EH Performance of an Hybrid Energy Harvester for Autonomous Nodes

This paper reports the Energy Harvesting (EH) performance of a hybrid energy harvester able to collect energy form different energy sources: thermal, solar and electromagnetic. The main block of the system is the quarter-wavelength patch antenna, operating in the Industrial, Scientific and Medical (ISM) frequency band 2.4-2.5 GHz. The antenna has been designed and optimized to support a Thermo-Electric Generator (TEG) and a Solar Cell on its top. Moreover, a rectifier has been designed to work with the antenna and a DC-DC converter has been used to manage the TEG output voltage

Identification of two new repetitive elements and chromosomal mapping of repetitive DNA sequences in the fish Gymnothorax unicolor (Anguilliformes: Muraenidae)

Muraenidae is a species-rich family, with relationships among genera and species and taxonomy that have not been completely clarified. Few cytogenetic studies have been conducted on this family, and all of them showed the same diploid chromosome number (2n=42) but with conspicuous karyotypic variation among species. The Mediterranean moray eel Gymnothorax unicolor was previously cytogenetically studied using classical techniques that allowed the characterization of its karyotype structure and the constitutive heterochromatin and argyrophilic nucleolar organizer regions (Ag-NORs) distribution pattern. In the present study, we describe two new repetitive elements (called GuMboI and GuDdeI) obtained from restricted genomic DNA of G. unicolor that were characterized by Southern blot and physically localized by in situ hybridization on metaphase chromosomes. As they are highly repetitive DNA sequences, they map in heterochromatic regions. However, while GuDdeI was localized in the centromeric regions, the GuMboI fraction was distributed on some centromeres and was co-localized with the nucleolus organizer region (NOR). Comparative analysis with other Mediterranean species such as Muraena helena pointed out that these DNA fractions are species-specific and could potentially be used for species discrimination. As a new contribution to the karyotype of this species, we found that the major ribosomal genes are localized on acrocentric chromosome 9 and that the telomeres of each chromosome are composed of a tandem repeat derived from a poly-TTAGGG DNA sequence, as it occurs in most vertebrate species. The results obtained add new information useful in comparative genomics at the chromosomal level and contribute to the cytogenetic knowledge regarding this fish family, which has not been extensively studied

A Novel Luciferase-Based Reporter Gene Technology for Simultaneous Optical and Radionuclide Imaging of Cells

Multimodality reporter gene imaging combines the sensitivity, resolution and translational potential of two or more signals. The approach has not been widely adopted by the animal imaging community, mainly because its utility in this area is unproven. We developed a new complementation-based reporter gene system where the large component of split NanoLuc luciferase (LgBiT) presented on the surface of cells (TM-LgBiT) interacts with a radiotracer consisting of the high-affinity complementary HiBiT peptide labeled with a radionuclide. Radiotracer uptake could be imaged in mice using SPECT/CT and bioluminescence within two hours of implanting reporter-gene-expressing cells. Imaging data were validated by ex vivo biodistribution studies. Following the demonstration of complementation between the TM-LgBiT protein and HiBiT radiotracer, we validated the use of the technology in the highly specific in vivo multimodal imaging of cells. These findings highlight the potential of this new approach to facilitate the advancement of cell and gene therapies from bench to clinic.</p

Whole-body bioluminescence imaging of T-cell response in PDAC models

IntroductionThe location of T-cells during tumor progression and treatment provides crucial information in predicting the response in vivo.MethodsHere, we investigated, using our bioluminescent, dual color, T-cell reporter mouse, termed TbiLuc, T-cell location and function during murine PDAC tumor growth and checkpoint blockade treatment with anti-PD-1 and anti-CTLA-4. Using this model, we could visualize T-cell location and function in the tumor and the surrounding tumor microenvironment longitudinally. We used murine PDAC clones that formed in vivo tumors with either high T-cell infiltration (immunologically ‘hot’) or low T-cell infiltration (immunologically ‘cold’).ResultsDifferences in total T-cell bioluminescence could be seen between the ‘hot’ and ‘cold’ tumors in the TbiLuc mice. During checkpoint blockade treatment we could see in the tumor-draining lymph nodes an increase in bioluminescence on day 7 after treatment.ConclusionsIn the current work, we showed that the TbiLuc mice can be used to monitor T-cell location and function during tumor growth and treatment

Low-Noise Ku-Band Receiver Frontend with Switchable SIW Filters for Cubesat Applications

This paper proposes a low-noise receiver frontend for nanosatellite and Cubesat platforms. The frontend is composed by a Low-Noise Amplifier (LNA) and two Substrate Integrated Waveguide (SIW) filters, providing a frequency reconfigurability to the system. The two filters operate in the 13 and in the 14 GHz uplink bands, and are selected by means of a pair of solid-state SPDT switches. As a results, 15.5 dB gain with 2.4 dB noise figure for the 13 GHz configuration and 17.8 dB gain with 2.3 dB noise figure for the 14 GHz configuration are obtained. This work is important since demonstrates a low-cost solution for satellite radio apparatuses based on commercial components on a standard PCB

Low-Noise Block Downconverter based on COTS and SIW Filters for Ku-band Cubesat Transponders

This paper proposes a Low-Noise Block (LNB) downconverter operating in the Ku-band for Cubesat transponders. The frontend is composed by a Low-Noise Amplifier (LNA) and two switchable Substrate Integrated Waveguide (SIW) filters, providing a frequency reconfigurability to the system. The LNB is completed by a downconversion unit, constituted by a mixer, a PLL frequency synthesizer and an IF amplifier. A first breadboard features an overall gain of 54 dB with a 2.3 dB noise figure. The worst case linearity performance indicates an input-referred 1 dB compression point (P1dB) and a third-order intercept point (IIP3) equal to -27 dBm and -16 dBm respectively. This work is important since demonstrates a low-cost solution for satellite radio apparatuses based on commercial components and standard PCB

Comparación de la actividad mitótica de las células epiteliales tubulares, en dos zonas del riñón de ratones machos adultos posnefrectomía

La nefrectomía unilateral (Nx) generalmente, está asociada con degeneración a largo término del riñón remanente. Es sabido que la remoción de un riñón estimula inmediatamente el crecimiento y la función del otro pero, hay diferentes mecanismos que inician el crecimiento compensatorio renal (CCR) dependiendo en parte de la edad, del sexo y de la zona analizada. Algunos autores demostraron que en ratones de ambos sexos, durante las primeras horas siguientes a la Nx, hay un periodo inicial de crecimiento hiperplásico aunque, solamente en el compartimiento cortical. Sin embargo, en trabajos previos nosotros observamos que a las 50 horas de la Nx, los valores de ADNs de las células tubulares corticales (CTC) y de la médula externa (CTM), son similares a los de los ratones intactos y a los de los animales falsamente nefrectomizados (F Nx), en ambos sexos.Facultad de Ciencias Médica

Click beetle luciferase mutant and near infrared naphthyl-luciferins for improved bioluminescence imaging

The sensitivity of bioluminescence imaging in animals is primarily dependent on the amount of photons emitted by the luciferase enzyme at wavelengths greater than 620 nm where tissue penetration is high. This area of work has been dominated by firefly luciferase and its substrate, D-luciferin, due to the system's peak emission (~ 600 nm), high signal to noise ratio, and generally favorable biodistribution of D-luciferin in mice. Here we report on the development of a codon optimized mutant of click beetle red luciferase that produces substantially more light output than firefly luciferase when the two enzymes are compared in transplanted cells within the skin of black fur mice or in deep brain. The mutant enzyme utilizes two new naphthyl-luciferin substrates to produce near infrared emission (730 nm and 743 nm). The stable luminescence signal and near infrared emission enable unprecedented sensitivity and accuracy for performing deep tissue multispectral tomography in mice

Protons in near earth orbit

The proton spectrum in the kinetic energy range 0.1 to 200 GeV was measured by the Alpha Magnetic Spectrometer (AMS) during space shuttle flight STS-91 at an altitude of 380 km. Above the geomagnetic cutoff the observed spectrum is parameterized by a power law. Below the geomagnetic cutoff a substantial second spectrum was observed concentrated at equatorial latitudes with a flux ~ 70 m^-2 sec^-1 sr^-1. Most of these second spectrum protons follow a complicated trajectory and originate from a restricted geographic region.Comment: 19 pages, Latex, 7 .eps figure