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The analysis of proteins in the gas phase benefits from detectors that exhibit high efficiency and precise spatial resolution. Although modern secondary electron multipliers already address numerous analytical requirements, additional methods are desired for macromolecules at energies lower than currently used in post-acceleration detection. Previous studies have proven the sensitivity of superconducting detectors to high-energy particles in time-of-flight mass spectrometry. Here, we demonstrate that superconducting nanowire detectors are exceptionally well suited for quadrupole mass spectrometry and exhibit an outstanding quantum yield at low-impact energies. At energies as low as 100 eV, the sensitivity of these detectors surpasses conventional ion detectors by three orders of magnitude, and they offer the possibility to discriminate molecules by their impact energy and charge. We demonstrate three developments with these compact and sensitive devices, the recording of 2D ion beam profiles, photochemistry experiments in the gas phase, and advanced cryogenic electronics to pave the way toward highly integrated detectors.
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This report highlights the combination of the MicroTime 100 upright confocal fluorescence lifetime microscope with a Single Quantum Eos Superconducting Nanowire Single-Photon Detector (SNSPD) system as a powerful tool for photophysical research and applications. We focus on an application in materials science, photoluminescence imaging, and lifetime characterization of Cu(InGa)Se2 (CIGS) devices intended for solar cells. We demonstrate improved sensitivity, signal-to-noise ratio, and time-resolution in combination with confocal spatial resolution in the near-infrared (NIR) range, specifically in the 1000-1300 nm range. The MicroTime 100-Single Quantum Eos system shows two orders of magnitude higher signal-to-noise ratio for CIGS devices' photoluminescence imaging compared to a standard NIR-photomultiplier tube (NIR-PMT) and a three-fold improvement in time resolution, which is now limited by the laser pulse width. Our results demonstrate the advantages in terms of image quality and time resolution of SNSPDs technology for imaging in materials science.
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Native platelets are crucial players in wound healing. Key to their role is the ability of their surface receptor GPIIb/IIIa to bind fibrin at injury sites, thereby promoting clotting. When platelet activity is impaired as a result of traumatic injury or certain diseases, uncontrolled bleeding can result. To aid clotting and tissue repair in cases of poor platelet activity, our lab has previously developed synthetic platelet-like particles capable of promoting clotting and improving wound healing responses. These are constructed by functionalizing highly deformable hydrogel microparticles (microgels) with fibrin-binding ligands including a fibrin-specific whole antibody or a single-domain variable fragment. To improve the translational potential of these clotting materials, we explored the use of fibrin-binding peptides as cost-effective, robust, high-specificity alternatives to antibodies. Herein, we present the development and characterization of soft microgels decorated with the peptide AHRPYAAK that mimics fibrin knob 'B' and targets fibrin hole 'b'. These "Fibrin-Affine Microgels with Clotting Yield" (FAMCY) were found to significantly increase clot density in vitro and decrease bleeding in a rodent trauma model in vivo. These results indicate that FAMCYs are capable of recapitulating the platelet-mimetic properties of previous designs while utilizing a less costly, more translational design.
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El seminoma es la neoplasia testicular más frecuente alcanzando hasta el 50% de todos los casos de cancer del testículo. Dependiendo de su naturaleza, seminomatoso o no seminomatoso, las conductas de manejo y tratamiento médico quirúrgicas varían según los centros, los protocolos de manejo y la experiencia de los equipos de atención. Objetivos. Promover la discusión de adyuvancia o neoadyuvancia en caso de seminoma clásico. Paciente y Método. Presentar un caso de seminoma clásico tratado quirúrgicamente con orquidectomía y una década después se presenta con extensión metastásica mediastinal y retroperitoneal. Conclusiones. Para la etiología no seminomatosa, se establece la orquidectomía seguida de vigilancia; mientras que en caso de origen seminomatoso la discusión se basa en el momento del rol de la cirugía, radiación y quimioterapia, por lo tanto, se debe individualizar cada paciente según las características clínicas manifestadas. (AU)
Seminoma is the most common testicular neoplasm, reaching up to 50% of all cases of testicular cancer. Depending on its nature, seminomatous or non-seminomatous, the management behaviors and surgical medical treatment vary according to the centers, the management protocols and the experience of the care teams. Objective. Promote the discussion of adjuvant or neoadjuvant in case of classic seminoma. Patient and Method. To present a case of classic seminoma treated surgically with orchidectomy and a decade later it presents with mediastinal and retroperitoneal metastatic extension. Conclusions. For non-seminomatous etiology, orchidectomy followed by surveillance is established; while in the case of seminomatous origin, the discussion is based on the time of the role of surgery, radiation and chemotherapy, therefore, each patient must be individualized according to the clinical characteristics manifested. (AU)
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Humanos , Masculino , Adulto , Neoplasias Testiculares/fisiopatología , Seminoma/diagnóstico , Metástasis de la Neoplasia/genética , Teratoma/clasificación , Testículo/patología , Radiografía/métodosRESUMEN
Simultaneous MIMO-free transmission of 12 orbital angular momentum (OAM) modes over a 1.2 km air-core fiber is demonstrated. WDM compatibility of the system is shown by using 60, 25 GHz spaced WDM channels with 10 GBaud QPSK signals. System performance is evaluated by measuring bit error rates, which are found to be below the soft FEC limit, and limited by inter-modal crosstalk. The crosstalk in the system is analyzed, and it is concluded that it can be significantly reduced with an improved multiplexer and de-multiplexer.
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Quantum key distribution (QKD) and quantum communication enable the secure exchange of information between remote parties. Currently, the distributed-phase-reference (DPR) protocols, which are based on weak coherent pulses, are among the most practical solutions for long-range QKD. During the last 10 years, long-distance fiber-based DPR systems have been successfully demonstrated, although fundamental obstacles such as intrinsic channel losses limit their performance. Here, we introduce the first two-dimensional DPR-QKD protocol in which information is encoded in the time and phase of weak coherent pulses. The ability of extracting two bits of information per detection event, enables a higher secret key rate in specific realistic network scenarios. Moreover, despite the use of more dimensions, the proposed protocol remains simple, practical, and fully integrable.
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Mode-division multiplexing has the potential to further increase data transmission capacity through optical fibers. In addition, distributed Raman amplification is a promising candidate for multi-mode signal amplification due to its desirable noise properties and the possibility of mode-equalized gain. In this paper, we present an experimental characterization of the intermodal Raman intensity overlaps of a few-mode fiber using backward-pumped Raman amplification. By varying the input pump power and the degree of higher order mode-excitation for the pump and the signal in a 10 km long two-mode fiber, we are able to characterize all intermodal Raman intensity overlaps. Using these results, we perform a Raman amplification measurement and demonstrate a mode-differential gain of only 0.25 dB per 10 dB overall gain. This is, to the best of our knowledge, the lowest mode differential gain achieved for amplification of mode division multiplexed signals in a single fiber.
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Redes de Comunicación de Computadores , Equipos y Suministros/normas , Algoritmos , Atención a la Salud/organización & administración , Equipos y Suministros de Hospitales , Humanos , Programas Controlados de Atención en Salud/organización & administración , Informática Médica , Ciencia del Laboratorio Clínico , Sistemas de Registros Médicos Computarizados , Modelos Organizacionales , Procesamiento de Señales Asistido por Computador , Interfaz Usuario-ComputadorRESUMEN
Evidence of the physical existence of the spatial coherence moiré is obtained by confronting numerical results with experimental results of spatially partial interference. Although it was performed for two particular cases, the results reveal a general behavior of the optical fields in any state of spatial coherence. Moreover, the study of the spatial coherence moiré deals with a new type of filtering, named filtering of classes of radiator pairs, which allows changing the power spectrum at the observation plane by modulating the complex degree of spatial coherence, without altering the power distribution at the aperture plane or introducing conventional spatial filters. This new procedure can optimize some technological applications of actual interest, as the beam shaping for instance.
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We indirectly evaluated the selective pressures on dispersal and establishment of Campsiandra angustifolia, a common water-dispersed tree from the Peruvian Amazon, analyzing the variation in the relationship between the volume occupied by dispersal and establishment structures in a total of 535 seeds from 13 trees located at three different habitats. The seeds differed one order of magnitude in their total volume. However, independently of their size and the location of the maternal tree, the relationship between the volume occupied by dispersal and establishment structures was relatively constant (~1) and showed a normal distribution with low skewness, indicating stabilizing selection. These results suggest that, in the habitats studied, dispersal and establishment processes may have similar importance to C.angustifolia. In species with seeds confined in pods, and therefore strongly space-limited, the relative volume of their seeds occupied by dispersal and establishment structures could be a better measure of the trade-off between these two processes than the variation in seed size
Evaluamos indirectamente las presiones selectivas sobre la dispersión y el establecimiento en Campsiandra angustifolia, un árbol de la Amazonía Peruana dispersado por agua, analizando variaciones de la relación entre el volumen ocupado por las estructuras de dispersión y de establecimiento en sus semillas. Medimos un total de 535 semillas de 13 árboles ubicados en tres hábitats diferentes, las cuales presentaron una gran variación en su volumen total. Independientemente del tamaño de la semilla y de la ubicación del árbol de origen, la relación entre el volumen asignado a estructuras de establecimiento y a estructuras de dispersión fue relativamente constante (~1) y presentó una distribución normal con baja asimetría, indicando selección estabilizante. Este resultado sugiere que los procesos de dispersión y establecimiento poseen una importancia relativa similar para C.angustifolia en los hábitats estudiados. En especies con semillas empaquetadas, el volumen relativo ocupado por estructuras relacionadas con la dispersión o el establecimiento podría ser una medida más adecuada de la solución de compromiso entre estos dos procesos que la variación del tamaño de la semilla
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Ecosistema , Fabaceae/fisiología , Germinación/fisiología , Selección Genética , Semillas/fisiología , Árboles/fisiología , Tamaño Corporal/fisiología , Cotiledón/fisiología , Desastres , Fabaceae/anatomía & histología , Relámpago , Perú , Estaciones del Año , Plantones/fisiología , Semillas/anatomía & histologíaRESUMEN
We indirectly evaluated the selective pressures on dispersal and establishment of Campsiandra angustifolia, a common water-dispersed tree from the Peruvian Amazon, analyzing the variation in the relationship between the volume occupied by dispersal and establishment structures in a total of 535 seeds from 13 trees located at three different habitats. The seeds differed one order of magnitude in their total volume. However, independently of their size and the location of the maternal tree, the relationship between the volume occupied by dispersal and establishment structures was relatively constant (approximately 1) and showed a normal distribution with low skewness, indicating stabilizing selection. These results suggest that, in the habitats studied, dispersal and establishment processes may have similar importance to C. agustifolia. In species with seeds confined in pods, and therefore strongly space-limited, the relative volume of their seeds occupied by dispersal and establishment structures could be a better measure of the trade-off between these two processes than the variation in seed size.
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Ecosistema , Fabaceae/fisiología , Germinación/fisiología , Semillas/fisiología , Selección Genética , Tamaño Corporal/fisiología , Cotiledón/fisiología , Desastres , Fabaceae/anatomía & histología , Relámpago , Perú , Estaciones del Año , Plantones/fisiología , Semillas/anatomía & histologíaAsunto(s)
Glaucoma/fisiopatología , Apoptosis , Degeneración Nerviosa , Óxido Nítrico , Regeneración NerviosaRESUMEN
De las neoplasias germinales del ovario nosotros decidimos investigar de una manera retrospectiva el tumor tipo disgerminoma, por ser el más frecuente, para lo cual revisamos los casos tratados en el Instituto Nacional de Cancerología INCAN de 1990 a 1997 recurriendo al Departamento de Estadística y al libro de informes de patología habiendo encontrado un total de 15 casos. Encontramos en nuestro estudio que este tumor afecta principalmente a mujeres jóvenes en edad reproductiva (12 casos que equivalen a un 80); 8 casos (53.3) corresponden a pacientes menores de 20 años reportamos como dato interesante que todas tenían paridad de "0" al momento de ser llevadas a cirugía, a 4 se les efectuó HSOB (histerosalpingooforectomía bilateral) a 2 histerectomía y en las 2 restantes SOD (salpingooforectomía derecha), conservándose fertilidad únicamente en estas dos últimas pacientes. Observamos que la mayoría de casos provenía de los departamentos o fueron operadas en hospitales con poca experiencia oncológica, lo que influyó al final en el manejo quirúrgico de las pacientes. Después de 7 años de seguimiento de las 15 pacientes estudiadas 10 (66.7) se encuentran vivas y de las 5 (33.3) restantes no se encontró información en los expedientes clínicos. Después de ser operadas 9 pacientes (60) recibieron quimioterapia, 3 (20) radioterapia y 3 (20) no regresaron al hospital. Basados en los resultados alcanzados podemos concluír y recomendar que la meta principal en pacientes con diagnóstico de disgerminoma será la curación con la conservación de su fertilidad aún en estadíos avanzados. La quimioterapia será el tratamiento recomendado como primera línea después de efectuada la cirugía dejando la radioterapia para pacientes que habiendo recibido el tratamiento anterior todavía presentan enfermedad residual o que por alguna contraindicación no pueden recibir quimioterapia