1,638 results on '"Lapa,P."'
Search Results
152. PB1910: TELAGLENASTAT (CB-839) IN MONOTHERAPY AND IN COMBINATION WITH EPIGENETIC MODULATORS OR IBRUTINIB INDUCES CELL DEATH IN CHRONIC LYMPHOCYTIC LEUKEMIA CELLS
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Joana Jorge, Hugo Santiago, Beatriz Constantino, Maria Inês Costa, Beatriz Lapa, Raquel Alves, Ana Cristina Gonçalves, and Ana Bela Sarmento-Ribeiro
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Diseases of the blood and blood-forming organs ,RC633-647.5 - Published
- 2023
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153. PB1908: NRF2 INHIBITION IN COMBINATION WITH IBRUTINIB IN THE TREATMENT OF CHRONIC LYMPHOCYTIC LEUKEMIA– AN IN VITRO STUDY
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Joana Jorge, Beatriz Constantino, Hugo Santiago, Maria Inês Costa, Beatriz Lapa, Raquel Alves, Ana Cristina Gonçalves, and Ana Bela Sarmento-Ribeiro
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Diseases of the blood and blood-forming organs ,RC633-647.5 - Published
- 2023
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154. PB1719: NIRAPARIB IN B-CELL LYMPHOID MALIGNANCIES: EXPLORING SYNTHETIC LETHALITY AS TARGET FOR THERAPY
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Beatriz Lapa, Ana Patrícia Portelinha, Maria Inês Costa, Joana Jorge, Raquel Alves, Ana Bela Sarmento-Ribeiro, and Ana Cristina Gonçalves
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Diseases of the blood and blood-forming organs ,RC633-647.5 - Published
- 2023
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155. Níveis de atividade física em Fisioterapeutas
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Maria João Figueiredo, Maria da Lapa Capacete Rosado, and Cláudia Ribeiro da Silva
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Atividade Física ,Fisioterapeutas ,IPAQ-SF ,Recomendações OMS ,Physical activity ,Physiotherapists ,Medicine - Abstract
Introdução: Os baixos níveis de atividade física (AF) são um problema de saúde pública. Apesar da evidência dos benefícios da AF para a saúde, estudos mostram que a população portuguesa não é suficientemente ativa para beneficiar a sua saúde. Os profissionais de saúde, incluindo os Fisioterapeutas, têm um papel importante a desempenhar na promoção da AF aos seus pacientes. Se os Fisioterapeutas Portugueses forem chamados a atuar como especialistas em AF, deve-se primeiro determinar se eles lideram pelo exemplo. Objetivo: Avaliar os níveis de AF dos Fisioterapeutas Portugueses de acordo com as mais recentes recomendações da OMS. Métodos: Foi distribuído e aplicado um questionário online por um período de 6 meses, composto por uma ficha de caracterização de dados sociodemográficos e pelo IPAQ-SF. Obteve-se uma amostra composta por 553 Fisioterapeutas. Resultados: Os resultados do IPAQ-SF revelaram alto nível de AF (56,8%), moderado nível de AF (31,5%) e baixo nível de AF (11,8%). Com relação à análise dos METS AF, pudemos observar que os METS AF vigorosa tiveram uma média maior de 2413,15 (DP=4201,411), seguido dos METS AF moderada com média de 1857,91 (DP=2930,073) e, por fim, os METS associado à caminhada com média de 1635,54 (DP=2841,805). Conclusão: Verificou-se que os níveis de AF dos Fisioterapeutas Portugueses são elevados e que 88,3% da amostra cumprem as recomendações da OMS para AF. Os Fisioterapeutas Portugueses podem estar numa posição de liderança pelo exemplo que dão na promoção da AF regular aos seus pacientes.
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- 2023
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156. Congenital cutaneous candidiasis in a term newborn
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Teresa Botelho, Inês Gameiro, Maria Relvas, João Teixeira, Mariana Batista, Ana Rodrigues-Silva, Patrícia Lapa, and Joaquim Tiago
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Congenital cutaneous candidiasis. Exanthema. Term newborn. ,Dermatology ,RL1-803 ,Infectious and parasitic diseases ,RC109-216 - Abstract
Congenital cutaneous candidiasis (CCC) is a rare condition in neonates, mainly in term neonates, that develops in the 1st week of life. Its broad clinical spectrum makes it challenging to differentiate it from other exanthemas in the newborn. The involvement of palms and soles and the presence of pustules are important clinical clues for the differential diagnosis, with cultural examination confirming the diagnosis by identification of Candida spp. Treatment of clinically stable term neonates without evidence of invasive disease is currently controversial. We report a case of CCC in a term newborn with no evidence of invasive disease that evolved into a clinical cure after systemic and topical antifungal treatment.
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- 2023
157. Possible effects of different types of agricultural wastes on food security and mushroom (Pleurotus ostreatus) production
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R. N. De La Cruz-Marcos, F. O. Areche, S. O. P. Segura, J. M. M. López, G. De La Cruz-Calderón, M. A. Q. Solano, A. S. Onofre, B. F. Camayo-Lapa, J. M. M. Otivo, D. D. C. Flores, M. E. E. Pairazaman, J. A. J. Domínguez, S. V. Aguilar, L. Á. F. Aguirre, and D. C. Paricanaza-Ticona
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edible fungus ,nutrients ,proteins ,organic residue ,Pleurotus ostreatus ,Science ,Biology (General) ,QH301-705.5 ,Zoology ,QL1-991 ,Botany ,QK1-989 - Abstract
Abstract One of the new waters, and environmentally friendly agriculture initiatives in Peru is to encourage the utilization of agricultural waste, because low agricultural output is a threat to food security there. The purpose of this research was to evaluate the effect of harvest residues on the basidiocarp production of the fungus Pleurotus Ostreatus, in Acobamba-Huancavelica. The trial had a completely randomized design, and the treatments included T1, barley stubbles; T2, wheat stubbles; T3, pea stubbles; T4, broad bean stubbles; and T5, quinoa stubbles. The research was quantitative in nature, taking the form of an experiment with an applied, explanatory level of design. The recorded data was tabulated and analyzed with analysis of variance, as well as Tukey's test (α:0.05), for which the statistical software Infostat was used. The results are presented in tables and graphs for a better interpretation. As main results, it was obtained that the time (colonization), diameter (stem, pileus), length (stem) and weight (basidiocarps), present statistical differences between treatments showing significant enhancement in all parameters. Despite a numerical difference, a Tukey average comparison test revealed that there was no statistically significant difference between the averages for the variable time for fungus colonisation, suggesting that the treatment T5 in which quinoa substrate showed the greatest average. Treatment T4 in which broad bean stubbles were used gave the most low-average. In conclusion, increment in all parámeters were noted in all treatment of Pleurotus basidiocarps ostreatus under Acobamba conditions.
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- 2023
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158. Saúde mental dos jovens
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Maria Lapa Esteves
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psicologia clínica ,saúde mental ,jovens ,educação ,consciência ,Psychology ,BF1-990 - Abstract
Saúde mental dos jovens, é o tema que vos trago. É um dos temas quentes que temos em mãos. Quando pensamos no futuro, e neste presente pós-pandemia, necessáriamente deparamo-nos a analisar a sociedade de hoje; em particular, os jovens que temos hoje e que serão os adultos, conscientes e agentes de mudanças positivas ou não… Assim, inevitavelmente, se queremos uma sociedade saudável, temos de pensar na saúde mental dos nossos jovens. Temos então, o mote para infinitas discussões, plenários, reflexões seja na escola ou seja o nível parlamentar; e cabe a nós também investigar... é o propósito desta reflexão e futura investigação em alunos universitários. Torna-se urgente ouvir os jovens; é urgente conseguir decifrar o que pensam os jovens nos dias de hoje, numa base ainda mais primária, é muito urgente prescrutar o que sentem on nossos jovens no presente e perante o mal-estar ou uma saúde mental afectada; podermos atuar, dentro das nossas áreas psicologia clinica, psicanálise e educação, entre outras; sempre da melhor forma, a mais assertiva e positiva possivel!
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- 2023
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159. Rift Valley Fever Virus: An Overview of the Current Status of Diagnostics
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Daniele Lapa, Silvia Pauciullo, Ida Ricci, Anna Rosa Garbuglia, Fabrizio Maggi, Maria Teresa Scicluna, and Silvia Tofani
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Rift Valley fever virus ,molecular diagnostics ,serology ,early diagnosis ,Biology (General) ,QH301-705.5 - Abstract
Rift Valley fever is a vector-borne zoonotic disease caused by the Rift Valley fever virus (Phlebovirus genus) listed among the eight pathogens included in the Bluepoint list by the WHO. The transmission is mainly vehicled by Aedes and Culex mosquito species. Symptoms of the disease are varied and non-specific, making clinical diagnosis often challenging, especially in the early stages. Due to the difficulty in distinguishing Rift Valley fever from other viral hemorrhagic fevers, as well as many other diseases that cause fever, an early diagnosis of the infection is important to limit its spread and to provide appropriate care to patients. To date, there is no validated point-of-care diagnostic tool. The virus can only be detected in the blood for a brief period, suggesting that molecular methods alone are not sufficient for case determination. For this, it is preferable to combine both molecular and serological tests. The wide distribution of competent vectors in non-endemic areas, together with global climate change, elicit the spread of RVFV to continents other than Africa, making surveillance activities vital to prevent or to limit the impact of human outbreaks and for a rapid identification of positive cases, making diagnosis a key factor for this achievement.
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- 2024
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160. microRNA–mRNA Networks Linked to Inflammation and Immune System Regulation in Inflammatory Bowel Disease
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Carina de F. de Síbia, Ana E. V. Quaglio, Ellen C. S. de Oliveira, Jéssica N. Pereira, Jovita R. Ariede, Rainer M. L. Lapa, Fábio E. Severino, Patricia P. Reis, Lígia Y. Sassaki, and Rogerio Saad-Hossne
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inflammatory bowel disease ,Crohn’s disease ,ulcerative colitis ,microRNA ,meta-analysis ,Biology (General) ,QH301-705.5 - Abstract
The molecular processes linked to the development and progression of Crohn’s disease (CD) and ulcerative colitis (UC) are not completely understood. MicroRNAs (miRNAs) regulate gene expression and are indicated as diagnostic, prognostic, and predictive biomarkers in chronic degenerative diseases. Our objectives included the identification of global miRNA expression in CD and UC, as well as miRNA target genes, miRNA–mRNA interaction networks, and biological functions associated with these different forms of inflammatory bowel disease (IBD). Methods: By performing a comprehensive meta-analysis, we integrated miRNA expression data from nine studies in IBD. We obtained detailed information on significantly deregulated miRNAs (fold change, FC ≥ 2 and p < 0.05), sample type and number, and platform applied for analysis in the training and validation sets. Further bioinformatic analyses were performed to identify miRNA target genes, by using the microRNA Data Integration Portal tool. We also sought to identify statistically enriched pathways of genes regulated by miRNAs using ToppGene Suite. Additional analyses were performed to filter for genes expressed in intestinal tissue using the European Bioinformatics Institute (EBI) database. Results: Our findings showed the upregulation of 15 miRNAs in CD and 33 in UC. Conversely, six miRNAs were downregulated in CD, while seven were downregulated in UC. These results indicate a greater deregulation of miRNAs in UC compared to CD. Of note, miRNA target genes were enriched for immune system regulation pathways. Among significantly deregulated miRNAs with a higher number of miRNA–target gene interactions, we identified miR-199a-5p and miR-362-3p altered in CD, while among UC case patients, miRNA–target gene interactions were higher for miR-155-5p. Conclusions: The identified miRNAs play roles in regulating genes associated with immune system regulation and inflammation in IBD. Such miRNAs and their target genes have the potential to serve as clinically relevant biomarkers. These findings hold promise for enhancing the accuracy of diagnoses and facilitating the development of personalized treatment strategies for individuals with various forms of IBD.
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- 2024
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161. Assessing the Impact of a Shallow Geothermal System Operation through Multi-Layer Temperature Monitoring in a Mediterranean Climate
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Kamar Aljundi, Ana Vieira, José Lapa, António Figueiredo, and Rafaela Cardoso
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ground temperature distribution ,geothermal energy ,renewable sources ,in-depth temperature acquisition ,Mediterranean climate ,Geology ,QE1-996.5 - Abstract
Shallow Geothermal Energy (SGE) exchanges heat with the ground. In continuous, long-term operation, the initial temperature field can be disturbed, and subsurface thermal changes can be developed. In this paper, the thermal impact of a SGE system under a Mediterranean climate is handled. Temperature monitoring was conducted on 15 investigation boreholes equipped with a total of 92 thermal sensors placed at specific depths. Investigation boreholes were drilled 1–2 m from SGE system borehole heat exchangers installed in a university building. The analysis handles a one-year monitoring period of SGE system operation. Temperature depth profiles, reaching up to 140 m depth, were registered with a 10 min time step, resulting in a large amount of data. Ground thermal conductivity was estimated experimentally and semi-empirically, allowing us to obtain, using a numerical model, the initial undisturbed ground temperature profiles and compare them with the monitored values. Climate data were recorded by the university meteorological station. Globally, the measured and computed data were coherent, and a non-negligible impact of the SGE system operation in the first year was observed. The building orientation as well as the nearby departments had significant impacts on the shallow ground temperature. Maximum ground temperature changes observed at depths higher than 10–20 m, ranging from 2 to 3 °C as observed in different boreholes, indicate that the system is operating efficiently.
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- 2024
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162. Molecular matched targeted therapies for primary brain tumors—a single center retrospective analysis
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Luger, Anna-Luisa, König, Sven, Samp, Patrick Felix, Urban, Hans, Divé, Iris, Burger, Michael C., Voss, Martin, Franz, Kea, Fokas, Emmanouil, Filipski, Katharina, Demes, Melanie-Christin, Stenzinger, Albrecht, Sahm, Felix, Reuss, David E., Harter, Patrick N., Wagner, Sebastian, Hattingen, Elke, Wichert, Jennifer, Lapa, Constantin, Fröhling, Stefan, Steinbach, Joachim P., and Ronellenfitsch, Michael W.
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- 2022
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163. Diverse PSMA expression in primary prostate cancer: reason for negative [68Ga]Ga-PSMA PET/CT scans? Immunohistochemical validation in 40 surgical specimens
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Cytawa, Wojciech, Kircher, Stefan, Kübler, Hubert, Werner, Rudolf A., Weber, Simon, Hartrampf, Philipp, Bandurski, Tomasz, Lass, Piotr, Połom, Wojciech, Matuszewski, Marcin, Wester, Hans-Jürgen, Lapa, Constantin, Rosenwald, Andreas, Seitz, Anna Katharina, and Buck, Andreas K.
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- 2022
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164. Cr(III) dynamic removal in a fixed-bed column by using a co-gasification char
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Dias, D., Bernardo, M., Pinto, F., Fonseca, I., and Lapa, N.
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- 2022
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165. Biochip with Agarose Microcells Containing Thermally Separable Primers
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Zolotov, A. M., Miftakhov, R. A., Ikonnikova, A. Y., Lapa, S. A., Kuznetsova, V. E., Vasiliskov, V. A., Shershov, V. E., Zasedatelev, A. S., Nasedkina, T. V., and Chudinov, A. V.
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- 2022
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166. Impact of Tumor Burden on Normal Organ Distribution in Patients Imaged with CXCR4-Targeted [68Ga]Ga-PentixaFor PET/CT
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Serfling, Sebastian E., Lapa, Constantin, Dreher, Niklas, Hartrampf, Philipp E., Rowe, Steven P., Higuchi, Takahiro, Schirbel, Andreas, Weich, Alexander, Hahner, Stefanie, Fassnacht, Martin, Buck, Andreas K., and Werner, Rudolf A.
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- 2022
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167. Training on Reporting and Data System (RADS) for Somatostatin-Receptor Targeted Molecular Imaging Can Reduce the Test Anxiety of Inexperienced Readers
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Weich, Alexander, Higuchi, Takahiro, Bundschuh, Ralph A., Lapa, Constantin, Serfling, Sebastian E., Rowe, Steven P., Pomper, Martin G., Herrmann, Ken, Buck, Andreas K., Derlin, Thorsten, and Werner, Rudolf A.
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- 2022
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168. Semi-classical wave packet dynamics in non-uniform electric fields
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Lapa, Matthew F. and Hughes, Taylor L.
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Condensed Matter - Mesoscale and Nanoscale Physics - Abstract
We study the semi-classical theory of wave packet dynamics in crystalline solids extended to include the effects of a non-uniform electric field. In particular, we derive a correction to the semi-classical equations of motion (EOMs) for the dynamics of the wave packet center that depends on the gradient of the electric field and on the quantum metric (also called the Fubini-Study, Bures, or Bloch metric) on the Brillouin zone. We show that the physical origin of this term is a contribution to the total energy of the wave packet that depends on its electric quadrupole moment and on the electric field gradient. We also derive an equation relating the electric quadrupole moment of a sharply peaked wave packet to the quantum metric evaluated at the wave packet center in reciprocal space. Finally, we explore the physical consequences of this correction to the semi-classical EOMs. We show that in a metal with broken time-reversal and inversion symmetry, an electric field gradient can generate a longitudinal current which is linear in the electric field gradient, and which depends on the quantum metric at the Fermi surface. We then give two examples of concrete lattice models in which this effect occurs. Our results show that non-uniform electric fields can be used to probe the quantum geometry of the electronic bands in metals and open the door to further studies of the effects of non-uniform electric fields in solids., Comment: v2: 5+4 pages, 2 figures, to appear as a Rapid Communication in PRB
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- 2018
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169. Geometric quench in the fractional quantum Hall effect: exact solution in quantum Hall matrix models and comparison with bimetric theory
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Lapa, Matthew F., Gromov, Andrey, and Hughes, Taylor L.
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Condensed Matter - Strongly Correlated Electrons ,High Energy Physics - Theory - Abstract
We investigate the recently introduced geometric quench protocol for fractional quantum Hall (FQH) states within the framework of exactly solvable quantum Hall matrix models. In the geometric quench protocol a FQH state is subjected to a sudden change in the ambient geometry, which introduces anisotropy into the system. We formulate this quench in the matrix models and then we solve exactly for the post-quench dynamics of the system and the quantum fidelity (Loschmidt echo) of the post-quench state. Next, we explain how to define a spin-2 collective variable $\hat{g}_{ab}(t)$ in the matrix models, and we show that for a weak quench (small anisotropy) the dynamics of $\hat{g}_{ab}(t)$ agrees with the dynamics of the intrinsic metric governed by the recently discussed bimetric theory of FQH states. We also find a modification of the bimetric theory such that the predictions of the modified bimetric theory agree with those of the matrix model for arbitrarily strong quenches. Finally, we introduce a class of higher-spin collective variables for the matrix model, which are related to generators of the $W_{\infty}$ algebra, and we show that the geometric quench induces nontrivial dynamics for these variables., Comment: 18 pages, 1 figure, v2: minor changes, accepted for publication in PRB
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- 2018
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170. Hall Viscosity in the Non-Abelian Quantum Hall Matrix Model
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Lapa, Matthew F., Turner, Carl, Hughes, Taylor L., and Tong, David
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Condensed Matter - Strongly Correlated Electrons ,High Energy Physics - Theory - Abstract
Quantum Hall matrix models are simple, solvable quantum mechanical systems which capture the physics of certain fractional quantum Hall states. Recently, it was shown that the Hall viscosity can be extracted from the matrix model for Laughlin states. Here we extend this calculation to the matrix models for a class of non-Abelian quantum Hall states. These states, which were previously introduced by Blok and Wen, arise from the conformal blocks of Wess-Zumino-Witten conformal field theory models. We show that the Hall viscosity computed from the matrix model coincides with a result of Read, in which the Hall viscosity is determined in terms of the weights of primary operators of an associated conformal field theory., Comment: v2: 9 pages, references added, to appear in PRB
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- 2018
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171. Hall viscosity and geometric response in the Chern-Simons matrix model of the Laughlin states
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Lapa, Matthew F. and Hughes, Taylor L.
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Condensed Matter - Strongly Correlated Electrons ,High Energy Physics - Theory - Abstract
We study geometric aspects of the Laughlin fractional quantum Hall (FQH) states using a description of these states in terms of a matrix quantum mechanics model known as the Chern-Simons matrix model (CSMM). This model was proposed by Polychronakos as a regularization of the noncommutative Chern-Simons theory description of the Laughlin states proposed earlier by Susskind. Both models can be understood as describing the electrons in a FQH state as forming a noncommutative fluid, i.e., a fluid occupying a noncommutative space. Here we revisit the CSMM in light of recent work on geometric response in the FQH effect, with the goal of determining whether the CSMM captures this aspect of the physics of the Laughlin states. For this model we compute the Hall viscosity, Hall conductance in a non-uniform electric field, and the Hall viscosity in the presence of anisotropy (or intrinsic geometry). Our calculations show that the CSMM captures the guiding center contribution to the known values of these quantities in the Laughlin states, but lacks the Landau orbit contribution. The interesting correlations in a Laughlin state are contained entirely in the guiding center part of the state/wave function, and so we conclude that the CSMM accurately describes the most important aspects of the physics of the Laughlin FQH states, including the Hall viscosity and other geometric properties of these states which are of current interest., Comment: v2: 27 pages, 1 figure, minor typos corrected. To appear in PRB
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- 2018
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172. Granulomatous dermatitis: a rare pitfall in lymphoma staging with [18F]FDG-PET/CT
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Enke, Johanna S., Gäble, Alexander, Reitsam, Nic G., Schaller, Tina, Trepel, Martin, Hirschbühl, Klaus, Welzel, Julia, Dierks, Alexander, Kircher, Malte, and Lapa, Constantin
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- 2023
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173. Sarcoidosis mimicking nodal manifestations of marginal zone lymphoma
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Enke, Johanna S., Reitsam, Nic G., Schaller, Tina, Claus, Rainer, Lapa, Constantin, and Dierks, Alexander
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- 2023
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174. Geometric quench in the fractional quantum Hall effect: Exact solution in quantum Hall matrix models and comparison with bimetric theory
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Lapa, MF, Gromov, A, and Hughes, TL
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cond-mat.str-el ,hep-th - Abstract
We investigate the recently introduced geometric quench protocol for fractional quantum Hall (FQH) states within the framework of exactly solvable quantum Hall matrix models. In the geometric quench protocol, a FQH state is subjected to a sudden change in the ambient geometry, which introduces anisotropy into the system. We formulate this quench in the matrix models and then we solve exactly for the postquench dynamics of the system and the quantum fidelity (Loschmidt echo) of the postquench state. Next, we explain how to define a spin-2 collective variable ĝab(t) in the matrix models, and we show that for a weak quench (small anisotropy), the dynamics of ĝab(t) agrees with the dynamics of the intrinsic metric governed by the recently discussed bimetric theory of FQH states. We also find a modification of the bimetric theory such that the predictions of the modified bimetric theory agree with those of the matrix model for arbitrarily strong quenches. Finally, we introduce a class of higher-spin collective variables for the matrix model, which are related to generators of the W8 algebra, and we show that the geometric quench induces nontrivial dynamics for these variables.
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- 2019
175. The tangential punch biopsy
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Breslavets, Maksym and Lapa, Tatiana
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Dermatologists around the world widely utilize skin biopsies, which can be performed using shave, punch, incisional, or excisional techniques [1]. The punch biopsy allows a dermatologist to obtain a full-thickness skin sample. The post-biopsy wound heals by primary closure or second intention [2]. Some suspicious lesions may be located at the body parts that are difficult to access.
- Published
- 2019
176. Competencias digitales y rendimiento académico en estudiantes de una institución de educación técnica-productiva peruana
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Brandon Vicente Ramirez Romero, Becquer Frauberth Camayo Lapa, Amador Godofredo Vilcatoma Sánchez, and José Javier Valdez Arancibia
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competencias digitales ,cultura ecológica ,educación técnica-productiva ,rendimiento académico ,tecnologías de la información y comunicación ,Political science (General) ,JA1-92 ,Social sciences (General) ,H1-99 - Abstract
Para disminuir contagios por la pandemia de COVID-19, las instituciones educativas peruanas migraron a entornos digitales, evidenciándose que, aun cuando las generaciones actuales son diestras en el uso de tecnología para la socialización, no todos la emplean correctamente en procesos de aprendizaje. El objetivo de este artículo es determinar la relación entre competencias digitales y rendimiento académico en estudiantes de una institución de educación técnica-productiva peruana. Para ello, se contextualizó el cuestionario de Gutiérrez-Castillo et al. (2017), validado por expertos locales, y aplicado de forma virtual a través de la plataforma digital a una muestra representada por 52 estudiantes de la especialidad de “Operación de computadoras” del Centro de educación técnico-productiva “Tarma” por tener la mayor cantidad de estudiantes en el momento de la investigación. Se obtuvo como resultado que el 46% y 44% de los estudiantes presentaron un nivel bueno o superior de competencias digitales y rendimiento académico respectivamente; además, que existe relación estadísticamente significativa positiva entre competencias digitales y rendimiento académico (0.572). Se concluye que las competencias digitales son un factor relacionado con el rendimiento académico en los estudiantes de la especialidad analizada, por lo que, si un estudiante tiene mayores competencias digitales, presentará un mejor rendimiento académico.
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- 2022
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177. Safety and immune response kinetics of GRAd-COV2 vaccine: phase 1 clinical trial results
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Chiara Agrati, Concetta Castilletti, Simone Battella, Eleonora Cimini, Giulia Matusali, Andrea Sommella, Alessandra Sacchi, Francesca Colavita, Alessandra M. Contino, Veronica Bordoni, Silvia Meschi, Giulia Gramigna, Federica Barra, Germana Grassi, Licia Bordi, Daniele Lapa, Stefania Notari, Rita Casetti, Aurora Bettini, Massimo Francalancia, Federica Ciufoli, Alessandra Vergori, Serena Vita, Michela Gentile, Angelo Raggioli, Maria M. Plazzi, Antonella Bacchieri, Emanuele Nicastri, Andrea Antinori, Stefano Milleri, Simone Lanini, Stefano Colloca, Enrico Girardi, Roberto Camerini, Giuseppe Ippolito, Francesco Vaia, Antonella Folgori, and Stefania Capone
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Immunologic diseases. Allergy ,RC581-607 ,Neoplasms. Tumors. Oncology. Including cancer and carcinogens ,RC254-282 - Abstract
Abstract Despite the successful deployment of efficacious vaccines and therapeutics, the development of novel vaccines for SARS-CoV-2 remains a major goal to increase vaccine doses availability and accessibility for lower income setting. We report here on the kinetics of Spike-specific humoral and T-cell response in young and old volunteers over 6 months follow-up after a single intramuscular administration of GRAd-COV2, a gorilla adenoviral vector-based vaccine candidate currently in phase-2 of clinical development. At all three tested vaccine dosages, Spike binding and neutralizing antibodies were induced and substantially maintained up to 3 months, to then contract at 6 months. Potent T-cell responses were readily induced and sustained throughout the study period, with only minor decline. No major differences in immune response to GRAd-COV2 vaccination were observed in the two age cohorts. In light of its favorable safety and immunogenicity, GRAd-COV2 is a valuable candidate for further clinical development and potential addition to the COVID-19 vaccine toolbox to help fighting SARS-CoV-2 pandemic.
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- 2022
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178. Convolutional neural networks for automatic image quality control and EARL compliance of PET images
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Elisabeth Pfaehler, Daniela Euba, Andreas Rinscheid, Otto S. Hoekstra, Josee Zijlstra, Joyce van Sluis, Adrienne H. Brouwers, Constantin Lapa, and Ronald Boellaard
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PET ,Image quality ,Convolutional neural network ,Medical physics. Medical radiology. Nuclear medicine ,R895-920 - Abstract
Abstract Background Machine learning studies require a large number of images often obtained on different PET scanners. When merging these images, the use of harmonized images following EARL-standards is essential. However, when including retrospective images, EARL accreditation might not have been in place. The aim of this study was to develop a convolutional neural network (CNN) that can identify retrospectively if an image is EARL compliant and if it is meeting older or newer EARL-standards. Materials and methods 96 PET images acquired on three PET/CT systems were included in the study. All images were reconstructed with the locally clinically preferred, EARL1, and EARL2 compliant reconstruction protocols. After image pre-processing, one CNN was trained to separate clinical and EARL compliant reconstructions. A second CNN was optimized to identify EARL1 and EARL2 compliant images. The accuracy of both CNNs was assessed using fivefold cross-validation. The CNNs were validated on 24 images acquired on a PET scanner not included in the training data. To assess the impact of image noise on the CNN decision, the 24 images were reconstructed with different scan durations. Results In the cross-validation, the first CNN classified all images correctly. When identifying EARL1 and EARL2 compliant images, the second CNN identified 100% EARL1 compliant and 85% EARL2 compliant images correctly. The accuracy in the independent dataset was comparable to the cross-validation accuracy. The scan duration had almost no impact on the results. Conclusion The two CNNs trained in this study can be used to retrospectively include images in a multi-center setting by, e.g., adding additional smoothing. This method is especially important for machine learning studies where the harmonization of images from different PET systems is essential.
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- 2022
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179. The Use Virtual Reality to Assist In The Preparation Of An Ergonomic Analysis Of Nuclear Facilities
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Daniel Mol Machado, Antonio Carlos de Abreu Mól, Andre Cotelli do Espírito Santo, Mario Cesar Vidal, and Celso Marcelo Franklin Lapa
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Ergonomic Analysis ,Virtual Reality ,Physical security ,Science - Abstract
Ergonomic Analysis consists of making value judgments about the global performance of certain man-machine or man-task systems and may result from a demand related to conditions and/or safety at work. However, during the performance of the Ergonomic Analysis, the presence of ergonomists can interfere with the work progress, which limits the observation time. Organizations that have risk areas have already been using simulated exercises to train their professionals. With the use of simulation tools, it becomes increasingly necessary to develop methods and techniques that allow the performance of this training, as close as possible to real work activities. In this context, this article proposed to create and verify if the use of Virtual Reality can help the Ergonomic Analysis of Work, developing scenarios and virtual simulation environments, contextualized by the Ergonomics perspective. For this purpose, a case study was carried out at the Institute of Nuclear Engineering where the Ergonomic Work Analysis and the modeling of the virtual environment were carried out. Finally, from the results presented, it can be concluded that Virtual Reality serves as a complementary tool to assist the ergonomist in the Ergonomic Analysis process, allowing him to use the tool to reduce risks, saving time and improving his performance.
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- 2023
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180. Disfluências e Gaguez: Revisão e Critérios de Referenciação
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José Alarcão, Isabel Lucas, Lígia Lapa, Joana Monteiro, and Teresa Mota Castelo
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Criança ,Gaguez ,Perturbações da Fluência com Início na Infância ,Perturbação fala ,Medicine ,Medicine (General) ,R5-920 - Abstract
A gaguez é uma perturbação da comunicação a nível da fluência em que a pessoa sabe claramente a mensagem que quer transmitir, mas o seu discurso é caracterizado por alterações do ritmo, repetições, prolongamentos, pausas e bloqueios, podendo ainda associar-se a quadros de ansiedade ou tensão emocional. Até uma em cada seis crianças, tipicamente entre os dois e os cinco anos, experienciam um período de disfluência transitória, com habitual recuperação espontânea até à idade escolar, verificando-se uma prevalência de gaguez em até 1% da população adulta, com maior incidência no sexo masculino (4:1). Em Portugal, é estimado que a gaguez afete cerca de 100 mil pessoas, adquirindo particular importância pela sua frequência e associação a redução da autoestima, ansiedade e isolamento social com impacto na capacidade de comunicação do indivíduo e no seu bem-estar e interações sociais. Este artigo tem como objectivo alertar para a complexidade da abordagem diagnóstica e terapêutica em idade pediátrica, com particular incidência na diferenciação entre disfluências normais da fala e perturbação da fluência com início na infância (gaguez) e critérios de referenciação, pretendendo consciencializar e facilitar a deteção e orientação precoce destes casos.
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- 2023
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181. Opportunities and challenges in the anaerobic co-digestion of municipal sewage sludge and fruit and vegetable wastes: A review
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André Azevedo, Nuno Lapa, Margarida Moldão, and Elizabeth Duarte
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Anaerobic co-digestion ,Bioenergy recovery ,Biogas yield ,Fruit and vegetable wastes ,Operational conditions ,Municipal sewage sludge ,Renewable energy sources ,TJ807-830 ,Agriculture (General) ,S1-972 - Abstract
To overcome the anthropogenic impacts resulting from the constant growth of the world population, industries like wastewater treatment plants and food processing must be adapted to follow this tendency and suppress the associated challenges and needs arising from this global situation. In the context of the circular economy, optimising the biogas produced in the anaerobic digesters during sludge stabilisation is fundamental to ensure the energy self-sufficiency of wastewater treatment plants. The anaerobic co-digestion of two or more substrates is a viable option to overcome the drawbacks of mono-digestion and to improve methane production. Considering the economic viability of the anaerobic digestion system, it is of major importance to address the potential of the spare capacity existing in the anaerobic reactors by incorporating readily biodegradable wastes.This review compiles the works published between 2015 and 2023 regarding the anaerobic co-digestion of municipal sewage sludge with fruit and vegetable wastes, presenting a critical analysis of the gaps and future perspectives on this topic. The results demonstrated the effectiveness of co-digestion to correct imbalances from mono-digestion, and in some works, mono-digestion of fruit and vegetable wastes obtained higher biogas yields than the mono-digestion of municipal sewage sludge. For instance, the increment in biogas production varied from around 4 up to 500% when comparing mono-digestion with co-digestion trials. In two studies, the biogas production from fruit and vegetable wastes was 13 and 94% higher than in the trials with only municipal sewage sludge. Multi-stage systems enhanced anaerobic digestion due to the improvement in the early stages of the process, namely the hydrolysis which is usually the limiting phase. A significant number of the experimental trials (9 out of 20 studies) were performed in batch reactors due to easy operation and maintenance, revealing the gap of studies with other types of reactors like the continuous stirred tank reactor, which is the most used in wastewater treatment plants. The reduced number of articles within this scope (20) demonstrates that there is still potential to improve the knowledge and fill in the existing gaps, aiming to increase the energetic self-sufficiency of wastewater treatment plants.
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- 2023
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182. Prenatal repair of gastroschisis using partial carbon dioxide insufflation fetoscopy: lessons learned
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Gustavo Henrique de Oliveira, Gregório Lorenzo Acácio, Rodrigo Tadeu Russo Gonçalves, Javier Svetliza, Gustavo Yano Callado, Cristiane de Moraes Dias, Denise Cristina Mós Vaz-Oliani, Ramen H. Chmait, and Denise Araújo Lapa
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Gastroschisis ,Abdominal wall ,Fetoscopy ,Fetal therapies ,Fetus ,Infant, newborn ,Carbon dioxide ,Insufflation ,Fetal distress ,Medicine - Abstract
ABSTRACT We report the long-term outcomes of a case of prenatal gastroschisis repair using a fully percutaneous fetoscopic approach with partial carbon dioxide insufflation. Surgery was performed as an experimental procedure before the scheduled elective birth. The fetal intestines were successfully returned to the abdominal cavity without any fetal or maternal complications. Ultrasonography performed 24 hours later revealed bowel peristalsis and no signs of fetal distress. After 48 hours, partial extrusion of the small bowel was observed, and the fetus was delivered. Gastroschisis repair was immediately performed upon delivery using the EXIT-like procedure as per our institutional protocol. The newborn did not require assisted mechanical ventilation, was discharged at 14 days of age and was then exclusively breastfed. At 3-year follow-up, the patient had no associated gastroschisis-related complications. This is the first case of prenatal repair of gastroschisis, which provides baseline knowledge for future researchers on the potential hurdles and management of prenatal repair.
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- 2023
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183. Photosynthetic modification of plants through recent technologies: a valuable way to ensure crop fortification
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F. O. Areche, J. M. M. López, C. M. C. Mamani, M. N. M. Alberto, V. G. S. Araujo, P. A. P. Pastrana, B. F. Camayo-Lapa, M. A. Quispe-Solano, J. Y. Saldarriaga, C. P. E. Ayre, S. M. Carrasco, A. V. Roman, D. D. C. Flores, and D. D. Cruz Nieto
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photosynthetic processes ,fortification ,technologies ,crop yield ,Science ,Biology (General) ,QH301-705.5 ,Zoology ,QL1-991 ,Botany ,QK1-989 - Abstract
Abstract The 2030 Sustainable Development Goals of the United Nations include a strong emphasis on ending hunger worldwide. According to the 2019 Global Food Security Index, while 88% of countries claim there is sufficient food supply in their country, the sad reality is that 1 in 3 countries is facing insufficient availability of food supply, which means that in those countries, more than 10% of the population is malnourished. Since nutrition is crucial to leading a healthy life and satisfying food security needs, several governments have turned to national nutrition surveys to gauge the extent of malnutrition in their populations. Plants are able to grow, develop, and store nutrients by photosynthesis, which convert light into chemical energy through cell redox regulatory networks. A photosynthesis system's electron flow may be adjusted to accommodate varying light and environmental circumstances. Many techniques exist for controlling the flow of electrons emitted during light processes in order to save or waste energy. The two protein molecules TROL and flavoenzyme ferredoxin (oxidoreductase+NADP) (FNR) interact dynamically to form an excellent molecular switch capable of splitting electrons from the photosystem. The TROL-FNR bifurcation may be limited by either generating NADPH or preventing reactive oxygen species from propagating. TROL-based genome editing is an experimental method for enhancing plant stress and defensive responses, efficiency, and ultimately agricultural production.
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- 2023
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184. Ablação da Fibrilação Atrial: Impacto da Ecocardiografia Intracardíaca na Redução do Tempo de Procedimento e Internação
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Roberto Tofani Sant`Anna, Gustavo Glotz de Lima, Marco Aurélio Lumertz Saffi, Marcelo Lapa Kruse, and Tiago Luiz Luz Leiria
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Fibrilação Atrial/complicações ,Ablação por Cateter ,Ecocardiografia/métodos ,Hospitalização ,Veias Pulmonares/diagnóstico por imagem ,Diseases of the circulatory (Cardiovascular) system ,RC666-701 - Abstract
Resumo Fundamento O ecocardiograma intracardíaco (EIC) permite visualizar estruturas cardíacas e reconhecer complicações durante a ablação da fibrilação atrial (AFA). Comparado ao ecocardiograma transesofágico (ETE), o EIC é menos sensível para detecção de trombo no apêndice atrial, porém requer mínima sedação e menos operadores, tornando-o atrativo num cenário de recursos restritos. Objetivo Comparar 13 casos de AFA utilizando EIC (grupo AFA-EIC) com 36 casos de AFA utilizando ETE (grupo AFA-ETE). Método Trata-se de corte prospectiva realizada em um único centro. O desfecho principal foi o tempo de procedimento. Desfechos secundários tempo de fluoroscopia, dose de radiação (mGy/cm2), complicações maiores e tempo de internação hospitalar em horas. O perfil clínico foi comparado pelo escore CHA2DS2-VASc. Um valor de p
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- 2023
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185. Parent Involvement Factors during High School from the Perspectives of Academically Successful Black Male College Students: Implications for School Counselors
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Smith, Vernon L. S., Smith, Sharlene M., Bethell, Detra S., and Lapa, Amanda
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This study used a strengths-based approach to examine the distribution of perceived parent involvement factors during high school from the perspective of academically successful Black male college students. Black males enrolled in an undergraduate degree program at a university in the southern region of the United States completed Yan and Lin's "Parent Involvement During High School" survey, adapted from the National Education Longitudinal Study of 1988. Results revealed that among the distribution of the three factors (family obligation, parent information network, and family norms), Family norms was perceived as the most prevalent parent involvement subscale factor during high school for this particular population. The family norms factor subscale's parent--teenager relationship emerged as the most dominant variable followed by educational expectations. We delineate implications for school counselors and research.
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- 2021
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186. New Method for Evaluating the Substrate Efficiency of Modified Deoxynucleoside Triphosphates for Selex
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Lapa, S. A., Antipova, O. S., and Chudinov, A. V.
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- 2022
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187. Melatonin Administration Prevents Placental and Fetal Changes Induced by Gestational Diabetes
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de Melo, Ismaela Maria Ferreira, Ferreira, Cintia Giselle Martins, Alves, Érique Ricardo, D’Assunção, Carolline Guimarães, Neto, Clovis José Cavalcanti Lapa, de Albuquerque, Yuri Mateus Lima, Wanderley Teixeira, Valéria, and Teixeira, Álvaro Aguiar Coelho
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- 2022
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188. The effect of illumination on p-n junction diodes based on Yb-doped CuO thin films produced by ultrasonic spray pyrolysis method
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Lapa, Havva Elif
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- 2023
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189. Alttaş Sıcaklığına Bağlı Olarak Ultrasonik Sprey Piroliz Yöntemi ile Üretilen CuO İnce Filmlerin İncelenmesi
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Havva Elif Lapa
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ultrasonik sprey piroliz ,cuo ince film ,enerji malzemeleri ,elektronik malzemeler ,ultrasonic spray pyrolysis ,cuo thin film ,energy materials ,electronic materials ,Science (General) ,Q1-390 - Abstract
Bu çalışmada, CuO ince filmler, ultrasonik sprey piroliz (USP) yöntemi ile farklı alttaş sıcaklıklarında (350, 400, 450 ve 500 ºC) cam altlıklar üzerine biriktirilmiştir ve ardından 525 ºC’de tavlanmıştır. X-ışını kırınımı (XRD) analizlerinde, 350 ºC alttaş sıcaklığında ve tavlanmayan durumda ince filmlerde pik şiddetine rastlanmamıştır. Diğer filmlerin XRD desenlerinde ~36º ve ~39º’de iki belirgin pik gözlemlenmiştir. Bu pikler CuO’in monoklinik kristal yapısına ait karakteristik piklerdir. Atomik kuvvet mikroskobu (AFM) ve taramalı elektron mikroskobu (SEM) görüntülerinden, CuO ince filmlerin yüzeylerinin pürüzsüz olmadığı ve tavlama ile tane yığınlarının meydana geldiği gözlenmiştir. CuO ince filmlerin optik özellikleri ultraviyole- görünür bölge (UV-Vis) ölçümleri ile analiz edilmiştir. Tauc grafiklerinden yasak band aralığı değerleri (Eg), tavlanmamış ve tavlanan numuneler için hesaplanmıştır. USP yöntemiyle üretilen CuO ince filmlerin yapısal, morfolojik ve optik özelliklerinin alttaş sıcaklığı ile kontrol edilebileceği görülmüştür.
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- 2022
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190. Persistent Spike-specific T cell immunity despite antibody reduction after 3 months from SARS-CoV-2 BNT162b2-mRNA vaccine
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Chiara Agrati, Concetta Castilletti, Delia Goletti, Alessandra Sacchi, Veronica Bordoni, Davide Mariotti, Stefania Notari, Giulia Matusali, Silvia Meschi, Linda Petrone, Alessandra Aiello, Saeid Najafi Fard, Chiara Farroni, Francesca Colavita, Daniele Lapa, Sara Leone, Alessandro Agresta, Maria Capobianchi, Giuseppe Ippolito, Francesco Vaia, Vincenzo Puro, and INMI COVID-19 Vaccine Study Group
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Medicine ,Science - Abstract
Abstract Vaccine is the main public health measure to reduce SARS-CoV-2 transmission and hospitalization, and a massive scientific effort worldwide resulted in the rapid development of effective vaccines. This work aimed to define the dynamics and persistence of humoral and cell-mediated immune response in Health Care Workers who received a two-dose BNT162b2-mRNA vaccination. Serological response was evaluated by quantifying anti-RBD and neutralizing antibodies while cell-mediated response was performed by a whole blood test quantifying Th1 cytokines (IFN-γ, TNF-α, IL-2) produced in response to Spike peptides. BNT162b2-mRNA vaccine induced both humoral and cell-mediated immune response against Spike in all HCW early after the second dose. After 12 weeks from vaccination, the titer of anti-RBD antibodies as well as their neutralization function decreased while the Spike-specific T-cells persisted at the same level as soon after vaccine boost. Of note, a correlation between cellular and humoral response persevered, suggesting the persistence of a coordinated immune response. The long lasting cell-mediated immune response after 3 months from vaccination highlight its importance in the maintaining of specific immunity able to expand again to fight eventual new antigen encountering.
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- 2022
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191. Arctic Curves in path models from the Tangent Method
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Di Francesco, Philippe and Lapa, Matthew F.
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Mathematical Physics ,Condensed Matter - Statistical Mechanics ,Mathematics - Combinatorics - Abstract
Recently, Colomo and Sportiello introduced a powerful method, known as the \emph{Tangent Method}, for computing the arctic curve in statistical models which have a (non- or weakly-) intersecting lattice path formulation. We apply the Tangent Method to compute arctic curves in various models: the domino tiling of the Aztec diamond for which we recover the celebrated arctic circle; a model of Dyck paths equivalent to the rhombus tiling of a half-hexagon for which we find an arctic half-ellipse; another rhombus tiling model with an arctic parabola; the vertically symmetric alternating sign matrices, where we find the same arctic curve as for unconstrained alternating sign matrices. The latter case involves lattice paths that are non-intersecting but that are allowed to have osculating contact points, for which the Tangent Method was argued to still apply. For each problem we estimate the large size asymptotics of a certain one-point function using LU decomposition of the corresponding Gessel-Viennot matrices, and a reformulation of the result amenable to asymptotic analysis., Comment: 63 pages, 13 figures
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- 2017
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192. Perturbative and global anomalies in bosonic analogues of integer quantum Hall and topological insulator phases
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Lapa, Matthew F. and Hughes, Taylor L.
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Condensed Matter - Strongly Correlated Electrons ,High Energy Physics - Theory - Abstract
We study perturbative and global anomalies at the boundaries of bosonic analogues of integer quantum Hall (BIQH) and topological insulator (BTI) phases using a description of the boundaries of these phases in terms of a nonlinear sigma model (NLSM) with Wess-Zumino term. One of the main results of the paper is that these anomalies are robust against arbitrary smooth deformations of the target space of the NLSM which describes the phase, provided that the deformations also respect the symmetry of the phase. In the first part of the paper we discuss the perturbative $U(1)$ anomaly at the boundary of BIQH states in all odd (spacetime) dimensions. In the second part we study global anomalies at the boundary of BTI states in even dimensions. In a previous work [Phys. Rev. B 95, 035149 (2017)] we argued that the boundary of the BTI phase exhibits a global anomaly which is an analogue of the parity anomaly of Dirac fermions in three dimensions. Here we elevate this argument to a proof for the boundary of the two-dimensional BTI state by explicitly computing the partition function of the gauged NLSM describing the boundary. We then use the powerful equivariant localization technique to show that this global anomaly is robust against all smooth deformations of the target space of the NLSM which preserve the $U(1)\rtimes\mathbb{Z}_2$ symmetry of the BTI state. We also comment on the difficulties of generalizing this latter proof to higher dimensions. Finally, we discuss the expected low energy behavior of the boundary theories studied in this paper when the coupling constants are allowed to flow under the renormalization group., Comment: 22 pages, three appendices, v2: 24 pages, three appendices, and a new section (Sec. IV). To appear in PRB
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- 2017
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193. Magnetic vortex nucleation/annihilation in artificial-ferrimagnet microdisks
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Lapa, Pavel N., Ding, Junjia, Phatak, Charudatta, Pearson, John E., Jiang, J. S., Hoffmann, Axel, and Novosad, Valentine
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Condensed Matter - Other Condensed Matter ,Condensed Matter - Mesoscale and Nanoscale Physics - Abstract
The topological nature of magnetic-vortex state gives rise to peculiar magnetization reversal observed in magnetic microdisks. Interestingly, magnetostatic and exchange energies which drive this reversal can be effectively controlled in artificial ferrimagnet heterostructures composed of rare-earth and transition metals. 25x[Py(t)/Gd(t)] (t=1 or 2 nm) superlattices demonstrate a pronounced change of the magnetization and exchange stiffness in a 10-300 K temperature range as well as very small magnetic anisotropy. Due to these properties, the magnetization of cylindrical microdisks composed of these artificial ferrimagnets can be transformed from the vortex to uniformly-magnetized states in a permanent magnetic field by changing the temperature. We explored the behavior of magnetization in 1.5-micrometer 25x[Py(t)/Gd(t)] (t=1 or 2 nm) disks at different temperatures and magnetic fields and observed that due to the energy barrier separating vortex and uniformly-magnetized states, the vortex nucleation and annihilation occur at different temperatures. This causes the temperature dependences of the Py/Gd disks magnetization to demonstrate unique hysteretic behavior in a narrow temperature range. It was discovered that for the 25x[Py(2 nm)/Gd(2 nm)] microdisks the vortex can be metastable at a certain temperature range.
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- 2017
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194. Canonical quantization of nonlinear sigma models with theta term, with applications to symmetry-protected topological phases
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Lapa, Matthew F. and Hughes, Taylor L.
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Condensed Matter - Strongly Correlated Electrons ,High Energy Physics - Theory - Abstract
We canonically quantize $O(D+2)$ nonlinear sigma models (NLSMs) with theta term on arbitrary smooth, closed, connected, oriented $D$-dimensional spatial manifolds $\mathcal{M}$, with the goal of proving the suitability of these models for describing symmetry-protected topological (SPT) phases of bosons in $D$ spatial dimensions. We show that in the disordered phase of the NLSM, and when the coefficient $\theta$ of the theta term is an integer multiple of $2\pi$, the theory on $\mathcal{M}$ has a unique ground state and a finite energy gap to all excitations. We also construct the ground state wave functional of the NLSM in this parameter regime, and we show that it is independent of the metric on $\mathcal{M}$ and given by the exponential of a Wess-Zumino term for the NLSM field, in agreement with previous results on flat space. Our results show that the NLSM in the disordered phase and at $\theta=2\pi k$, $k\in\mathbb{Z}$, has a symmetry-preserving ground state but no topological order (i.e., no topology-dependent ground state degeneracy), making it an ideal model for describing SPT phases of bosons. Thus, our work places previous results on SPT phases derived using NLSMs on solid theoretical ground. To canonically quantize the NLSM on $\mathcal{M}$ we use Dirac's method for the quantization of systems with second class constraints, suitably modified to account for the curvature of space. In a series of four appendices we provide the technical background needed to follow the discussion in the main sections of the paper., Comment: 24 pages, 4 appendices, 2 figures
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- 2017
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195. Magnetization reversal in Py/Gd heterostructures
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Lapa, Pavel N., Ding, Junjia, Pearson, John E., Novosad, Valentine, Jiang, J. S., and Hoffmann, Axel
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Condensed Matter - Mesoscale and Nanoscale Physics - Abstract
Using a combination of magnetometry and magnetotransport techniques, we studied temperature and magnetic field behavior of magnetization in Py/Gd heterostructures. It was shown quantitatively that proximity with Py enhances magnetic order of Gd. Micromagnetic simulations demonstrate that a spin-flop transition observed in a Py/Gd bilayer is due to exchange-spring rotation of magnetization in the Gd layer. Transport measurements show that the magnetoresistance of a [Py(2 nm)/Gd(2 nm)]25 multilayer changes sign at the compensation temperature and below 20 K. The positive magnetoresistance above the compensation temperature can be attributed to an in-plane domain-wall, which appears because of the structural inhomogeneity of the film over its thickness. By measuring the angular dependence of resistance we are able to determine the angle between magnetizations in the multilayer and the magnetic field at different temperatures. The measurement reveals that due to a change of the chemical thickness profile, a non-collinear magnetization configuration is only stable in magnetic fields above 10 kOe., Comment: 17 pages, 7 figures
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- 2017
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196. Luminosity-dependent changes of the cyclotron line energy and spectral hardness in Cep X-4
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Vybornov, V., Klochkov, D., Gornostaev, M., Postnov, K., Sokolova-Lapa, E., Staubert, R., Pottschmidt, K., and Santangelo, A.
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Astrophysics - High Energy Astrophysical Phenomena - Abstract
X-ray spectra of accreting pulsars are generally observed to vary with their X-ray luminosity. In particular, the hardness of the X-ray continuum is found to depend on luminosity. In a few sources, the correlation between the energy of the cyclotron resonance scattering feature (CRSF) and the luminosity is clear. Different types (signs) of the correlation are believed to reflect different accretion modes. We analyse two NuSTAR observations of the transient accreting pulsar Cep X-4 during its 2014 outburst. Our analysis is focused on a detailed investigation of the dependence of the CRSF energy and of the spectral hardness on X-ray luminosity, especially on short timescales. To investigate the spectral changes as a function of luminosity within each of the two observations, we used the intrinsic variability of the source on the timescale of individual pulse cycles (tens of seconds), the so-called pulse-to-pulse variability. We find that the NuSTAR spectrum of Cep X-4 contains two CRSFs: the fundamental line at ~30 keV and its harmonic at ~55 keV. We find for the first time that the energy of the fundamental CRSF increases and the continuum becomes harder with increasing X-ray luminosity not only between the two observations, that is, on the long timescale, but also within an individual observation, on the timescale of a few tens of seconds. We investigate these dependencies in detail including their non-linearity. We discuss a possible physical interpretation of the observed behaviour in the frame of a simple one-dimensional model of the polar emitting region with a collisionless shock formed in the infalling plasma near the neutron star surface. With this model, we are able to reproduce the observed variations of the continuum hardness ratio and of the CRSF energy with luminosity., Comment: 11 pages, 9 figures; accepted for publication in A&A
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- 2017
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197. Cyclotron resonant scattering feature simulations. II. Description of the CRSF simulation process
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Schwarm, F. -W., Ballhausen, R., Falkner, S., Schönherr, G., Pottschmidt, K., Wolff, M. T., Becker, P. A., Fürst, F., Marcu-Cheatham, D. M., Hemphill, P. B., Sokolova-Lapa, E., Dauser, T., Klochkov, D., Ferrigno, C., and Wilms, J.
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Astrophysics - High Energy Astrophysical Phenomena - Abstract
Cyclotron resonant scattering features (CRSFs) are formed by scattering of X-ray photons off quantized plasma electrons in the strong magnetic field (of the order 10^12 G) close to the surface of an accreting X-ray pulsar. The line profiles of CRSFs cannot be described by an analytic expression. Numerical methods such as Monte Carlo (MC) simulations of the scattering processes are required in order to predict precise line shapes for a given physical setup, which can be compared to observations to gain information about the underlying physics in these systems. A versatile simulation code is needed for the generation of synthetic cyclotron lines. Sophisticated geometries should be investigatable by making their simulation possible for the first time. The simulation utilizes the mean free path tables described in the first paper of this series for the fast interpolation of propagation lengths. The code is parallelized to make the very time consuming simulations possible on convenient time scales. Furthermore, it can generate responses to mono-energetic photon injections, producing Green's functions, which can be used later to generate spectra for arbitrary continua. We develop a new simulation code to generate synthetic cyclotron lines for complex scenarios, allowing for unprecedented physical interpretation of the observed data. An associated XSPEC model implementation is used to fit synthetic line profiles to NuSTAR data of Cep X-4. The code has been developed with the main goal of overcoming previous geometrical constraints in MC simulations of CRSFs. By applying this code also to more simple, classic geometries used in previous works, we furthermore address issues of code verification and cross-comparison of various models. The XSPEC model and the Green's function tables are available online at http://www.sternwarte.uni-erlangen.de/research/cyclo ., Comment: A&A, in press
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- 2017
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198. Methodology to Assist in Training Maneuvers of Operation of Pumps of a Nuclear Plant Using Virtual Reality.
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Machado, Daniel Mól, dos Santos, Gustavo Souza Pinheiro, do Espirito Santo, Andre Cotelli, de Abreu Mól, Antonio Carlos, Lapa, Celso Marcelo Franklin, and dos Santos Grecco, Claudio Henrique
- Abstract
In power plants, one of the important maneuvers is the switching of pumps, where incorrect execution can even cause the unit to shut down. Therefore, the objective of this paper is to create a virtual environment for training the critical maneuver of the pump switching operation. The method used as reference was the specific procedure for the actual execution of the pump switching maneuver. Then the procedure was interpreted in order to reproduce in the virtual environment the same behaviors as in the real environment. Subsequently, visits to the field, control room, and control room simulator were undertaken in order to obtain material and data for the assembly of the virtual environment. Finally, with all the information collected, a virtual environment was created. The result was the creation of a system and equipment of interest for switching pumps interactively in the virtual environment, with great fidelity to the real environment. Tests were done by nuclear power plant operators and instructors on this virtual environment. The test results of this group demonstrated that the virtual environment created is a good tool to significantly assist in this type of training, as it promotes the experience of imposed challenges, which are common to several other systems of a nuclear power plant. In this way, the choice of a system to be reproduced in a virtual environment that represents the challenge of training critical maneuvers that affect the reactor was fundamental. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
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199. Long Term Assessment of Anti-SARS-CoV-2 Immunogenicity after mRNA Vaccine in Persons Living with HIV
- Author
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Alessandra Vergori, Alessandro Cozzi-Lepri, Giulia Matusali, Stefania Cicalini, Veronica Bordoni, Silvia Meschi, Valentina Mazzotta, Francesca Colavita, Marisa Fusto, Eleonora Cimini, Stefania Notari, Veronica D’Aquila, Simone Lanini, Daniele Lapa, Roberta Gagliardini, Davide Mariotti, Giuseppina Giannico, Enrico Girardi, Francesco Vaia, Chiara Agrati, Fabrizio Maggi, and Andrea Antinori
- Subjects
HIV-1 infection ,SARS-CoV-2 infection ,neutralizing antibodies ,mRNA vaccines ,T cell immunity ,immunity waning ,Medicine - Abstract
(1) Background: Waning of neutralizing and cell-mediated immune response after the primary vaccine cycle (PVC) and the first booster dose (BD) is of concern, especially for PLWH with a CD4 count ≤200 cells/mm3. (2) Methods: Neutralizing antibodies (nAbs) titers by microneutralization assay against WD614G/Omicron BA.1 and IFNγ production by ELISA assay were measured in samples of PLWH at four time points [2 and 4 months post-PVC (T1 and T2), 2 weeks and 5 months after the BD (T3 and T4)]. Participants were stratified by CD4 count after PVC (LCD4, ≤200/mm3; ICD4, 201–500/mm3, and HCD4, >500/mm3). Mixed models were used to compare mean responses over T1–T4 across CD4 groups. (3) Results: 314 PLWH on ART (LCD4 = 56; ICD4 = 120; HCD4 = 138) were enrolled. At T2, levels of nAbs were significantly lower in LCD4 vs. ICD4/HCD4 (p = 0.04). The BD was crucial for increasing nAbs titers above 1:40 at T3 and up to T4 for WD614G. A positive T cell response after PVC was observed in all groups, regardless of CD4 (p = 0.31). (4) Conclusions: Waning of nAbs after PVC was more important in LCD4 group. The BD managed to re-establish higher levels of nAbs against WD614G, which were retained for 5 months, but for shorter time for Omicron BA.1. The T cellular response in the LCD4 group was lower than that seen in participants with higher CD4 count, but, importantly, it remained above detectable levels over the entire study period.
- Published
- 2023
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200. Nipah Virus: An Overview of the Current Status of Diagnostics and Their Role in Preparedness in Endemic Countries
- Author
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Anna Rosa Garbuglia, Daniele Lapa, Silvia Pauciullo, Hervé Raoul, and Delphine Pannetier
- Subjects
Nipah virus ,zoonosis ,One Health ,molecular diagnosis ,infection ,Microbiology ,QR1-502 - Abstract
Nipah virus (NiV) is a paramyxovirus responsible for a high mortality rate zoonosis. As a result, it has been included in the list of Blueprint priority pathogens. Bats are the main reservoirs of the virus, and different clinical courses have been described in humans. The Bangladesh strain (NiV-B) is often associated with severe respiratory disease, whereas the Malaysian strain (NiV-M) is often associated with severe encephalitis. An early diagnosis of NiV infection is crucial to limit the outbreak and to provide appropriate care to the patient. Due to high specificity and sensitivity, qRT-PCR is currently considered to be the optimum method in acute NiV infection assessment. Nasal swabs, cerebrospinal fluid, urine, and blood are used for RT-PCR testing. N gene represents the main target used in molecular assays. Different sensitivities have been observed depending on the platform used: real-time PCR showed a sensitivity of about 103 equivalent copies/reaction, SYBRGREEN technology’s sensitivity was about 20 equivalent copies/reaction, and in multiple pathogen card arrays, the lowest limit of detection (LOD) was estimated to be 54 equivalent copies/reaction. An international standard for NiV is yet to be established, making it difficult to compare the sensitivity of the different methods. Serological assays are for the most part used in seroprevalence studies owing to their lower sensitivity in acute infection. Due to the high epidemic and pandemic potential of this virus, the diagnosis of NiV should be included in a more global One Health approach to improve surveillance and preparedness for the benefit of public health. Some steps need to be conducted in the diagnostic field in order to become more efficient in epidemic management, such as development of point-of-care (PoC) assays for the rapid diagnosis of NiV.
- Published
- 2023
- Full Text
- View/download PDF
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