1,065 research outputs found

    Fourier transform microwave spectroscopy of Ac-Ser-NH2: the role of side chain interactions in peptide folding

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    Serine capped dipeptide N-acetyl-L-serinamide (Ac-Ser-NH2) has been investigated using Fourier transform microwave spectroscopic techniques combined with laser ablation sources. Spectral signatures originating from one dominant species have been detected in the supersonic expansion. Rotational and nuclear quadrupole coupling constants of the two 14N nuclei have been used in the characterization of a Ceq/g-turn structure, which is stabilized by a C7O·· ·HN intramolecular hydrogen bond closing a seven-membered ring. Two extra hydrogen bonds involving the polar side chain (–CH2OH) further stabilize the structure. The non-observation of C5 species, attributed to the presence of the polar side chain, is in contrast with the previous gas phase observation of the related dipeptides containing glycine or alanine residues. The A–E splitting pattern arising from the internal rotation of the methyl group has been analyzed and the internal rotation barrier has been determined

    Early Evaluation of Mobile Applications’ Resource Consumption and Operating Costs

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    The explosive growth of the mobile application market in recent years has led to a large concomitant mobile software industry whose components are, in many cases, startups and small-size software providers. The success of these applications and the firms behind them depends on a subtle balance between different dimensions mainly affected by their architectural design, such as user satisfaction, resource consumption, operating costs, and timing. The present communication describes a framework with a specific set of practices for identifying the boundaries of different architectural designs —in this article we apply it to estimate both the smartphone’s resource consumption and the operating costs in the cloud— and thus help in the architectural decision-making process. This will enable mobile software developers to predict at early stages which architectural design best suits their business model in accordance with the number of users and the expected use of the application and even provide an advance alert of when architectural choices will need to be reviewed, obviating the need for costly architectural re-design in further phasesMinisterio de Ciencia, Innovación y Universidades RTI2018-094591-B-I00Ministerio de Ciencia, Innovación y Universidades PGC2018-094905-B-I00Junta de Andalucía APOLO (US-1264651)Ministerio de Ciencia e Innovación HORATIO (RTI2018-101204–B–C21)Ministerio de Ciencia, Innovación y Universidades RED2018-102654-TInterreg V-A España-Portugal (POCTEP) 0499-4IE-PLUS-4-EJunta de Andalucía UMA18-FEDERJA-180Junta de Extremadura GR18112Junta de Extremadura IB1803

    Correlator implementation for orthogonal CSS used in an ultrasonic LPS

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    This paper presents a new architecture for the correlation of orthogonal complementary sets of sequences (OCSS) and their performance in an ultrasonic local positioning system (U-LPS). OCSS are sets of sequences whose addition of correlation functions has ideal properties, that makes interference-free code-division multiple access (CDMA) possible. They can be used to encode the signals emitted by a CDMA based U-LPS, enhancing the performance of such systems in terms of immunity against noise, multipath propagation, and near-far effect. Also, the orthogonality of the codes offers an operation resistance to multiaccess interference, which endows the U-LPS with the capability of simultaneous emission from different beacons. On the other hand, the detection of OCSS codes can be performed by means of efficient algorithms. This paper presents an optimization of previous proposals allowing the simultaneous correlation of OCSS by using fewer operations and memory elements. Furthermore, the hardware implementation of the proposed optimization is also addressed, and an U-LPS based on this proposal is presented.Fil: Peréz Rubio, M. Carmen. Universidad de Alcalá; EspañaFil: Sanz Serrano, Rebeca. Universidad de Alcalá; EspañaFil: Ureña Ureña, Jesús. Universidad de Alcalá; EspañaFil: Hernández Alonso, Álvaro. Universidad de Alcalá; EspañaFil: de Marziani, Carlos Manuel. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Álvarez Franco, Fernando J.. Universidad Nacional de la Patagonia "San Juan Bosco". Facultad de Ingeniería - Sede Comodoro; Argentin

    ANÁLISIS DE INGENIERÍA DE REQUERIMIENTOS: ALTA DE UNIDADES DE APRENDIZAJE EN LA UAI-UAGRO (MÉXICO)

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    En la actualidad, para la aplicación de ingeniería de software existen varios procesos de desarrollo de software. En esta investigación una de las etapas importantes del proceso de desarrollo es la ingeniería de requerimientos, etapa en que se definen inicialmente las características y restricciones con las que debe contar el sistema en desarrollo, parte fundamental ya que determina qué funcionalidad debe contener el software. En el caso de uso se aplicará al Sistema de Alta de Unidades de Aprendizaje (SAUA), que les permitirá a los alumnos de la Unidad Académica de Ingeniería (UAI) de la Universidad Autónoma de Guerrero (UAGro) dar de alta la unidad de aprendizaje ofertada (cursos) de manera remota mediante el uso de internet.

    Ciguatoxin occurrence in food-web components of a Cuban Coral Reef Ecosystem: Risk-assessment implications

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    In Cuba, ciguatera poisoning associated with fish consumption is the most commonly occurring non-bacterial seafood-borne illness. Risk management through fish market regulation has existed in Cuba for decades and consists of bans on selected species above a certain weight; however, the actual occurrence of ciguatoxins (CTXs) in seafood has never been verified. From this food safety risk management perspective, a study site locally known to be at risk for ciguatera was selected. Analysis of the epiphytic dinoflagellate community identified the microalga Gambierdiscus. Gambierdiscus species included six of the seven species known to be present in Cuba (G. caribaeus, G. belizeanus, G. carpenteri, G. carolinianus, G. silvae, and F. ruetzleri). CTX-like activity in invertebrates, herbivorous and carnivorous fishes were analyzed with a radioligand receptor-binding assay and, for selected samples, with the N2A cell cytotoxicity assay. CTX activity was found in 80% of the organisms sampled, with toxin values ranging from 2 to 8 ng CTX3C equivalents g−1 tissue. Data analysis further confirmed CTXs trophic magnification. This study constitutes the first finding of CTX-like activity in marine organisms in Cuba and in herbivorous fish in the Caribbean. Elucidating the structure–activity relationship and toxicology of CTX from the Caribbean is needed before conclusions may be drawn about risk exposure in Cuba and the wider Caribbean.info:eu-repo/semantics/publishedVersio

    The role of the surface acidic/basic centers and redox sites on TiO2 in the photocatalytic CO2 reduction

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    The development of sustainable processes for CO reduction to fuels and chemicals is one of the most important challenges to provide clean energy solutions. The use of sunlight as renewable energy source is an interesting alternative to power the electron transfer required for artificial photosynthesis. Even if redox sites are mainly responsible for this process, other reactive acidic/basic centers also contribute to the overall reaction pathway. However, a full understanding of the CO photoreduction mechanism is still a scientific challenge. In fact, the lack of agreement on standardized comparison criteria leads to a wide distribution of reported productions, even using the same catalyst, which hinders a reliable interpretation. An additional difficulty is ascertaining the origin of carbon-containing products and effect of surface carbon residues, as well as the reaction intermediates and products under real dynamic conditions. To determine the elusive reaction mechanism, we report an interconnected strategy combining in-situ spectroscopies, theoretical studies and catalytic experiments. These studies show that CO photoreduction productions are influenced by the presence of carbon deposits (i.e. organic molecules, carbonates and bicarbonates) over the TiO surface. Most importantly, the acid/base character of the surface and the reaction medium play a key role in the selectivity and deactivation pathways. This TiO deactivation is mainly initiated by the formation of carbonates and peroxo- species, while activity can be partially recovered by a mild acid washing treatment. We anticipate that these findings and methodology enlighten the main shadows still covering the CO reduction mechanism, and, most importantly, provide essential clues for the design of emergent materials and reactions for photo(electro)catalytic energy conversion

    Population Characteristics of Human-Commensal Rodents Present in Households from Mérida, Yucatán, México

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    Anthropocommensal rodents live in close proximity to humans in many habitats around the world. They are a threat to public health because of the pathogens they carry. Recent studies in Mérida, Yucatán, México, have shown that commensal rodents harbor potential zoonotic pathogens such as bacteria, helminths, and viruses. In this study, we describe reproductive and demographic parameters of house mice and black rats present in households from Mérida, Yucatán, México, a municipality located in a tropical region in southern México. Rodents were trapped in 142 households within the municipality of Mérida from 2011 to 2014. A total of 832 rodents were trapped, constituting 556 (66.8%) house mice (Mus musculus) and 276 (33.2%) black rats (Rattus rattus). The sex ratio in mice was different than parity, while in rats it was 1:1. Mice in the weight class 8.1–12 g were most abundant in both females (52.9%) and males (57.2%). On the other hand, rats weighing ≤ 40 g (25% of females and 28.6% of males) were most abundant. The percentage of pregnancy in mice was 46.7%, whereas in rats it was 21.3%. The mean number of embryos was 4.7 and 5.8 in mice and rats, respectively. This study provides relevant demographic information on the ecology of commensal rodents from a tropical region of Latin America. We consider that our findings could be useful as a first step toward understanding the ecological behavior of rodent populations in tropical regions

    Elaboración de recursos docentes para la enseñanza presencial y semipresencial en el área de la Ingeniería Química empleando Jupyter Notebook

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    El objetivo principal de este proyecto es la elaboración de recursos docentes, para estudiantes y profesores, dentro del área de la Ingeniería Química, utilizando el software libre Jupyter Notebook, empleado bajo el lenguaje de programación Python

    Biological significance of monoallelic and biallelic BIRC3 loss in del(11q) chronic lymphocytic leukemia progression

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    © The Author(s) 2021.BIRC3 is monoallelically deleted in up to 80% of chronic lymphocytic leukemia (CLL) cases harboring del(11q). In addition, truncating mutations in the remaining allele of this gene can lead to BIRC3 biallelic inactivation, which has been shown to be a marker for reduced survival in CLL. Nevertheless, the biological mechanisms by which these lesions could contribute to del(11q) CLL pathogenesis and progression are partially unexplored. We implemented the CRISPR/Cas9-editing system to generate isogenic CLL cell lines harboring del(11q) and/or BIRC3 mutations, modeling monoallelic and biallelic BIRC3 loss. Our results reveal that monoallelic BIRC3 deletion in del(11q) cells promotes non-canonical NF-κB signaling activation via RelB-p52 nuclear translocation, being these effects allelic dose-dependent and therefore further enhanced in del(11q) cells with biallelic BIRC3 loss. Moreover, we demonstrate ex vivo in primary cells that del(11q) cases including BIRC3 within their deleted region show evidence of non-canonical NF-κB activation which correlates with high BCL2 levels and enhanced sensitivity to venetoclax. Furthermore, our results show that BIRC3 mutations in del(11q) cells promote clonal advantage in vitro and accelerate leukemic progression in an in vivo xenograft model. Altogether, this work highlights the biological bases underlying disease progression of del(11q) CLL patients harboring BIRC3 deletion and mutation.This work was supported by grants from the Spanish Fondo de Investigaciones Sanitarias PI15/01471, PI18/01500, Instituto de Salud Carlos III (ISCIII), European Regional Development Fund (ERDF) “Una manera de hacer Europa”, “Consejería de Educación, Junta de Castilla y León” (SA271P18), “Proyectos de Investigación del SACYL”, Spain GRS 2062/A/19, GRS 1847/A/18, GRS1653/A17,“Fundación Memoria Don Samuel Solórzano Barruso” (FS/23-2018), by grants (RD12/0036/0069) from Red Temática de Investigación Cooperativa en Cáncer (RTICC), Universidad de Salamanca (Programa XIII), Centro de Investigación Biomédica en Red de Cáncer (CIBERONC CB16/12/00233) and SYNtherapy “Synthetic Lethality for Personalized Therapy-based Stratification In Acute Leukemia” (ERAPERMED2018-275); ISCIII (AC18/00093), co-funded by ERDF/ESF, “Investing in your future”. M.Q.Á. and A.E.R.V. are supported with a research grant by FEHH (“Fundación Española de Hematología y Hemoterapia”); M.H.S. holds a Sara Borrell postdoctoral contract (CD19/00222) from the Instituto de Salud Carlos III (ISCIII). C.P.C. was supported by an “Ayuda predoctoral en Oncología” (AECC) and is a recipient of a PFIS grant (FI19/00191) from Instituto de Salud Carlos III; PFIS grant and Sara Borrell postdoctoral contrat are co-founded by Fondo Social Europeo (FSE) “El Fondo Social Europeo invierte en tu futuro”; J.L.O. and R.B.S. are supported by a grant from the University of Salamanca (“Contrato postdoctoral programa II”)

    Multisensor experiments over vineyard: new challenges for the GNSS-R technique

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    An airborne campaign was performed during August, 2014 in an agricultural area in the Duero basin (Spain) in order to appraise the synergy between very different sources of Earth Observation imagery, and very different instruments for soil moisture retrieval. During the flight, an intensive field campaign comprising soil, plant and spectral measurements was carried out. An innovative sensor based on the Global Navigation Satellite Systems Reflectometry (GNSS-R) was on board the manned vehicle, the Light Airborne Reflectometer for GNSS-R Observations (LARGO) engineered by the Universitat Politècnica de Catalunya. While the synergy between thermal, optical and passive microwave spectra observations is well known for vegetation parameters and soil moisture retrievals, the experiment aimed to evaluate the synergy of GNSS-R reflectivity with a time-collocated Landsat 8 imagery for soil moisture retrieval under semiarid climatic conditions. LARGO estimates, field measurements, and optical, NIR, SWIR and thermal bands from Landsat 8 were compared. Results showed that the joint use of GNSS-R reflectivity with vegetation and water indices together with thermal maps from Landsat 8 thoroughly improved the soil moisture estimation.Peer ReviewedPostprint (published version
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