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Pheochromocytomas and paragangliomas (PPGL) are neuroendocrine tumors characterized by the excessive production of catecholamines. This study aims to describe the clinical characteristics of PPGL cases in Argentina over recent decades. A multicenter retrospective cross-sectional analysis was carried out using a database comprising both pediatric and adult patients with confirmed PPGL diagnoses based on pathological reports. A cohort of 486 patients with PPGL was recruited. Women represent 58.4% of the patients, with a mean age of 38.3 years old at the time of diagnosis and 15.2% of the patients were under the age of 18. Hypertension, as well as classic signs and symptoms, were present in 80.9% of the patients. The adrenal incidentaloma, as a mode of presentation, increased in the last two decades rising from 3.9% (1953-2000) to 21.8% (2001-2022), p<0.001. Most tumors were located within the adrenal glands, accounting 83.0% of the cases, with bilateral occurrences noted in 20.0%. The median tumor size was 4.8cm. Local recurrence and metastases were observed in 10.9% and 12.2%. Out of 412 patients, 87.0% exhibited urinary excretion elevation of catecholamines and/or their metabolites. Furthermore, 148 patients, representing 30.4% of the study population, displayed a distinct genetic profile indicative of hereditary syndromes. The distribution of hereditary syndromes revealed that MEN2, VHL, and PGL4 constituted the most prevalent syndromes. This population-based study, spanning seven decades, offers valuable insights into the demographic and clinical characteristics of PPGL patients in Argentina.
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Neoplasias das Glândulas Suprarrenais , Bases de Dados Factuais , Paraganglioma , Feocromocitoma , Humanos , Feocromocitoma/patologia , Feocromocitoma/epidemiologia , Argentina , Neoplasias das Glândulas Suprarrenais/epidemiologia , Neoplasias das Glândulas Suprarrenais/patologia , Feminino , Masculino , Estudos Retrospectivos , Adulto , Paraganglioma/patologia , Estudos Transversais , Pessoa de Meia-Idade , Adolescente , Adulto Jovem , Criança , Idoso , Recidiva Local de Neoplasia/epidemiologia , Pré-Escolar , Hipertensão/epidemiologiaRESUMO
In this work, we theoretically study the transduction of orbital angular momentum (OAM) l for infrared pump lasers into the THz domain. In the case of optical rectification, the transduction of OAM occurs only through a spin-orbit interaction, with the selection rule on the OAM l=0 valid for any kind of polarization of the pump, which means that there is no transfer of OAM along the propagation axis. In difference frequency generation, the selection rule for the difference Δl between the OAM of the pump fields with linear or circular polarization is l=Δl, whereas l ranges from Δl-2 to Δl+2 in cases of both radial and azimuthal polarization. Moreover, for THz generation in the latter case, the high diffraction obtained with tightly focused pumps yields l tending to Δl±2, while l tends to zero in the opposite case of large pump beams.
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We present here a small-scale liquid helium immersion cryostat with an innovative optical setup suitable to work in long wavelength radiation ranges and under an applied magnetic field. The cryostat is a multi-stage device with several shielding in addition to several optical stages. The system has been designed with an external liquid nitrogen boiler to reduce liquid bubbling. The optical and mechanical properties of the optical elements were calculated and optimized for the designed configuration, while the optical layout has been simulated and optimized among different configurations based on the geometry of the device. The final design has been optimized for low-noise radiation measurements of proximity junction arrays under an applied magnetic field in the wavelength range λ = 250 µm-2500 µm.
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Light can be strongly confined in subwavelength spatial regions through the interaction with plasmons, the collective electronic modes appearing in metals and semiconductors. This confinement, which is particularly important in the terahertz spectral region, amplifies light-matter interaction and provides a powerful mechanism for efficiently generating nonlinear optical phenomena. These effects are particularly relevant in graphene and topological insulators, where massless Dirac fermions show a naturally nonlinear optical behavior in the terahertz range. The strong interaction scenario has been considered so far from the point of view of light. In this Letter, we investigate instead the effect of strong interaction on the plasmon itself. In particular, we will show that Dirac plasmons in Bi_{2}Se_{3} topological insulator are strongly renormalized when excited by high-intensity terahertz radiation by displaying a huge red-shift down to 60% of its characteristic frequency. This opens the road towards tunable terahertz nonlinear optical devices based on topological insulators.
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Hepatitis B virus (HBV) is a main cause of chronic and acute hepatitis. Healthcare workers (HCWs), including medical students and resident doctors, have an occupational risk of HBV infection. The study aimed to evaluate the long-term persistence of protective anti-HBs antibody levels in healthcare students and resident doctors at risk for occupational exposure to HBV at 15 years after primary vaccination course. Further objective was to evaluate the anamnestic response observed in non-seroprotected subjects receiving a booster dose. Data were collected from the clinical documentation filled in during the occupational medical check of medical students and resident doctors undergoing Occupational Health Surveillance by the University of Ferrara. Of the 621 included individuals, 27.7% had an anti-HBs concentration < 10 mIU/mL. Subjects vaccinated during infancy had more frequently a concentration < 10 mIU/mL than those vaccinated during adolescence (42.7% vs 6.9%; p-value < 0.001). Multivariate analysis confirmed the statistical significance of the vaccination age. 94 subjects who had an anti-HBs concentration < 10 mIU/mL received a booster dose. The proportion of subjects who had an anamnestic response was higher in those vaccinated in infancy rather than during adolescence (94.1% vs 77.8% respectively). These findings suggest that the anti-HBs concentration decreases below 10 mIU/mL more frequently in subjects vaccinated during infancy. Immunological memory seems to persist after the decline of the anti-HB titer, as observed in response to a booster dose. In conclusion, vaccinated subjects at increased risk of HBV infection should be monitored and a booster dose administered if anti-HBs titer is below 10 mIU/mL.
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Anticorpos Anti-Hepatite B/imunologia , Vacinas contra Hepatite B/uso terapêutico , Hepatite B/prevenção & controle , Corpo Clínico Hospitalar , Estudantes de Medicina , Adulto , Estudos Transversais , Feminino , Antígenos de Superfície da Hepatite B/imunologia , Humanos , Imunização Secundária , Memória Imunológica , Internato e Residência , Masculino , Saúde Ocupacional , Adulto JovemRESUMO
A correction to this article has been published and is linked from the HTML and PDF versions of this paper. The error has not been fixed in the paper.
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Pheochromocytomas and paragangliomas are rare neuroendocrine tumours associated with high morbidity and mortality. Recognizing the clinical presentation is the first step for diagnosis. Biochemical studies may determine an excess of catecholamines and their metabolites. However, the available tests offer varying diagnosis precision. Computed tomography and magnetic resonance are highly sensitive for locating these tumours. Functional tests are reserved for when metastatic and multifocal disease are suspected. One third of the patients have a germline mutation and many genes are involved in the development of these tumours.
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Neoplasias das Glândulas Suprarrenais/diagnóstico , Paraganglioma/diagnóstico , Feocromocitoma/diagnóstico , Neoplasias das Glândulas Suprarrenais/genética , Neoplasias das Glândulas Suprarrenais/patologia , Mutação em Linhagem Germinativa , Humanos , Imageamento por Ressonância Magnética/métodos , Paraganglioma/genética , Paraganglioma/patologia , Feocromocitoma/genética , Feocromocitoma/patologia , Tomografia Computadorizada por Raios X/métodosRESUMO
We demonstrate that emission of coherent transition radiation by a â¼1 GeV energy-electron beam passing through an Al foil is enhanced in intensity and extended in frequency spectral range, by the energy correlation established along the beam by coherent synchrotron radiation wakefield, in the presence of a proper electron optics in the beam delivery system. Analytical and numerical models, based on experimental electron beam parameters collected at the FERMI free electron laser (FEL), predict transition radiation with two intensity peaks at â¼0.3 THz and â¼1.5 THz, and extending up to 8.5 THz with intensity above 20 dB w.r.t. the main peak. Up to 80-µJ pulse energy integrated over the full bandwidth is expected at the source, and in agreement with experimental pulse energy measurements. By virtue of its implementation in an FEL beam dump line, this work promises dissemination of user-oriented multi-THz beamlines parasitic and self-synchronized to EUV and x-ray FELs.
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Terahertz (THz) radiation is of great interest for a variety of applications, e.g., particle accelerations, spectroscopy investigations of quantum systems, and high-field study of materials. One of the most common laser-based processes to produce THz pulses is optical rectification, which transduces an infrared pump laser to the THz domain (0.1-20 THz). In this work, we propose and theoretically describe a method to characterize the amplitude and phase of the electric field of the pump laser pulse relying on THz generation and detection. We demonstrate with a numerical example how THz radiation can be used as diagnostics to characterize laser pulses with temporal length at the femtosecond level.
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In this paper, an alternative perspective for the generation of millimetric high-gradient resonant plasma waves is discussed. This method is based on the plasma-wave excitation by energetic single-cycle THz pulses whose temporal length is comparable to the plasma wavelength. The excitation regime discussed in this paper is the quasi-nonlinear regime that can be achieved when the normalized vector potential of the driving THz pulse is on the order of unity. To investigate this regime and determine the strength of the excited electric fields, a Particle-In-Cell (PIC) code has been used. It has been found that by exploiting THz pulses with characteristics currently available in laboratory, longitudinal electron plasma waves with electric gradients up to hundreds MV/m can be obtained. The mm-size nature of the resonant plasma wave can be of great utility for an acceleration scheme in which high-brightness electron bunches are injected into the wave to undergo a strong acceleration. The long-size nature of the acceleration bucket with respect to the short length of the electron bunches can be handled in a more robust manner in comparison with the case when micrometric waves are employed.
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Influenza immunization coverage rates remain far below the optimal value recommended by the World Health Organization, even in groups considered at high risk, such as the elderly. A possible explanation for this suboptimal vaccination uptake may be deprivation. A specifically developed local deprivation index was proposed for the classification of residents in the municipality of Ferrara in order to evaluate the characteristics of subjects over 65 years of age who accepted/refused influenza immunization (2010-2015). The variables building this deprivation index were primarily related to demographic aspects, such as age, widow/widower status, education, family composition and housing characteristics. Influenza immunization coverage rates were unsatisfactory in all categories of deprivation. A statistically significant decreasing trend in coverage rates was observed with decreasing deprivation in the general population and in males, but not in females. In addition to factors composing the local deprivation index, being separated, living in a family of three members and independent contractor were features that hindered immunization among very deprived elderly.
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Influenza Humana/prevenção & controle , Aceitação pelo Paciente de Cuidados de Saúde , Pobreza , Cobertura Vacinal , Idoso , Feminino , Humanos , Programas de Imunização , Itália , Masculino , Fatores SocioeconômicosRESUMO
INTRODUCTION: Hospital infections, or "healthcare associated infections" (HAI) represent the most common and serious complications of healthcare. Adoption of safe care practices able to prevent or control the transmission of infections, both in hospitals and in other healthcare settings is crucial. The aim of the study is to assess the awareness about the risk factors and the most effective measures of prevention of HAI in the University of Ferrara nursing school students, giving particular attention to the hand hygiene practices and the use of standard precautions. METHODS: 339 students attending all the three years of course of the same academic year were enrolled. An anonymous questionnaire was administered in order to investigate the knowledge about three specific areas: infections associated with healthcare practices (HAI), standard precautions (SP) and hand hygiene (HH). RESULTS: A sufficient level of knowledge by all the three groups of students was observed only in the SP area. A barely sufficient score was reached only by the third year students with regard to the proper HH. The level of knowledge about HAI was inadequate. CONCLUSIONS: A periodically check of nursing students' knowledge would be advisable in order to fill any gaps, improve training, reduce HAI and increase prevention measures compliance.
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Infecção Hospitalar/prevenção & controle , Conhecimentos, Atitudes e Prática em Saúde , Estudantes de Enfermagem , Feminino , Humanos , Itália , Masculino , Inquéritos e Questionários , Adulto JovemRESUMO
The influence of the Mott physics on the doping-temperature phase diagram of copper oxides represents a major issue that is subject of intense theoretical and experimental effort. Here, we investigate the ultrafast electron dynamics in prototypical single-layer Bi-based cuprates at the energy scale of the O-2pâCu-3d charge-transfer (CT) process. We demonstrate a clear evolution of the CT excitations from incoherent and localized, as in a Mott insulator, to coherent and delocalized, as in a conventional metal. This reorganization of the high-energy degrees of freedom occurs at the critical doping pcr ≈0.16 irrespective of the temperature, and it can be well described by dynamical mean field theory calculations. We argue that the onset of the low-temperature charge instabilities is the low-energy manifestation of the underlying Mottness that characterizes the p < pcr region of the phase diagram. This discovery sets a new framework for theories of charge order and low-temperature phases in underdoped copper oxides.
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We report on an orbital and temperature dependent study of the onset of coherent quasiparticles in V2O3 single crystal. By using polarized infrared spectroscopy we demonstrate that the electronic coherence temperature is strongly orbital dependent, being about 400 K for [Formula: see text] orbitals and 500 K for the [Formula: see text]. This suggests that V2O3 low energy electrodynamics can be described in terms of two electron liquids differently renormalized by electronic correlations.
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After the discovery of Dirac electrons in condensed matter physics, more specifically in graphene and its derivatives, their potentialities in the fields of plasmonics and photonics have been readily recognized, leading to a plethora of applications in active and tunable optical devices. Massless Dirac carriers have been further found in three-dimensional topological insulators. These exotic quantum systems have an insulating gap in the bulk and intrinsic Dirac metallic states at any surface, sustaining not only single-particle excitations but also plasmonic collective modes. In this paper we will review the plasmon excitations in different microstructures patterned on Bi2Se3 topological insulator thin films as measured by terahertz spectroscopy. We discuss the dependence of the plasmon absorption versus the microstructure shape, wavevector, and magnetic field. Finally we will discuss the topological protection of both the Dirac single-particle and plasmon excitations.
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OBJECTIVES: Transversus abdominis plane block is a regional anaesthesia technique that has proven to be effective for postoperative pain reduction in different abdominal surgical procedures. This study evaluated its efficacy on post laparoscopic hysterectomy pain intensity and analgesic consumption. MATERIALS AND METHODS: Randomized controlled trial which included 40 patients scheduled for laparoscopic hysterectomy, enrolled in 2 groups: transversus abdominis plane block+systemic analgesia (Group 1; n=20), versus systemic analgesia (Group 2; n=20). Opioid consumption within the first 24 postoperative hours, pain intensity scores at 60min, 2, 8 and 24h after surgery, adverse events related to systemic analgesia and time to hospital discharge were evaluated and registered. RESULTS: We found no differences between both groups in opioid consumption (10mg vs. 7mg; P=.2) and pain scores (NVS) within the first 24 postoperative hours, at 60min (3 vs. 5; P=.65), 120min (0 vs. 2; P=.15), 8 and 24h (0 vs. 0; P>.50) for the last 2 points in time analysed. Adverse events related to medication and time to hospital discharge showed similar results. CONCLUSIONS: Adding a transversus abdominis plane block technique to opioid PCA does not seem to improve postoperative pain management in laparoscopic hysterectomy. Patient preparation time and costs could be incremented and complications (although rare) related to the technique could appear.
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Histerectomia/métodos , Laparoscopia , Bloqueio Nervoso/métodos , Dor Pós-Operatória/prevenção & controle , Ultrassonografia de Intervenção , Músculos Abdominais/diagnóstico por imagem , Adulto , Feminino , Humanos , Pessoa de Meia-Idade , Método Simples-Cego , Resultado do TratamentoRESUMO
STUDY DESIGN: This single-masked, randomized and six-month clinical intervention trial including two study groups was planned to evaluate the efficacy of maintenance treatment with glycine powder on the periodontal health of peri-implant tissues. METHODS: A total of 46 patients with partial or total edentulism, carrying a total of 88 implants, were assigned either to an air abrasive with the glycine powder treatment group (AAD) or to a manual debridement and clorexidine administration treatment group (MDA). Clinical data were collected before treatment and at 3 and 6 months after the treatment. Plaque index (PI), bleeding index (BOP), probing depth (PD), clinical attachment level (CAL) and bleeding score (BS) were analysed. RESULTS: After 3 months, AAD treatment statistically significantly improved BS (P < 0.05); at 6 months, AAD treatment statistically significantly improved indexes PD, PI, BOP and BS (P < 0.05). In addition, the AAD treatment proved to be more effective than MDA in maintaining the peri-implant health of PD at three and 6 months, and of PI at 6 months (P < 0.05). There were no significant changes of CAL in both groups, and all the indexes remained within the physiological levels. CONCLUSIONS: Within the limits of the study, treatment with glycine seems appropriate in the maintenance of peri-implant health and more effective than the traditional treatment with plastic curette and chlorhexidine.
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Abrasão Dental por Ar/métodos , Anti-Infecciosos Locais/uso terapêutico , Clorexidina/uso terapêutico , Implantes Dentários , Glicina/uso terapêutico , Mucosite/prevenção & controle , Peri-Implantite/prevenção & controle , Desbridamento Periodontal/métodos , Índice de Placa Dentária , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Índice Periodontal , Pós , Resultado do TratamentoRESUMO
Using angle resolved photoemission spectroscopy, we report the first band dispersions and distinct features of the bulk Fermi surface (FS) in the paramagnetic metallic phase of the prototypical metal-insulator transition material V_{2}O_{3}. Along the c axis we observe both an electron pocket and a triangular holelike FS topology, showing that both V 3d a_{1g} and e_{g}^{π} states contribute to the FS. These results challenge the existing correlation-enhanced crystal field splitting theoretical explanation for the transition mechanism and pave the way for the solution of this mystery.
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The non-equilibrium control of emergent phenomena in solids is an important research frontier, encompassing effects such as the optical enhancement of superconductivity. Nonlinear excitation of certain phonons in bilayer copper oxides was recently shown to induce superconducting-like optical properties at temperatures far greater than the superconducting transition temperature, Tc (refs 4-6). This effect was accompanied by the disruption of competing charge-density-wave correlations, which explained some but not all of the experimental results. Here we report a similar phenomenon in a very different compound, K3C60. By exciting metallic K3C60 with mid-infrared optical pulses, we induce a large increase in carrier mobility, accompanied by the opening of a gap in the optical conductivity. These same signatures are observed at equilibrium when cooling metallic K3C60 below Tc (20 kelvin). Although optical techniques alone cannot unequivocally identify non-equilibrium high-temperature superconductivity, we propose this as a possible explanation of our results.
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We present an experimental and theoretical study exploring surface effects on the evolution of the metal-insulator transition in the model Mott-Hubbard compound Cr-doped V{2}O{3}. We find a microscopic domain formation that is clearly affected by the surface crystallographic orientation. Using scanning photoelectron microscopy and x-ray diffraction, we find that surface defects act as nucleation centers for the formation of domains at the temperature-induced isostructural transition and favor the formation of microscopic metallic regions. A density-functional theory plus dynamical mean-field theory study of different surface terminations shows that the surface reconstruction with excess vanadyl cations leads to doped, and hence more metallic, surface states, which explains our experimental observations.