293 research outputs found

    Estudio de la Asfaltita y aplicaciones en mezclas asfálticas tibias y semitibias

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    The use of natural asphalt represents an innovative alternative for the creation of asphalt mixtures; Currently, Colombian regulations present applications of this type of asphalt as both in base and in granular sub-bases, and in asphalt mixtures, but the application that has been given for the design of asphalt mixtures has not been able to exploit all the benefits of the material since it is often used in an inappropriate way. The purpose of this research article is to expose the main characteristics of natural asphalt and the possible alternatives that could be studied when including it in the manufacture of a warm (WMA) or half warm (HWMA) asphalt mix; It also includes the natural asphalt deposits found in the world and in Colombia. The environmental benefits of the implementation of this type of mixtures are exposed, stating that the use of these technologies helps to reduce greenhouse gas emissions and combustion gases. In addition, it contributes to the reduction of the depletion of finite resources due to the fact that this type of asphalt mixtures are manufactured and compacted at lower temperatures, as well as the consumption of manufactured asphalt, products of petroleum distillation is reduced.El uso de los asfaltos naturales representa una alternativa innovadora para la creación de mezclas asfálticas. Actualmente, en la normativa colombiana hay aplicaciones de este tipo de asfalto tanto en base como en subbases granulares y en mezclas asfálticas, pero la que se le ha dado al diseño de mezclas asfálticas no ha logrado explotar todos los beneficios del material, ya que se suele utilizar de manera inadecuada. El artículo tiene como propósito exponer las principales características del asfalto natural y las posibles alternativas que se podrían llegar a estudiar al incluirla en la fabricación de un mezcla asfáltica tibia (WMA) o semitibia (HWMA); además, se incluyen los yacimientos de asfalto natural que se encuentran en el mundo y en Colombia. Se exponen los beneficios ambientales de la implementación de este tipo de mezclas, planteando que el uso de estas tecnologías ayuda a disminuir las emisiones de gases de efecto invernadero y gases de combustión, y que contribuye a la disminución del agotamiento de los recursos finitos, debido a que este tipo de mezclas asfálticas se fabrican y se compactan a menores temperaturas. También se reduce el consumo de asfaltos manufacturados, productos de la destilación del petróleo.

    Catálogo de las umbeliferas "apiaceae" malacitanas (Málaga, España)

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    Se ha realizado un catálogo de las umbelíferas (Apiaceae) presentes en la provincia de Málaga (Andalucía, España). De cada uno de los 103 táxones citados (44 géneros) indicamos su localidad, referencia bibliográfica y pliegos de herbarios. Así mismo se realiza un análisis del comportamiento ecológico de cada uno de ellos, de su ubicación biogeográfica en la provincia y de la diversidad taxonómica

    Alcohol, smoking, recreational drug use and association with virological outcomes among people living with HIV: cross-sectional and longitudinal analyses

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    Objectives: There is increasing evidence to suggest that people living with HIV (PLWH) have significant morbidity from alcohol, recreational drug use and cigarette smoking. Our aim was to report associations of these factors with antiretroviral therapy (ART) non-adherence, viral non-suppression and subsequent viral rebound in PLWH. / Methods: The Antiretroviral Sexual Transmission Risk and Attitudes (ASTRA) study recruited PLWH attending eight outpatient clinics in England between February 2011 and December 2012. Data included self-reported excessive drinking (estimated consumption of > 20 units of alcohol/week), alcohol dependency (CAGE score ≥ 2 with current alcohol consumption), recreational drug use (including injection drug use in the past 3 months), and smoking status. Among participants established on ART, cross-sectional associations with ART non-adherence [missing ≥2 consecutive days of ART on ≥2 occasions in the past three months] and viral-non suppression [viral load (VL) > 50 copies/mL] were assessed using logistic regression. In participants from one centre, longitudinal associations with subsequent viral rebound (first VL > 200 copies/mL) in those on ART with VL ≤ 50 copies/mL at baseline were assessed using Cox regression during a 7-year follow-up. / Results: Among 3258 PLWH, 2248 (69.0%) were men who have sex with men, 373 (11.4%) were heterosexual men, and 637 (19.6%) were women. A CAGE score ≥ 2 was found in 568 (17.6%) participants, 325 (10.1%) drank > 20 units/week, 1011 (31.5%) currently smoked, 1242 (38.1%) used recreational drugs and 74 (2.3%) reported injection drug use. In each case, prevalence was much more common among men than among women. Among 2459 people on ART who started at least 6 months previously, a CAGE score ≥ 2, drinking > 20 units per week, current smoking, injection and non-injection drug use were all associated with ART non-adherence. After adjusting for demographic and socioeconomic factors, CAGE score ≥ 2 [adjusted odds ratio (aOR) = 1.52, 95% confidence interval (CI): 1.09–2.13], current smoking (aOR = 1.58, 95% CI: 1.10–2.17) and injection drug use (aOR = 2.11, 95% CI: 1.00–4.47) were associated with viral non-suppression. During follow-up of a subset of 592 people virally suppressed at recruitment, a CAGE score ≥ 2 [adjusted hazard ratio (aHR) = 1.66, 95% CI: 1.03–2.74], use of 3 or more non-injection drugs (aHR = 1.82, 95% CI: 1.12–3.57) and injection drug use (aHR = 2.73, 95% CI: 1.08–6.89) were associated with viral rebound. / Conclusions: Screening and treatment for alcohol, cigarette and drug use should be integrated into HIV outpatient clinics, while clinicians should be alert to the potential for poorer virological outcomes

    Assessment of non-adherence to external radiotherapy treatment in cancer patients in Catalonia,Spain

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    Purpose or Objective: Non-adherence to external radiotherapy is an aspect of treatment which has not been fully explored. The objective of this study is to analyse the relevance of this problem and its impact on 1-year surviva

    Impact of non-adherence to radiotherapy on 1-year survival in cancer patients in Catalonia, Spain

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    Background: This study aims to assess the effects of non-adherence to external beam radiation therapy in cancer patients receiving treatment with a curative. Methods: This retrospective cohort study collected health records data for all cancer patients treated with external beam radiotherapy with curative intent in 2016 in Catalonia, Spain. Adherence was defined as having received at least 90% of the total dose prescribed. A logistic regression model was used to assess factors related to non-adherence, and its association with one-year survival was evaluated using Cox regression. Results: The final sample included 8721 patients (mean age 63.6 years): breast cancer was the most common tumour site (38.1%), followed by prostate and colon/rectum. Treatment interruptions prolonged the total duration of therapy in 70.7% of the patients, and 1.0% were non-adherent. Non-adherence was associated with advanced age, female gender, and some localization of primary tumour (head and neck, urinary bladder, and haematological cancers). The risk of death in non-adherent patients was higher than in adherent patients (hazard ratio [HR] 1.63, 95% confidence interval 0.97-2.74), after adjusting for the potential confounding effect of age, gender, tumour site and comorbidity. Conclusion: Non-adherence to radiotherapy, as measured by the received dose, is very low in our setting, and it may have an impact on one-year survival

    Antibacterial and Antifungal Activity of Functionalized Cotton Fabric with Nanocomposite Based on Silver Nanoparticles and Carboxymethyl Chitosan

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    Cotton is the most widely used natural fiber for textiles; however, the capacity of cotton fibers to absorb large amounts of moisture, retain oxygen, and have a high specific surface area makes them more prone to microbial contamination, becoming an appropriate medium for the growth of bacteria and fungi. In recent years, the incorporation of silver nanoparticles in textile products has been widely used due to their broad-spectrum antibacterial activity and low toxicity towards mammalian cells. The aim of the current study is to continue the assessment of our developed nanocomposite and evaluate the antibacterial and antifungal activity of the nanocomposite based on silver nanoparticles and carboxymethyl chitosan (AgNPs-CMC) against Escherichia coli, Staphylococcus aureus, and Candida albicans, evaluated by the well diffusion method. The antibacterial activity against E. coli and S. aureus was also evaluated by the qualitative method of inhibition zone and the quantitative method of colony counting. Likewise, the antifungal activity of the functionalized fabric against Candida albicans and Aspergillus niger was determined by the inhibition zone method and the antifungal activity method GBT 24346-2009, respectively. The functionalized fabric showed 100% antibacterial activity against E. coli and S. aureus and good antifungal activity against C. albicans and A. niger. Our results indicate that the functionalized fabric could be used in garments for hospital use to reduce nosocomial infections

    High prevalence of strongyloidiasis in spain : A hospital-based study

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    Strongyloidiasis is a prevailing helminth infection ubiquitous in tropical and subtropical areas, however, seroprevalence data are scarce in migrant populations, particularly for those coming for Asia. This study aims at evaluating the prevalence of S. stercoralis at the hospital level in migrant populations or long term travellers being attended in out-patient and in-patient units as part of a systematic screening implemented in six Spanish hospitals. A cross-sectional study was conducted and systematic screening for S. stercoralis infection using serological tests was offered to all eligible participants. The overall seroprevalence of S. stercoralis was 9.04% (95%CI 7.76-10.31). The seroprevalence of people with a risk of infection acquired in Africa and Latin America was 9.35% (95%CI 7.01-11.69), 9.22% (7.5-10.93), respectively. The number of individuals coming from Asian countries was significantly smaller and the overall prevalence in these countries was 2.9% (95%CI −0.3-6.2). The seroprevalence in units attending potentially immunosuppressed patients was significantly lower (5.64%) compared with other units of the hospital (10.20%) or Tropical diseases units (13.33%) (p < 0.001). We report a hospital-based strongyloidiasis seroprevalence of almost 10% in a mobile population coming from endemic areas suggesting the need of implementing strongyloidiasis screening in hospitalized patients coming from endemic areas, particularly if they are at risk of immunosuppression

    The Amazon Epiphyte Network: A First Glimpse Into Continental-Scale Patterns of Amazonian Vascular Epiphyte Assemblages

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    Epiphytes are still an understudied plant group in Amazonia. The aim of this study was to identify distributional patterns and conservation priorities for vascular epiphyte assemblages (VEA) across Amazonia. We compiled the largest Amazonian epiphyte plot database to date, through a multinational collaborative effort of 22 researchers and 32 field sites located across four Amazonian countries – the Amazonian Epiphyte Network (AEN). We addressed the following continental-scale questions by utilizing the AEN database comprising 96,448 epiphyte individuals, belonging to 518 vascular taxa, and growing on 10,907 tree individuals (phorophytes). Our objectives here are, first, to present a qualitative evaluation of the geographic distribution of the study sites and highlight regional lacunae as priorities for future quantitative inventories. Second, to present the floristic patterns for Amazonia-wide VEA and third, to combine multivariate analyses and rank abundance curves, controlled by major Amazonian habitat types, to determine how VEA vary geographically and ecologically based on major Amazonian habitat types. Three of the most striking patterns found are that: (1) VEA are spatially structured as floristic similarity decays with geographic distance; (2) a core group of 22 oligarchic taxa account for more than a half of all individuals; and (3) extensive floristic sampling gaps still exist, mainly across the highly threatened southern Amazonian deforestation belt. This work represents a first step toward unveiling distributional pattern of Amazonian VEA, which is important to guide future questions on ecology and species distribution ranges of VEA once the collaborative database grows allowing a clearer view of patterns
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