Sampling rate in the dynamic speckle analysis

Dynamic laser speckle and its biological version (biospeckle laser) have been used in many areas of knowledge. Its noninvasive approach allows the application in advantage regarding those that need contact or damage the analyzed sample. However, one needs the sharp adjust of the image acquiring and processing. In this article, we show how the variation of sampling rate in a dynamic speckle analysis affects the value of dynamic speckle indexes concerning the absolute value of the differences index, the temporal speckle standard deviation index, and the temporal speckle mean index. We show that the dynamic speckle index value changes its maximum excursion with the variation of sampling rate, affected directly by the camera's time integration (time of exposure). We highlight the importance of knowing the frequency band of the analyzed phenomenon and its signal to choose the appropriate sampling rate, with the recommendation of using the lowest sampling rate possible¿without compromise the speckle grains¿to obtain an acceptable maximum excursion and an illumination level with a good signal-noise ratio. The results will help those who work with the phenomenon/technique to enhance their analysis tailoring the set up and yielding reliable results, since the optical method demands a rigorous bias of the image acquiring and processing

Implementation of an Artificial Neural Network on the Test Barcelona Workstation As a Predictive Model for the Classification of Normal, Mild Cognitive Impairment and Alzheimer’s Disease Subjects Using the Neuronorma Battery

Objective: To develop and implement an online Artificial Neural Network (ANN) that provides the probability of a subject having mild cognitive impairment (MCI) or Alzheimer’s disease (AD). Method: Different ANNs were trained using a sample of 350 controls (CONT), 75 MCI and 93 AD subjects. The ANN structure chosen was the following: (1) an input layer of 33 cognitive variables from the Neuronorma battery plus two sociodemographic variables, age and education. This layer was reduced to a 15 features input vector using Multiple Discriminant Analysis method, (2) one hidden layer with 8 neurons, and (3) three output neurons corresponding to the 3 expected cognitive states. This ANN was defined in a previous study [28]. The ANN was implemented on the web site www.test-barcelona.com (Test Barcelona Workstation) [9]. Results: When comparing CONT, MCI and AD participants, the best ANN correctly classifies up to 94,87% of the study participants. Conclusions: The online implemented ANN, delivers the probabilities (%) of belonging to the CONT, MCI and AD groups of a subject assessed using the 35 characteristics (variables) of the Neuronorma profile. This tool is a good complement for the interpretation of cognitive profiles. This technology improves clinical decision making. Keywords: Artificial Neural Network, Probability, Alzheimer disease, Test Barcelona Workstation

Kinetics of color center formation in silica irradiated with swift heavy ions: Thresholding and formation efficiency

We have determined the cross-section σ for color center generation under single Br ion impacts on amorphous SiO2. The evolution of the cross-sections, σ(E) and σ(Se), show an initial flat stage that we associate to atomic collision mechanisms. Above a certain threshold value (Se > 2 keV/nm), roughly coinciding with that reported for the onset of macroscopic disorder (compaction), σ shows a marked increase due to electronic processes. In this regime, a energetic cost of around 7.5 keV is necessary to create a non bridging oxygen hole center-E′ (NBOHC/E′) pair, whatever the input energy. The data appear consistent with a non-radiative decay of self-trapped excitons

Cell-penetrating peptide-conjugated copper complexes for redox-mediated anticancer therapy

Metal-based chemotherapeutics like cisplatin are widely employed in cancer treatment. In the last years, the design of redox-active (transition) metal complexes, such as of copper (Cu), has attracted high interest as alternatives to overcome platinum-induced side-effects. However, several challenges are still faced, including optimal aqueous solubility and efficient intracellular delivery, and strategies like the use of cell-penetrating peptides have been encouraging. In this context, we previously designed a Cu(II) scaffold that exhibited significant reactive oxygen species (ROS)-mediated cytotoxicity. Herein, we build upon the promising Cu(II) redox-active metallic core and aim to potentiate its anticancer activity by rationally tailoring it with solubility- and uptake-enhancing functionalizations that do not alter the ROS-generating Cu(II) center. To this end, sulfonate, arginine and arginine-rich cell-penetrating peptide (CPP) derivatives have been prepared and characterized, and all the resulting complexes preserved the parent Cu(II) coordination core, thereby maintaining its reported redox capabilities. Comparative in vitro assays in several cancer cell lines reveal that while specific solubility-targeting derivatizations (i.e., sulfonate or arginine) did not translate into an improved cytotoxicity, increased intracellular copper delivery via CPP-conjugation promoted an enhanced anticancer activity, already detectable at short treatment times. Additionally, immunofluorescence assays show that the Cu(II) peptide-conjugate distributed throughout the cytosol without lysosomal colocalization, suggesting potential avoidance of endosomal entrapment. Overall, the systematic exploration of the tailored modifications enables us to provide further understanding on structure-activity relationships of redox-active metal-based (Cu(II)) cytotoxic complexes, which contributes to rationalize and improve the design of more efficient redox-mediated metal-based anticancer therapy

Low-Scale Expression and Purification of an Active Putative Iduronate 2-Sulfate Sulfatase-Like Enzyme from Escherichia coli K12

The sulfatase family involves a group of enzymes with a large degree of similarity. Until now, sixteen human sulfatases have been identified, most of them found in lysosomes. Human deficiency of sulfatases generates various genetic disorders characterized by abnormal accumulation of sulfated intermediate compounds. Mucopolysaccharidosis type II is characterized by the deficiency of iduronate 2-sulfate sulfatase (IDS), causing the lysosomal accumulation of heparan and dermatan sulfates. Currently, there are several cases of genetic diseases treated with enzyme replacement therapy, which have generated a great interest in the development of systems for recombinant protein expression. In this work we expressed the human recombinant IDS-Like enzyme (hrIDS-Like) in Escherichia coli DH5α. The enzyme concentration revealed by ELISA varied from 78. 13 to 94. 35 ng/ml and the specific activity varied from 34. 20 to 25. 97 nmol/h/mg. Western blotting done after affinity chromatography purification showed a single band of approximately 40 kDa, which was recognized by an IgY polyclonal antibody that was developed against the specific peptide of the native protein. Our 100 ml-shake-flask assays allowed us to improve the enzyme activity seven fold, compared to the E. coli JM109/pUC13-hrIDS-Like system. Additionally, the results obtained in the present study were equal to those obtained with the Pichia pastoris GS1115/pPIC-9-hrIDS-Like system (3 L bioreactor scale). The system used in this work (E. coli DH5α/pGEX-3X-hrIDS-Like) emerges as a strategy for improving protein expression and purification, aimed at recombinant protein chemical characterization, future laboratory assays for enzyme replacement therapy, and as new evidence of active putative sulfatase production in E. coli. © 2013 The Microbiological Society of Korea and Springer-Verlag Berlin Heidelberg.Fil: Morales Álvarez, Edwin David. Universidad del Quindio; ColombiaFil: Rivera Hoyos, Claudia Marcela. Universidad del Quindio. Facultad de Medicina; ColombiaFil: Baena Moncada, Angelica Maria. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba; ArgentinaFil: Landázuri, Patricia. Universidad del Quindio. Facultad de Medicina. Centro de Investig. Biomédicas; ColombiaFil: Poutou Piñales, Raúl A.. Pontificia Universidad Javeriana; ColombiaFil: Sáenz Suárez, Homero. Universidad del Quindio; ColombiaFil: Barrera, Luis A.. Pontificia Universidad Javeriana; ColombiaFil: Echeverri Peña, Olga Y.. Pontificia Universidad Javeriana; Colombi

Formation of hollow silver nanoparticles under irradiation with ultrashort laser pulses

9 pags., 5 figs.We have studied the formation of cavities in spherical silver nanoparticles embedded in silica, irradiated with fs laser pulses that produce an intense electronic excitation. Experimentally determined aspect ratio, i.e. the ratio between the cavity and nanoparticle size, for hollow structures formed under different irradiation conditions shows a very good agreement with values obtained by means of atomistic simulations. According to the predictions of the atomistic model, one can produce at will hollow silver nanoparticles with cavities of tailored dimensions, having an accurate control. Hence, laser irradiation can be used to control and design the optical response by tuning the localized surface plasmon resonances of the hollow nanoparticles.This work was partially funded by the regional government of Madrid through the TechnoFusion (III)-CM (S2018/EMT-4437) program, co-financed with Structural Funds (ERDF and ESF) and by the Projects PID2019-105325RB-C32 (Radiafus-5), PID2019-105156GB-I00, PID2021- 123228NB-I00 and PDC2022-133788-I00, funded by the Ministerio de Ciencia e Innovación of Spain. This work has also been partially funded by the Eurofusion consortium (EH150531176). JK was supported by the Beatriz Galindo Program (BEAGAL18/00130) from the Ministerio de Educación y Formación Profesional of Spain. This work was partially funded by Comunidad de Madrid through the Convenio Plurianual with Universidad Politécnica de Madrid in its line of action Apoyo a la realización de proyectos de I + D para investigadores Beatriz Galindo, within the framework of V PRICIT (V Plan Regional de Investigación Científica e Innovación Tecnológica). AP and FJV were supported by FONDECYT grant 3190123. MLC was supported by the research project “Captación de Talento UAM” Ref: #541D300 supervised by the Vice-Chancellor of Research of Universidad Autónoma de Madrid (UAM). The research leading to this result has been supported by the RADIATE project under the Grant Agreement 824096 from the EU Research and Innovation programme HORIZON 2020

Improvement of the Seminal Characteristics in Rams Using Agri-Food By-Products Rich in Phytomelatonin

The aim of this study was to evaluate the effect of a phytomelatonin-rich diet, including by-products from the food industry, on ram sperm quality and seminal plasma composition. Melatonin content in several by-products before and after in vitro ruminal and abomasal digestion was determined by HPLC-ESI-MS/MS. Finally, 20% of a mix of grape pulp with pomegranate and tomato pomaces was included in the rams’ diet, constituting the phytomelatonin-rich diet. Feeding the rams with this diet resulted in an increase in seminal plasma melatonin levels compared with the control group (commercial diet) in the third month of the study. In addition, percentages higher than those in the control group of morphologically normal viable spermatozoa with a low content of reactive oxygen species were observed from the second month onwards. However, the antioxidant effect does not seem to be exerted through the modulation of the antioxidant enzymes since the analysis of the activities of catalase, glutathione reductase and glutathione peroxidase in seminal plasma revealed no significant differences between the two experimental groups. In conclusion, this study reveals, for the first time, that a phytomelatonin-rich diet can improve seminal characteristics in ram

Recensiones [Revista de Historia Económica Año XVIII Otoño-Invierno 2000 n. 3 pp. 687-734]

Editada en la Fundación Empresa PúblicaColl, S., y Guijarro, M.: Estadística aplicada a las Ciencias Sociales (Por Daniel Peña).-- Tedde de Lorca, P.: El Banco de San Femando (1829-1856) (Por Carlos Marichal).-- Comín Comín, F., y Martín Aceña, P.: Tabacalera y el estanco de tabaco en España (1636-1998) (Por Lina Gálvez Muñoz).-- Millán García-Várela, J.: El poder de la tierra. La sociedad agraria del bajo Segura en la época del liberalismo (Por Ricardo Robledo).-- Matés Barco, J. M.: La conquista del agua. Historia económica del abastecimiento urbano (Por Beatriz Mera González).-- Ortiz Batalla, J.: Los Bancos Centrales en América Latina (Por Raúl García Heras).-- Guirao, F.: Spain and the Reconstruction of Western Europe, 1945-57: Challenge and Response (Por Jordi Catalán).-- Aghion, P., y Howitt, P.: Endogenous Growth Theory (Por Joan R. Rosés).-- Dye, A. D.: Cuban Sugar in the Age of Mass Production. Technology and the Economics of Sugar Central, 1899-1929 (Por Antonio Santamaría García).-- Gourvish, T. R., y Tiratsoo, N. (eds.): Missionaries and managers: American influences on European management education, 1945-60 (Por Nuria Puig).-- Coastworth, J., y Taylor, A. (eds.): Latin America and the World Economy since 1800 (Por Gustavo A. del Ángel-Mobarak)Publicad

Dosis de refuerzo con la vacuna BNT162b2 en población que recibió el esquema de vacunación completa para COVID-19 en Perú: Un análisis crítico de la evidencia actual

Background: In Peru, the current immunization schedule for COVID-19 includes BBIBP-CorV, BNT162B2 and ChAdOx1 nCoV-19 vaccines. Although the full immunization schedule is two doses, some countries have recently included a booster dose to their schedule. Methods: We conducted a search for scientific evidence on the efficacy and safety of booster vaccination with BNT162b2 vaccine in a population with a complete vaccination schedule for COVID-19 in Peru. Evidence: Four evidence-based recommendation documents, one observational study and three ongoing phase III clinical trials were included for analysis. Conclusion: To date, there is insufficient evidence on the efficacy of adding a booster dose to the immunization schedule for COVID-19. The available evidence does not justify the use of a booster dose of BNT162B2 vaccine in a population that has previously received two doses of the aforementioned vaccines.Introducción: En el Perú, el programa actual de inmunización para COVID-19 comprende las vacunas BBIBP-CorV, BNT162B2 y ChAdOx1 nCoV-19. Si bien el esquema de inmunización es de dos dosis, algunos países han incluido recientemente una dosis de refuerzo a su esquema. Métodos: Se realizó una búsqueda de evidencia científica sobre la eficacia y seguridad de la vacunación de refuerzo con la vacuna BNT162b2 en población con esquema de vacunación completa para COVID-19 en Perú. Evidencia incluida: Se consideraron cuatro documentos de recomendación basados en evidencia, un estudio observacional y tres ensayos clínicos fase III en curso. Conclusión: A la fecha, no existe evidencia suficiente sobre la eficacia de agregar una dosis de refuerzo al esquema de inmunización para COVID-19. La evidencia disponible no permite justificar el uso de una dosis de refuerzo con la vacuna BNT162B2 en población que recibió previamente dos dosis de las vacunas anteriormente mencionadas

Simulación mediante dinámica molecular de la irradiación de sílice con iones rápidos pesados

Simulación mediante dinámica molecular de la irradiación de sílice con iones rápidos pesado