N. Verga | University of Medicine and Pharmacy "Carol Davila" Bucharest (original) (raw)
Papers by N. Verga
The construction of the high power laser, ELI (150 J, 10 PW, 15 fs, 10 23 W/cm 2 ), on Magurele P... more The construction of the high power laser, ELI (150 J, 10 PW, 15 fs, 10 23 W/cm 2 ), on Magurele Platform induced the idea of its application for the generation of ion beams (protons and carbon ions) with the characteristics necessary for the treatment of malign tumors. Applying the theoretical physical basis, the simulations and experiments of the Radiation Pressure Acceleration for the generation of hadrons beam (50-250 MeV) and of the carbon ions (100-450 MeV/u), this article presents the physical parameters of such beams that may represent a large starting basis for optimizing their values for an entire domain of energies in function of the today existing technology in the field of ultra-relativistic lasers.
Romanian Journal of Physics, 2000
Romanian Reports on Physics
An analytical protocol for the identification of natural dyes in historic textiles by LC-MS and L... more An analytical protocol for the identification of natural dyes in historic textiles by LC-MS and LC-MS/MS was recently developed for the first time in Romania. The present study discusses the application of this approach in the identification of dyes and biological sources in very low amounts of fibers from textiles in local col lections
Computer Physics Communications, 2022
Residual radioactivity following the charged particle irradiations of biomedical materials was me... more Residual radioactivity following the charged particle irradiations of biomedical materials was measured with a high resolution HPGe spectrometer. Proton and 12 C ion beams delivered by the Bucharest FN Tandem Van de Graaff accelerator bombarded bone and artificial heart valve samples at the beam energies comparable with those reached in hadron therapy near the Bragg peak region. Energies, relative intensities and decay curves of the delayed gamma rays following irradiation are reported in the present work. Statistical model calculations for all possible nuclear reactions likely to occur in these experiments were performed by using Talys 1.0 and Cascade codes. These results provide new spectro metric data relevant for the study of the potential late radiation effects from particle radiation exposures in medical therapy.
The delimitation of the unit volume and their reference, their geographically position where the ... more The delimitation of the unit volume and their reference, their geographically position where the ELF effects analysis is performed. The map of natural CEM, added and differentiated function of the local architecture. The ascertainment of levels of the basal artificial electromagnetic charge and of its variation, the personal characteristics, the human groups from the subject make part and of the types of relationships, the local characteristics of the biosphere and its organization, hierarchy, fixed and transitory states of the alive systems and inanimate which included also the subject who is analyzed. Direct local effect, the individual effect included into volume unit and resulted in time unit, effects of addition the dosimetry of the effects. The interpretation follows if these exist clinical chronic effects, the effects of the action and the reaction at these effects on different levels on the point of view of the biological channel. The research is referred at witness zone and...
The present work describes an extremely sensitive apparatus based upon laser photoacoustic spectr... more The present work describes an extremely sensitive apparatus based upon laser photoacoustic spectroscopy (LPAS) methods which can be used for the optical detection of breath ethylene concentration at patients treated by radiotherapy. We analyzed the breath air from patients, subjected to radiation treatment with a high dose fraction, depending on the cancer type and we have found out that patients treated by external radiotherapy suffer a slight increase in the generation of oxidants; however, in accordance with the clinical practice, this increase is sufficient to assess the body response to the treatment: the smaller the increase, the higher the radio-resistivity developed by the patient. With the relevant characteristics of high sensitivity and specificity, LPAS holds a great potential for medical diagnostics and future steps are to be taken in order to bring this method near the patient bad.
This paper presents the 2D, 3D absorbed dose distributions and isodose distributions obtained by ... more This paper presents the 2D, 3D absorbed dose distributions and isodose distributions obtained by the isodensitometric method for the determination of radiation field characteristics used together with sundries filters, in mammography. Thus the next filters: Cu (copper), Al (aluminum) and Th (thorium), with different thicknesses and having the role to attenuate the high energy photons were used. To obtain the dose distributions, the film densitometer from MULTIDATA System – USA, outfitted with RTD4 software – 5.2 version, was used. Future experiments will include mammography investigations showing malign and benign tumors, and having blackening density values and tumor volume penumbra, will be made differentiations between both types of above mentioned tumors.
Computer Physics Communications
Accelerated proton radiotherapy of tumors and ocu lar adnexa is required in addition to brachythe... more Accelerated proton radiotherapy of tumors and ocu lar adnexa is required in addition to brachytherapy as a valuable tool in the destruction of these tumors and preservation of vision. The survival up to 5 years without the tumor may reach values as high as 90%. Although medical needs require it, Romania does not have this feature, which is why this article is trying to suggest a pl an of medical feasibility, an organizational and technological plan that could be implemented in collaboration with organizations and companies from European Community. In this way, it is the present proposal to use the existing cyclotron, TR-19, to g enerate a beam of protons of 19MeV and, with a sufficient intensity, to provide a line ar accelerator of protons the proton beam sufficiently accelerated to 90-120MeV to be used in the treatment of eye tumors. This project was originally proposed by the Italian Foundation for dissemination of the hadrontherapy, TERA, who called the hybrid cyclotron-LIBO, Cyc...
In this paper are presented our research about the magnetic nanoparticles with potential applicat... more In this paper are presented our research about the magnetic nanoparticles with potential applications in malignant tumors diagnostic: cobalt nanoparticles, cobalt-nickel nanoparticles and mixed oxide particles, i.e. magnetite nanoparticles. Cobalt and nickelcobalt nanoparticles have been prepared by co-reducing the corresponding salts. The reduction methods yield a dispersion of nanocrystals in liquids and need a ligand shell or a capping layer to prevent aggregation. The particles of magnetite were prepared by boiling in reflux of a mixture formed by γ-Fe2O3 and Fe(II) salt. The surfaces of magnetite nanoparticles were encapsulated by polymer, polyvinylpyrrolidone (PVP), and a saccharide (used for transportation the magnetic nanocomposite to malignant cells) [22]. TEM examination shows the average sizes of NiCo particles, 5-10nm and the average sizes of Co particles 2-5 nm. Magnetic measurements of nanoparticles were performed at room temperature using Vibrating Sample Magnetometer...
The laser beam (10 PW, 15 fs, 150 J, 10 23 W/cm 2 ) generated by APOLLON Laser System, now under ... more The laser beam (10 PW, 15 fs, 150 J, 10 23 W/cm 2 ) generated by APOLLON Laser System, now under construction on Magurele Platform near Bucharest may also be applied in radiotherapy. Starting from this potential application, location of malign tumors in patient may be situated, e.g., superficial (i 5 cm), semi-deep (510 cm) and profound (>10-40 cm). This paper presents the main physical parameters of a research project for a therapy based on hadrons controlled by laser, for the treatment of superficial and semi-deep tumors. Energies required for pin-pointing the depth of such tumors are 50117 MeV for protons and 100–216 MeV/u for carbon ions. Hadron beams with such energies can be generated by the mechanism Radiation Pressure Acceleration (RPA). Besides, the control systems to provide the daily absorbed dose from the direct and indirect ionizing radiation at the level of the malign tumor of 2 Gy in 1 or 2 minutes with expanded uncertainty of 3 % are presented.
A biological insight into cancer disease is presented. A general view to the cause of cancer at c... more A biological insight into cancer disease is presented. A general view to the cause of cancer at cellular level is given to the reader. Various stages of cancer tumor growth and spread are studied and the physical-biological parameters which might be considered in development of a physical model of cancer tumor are presented. It is concluded that at prevascular stage of tumor growth, the general rule of conservation of energy leads to the same growth curve as many other living organisms.
The energies recommended by IAEA TRS 398 for therapeutic hadron beams range from 50 to 250 MeV fo... more The energies recommended by IAEA TRS 398 for therapeutic hadron beams range from 50 to 250 MeV for protons and from 100 to 450 MeV/u for carbon ions. At present such energies are supplied by conventional cyclotron, synchrocyclotron, synchrotron and linac type accelerators. As an alternative to conventional accelerator beams, laser-driven carbon ion/proton therapy beams have been developed. The parameter which characterizes the interaction of the clinical particle beams with the target is represented by the absorbed dose in the tumors. This paper presents a procedure for measuring the electric charge with ionization chambers as to determine the absorbed dose in clinical hadron beams.
The Optical Coherence Tomography (OCT) is an emerging imaging technique with applications in medi... more The Optical Coherence Tomography (OCT) is an emerging imaging technique with applications in medicine and biomedical optics. OCT is capable of analyzing internal localized microstructures and obtaining high-resolution crosssectional images by backscattered light echo analyze. With resolutions of 1-15 μm, one or two orders of magnitude finer than conventional ultrasound, the OCT is improving the small body imaging techniques. The OCT is mostly a near infrared based analysis technique. The design of OCT systems is based on a Michelson interferometer coupled with a low coherence light source. One arm of the interferometer emits a directed beam scanning the sample. OCT imaging engines usually employ time domain detection using a reference delay arm in order to perform the interferometry. The development of high speed diffraction grating scanners enabled OCT systems to achieve imaging speeds of several thousand axial scans per second and also video rate imaging. A generic OCT system uses...
Residual radioactivity following the charged particle irradiations of biomedical materials was me... more Residual radioactivity following the charged particle irradiations of biomedical materials was measured with a high resolution HPGe spectrometer. Proton and 12 C ion beams delivered by the Bucharest FN Tandem Van de Graaff accelerator bombarded bone and artificial heart valve samples at the beam energies comparable with those reached in hadron therapy near the Bragg peak region. Energies, relative intensities and decay curves of the delayed gamma rays following irradiation are reported in the present work. Statistical model calculations for all possible nuclear reactions likely to occur in these experiments were performed by using Talys 1.0 and Cascade codes. These results provide new spectrometric data relevant for the study of the potential late radiation effects from particle radiation exposures in medical therapy.
Romanian Reports on Physics
An analytical protocol for the identification of natural dyes in historic textiles by LC-MS and L... more An analytical protocol for the identification of natural dyes in historic textiles by LC-MS and LC-MS/MS was recently developed for the first time in Romania. The present study discusses the application of this approach in the identification of dyes and biological sources in very low amounts of fibers from textiles in local col lections
Sensors
In this paper, we present our system for the RSNA Intracranial Hemorrhage Detection challenge, wh... more In this paper, we present our system for the RSNA Intracranial Hemorrhage Detection challenge, which is based on the RSNA 2019 Brain CT Hemorrhage dataset. The proposed system is based on a lightweight deep neural network architecture composed of a convolutional neural network (CNN) that takes as input individual CT slices, and a Long Short-Term Memory (LSTM) network that takes as input multiple feature embeddings provided by the CNN. For efficient processing, we consider various feature selection methods to produce a subset of useful CNN features for the LSTM. Furthermore, we reduce the CT slices by a factor of 2×, which enables us to train the model faster. Even if our model is designed to balance speed and accuracy, we report a weighted mean log loss of 0.04989 on the final test set, which places us in the top 30 ranking (2%) from a total of 1345 participants. While our computing infrastructure does not allow it, processing CT slices at their original scale is likely to improve p...
The construction of the high power laser, ELI (150 J, 10 PW, 15 fs, 10 23 W/cm 2 ), on Magurele P... more The construction of the high power laser, ELI (150 J, 10 PW, 15 fs, 10 23 W/cm 2 ), on Magurele Platform induced the idea of its application for the generation of ion beams (protons and carbon ions) with the characteristics necessary for the treatment of malign tumors. Applying the theoretical physical basis, the simulations and experiments of the Radiation Pressure Acceleration for the generation of hadrons beam (50-250 MeV) and of the carbon ions (100-450 MeV/u), this article presents the physical parameters of such beams that may represent a large starting basis for optimizing their values for an entire domain of energies in function of the today existing technology in the field of ultra-relativistic lasers.
Romanian Journal of Physics, 2000
Romanian Reports on Physics
An analytical protocol for the identification of natural dyes in historic textiles by LC-MS and L... more An analytical protocol for the identification of natural dyes in historic textiles by LC-MS and LC-MS/MS was recently developed for the first time in Romania. The present study discusses the application of this approach in the identification of dyes and biological sources in very low amounts of fibers from textiles in local col lections
Computer Physics Communications, 2022
Residual radioactivity following the charged particle irradiations of biomedical materials was me... more Residual radioactivity following the charged particle irradiations of biomedical materials was measured with a high resolution HPGe spectrometer. Proton and 12 C ion beams delivered by the Bucharest FN Tandem Van de Graaff accelerator bombarded bone and artificial heart valve samples at the beam energies comparable with those reached in hadron therapy near the Bragg peak region. Energies, relative intensities and decay curves of the delayed gamma rays following irradiation are reported in the present work. Statistical model calculations for all possible nuclear reactions likely to occur in these experiments were performed by using Talys 1.0 and Cascade codes. These results provide new spectro metric data relevant for the study of the potential late radiation effects from particle radiation exposures in medical therapy.
The delimitation of the unit volume and their reference, their geographically position where the ... more The delimitation of the unit volume and their reference, their geographically position where the ELF effects analysis is performed. The map of natural CEM, added and differentiated function of the local architecture. The ascertainment of levels of the basal artificial electromagnetic charge and of its variation, the personal characteristics, the human groups from the subject make part and of the types of relationships, the local characteristics of the biosphere and its organization, hierarchy, fixed and transitory states of the alive systems and inanimate which included also the subject who is analyzed. Direct local effect, the individual effect included into volume unit and resulted in time unit, effects of addition the dosimetry of the effects. The interpretation follows if these exist clinical chronic effects, the effects of the action and the reaction at these effects on different levels on the point of view of the biological channel. The research is referred at witness zone and...
The present work describes an extremely sensitive apparatus based upon laser photoacoustic spectr... more The present work describes an extremely sensitive apparatus based upon laser photoacoustic spectroscopy (LPAS) methods which can be used for the optical detection of breath ethylene concentration at patients treated by radiotherapy. We analyzed the breath air from patients, subjected to radiation treatment with a high dose fraction, depending on the cancer type and we have found out that patients treated by external radiotherapy suffer a slight increase in the generation of oxidants; however, in accordance with the clinical practice, this increase is sufficient to assess the body response to the treatment: the smaller the increase, the higher the radio-resistivity developed by the patient. With the relevant characteristics of high sensitivity and specificity, LPAS holds a great potential for medical diagnostics and future steps are to be taken in order to bring this method near the patient bad.
This paper presents the 2D, 3D absorbed dose distributions and isodose distributions obtained by ... more This paper presents the 2D, 3D absorbed dose distributions and isodose distributions obtained by the isodensitometric method for the determination of radiation field characteristics used together with sundries filters, in mammography. Thus the next filters: Cu (copper), Al (aluminum) and Th (thorium), with different thicknesses and having the role to attenuate the high energy photons were used. To obtain the dose distributions, the film densitometer from MULTIDATA System – USA, outfitted with RTD4 software – 5.2 version, was used. Future experiments will include mammography investigations showing malign and benign tumors, and having blackening density values and tumor volume penumbra, will be made differentiations between both types of above mentioned tumors.
Computer Physics Communications
Accelerated proton radiotherapy of tumors and ocu lar adnexa is required in addition to brachythe... more Accelerated proton radiotherapy of tumors and ocu lar adnexa is required in addition to brachytherapy as a valuable tool in the destruction of these tumors and preservation of vision. The survival up to 5 years without the tumor may reach values as high as 90%. Although medical needs require it, Romania does not have this feature, which is why this article is trying to suggest a pl an of medical feasibility, an organizational and technological plan that could be implemented in collaboration with organizations and companies from European Community. In this way, it is the present proposal to use the existing cyclotron, TR-19, to g enerate a beam of protons of 19MeV and, with a sufficient intensity, to provide a line ar accelerator of protons the proton beam sufficiently accelerated to 90-120MeV to be used in the treatment of eye tumors. This project was originally proposed by the Italian Foundation for dissemination of the hadrontherapy, TERA, who called the hybrid cyclotron-LIBO, Cyc...
In this paper are presented our research about the magnetic nanoparticles with potential applicat... more In this paper are presented our research about the magnetic nanoparticles with potential applications in malignant tumors diagnostic: cobalt nanoparticles, cobalt-nickel nanoparticles and mixed oxide particles, i.e. magnetite nanoparticles. Cobalt and nickelcobalt nanoparticles have been prepared by co-reducing the corresponding salts. The reduction methods yield a dispersion of nanocrystals in liquids and need a ligand shell or a capping layer to prevent aggregation. The particles of magnetite were prepared by boiling in reflux of a mixture formed by γ-Fe2O3 and Fe(II) salt. The surfaces of magnetite nanoparticles were encapsulated by polymer, polyvinylpyrrolidone (PVP), and a saccharide (used for transportation the magnetic nanocomposite to malignant cells) [22]. TEM examination shows the average sizes of NiCo particles, 5-10nm and the average sizes of Co particles 2-5 nm. Magnetic measurements of nanoparticles were performed at room temperature using Vibrating Sample Magnetometer...
The laser beam (10 PW, 15 fs, 150 J, 10 23 W/cm 2 ) generated by APOLLON Laser System, now under ... more The laser beam (10 PW, 15 fs, 150 J, 10 23 W/cm 2 ) generated by APOLLON Laser System, now under construction on Magurele Platform near Bucharest may also be applied in radiotherapy. Starting from this potential application, location of malign tumors in patient may be situated, e.g., superficial (i 5 cm), semi-deep (510 cm) and profound (>10-40 cm). This paper presents the main physical parameters of a research project for a therapy based on hadrons controlled by laser, for the treatment of superficial and semi-deep tumors. Energies required for pin-pointing the depth of such tumors are 50117 MeV for protons and 100–216 MeV/u for carbon ions. Hadron beams with such energies can be generated by the mechanism Radiation Pressure Acceleration (RPA). Besides, the control systems to provide the daily absorbed dose from the direct and indirect ionizing radiation at the level of the malign tumor of 2 Gy in 1 or 2 minutes with expanded uncertainty of 3 % are presented.
A biological insight into cancer disease is presented. A general view to the cause of cancer at c... more A biological insight into cancer disease is presented. A general view to the cause of cancer at cellular level is given to the reader. Various stages of cancer tumor growth and spread are studied and the physical-biological parameters which might be considered in development of a physical model of cancer tumor are presented. It is concluded that at prevascular stage of tumor growth, the general rule of conservation of energy leads to the same growth curve as many other living organisms.
The energies recommended by IAEA TRS 398 for therapeutic hadron beams range from 50 to 250 MeV fo... more The energies recommended by IAEA TRS 398 for therapeutic hadron beams range from 50 to 250 MeV for protons and from 100 to 450 MeV/u for carbon ions. At present such energies are supplied by conventional cyclotron, synchrocyclotron, synchrotron and linac type accelerators. As an alternative to conventional accelerator beams, laser-driven carbon ion/proton therapy beams have been developed. The parameter which characterizes the interaction of the clinical particle beams with the target is represented by the absorbed dose in the tumors. This paper presents a procedure for measuring the electric charge with ionization chambers as to determine the absorbed dose in clinical hadron beams.
The Optical Coherence Tomography (OCT) is an emerging imaging technique with applications in medi... more The Optical Coherence Tomography (OCT) is an emerging imaging technique with applications in medicine and biomedical optics. OCT is capable of analyzing internal localized microstructures and obtaining high-resolution crosssectional images by backscattered light echo analyze. With resolutions of 1-15 μm, one or two orders of magnitude finer than conventional ultrasound, the OCT is improving the small body imaging techniques. The OCT is mostly a near infrared based analysis technique. The design of OCT systems is based on a Michelson interferometer coupled with a low coherence light source. One arm of the interferometer emits a directed beam scanning the sample. OCT imaging engines usually employ time domain detection using a reference delay arm in order to perform the interferometry. The development of high speed diffraction grating scanners enabled OCT systems to achieve imaging speeds of several thousand axial scans per second and also video rate imaging. A generic OCT system uses...
Residual radioactivity following the charged particle irradiations of biomedical materials was me... more Residual radioactivity following the charged particle irradiations of biomedical materials was measured with a high resolution HPGe spectrometer. Proton and 12 C ion beams delivered by the Bucharest FN Tandem Van de Graaff accelerator bombarded bone and artificial heart valve samples at the beam energies comparable with those reached in hadron therapy near the Bragg peak region. Energies, relative intensities and decay curves of the delayed gamma rays following irradiation are reported in the present work. Statistical model calculations for all possible nuclear reactions likely to occur in these experiments were performed by using Talys 1.0 and Cascade codes. These results provide new spectrometric data relevant for the study of the potential late radiation effects from particle radiation exposures in medical therapy.
Romanian Reports on Physics
An analytical protocol for the identification of natural dyes in historic textiles by LC-MS and L... more An analytical protocol for the identification of natural dyes in historic textiles by LC-MS and LC-MS/MS was recently developed for the first time in Romania. The present study discusses the application of this approach in the identification of dyes and biological sources in very low amounts of fibers from textiles in local col lections
Sensors
In this paper, we present our system for the RSNA Intracranial Hemorrhage Detection challenge, wh... more In this paper, we present our system for the RSNA Intracranial Hemorrhage Detection challenge, which is based on the RSNA 2019 Brain CT Hemorrhage dataset. The proposed system is based on a lightweight deep neural network architecture composed of a convolutional neural network (CNN) that takes as input individual CT slices, and a Long Short-Term Memory (LSTM) network that takes as input multiple feature embeddings provided by the CNN. For efficient processing, we consider various feature selection methods to produce a subset of useful CNN features for the LSTM. Furthermore, we reduce the CT slices by a factor of 2×, which enables us to train the model faster. Even if our model is designed to balance speed and accuracy, we report a weighted mean log loss of 0.04989 on the final test set, which places us in the top 30 ranking (2%) from a total of 1345 participants. While our computing infrastructure does not allow it, processing CT slices at their original scale is likely to improve p...