Artigo Revisado por pares

Cosmin Popescu, Gabriel Sas, Cristian Sabău, Thomas Blanksvärd,

Old structures are frequently modified to comply with current living standards and/or legislation. Such modifications may include the addition of new windows or doors and paths for ventilation and heating systems, all of which require openings to be cut into structural walls. However, effects of the required openings are not sufficiently understood. Thus, the objective of the work reported here was to analyze openings' effects on the axial strength of large concrete wall panels. Three half-scaled ...

Tópico(s): Structural Behavior of Reinforced Concrete

2016 - American Society of Civil Engineers | Journal of Structural Engineering

Artigo Acesso aberto Revisado por pares

Cristian Sabău, Cosmin Popescu, Gabriel Sas, Jacob Wittrup Schmidt, Thomas Blanksvärd, Björn Täljsten,

The allowable strain in fibre reinforced polymers reinforcement is limited by design codes to avoid debonding. The near-surface mounted (NSM) reinforcement technique has been proven to produce better anchorage behaviour compared to externally bonded reinforcement solutions. However, NSM solutions do not always eliminate debonding issues, with concrete cover detachment (CCD) typically occurring in RC beams strengthened for flexure. This experimental study investigated the efficiency of side mounted ( ...

Tópico(s): Structural Response to Dynamic Loads

2018 - Elsevier BV | Composites Part B Engineering

Artigo Acesso aberto Revisado por pares

Ovidiu Popescu, Gabriel Stan,

In this paper, we generalize some results of Wardowski (Fixed Point Theory Appl. 2012:94, 2012), Cosentino and Vetro (Filomat 28:4, 2014), and Piri and Kumam (Fixed Point Theory Appl. 2014:210, 2014) theories by applying some weaker symmetrical conditions on the self map of a complete metric space and on the mapping F, concerning the contractions defined by Wardowski.

Tópico(s): Fixed Point Theorems Analysis

2019 - Multidisciplinary Digital Publishing Institute | Symmetry

Artigo Revisado por pares

Elvira Popescu, Gabriel Badea,

Tópico(s): Mobile Learning in Education

2020 - IEEE Computer Society | Educational Technology & Society

Artigo Acesso aberto Revisado por pares

Ana-Maria Carla Popescu, Gabriel Ion Tudorache, Bo Peng, Andrew H. Kemp,

A focus of the scientific community is to design network oriented position-based routing protocols and this has resulted in a very high number of algorithms, different in approach and performance and each suited only to particular applications. However, though numerous, very few position-based algorithms have actually been adopted for commercial purposes. This article is a survey of almost 50 position-based routing protocols and it comes as an aid in the implementation of this type of routing in ...

Tópico(s): Indoor and Outdoor Localization Technologies

2022 - Iran University of Science and Technology | International Journal of Communication Networks and Information Security (IJCNIS)

Artigo Acesso aberto Revisado por pares

Romina‐Marina Sima, Mihaela Sulea, Julia Caroline Radosa, Sebastian Findeklee, Bashar Haj Hamoud, Mihai Popescu, Gabriel Petre Gorecki, Anca Bobircă, Florin Bobîrcă, Cătălin Cîrstoveanu, Liana Pleș,

Dysmenorrhea is defined as the presence of painful menstruation, and it affects daily activities in different ways. The aims of this study were to assess the prevalence and management of dysmenorrhea and to determine the impact of dysmenorrhea on the quality of life of medical students.The study conducted was prospective, analytical and observational and was performed between 7 November 2019 and 30 January 2020 in five university centers from Romania. The data was collected using an original questionnaire ...

Tópico(s): Menstrual Health and Disorders

2022 - Multidisciplinary Digital Publishing Institute | Healthcare

Artigo

Cristian‐Mihail Niculae, Eliza Manea, Raluca Jipa, Simona Merișor, Ruxandra Moroti, Șerban Benea, Adriana Hristea, Alina Cristina Neguț, Oana Săndulescu, Anca Streinu‐Cercel, Dana Mărculescu, Magdalena Lorena Andrei, Veronica Ilie, Marcela Popa, Coralia Bleoţu, Mariana Carmen Chifiriuc, Mircea Ioan Popa, Adrian Streinu‐Cercel, Alina Orfanu, Cristina Popescu, Anca Leuștean, Remulus Catană, Anca Negru, Alexandra Badea, Radu Orfanu, Cătălin Tilişcan, Victoria Aramă, Ștefan Sorin Aramă, Constanța-Angelica Vișan, Anca-Cristina Drăgănescu, Anuța Bilaşco, Camelia Kouris, Mădălina Maria Merişescu, Magdalena Vasile, Diana-Maria Slavu, Sabina Vintilă, Endis Osman, Alina Oprea, Sabina Sandu, Monica Luminos, Alina Orfanu, Victoria Aramă, Ştefan Sorin Aramă, Anca Leuștean, Remulus Catană, Anca Negru, Gabriel Adrian Popescu, Cristina Popescu, Ramona Georgiana Stanculete, Ana Vaduva Enoiu, Adelina Raluca Marinescu, Voichița Elena Lăzureanu, Adelina-Raluca Marinescu, Alexandru Crişan, Voichița Elena Lăzureanu, Virgil Musta, Narcisa Nicolescu, Ruxandra Laza, Anca-Ruxandra Negru, Daniela-Ioana Munteanu, Raluca Mihăilescu, Remulus Catană, O Dorobăţ, Alexandru Rafilă, Emilia Căpraru, Marius Niculescu, Rodica Marinescu, Olivera Lupescu, Vlad Predescu, Adrian Streinu-Cercel, Victoria Aramă, Daniela Tălăpan, Ramona Ștefania Popescu, Luminița Bradu, Dragoş Florea, Adrian Streinu‐Cercel, Daniela Anicuta Leca, Elena Bunea, Andra Teodor, Egidia Miftode, Mădălina Maria Merişescu, Gheorghiță Jugulete, Adrian Streinu-Cercel, Dragoş Florea, Monica Luminos, Ramona Ștefania Popescu, Anamaria Dobrotă, Adina Ilie, Liliana Lucia Preoțescu, Adriana Hristea, Raluca Jipa, Nicoleta Irimescu, Irina Panait, Eliza Manea, Simona Merișor, Cristian Niculae, Daniela Tălăpan, Liana Gavriliu, Otilia Elisabeta Benea, Șerban Benea, Alexandru Rafila, O Dorobăţ, Mona Popoiu, Livia Dragonu, Augustin Cupşa, Iulian Diaconescu, Irina Niculescu, Lucian Giubelan, Florentina Dumitrescu, Andreea Cristina Stoian, Camelia Guţă, Simona Puiu, Irina Bunescu, M. Vallée, Ann Huletsky, Dominique K. Boudreau, Ève Bérubé, R. Giroux, Jean Longtin, Yves Longtin, Michel G. Bergeron, Cleo Nicoleta Roșculeț, Dalila-Ana Toma, Catrinel Ciuca, Daniela Tălăpan, Cătălin Apostolescu, Andrei Rogoz, Andrei Stangaciu, Viorica Mitescu, Tudor Vladoiu, Doina Iovănescu, Michaela Oana, Simona Costin, Alina Cristina Neguț, Oana Săndulescu, Adrian Streinu‐Cercel, Maria Magdalena Moțoi, Mircea Ioan Popa, Adrian Streinu-Cercel, Daniela Tălăpan, O Dorobăţ, Mona Popoiu, Alexandru Mihai, Doina Iovănescu, Cleo Roşculeț, Cătălin Apostolescu, Gabriel-Adrian Popescu, Adrian Abagiu, Ruxandra Moroti, Adriana Hristea, Victoria Aramă, Otilia Elisabeta Benea, Mădălina Simoiu, Rodica Bacruban, Adrian Streinu-Cercel, Alexandru Rafilă, O Dorobăţ, Daniela Tălăpan, Alexandru Mihai, Ioana Bădicuț, Mona Popoiu, Alina Maria Borcan, Alexandru Rafila, Gabriel Adrian Popescu, M Hurmuzache, Georgiana Enache, A Ciocan, Mircea Bararu, Mădălina Popazu, Doina Viorica Iovănescu, Cleo Nicoleta Roșculeț, Andrei Rogoz, Cătălin Gabriel Apostolescu, Viorica Mitescu, Tudor Vladoiu, Dalila Toma, Catrinel Ciuca, Laura Iliescu, Georgiana Minzala, Letiția Toma, Mihaela Baciu, Alina Tănase, Carmen Orban, Victor Pântea, Gheorghe Plăcintă, Valentin Cebotarescu, Lilia Cojuhari, Paulina Jimbei, Cristina Popescu, Anca Leuștean, Cristina Dragomirescu, Alina Orfanu, Cristina Murariu, Laurențiu Stratan, Alexandra Badea, Cătălin Tilișcan, Daniela Munteanu, Raluca Năstase, Violeta Molagic, Mihaela Rădulescu, Remulus Catană, Victoria Aramă, Cristina Popescu, Laurențiu Stratan, Remulus Catană, Anca Leuștean, Cristina Dragomirescu, Alexandra Badea, Cristina Murariu, Raluca Năstase, Violeta Molagic, Daniela Munteanu, Cătălin Tilișcan, Mihaela Rădulescu, Alina Orfanu, Ioan Diaconu, Anca Negru, Iulia Bodosca, Violeta Niță, Victoria Aramă, Anca Leuștean, Victoria Aramă, Alina Orfanu, Remulus Catană, Laurențiu Stratan, Cristina Dragomirescu, Cristina Murariu, Alexandra Badea, Cătălin Tilișcan, Daniela Munteanu, Violeta Molagic, Raluca Năstase, Mihaela Rădulescu, Cristina Popescu, Cristina Popescu, Cristina Dragomirescu, Anca Leuștean, Cristina Murariu, Laurențiu Stratan, Alexandra Badea, Remulus Catană, Alina Orfanu, Raluca Mihaela Năstase, Violeta Molagic, Daniela Munteanu, Cătălin Tilișcan, Victoria Aramă, Victoria Aramă, Remulus Catană, Cristina Dragomirescu, Cristina Murariu, Anca Leuștean, Laurențiu Stratan, Alexandra Badea, Alina Orfanu, Anca Negru, Raluca Năstase, Violeta Molagic, Daniela Munteanu, Cătălin Tilișcan, Mihaela Rădulescu, Ioan Diaconu, Violeta Niță, Iulia Bodoșca, Cristina Popescu, Cristina Popescu, Alexandra Badea, Anca Leuștean, Alina Orfanu, Anca Negru, Laurențiu Stratan, Cristina Dragomirescu, Remulus Catană, Cristina Murariu, Violeta Molagic, Raluca Năstase, Cătălin Tilișcan, Daniela Munteanu, Mihaela Rădulescu, Ioan Diaconu, Violeta Niță, Iulia Bodoșca, Victoria Aramă, Cristina Popescu, Alina Orfanu, Anca Leuștean, Alexandra Badea, Laurențiu Stratan, Remulus Catană, Cătălin Tilișcan, Victoria Aramă, Cristina Popescu, Cristina Murariu, Cristina Dragomirescu, Anca Leuștean, Laurențiu Stratan,

... Sorin Aramă, Anca Leuştean, Remulus Catană, Anca Negru, Gabriel Adrian Popescu, Cristina Popescu A6 Whooping cough in a HIV ... Alexandru Mihai, Doina Iovănescu, Cleo Roşculeț, Cătălin Apostolescu, Gabriel-Adrian Popescu, Adrian Abagiu, Ruxandra Moroti-Constantinescu, Adriana Hristea, Victoria ... bacilli in Romania: an analysis and some proposals Gabriel Adrian Popescu A23 Etiological, clinical and therapeutic considerations on 78 ...

BioMed Central

Artigo Acesso aberto Revisado por pares

YongKeun Park, Catherine Best‐Popescu, Ramachandra R. Dasari, Gabriel Popescu,

We present the light scattering properties of individual human red blood cells (RBCs). We show that both the RBC static and dynamic scattering signals are altered by adenosine 5'-triphosphate (ATP)-driven membrane metabolic remodeling. To measure the light scattering signal from individual RBCs, we use diffraction phase microscopy together with a Fourier transform light scattering technique. RBC cytosolic ATPs are both chemically and metabolically depleted, and the corresponding scattering signals ...

Tópico(s): Spectroscopy Techniques in Biomedical and Chemical Research

2011 - SPIE | Journal of Biomedical Optics

Artigo Acesso aberto Revisado por pares

Cristina Mateescu, Anca Mihaela Popescu, Gabriel Lucian Radu, Tatiana Onisei, Adina Elena Răducanu,

Purpose: This study was carried out in order to find a reliable method for the fast detection of adulterated herbal food supplements with sexual enhancement claims. As some herbal products are advertised as "all natural", their "efficiency" is often increased by addition of active pharmaceutical ingredients such as PDE-5 inhibitors, which can be a real health threat for the consumer. Methodes: Adulterants, potentially present in 50 herbal food supplements with sexual improvement claims, were detected ...

Tópico(s): Pesticide Residue Analysis and Safety

2017 - Tabriz University of Medical Sciences | Advanced Pharmaceutical Bulletin

Artigo Revisado por pares

Septimiu Crivei, C. Năstăsescu, Laura Năstăsescu,

... important results. Thus, the Ulmer Theorem, the generalized GabrielPopescu Theorem and the generalized Takeuchi Lemma are all ...

Tópico(s): Rings, Modules, and Algebras

2012 - Elsevier BV | Journal of Pure and Applied Algebra