Physics for non-physicists - Two bio-degrees reforms in Spanish universities: Health Biology and Biology

We present a review of two different innovative experiences of Physics education for Bio-Sciences in two Spanish Universities - the Health Biology degree of the Universidad de Alcalá de Henares (UAH) and the Biology degree of the Universidad Autónoma de Madrid (UAM). Both experiences took place simultaneously and coincident with the implementation of Bologna Plan. Although they were developed under different contextual constraints, set by the respective Faculties, they share a number of similar pedagogical strategies which are analyzed. In both cases the reforms allowed a substantial improvement in learning results compared to those obtained in the previous Physics courses in the respective degreesLHM participated in the GIREP-MPTL 2018 on behalf of the project IPLS-Spain, promoted and supported by an inter-university group of physics teachers and young biologist

Diameter selective characterization of single-wall carbon nanotubes

A novel method is presented which allows the characterization of diameter selective phenomena in SWCNTs. It is based on the transformation of fullerene peapod materials into double-wall carbon nanotubes and studying the diameter distribution of the latter. The method is demonstrated for the diameter selective healing of nanotube defects and yield from C$_{70}$ peapod samples. Openings on small diameter nanotubes are closed first. The yield of very small diameter inner nanotubes from C$_{70}$ peapods is demonstrated. This challenges the theoretical models of inner nanotube formation. An anomalous absence of mid-diameter inner tubes is observed and explained by the suppressed amount of C$_{70}$ peapods due to the competition of the two almost equally stable standing and lying C$_{70}$ peapod configurations

Algorithmic Interpretations of Fractal Dimension

We study algorithmic problems on subsets of Euclidean space of low fractal dimension. These spaces are the subject of intensive study in various branches of mathematics, including geometry, topology, and measure theory. There are several well-studied notions of fractal dimension for sets and measures in Euclidean space. We consider a definition of fractal dimension for finite metric spaces which agrees with standard notions used to empirically estimate the fractal dimension of various sets. We define the fractal dimension of some metric space to be the infimum delta>0, such that for any eps>0, for any ball B of radius r >= 2eps, and for any eps-net N, we have |B cap N|=O((r/eps)^delta). Using this definition we obtain faster algorithms for a plethora of classical problems on sets of low fractal dimension in Euclidean space. Our results apply to exact and fixed-parameter algorithms, approximation schemes, and spanner constructions. Interestingly, the dependence of the performance of these algorithms on the fractal dimension nearly matches the currently best-known dependence on the standard Euclidean dimension. Thus, when the fractal dimension is strictly smaller than the ambient dimension, our results yield improved solutions in all of these settings. We remark that our definition of fractal definition is equivalent up to constant factors to the well-studied notion of doubling dimension. However, in the problems that we consider, the dimension appears in the exponent of the running time, and doubling dimension is not precise enough for capturing the best possible such exponent for subsets of Euclidean space. Thus our work is orthogonal to previous results on spaces of low doubling dimension; while algorithms on spaces of low doubling dimension seek to extend results from the case of low dimensional Euclidean spaces to more general metric spaces, our goal is to obtain faster algorithms for special pointsets in Euclidean space

Antiproliferative Oleanane Saponins from Dizygotheca elegantissima

Four new oleanane saponins (1-4), together with three known saponins, were isolated from the aerial parts of Dizygotheca elegantissima R. Vig. & Guillaumin. Their structures were elucidated by 1D and 2D NMR experiments including 1D TOCSY, DQF-COSY, HSQC, and HMBC spectroscopy, as well as ESIMS analysis. The antiproliferative activity of all isolated compounds was evaluated

Thermoelectric properties of polypropylene carbon nanofiber melt-mixed composites: exploring the role of polymer on their Seebeck coefficient

The effect of polypropylene (PP) on the Seebeck coefficient (S) of carbon nanofibers (CNFs) in melt-extruded PP composites filled with up to 5 wt. % of CNFs was analyzed in this study. The as-received CNFs present an electrical conductivity of ~320 S m−1 and an interesting phenomenon of showing negative S-values of −5.5 μVK−1, with 10−2 µW/mK2 as the power factor (PF). In contrast, the PP/CNF composites with 5 wt. % of CNFs showed lower conductivities of ~50 S m−1, less negative S-values of −3.8 μVK−1, and a PF of 7 × 10−4 µW/mK2. In particular, the change in the Seebeck coefficient of the PP/CNF composites is explained by a slight electron donation from the outer layers of the CNFs to the PP molecules, which could reduce the S-values of the as-received CNFs. Our study indicates that even insulating polymers such as PP may have a quantifiable effect on the intrinsic Seebeck coefficient of carbon-based nanostructures, and this fact should also be taken into consideration to tailor conductive polymer composites with the desired thermoelectric (TE) properties.The authors affiliated with 2C2T acknowledge support from FCT-Foundation for Science and Technology within the scope of project UID/CTM/00264/2020. In addition, support through project IF/ A. J. Paleo et al. 00894/2015 and within the scope of the project CICECO-Aveiro Institute of Materials, UIDB/50011/2020 and UIDP/50011/2020 and access to the Navigator platform (LCA-UC) through the Advanced Computing Project CPCA/A2/2524/2020, financed by national funds through the Portuguese Foundation for Science and Technology I.P./ MCTES, is gratefully acknowledged

Blastic plasmacytoid dendritic cell neoplasm: Genomics mark epigenetic dysregulation as a primary therapeutic target

Blastic plasmacytoid dendritic cell neoplasm (BPDCN) is a rare and aggressive hematologic malignancy for which there is still no effective B therapy. In order to identify genetic alterations useful for a new treatment design, we used whole-exome sequencing to analyze 14 BPDCN patients and the patient-derived CAL-1 cell line. The functional enrichment analysis of mutational data reported the epigenetic regulatory program to be the most significantly undermined (P<0.0001). In particular, twenty-five epigenetic modifiers were found mutated (e.g. ASXL1, TET2, SUZ12, ARID1A, PHF2, CHD8); ASXL1 was the most frequently affected (28.6% of cases). To evaluate the impact of the identified epigenetic mutations at the gene-expression and Histone H3 lysine 27 trimethylation/acetylation levels, we performed additional RNA and pathology tissue-chromatin immunoprecipitation sequencing experiments. The patients displayed enrichment in gene signatures regulated by methylation and modifiable by decitabine administration, shared common H3K27-acetylated regions, and had a set of cell-cycle genes aberrantly up-regulated and marked by promoter acetylation. Collectively, the integration of sequencing data showed the potential of a therapy based on epigenetic agents. Through the adoption of a preclinical BPDCN mouse model, established by CAL-1 cell line xenografting, we demonstrated the efficacy of the combination of the epigenetic drugs 5’-azacytidine and decitabine in controlling disease progression in vivo

Dynamics of phytoplankton species composition, biomass and nutrients in the North Atlantic during spring and summer - A trans-Atlantic study

During a return trip in May–June 2013 from Bergen, Norway, to Nuuk, Greenland, on the Institute of Marine Research's R/V “G. O. Sars”, four ocean basins, the Norwegian, Iceland, Irminger and Labrador seas, were surveyed twice. Here we analyse the phytoplankton communities and their dynamics in the four basins, winter nutrient content, potential for new production, consumption of nutrients, phenology and algae biomass (Chlorophyll a). The primary production dynamics of the four basins are compared and related to physical forcing and top-down control and discussed in relation to vertical carbon flux. We focus on the primary production dynamics in the central, mostly Atlantic, water masses of the basin-wide gyres. The survey results are put into a larger scale context by comparison with MODIS surface chlorophyll estimates. The timing of the phytoplankton bloom phase differed among the basins. In the Labrador Sea, there was a strong bloom already occurring during the first crossing in mid-May. This was confirmed by nitrate and silicate reduction, which was much larger in the Labrador Sea compared to the other seas in May. In the Irminger Sea the bloom lagged behind, whereas in the Norwegian and Iceland seas both a pre-bloom and a late bloom were observed during May–June. There was a direct relationship between the mixed layer depth and the use of nitrate at the sampling stations, and a direct relationship between chlorophyll concentrations and the use of nitrate. The two relationships suggest that the use of nitrate can serve as a measure of the developmental state of the phytoplankton bloom, phenology, and that it is related to the shallowing of the mixed layer. Flagellates were the most abundant algae in all regions, outnumbered by diatoms only at a couple of stations west of Greenland. Elevated ciliate numbers were observed in the Iceland and Norwegian seas on both sides of the Arctic front. The algae outnumbered the microzooplankton by at least an order of magnitude.publishedVersio

Self-reported health needs and use of primary health care services by adolescents enrolled in post-mandatory schools or vocational training programmes in Switzerland.

BACKGROUND: The second Swiss Multicenter Adolescent Survey on Health (SMASH02) was conducted among a representative sample (n = 7428) of students and apprentices aged 16 to 20 from the three language areas of Switzerland during the year 2002. This paper reports on health needs expressed by adolescents and their use of health care services over the 12 months preceding the survey. METHODS: Nineteen cantons representing 80% of the resident population agreed to participate. A complex iterative random cluster sample of 600 classes was drawn with classes as primary sampling unit. The participation rate was 97.7% for the classes and 99.8% for the youths in attendance. The self-administered questionnaire included 565 items. The median rate of item non-response was 1.8%. Ethical and legal requirements applying to surveys of adolescent populations were respected. RESULTS: Overall more than 90% of adolescents felt in good to excellent health. Suffering often or very often from different physical complaints or pain was also reported such as headache (boys: 15.9%, girls: 37.4%), stomach-ache (boys: 9.7%, girls: 30.0%), joint pain (boys: 24.7%, girls: 29.5%) or back pain (boys: 24.3%, girls: 34.7%). Many adolescents reported a need for help on psychosocial and lifestyle issues, such as stress (boys: 28.5%, girls: 47.7%) or depression (boys: 18.9%, girls: 34.4%). Although about 75% of adolescents reported having consulted a general practitioner and about one-third having seen another specialist, reported reasons for visits do not correspond to the expressed needs. Less than 10% of adolescents had visited a psychiatrist, a family planning centre or a social worker. CONCLUSIONS: The reported rates of health services utilisation by adolescents does not match the substantial reported needs for help in various areas. This may indicate that the corresponding problems are not adequately detected and/or addressed by professionals from the health and social sectors

Identification of sex hormone-binding globulin in the human hypothalamus

Gonadal steroids are known to influence hypothalamic functions through both genomic and non-genomic pathways. Sex hormone-binding globulin ( SHBG) may act by a non-genomic mechanism independent of classical steroid receptors. Here we describe the immunocytochemical mapping of SHBG-containing neurons and nerve fibers in the human hypothalamus and infundibulum. Mass spectrometry and Western blot analysis were also used to characterize the biochemical characteristics of SHBG in the hypothalamus and cerebrospinal fluid (CSF) of humans. SHBG-immunoreactive neurons were observed in the supraoptic nucleus, the suprachiasmatic nucleus, the bed nucleus of the stria terminalis, paraventricular nucleus, arcuate nucleus, the perifornical region and the medial preoptic area in human brains. There were SHBG-immunoreactive axons in the median eminence and the infundibulum. A partial colocalization with oxytocin could be observed in the posterior pituitary lobe in consecutive semithin sections. We also found strong immunoreactivity for SHBG in epithelial cells of the choroid plexus and in a portion of the ependymal cells lining the third ventricle. Mass spectrometry showed that affinity-purified SHBG from the hypothalamus and choroid plexus is structurally similar to the SHBG identified in the CSF. The multiple localizations of SHBG suggest neurohypophyseal and neuroendocrine functions. The biochemical data suggest that CSF SHBG is of brain rather than blood origin. Copyright (c) 2005 S. Karger AG, Base