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Universitatea Națională de Știință și Tehnologie Politehnica București

UniversityBucharest, Romania

Research output, citation impact, and the most-cited recent papers from Universitatea Națională de Știință și Tehnologie Politehnica București (Romania). Aggregated across the NobleBlocks index of 300M+ scholarly works.

Total works
37.6K
Citations
967.2K
h-index
257
i10-index
22.8K
Also known as
POLITEHNICA BucureștiPolytechnic University of BucharestPolytehnica University of BucharestUniversitatea Națională de Știință și Tehnologie Politehnica BucureștiUniversitatea Politehnica din București

Top-cited papers from Universitatea Națională de Știință și Tehnologie Politehnica București

Biomedical Applications of Silver Nanoparticles: An Up-to-Date Overview
Alexandra-Cristina Burdușel, Oana Gherasim, Alexandru Mihai Grumezescu, Laurenţiu Mogoantă +2 more
2018· Nanomaterials1.3Kdoi:10.3390/nano8090681

During the past few years, silver nanoparticles (AgNPs) became one of the most investigated and explored nanotechnology-derived nanostructures, given the fact that nanosilver-based materials proved to have interesting, challenging, and promising characteristics suitable for various biomedical applications. Among modern biomedical potential of AgNPs, tremendous interest is oriented toward the therapeutically enhanced personalized healthcare practice. AgNPs proved to have genuine features and impressive potential for the development of novel antimicrobial agents, drug-delivery formulations, detection and diagnosis platforms, biomaterial and medical device coatings, tissue restoration and regeneration materials, complex healthcare condition strategies, and performance-enhanced therapeutic alternatives. Given the impressive biomedical-related potential applications of AgNPs, impressive efforts were undertaken on understanding the intricate mechanisms of their biological interactions and possible toxic effects. Within this review, we focused on the latest data regarding the biomedical use of AgNP-based nanostructures, including aspects related to their potential toxicity, unique physiochemical properties, and biofunctional behaviors, discussing herein the intrinsic anti-inflammatory, antibacterial, antiviral, and antifungal activities of silver-based nanostructures.

An Overview of Oxidative Stress, Neuroinflammation, and Neurodegenerative Diseases
Daniel Mihai Teleanu, Adelina-Gabriela Niculescu, Iulia Ioana Lungu, Crina Ioana Radu +4 more
2022· International Journal of Molecular Sciences948doi:10.3390/ijms23115938

Oxidative stress has been linked with a variety of diseases, being involved in the debut and/or progress of several neurodegenerative disorders. This review intends to summarize some of the findings that correlate the overproduction of reactive oxygen species with the pathophysiology of Alzheimer's disease, Parkinson's disease, Huntington's disease, and amyotrophic lateral sclerosis. Oxidative stress was also noted to modify the inflammatory response. Even though oxidative stress and neuroinflammation are two totally different pathological events, they are linked and affect one another. Nonetheless, there are still several mechanisms that need to be understood regarding the onset and the progress of neurodegenerative diseases in order to develop efficient therapies. As antioxidants are a means to alter oxidative stress and slow down the symptoms of these neurodegenerative diseases, the most common antioxidants, enzymatic as well as non-enzymatic, have been mentioned in this paper as therapeutic options for the discussed disorders.

Observation of a Centrality-Dependent Dijet Asymmetry in Lead-Lead Collisions at<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:msqrt><mml:msub><mml:mi>s</mml:mi><mml:mi>NN</mml:mi></mml:msub></mml:msqrt><mml:mo>=</mml:mo><mml:mn>2.76</mml:mn><mml:mtext> </mml:mtext><mml:mtext> </mml:mtext><mml:mi>TeV</mml:mi></mml:math>with the ATLAS Detector at the LHC
G. Aad, B. Abbott, J. Abdallah, A. A. Abdelalim +4 more
2010· Physical Review Letters735doi:10.1103/physrevlett.105.252303

By using the ATLAS detector, observations have been made of a centrality-dependent dijet asymmetry in the collisions of lead ions at the Large Hadron Collider. In a sample of lead-lead events with a per-nucleon center of mass energy of 2.76 TeV, selected with a minimum bias trigger, jets are reconstructed in fine-grained, longitudinally segmented electromagnetic and hadronic calorimeters. The transverse energies of dijets in opposite hemispheres are observed to become systematically more unbalanced with increasing event centrality leading to a large number of events which contain highly asymmetric dijets. This is the first observation of an enhancement of events with such large dijet asymmetries, not observed in proton-proton collisions, which may point to an interpretation in terms of strong jet energy loss in a hot, dense medium.

Treatment Strategies for Infected Wounds
Irina Neguț, Valentina Grumezescu, Alexandru Mihai Grumezescu
2018· Molecules724doi:10.3390/molecules23092392

The treatment of skin wounds is a key research domain owing to the important functional and aesthetic role of this tissue. When the skin is impaired, bacteria can soon infiltrate into underlying tissues which can lead to life-threatening infections. Consequently, effective treatments are necessary to deal with such pathological conditions. Recently, wound dressings loaded with antimicrobial agents have emerged as viable options to reduce wound bacterial colonization and infection, in order to improve the healing process. In this paper, we present an overview of the most prominent antibiotic-embedded wound dressings, as well as the limitations of their use. A promising, but still an underrated group of potential antibacterial agents that can be integrated into wound dressings are natural products, especially essential oils. Some of the most commonly used essential oils against multidrug-resistant microorganisms, such as tea tree, St. John's Wort, lavender and oregano, together with their incorporation into wound dressings are presented. In addition, another natural product that exhibits encouraging antibacterial activity is honey. We highlight recent results of several studies carried out by researchers from different regions of the world on wound dressings impregnated with honey, with a special emphasis on Manuka honey. Finally, we highlight recent advances in using nanoparticles as platforms to increase the effect of pharmaceutical formulations aimed at wound healing. Silver, gold, and zinc nanoparticles alone or functionalized with diverse antimicrobial compounds have been integrated into wound dressings and demonstrated therapeutic effects on wounds.

Improving datacenter performance and robustness with multipath TCP
Costin Raiciu, Sébastien Barré, Christopher Pluntke, Adam Greenhalgh +2 more
2011679doi:10.1145/2018436.2018467

The latest large-scale data centers offer higher aggregate bandwidth and robustness by creating multiple paths in the core of the net- work. To utilize this bandwidth requires different flows take different paths, which poses a challenge. In short, a single-path transport seems ill-suited to such networks.

Fabrication and Applications of Microfluidic Devices: A Review
Adelina-Gabriela Niculescu, Cristina Chircov, Alexandra Cătălina Bîrcă, Alexandru Mihai Grumezescu
2021· International Journal of Molecular Sciences634doi:10.3390/ijms22042011

Microfluidics is a relatively newly emerged field based on the combined principles of physics, chemistry, biology, fluid dynamics, microelectronics, and material science. Various materials can be processed into miniaturized chips containing channels and chambers in the microscale range. A diverse repertoire of methods can be chosen to manufacture such platforms of desired size, shape, and geometry. Whether they are used alone or in combination with other devices, microfluidic chips can be employed in nanoparticle preparation, drug encapsulation, delivery, and targeting, cell analysis, diagnosis, and cell culture. This paper presents microfluidic technology in terms of the available platform materials and fabrication techniques, also focusing on the biomedical applications of these remarkable devices.

Combined niche and neutral effects in a microbial wastewater treatment community
Irina Dana Ofiţeru, Mary Lunn, Thomas P. Curtis, George Wells +3 more
2010· Proceedings of the National Academy of Sciences603doi:10.1073/pnas.1000604107

It has long been assumed that differences in the relative abundance of taxa in microbial communities reflect differences in environmental conditions. Here we show that in the economically and environmentally important microbial communities in a wastewater treatment plant, the population dynamics are consistent with neutral community assembly, where chance and random immigration play an important and predictable role in shaping the communities. Using dynamic observations, we demonstrate a straightforward calibration of a purely neutral model and a parsimonious method to incorporate environmental influence on the reproduction (or birth) rate of individual taxa. The calibrated model parameters are biologically plausible, with the population turnover and diversity in the heterotrophic community being higher than for the ammonia oxidizing bacteria (AOB) and immigration into AOB community being relatively higher. When environmental factors were incorporated more of the variance in the observations could be explained but immigration and random reproduction and deaths remained the dominant driver in determining the relative abundance of the common taxa. Consequently we suggest that neutral community models should be the foundation of any description of an open biological system.

Linear electric actuators and generators
Ion Boldea, Syed A. Nasar
1999· IEEE Transactions on Energy Conversion586doi:10.1109/60.790940

Linear electric actuators and generators (LEAGs) are electromagnetic devices which develop directly short-travel progressive (or oscillatory) linear motion. Machine tool sliding tables, pen recorders and free piston power machines are typical industrial applications for LEAGs. Their recent revival in applications in compressors, pumps, electromagnetic valve actuators, active shock absorbers, vibrators, etc. Prompts this review, which presents main LEAGs configurations, their principles of operations, comparative performance evaluation, motion control and existing as well as potential applications.

Observation of Associated Near-Side and Away-Side Long-Range Correlations in<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:msqrt><mml:msub><mml:mi>s</mml:mi><mml:mrow><mml:mi>N</mml:mi><mml:mi>N</mml:mi></mml:mrow></mml:msub></mml:msqrt><mml:mo mathvariant="bold">=</mml:mo><mml:mn>5.02</mml:mn><mml:mtext> </mml:mtext><mml:mtext> </mml:mtext><mml:mi>TeV</mml:mi></mml:math>Proton-Lead Collisions with the ATLAS Detector
G. Aad, T. Abajyan, B. Abbott, J. Abdallah +4 more
2013· Physical Review Letters553doi:10.1103/physrevlett.110.182302

Two-particle correlations in relative azimuthal angle ($\ensuremath{\Delta}\ensuremath{\phi}$) and pseudorapidity ($\ensuremath{\Delta}\ensuremath{\eta}$) are measured in $\sqrt{{s}_{\mathrm{NN}}}=5.02\text{ }\text{ }\mathrm{TeV}$ $p+\mathrm{Pb}$ collisions using the ATLAS detector at the LHC. The measurements are performed using approximately $1\text{ }\text{ }\ensuremath{\mu}{\mathrm{b}}^{\ensuremath{-}1}$ of data as a function of transverse momentum (${p}_{\mathrm{T}}$) and the transverse energy ($\ensuremath{\Sigma}{E}_{\mathrm{T}}^{\mathrm{Pb}}$) summed over $3.1&lt;\ensuremath{\eta}&lt;4.9$ in the direction of the Pb beam. The correlation function, constructed from charged particles, exhibits a long-range ($2&lt;|\ensuremath{\Delta}\ensuremath{\eta}|&lt;5$) ``near-side'' ($\ensuremath{\Delta}\ensuremath{\phi}\ensuremath{\sim}0$) correlation that grows rapidly with increasing $\ensuremath{\Sigma}{E}_{\mathrm{T}}^{\mathrm{Pb}}$. A long-range ``away-side'' ($\ensuremath{\Delta}\ensuremath{\phi}\ensuremath{\sim}\ensuremath{\pi}$) correlation, obtained by subtracting the expected contributions from recoiling dijets and other sources estimated using events with small $\ensuremath{\Sigma}{E}_{\mathrm{T}}^{\mathrm{Pb}}$, is found to match the near-side correlation in magnitude, shape (in $\ensuremath{\Delta}\ensuremath{\eta}$ and $\ensuremath{\Delta}\ensuremath{\phi}$) and $\ensuremath{\Sigma}{E}_{\mathrm{T}}^{\mathrm{Pb}}$ dependence. The resultant $\ensuremath{\Delta}\ensuremath{\phi}$ correlation is approximately symmetric about $\ensuremath{\pi}/2$, and is consistent with a dominant $\mathrm{cos}2\ensuremath{\Delta}\ensuremath{\phi}$ modulation for all $\ensuremath{\Sigma}{E}_{\mathrm{T}}^{\mathrm{Pb}}$ ranges and particle ${p}_{\mathrm{T}}$.

Semi-Markov Processes and Reliability
Nikolaos Limnios, Gheorghe Oprişan
2001· Birkhäuser Boston eBooks542doi:10.1007/978-1-4612-0161-8

At first there was the Markov property. The theory of stochastic processes, which can be considered as an exten sion of probability theory, allows the modeling of the evolution of systems through the

How hard can it be? designing and implementing a deployable multipath TCP
Costin Raiciu, Christoph Paasch, Sébastien Barré, Alan Ford +4 more
2012· Digital Access to Libraries (Université catholique de Louvain (UCL), l'Université de Namur (UNamur) and the Université Saint-Louis (USL-B))536

Networks have become multipath: mobile devices have multiple radio interfaces, datacenters have redundant paths and multihoming is the norm for big server farms. Meanwhile, TCP is still only single-path.\nIs it possible to extend TCP to enable it to support multiple paths for current applications on today’s Internet? The answer is positive. We carefully review the constraints — partly due to various types of middleboxes — that influenced the design of Multipath TCP and show how we handled them to achieve its deployability goals.\nWe report our experience in implementing Multipath TCP in the Linux kernel and we evaluate its performance. Our measurements focus on the algorithms needed to efficiently use paths with different characteristics, notably send and receive buffer tuning and segment reordering. We also compare the performance of our implementation with regular TCP on web servers. Finally, we discuss the lessons learned from designing MPTCP.

Neurotransmitters—Key Factors in Neurological and Neurodegenerative Disorders of the Central Nervous System
Raluca Ioana Teleanu, Adelina-Gabriela Niculescu, Eugenia Roza, Oana Aurelia Vladâcenco +2 more
2022· International Journal of Molecular Sciences536doi:10.3390/ijms23115954

Neurotransmitters are molecules that amplify, transmit, and convert signals in cells, having an essential role in information transmission throughout the nervous system. Hundreds of such chemicals have been discovered in the last century, continuing to be identified and studied concerning their action on brain health. These substances have been observed to influence numerous functions, including emotions, thoughts, memories, learning, and movements. Thus, disturbances in neurotransmitters' homeostasis started being correlated with a plethora of neurological and neurodegenerative disorders. In this respect, the present paper aims to describe the most important neurotransmitters, broadly classified into canonical (e.g., amino acids, monoamines, acetylcholine, purines, soluble gases, neuropeptides) and noncanonical neurotransmitters (e.g., exosomes, steroids, D-aspartic acid), and explain their link with some of the most relevant neurological conditions. Moreover, a brief overview of the recently developed neurotransmitters' detection methods is offered, followed by several considerations on the modulation of these substances towards restoring homeostasis.

Towards a Circular Economy– a Zero Waste Programme for Europe
Dana Corina Deselnicu, Gheorghe Militaru, Viorica Deselnicu, Gabriel Zăinescu +1 more
2018· ICAMS532doi:10.24264/icams-2018.xi.4

This paper presents key elements of the revised waste proposals. From the new waste proposals will benefits the economy, citizens and the environment. Clear rules, common standards and support for the use of more secondary raw materials will create a safe and sustainable supply of raw materials to the industry. This helps create new jobs, supports innovation and boosts competitiveness. Improved waste management rules will reduce landfill and tipping fees. Smarter use of resources is not only good for business, but will also help protect the environment preserve essential resources for current and future generations, and create synergies for industries which most depend on it -such as tourism, agriculture and food manufacturing.

A survey on software architecture analysis methods
Liliana Dobrica, Eila Niemelä
2002· IEEE Transactions on Software Engineering518doi:10.1109/tse.2002.1019479

The purpose of the architecture evaluation of a software system is to analyze the architecture to identify potential risks and to verify that the quality requirements have been addressed in the design. This survey shows the state of the research at this moment, in this domain, by presenting and discussing eight of the most representative architecture analysis methods. The selection of the studied methods tries to cover as many particular views of objective reflections as possible to be derived from the general goal. The role of the discussion is to offer guidelines related to the use of the most suitable method for an architecture assessment process. We will concentrate on discovering similarities and differences between these eight available methods by making classifications, comparisons and appropriateness studies.

Methods of Recycling, Properties and Applications of Recycled Thermoplastic Polymers
Mădălina Elena Grigore
2017· Recycling513doi:10.3390/recycling2040024

This study aims to provide an updated survey of the main thermoplastic polymers in order to obtain recyclable materials for various industrial and indoor applications. The synthesis approach significantly impacts the properties of such materials and these properties in turn have a significant impact on their applications. Due to the ideal properties of the thermoplastic polymers such as corrosion resistance, low density or user-friendly design, the production of plastics has increased markedly over the last 60 years, becoming more used than aluminum or other metals. Also, recycling is one of the most important actions currently available to reduce these impacts and represents one of the most dynamic areas in the plastics industry today.

High Performance Current Controller for Selective Harmonic Compensation in Active Power Filters
Cristian Lascu, Lucian Asiminoaei, Ion Boldea, Frede Blaabjerg
2007· IEEE Transactions on Power Electronics512doi:10.1109/tpel.2007.904060

A new current control scheme for selective harmonic compensation is proposed for shunt active power filters. The method employs an array of resonant current controllers, one for the fundamental, and one for each harmonic, implemented in fundamental reference frame in order to reduce the overall computational effort. The proposed controller design is based on the pole-zero cancellation technique, taking into account the load transfer function at each harmonic frequency. Two design methods are provided, which give controller transfer functions with superior frequency response. The complete current controller is realized as the superposition of all individual harmonic controllers. The frequency response of the entire closed loop control is optimal with respect to filtering objectives, i.e., the system provides good overall stability and excellent selectivity for interesting harmonics. This conclusion is supported by experimental results on a 7.6-kVA laboratory filter, indicating a reduction in current THD factor from 34% to 2%, while the highest harmonic compensated is the 37th harmonic current.

Charged-particle multiplicities in<i>pp</i>interactions measured with the ATLAS detector at the LHC
G. Aad, B. Abbott, J. Abdallah, A. A. Abdelalim +4 more
2011· New Journal of Physics507doi:10.1088/1367-2630/13/5/053033

CERN-LHC. Measurement of inclusive charged particle distributions in proton proton collisions at centre-of-mass energies 0.9, 2.36 and 7 TeV using a single-arm minimum-bias trigger. Distributions of charged particle multiplicity and its dependence on pseudorapidity and transverse momentum are presented from ~190 mub-1 of data at 7 Tev, ~7 mub-1 at 0.9 TeV, and ~0.1 mub-1 at 2.36 GeV. UPDATE 20/05/2016: A wrong point was removed from table 16.

Tumor Angiogenesis and Anti-Angiogenic Strategies for Cancer Treatment
Raluca Ioana Teleanu, Cristina Chircov, Alexandru Mihai Grumezescu, Daniel Mihai Teleanu
2019· Journal of Clinical Medicine497doi:10.3390/jcm9010084

Angiogenesis is the process through which novel blood vessels are formed from pre-existing ones and it is involved in both physiological and pathological processes of the body. Furthermore, tumor angiogenesis is a crucial factor associated with tumor growth, progression, and metastasis. In this manner, there has been a great interest in the development of anti-angiogenesis strategies that could inhibit tumor vascularization. Conventional approaches comprise the administration of anti-angiogenic drugs that target and block the activity of proangiogenic factors. However, as their efficacy is still a matter of debate, novel strategies have been focusing on combining anti-angiogenic agents with chemotherapy or immunotherapy. Moreover, nanotechnology has also been investigated for the potential of nanomaterials to target and release anti-angiogenic drugs at specific sites. The aim of this paper is to review the mechanisms involved in angiogenesis and tumor vascularization and provide an overview of the recent trends in anti-angiogenic strategies for cancer therapy.

Measurement of the azimuthal anisotropy for charged particle production in<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mrow><mml:msqrt><mml:msub><mml:mi>s</mml:mi><mml:mrow><mml:mi>N</mml:mi><mml:mi>N</mml:mi></mml:mrow></mml:msub></mml:msqrt><mml:mo>=</mml:mo><mml:mn>2.76</mml:mn></mml:mrow></mml:math>TeV lead-lead collisions with the ATLAS detector
G. Aad, B. Abbott, J. Abdallah, S. Abdel Khalek +4 more
2012· Physical Review C481doi:10.1103/physrevc.86.014907

Differential measurements of charged particle azimuthal anisotropy are presented for lead-lead collisions at s NN = 2.76 TeV with the ATLAS detector at the LHC, based on an integrated luminosity of approximately 8 b -1 . This anisotropy is characterized via a Fourier expansion of the distribution of charged particles in azimuthal angle relative to the reaction plane, with the coefficients v n denoting the magnitude of the anisotropy. Significant v 2 -v 6 values are obtained as a function of transverse momentum (0.5 < p T < 20 GeV), pseudorapidity (|| < 2.5), and centrality using an event plane method. The v n values for n 3 are found to vary weakly with both and centrality, and their p T dependencies are found to follow an approximate scaling relation,

A Survey on Wearable Technology: History, State-of-the-Art and Current Challenges
Aleksandr Ometov, Viktoriia Shubina, Lucie Klus, Justyna Skibińska +4 more
2021· Computer Networks481doi:10.1016/j.comnet.2021.108074

Technology is continually undergoing a constituent development caused by the appearance of billions new interconnected “things” and their entrenchment in our daily lives. One of the underlying versatile technologies, namely wearables, is able to capture rich contextual information produced by such devices and use it to deliver a legitimately personalized experience. The main aim of this paper is to shed light on the history of wearable devices and provide a state-of-the-art review on the wearable market. Moreover, the paper provides an extensive and diverse classification of wearables, based on various factors, a discussion on wireless communication technologies, architectures, data processing aspects, and market status, as well as a variety of other actual information on wearable technology. Finally, the survey highlights the critical challenges and existing/future solutions.