This paper presents an overview of the parabolic-trough collectors that have been built and marketed during the past century, as well as the prototypes currently under development. It also presents a ...survey of systems which could incorporate this type of concentrating solar system to supply thermal energy up to 400°C, especially steam power cycles for electricity generation, including examples of each application.
Service-Learning is an educational methodology that allows student learning while addressing community needs. A program in microbiology and infectious diseases was implemented in Universidad ...Complutense de Madrid, Spain. University lecturers, clinical microbiologists, doctorate students, and undergraduates from several Bachelor Degrees and courses worked in an interdisciplinary team along with social institutions that attend disadvantaged persons. Using commercial movies that deal with infectious diseases, the students learn clinical microbiology, prepare divulgation materials, visit social centers to accompany, and help others to know about illnesses and prevention. The program was developed through two academic years and involved 58 voluntary students, 13 teachers and tutors, and 4 social entities as community partners. Postsurvey evaluation of the program revealed a highly satisfactory achievement of goals: acquiring scientific and personal competencies by university students, including critical analysis and science diffusion, solving problems or collaborative team working, and contributing, together with the tutors, to the social responsibility of the university.
Wetlands constitute the main natural source of methane on Earth due to their high content of natural organic matter (NOM), but key drivers, such as electron acceptors, supporting methanotrophic ...activities in these habitats are poorly understood. We performed anoxic incubations using freshly collected sediment, along with water samples harvested from a tropical wetland, amended with
C-methane (0.67 atm) to test the capacity of its microbial community to perform anaerobic oxidation of methane (AOM) linked to the reduction of the humic fraction of its NOM. Collected evidence demonstrates that electron-accepting functional groups (e.g., quinones) present in NOM fueled AOM by serving as a terminal electron acceptor. Indeed, while sulfate reduction was the predominant process, accounting for up to 42.5% of the AOM activities, the microbial reduction of NOM concomitantly occurred. Furthermore, enrichment of wetland sediment with external NOM provided a complementary electron-accepting capacity, of which reduction accounted for ∼100 nmol
CH
oxidized · cm
· day
Spectroscopic evidence showed that quinone moieties were heterogeneously distributed in the wetland sediment, and their reduction occurred during the course of AOM. Moreover, an enrichment derived from wetland sediments performing AOM linked to NOM reduction stoichiometrically oxidized methane coupled to the reduction of the humic analogue anthraquinone-2,6-disulfonate. Microbial populations potentially involved in AOM coupled to microbial reduction of NOM were dominated by divergent biota from putative AOM-associated archaea. We estimate that this microbial process potentially contributes to the suppression of up to 114 teragrams (Tg) of CH
· year
in coastal wetlands and more than 1,300 Tg · year
, considering the global wetland area.
The identification of key processes governing methane emissions from natural systems is of major importance considering the global warming effects triggered by this greenhouse gas. Anaerobic oxidation of methane (AOM) coupled to the microbial reduction of distinct electron acceptors plays a pivotal role in mitigating methane emissions from ecosystems. Given their high organic content, wetlands constitute the largest natural source of atmospheric methane. Nevertheless, processes controlling methane emissions in these environments are poorly understood. Here, we provide tracer analysis with
CH
and spectroscopic evidence revealing that AOM linked to the microbial reduction of redox functional groups in natural organic matter (NOM) prevails in a tropical wetland. We suggest that microbial reduction of NOM may largely contribute to the suppression of methane emissions from tropical wetlands. This is a novel avenue within the carbon cycle in which slowly decaying NOM (e.g., humic fraction) in organotrophic environments fuels AOM by serving as a terminal electron acceptor.
We used ionized gas and stellar kinematics for 667 spatially resolved galaxies publicly available from the Calar Alto Legacy Integral Field Area survey (CALIFA) third Data Release with the aim of ...studying kinematic scaling relations as the Tully & Fisher (TF) relation using rotation velocity, Vrot, the Faber & Jackson (FJ) relation using velocity dispersion, σ, and also a combination of Vrot and σ through the SK parameter defined as S2K=KV2rot+σ2 with constant K. Late-type and early-type galaxies reproduce the TF and FJ relations. Some early-type galaxies also follow the TF relation and some late-type galaxies the FJ relation, but always with larger scatter. On the contrary, when we use the SK parameter, all galaxies, regardless of the morphological type, lie on the same scaling relation, showing a tight correlation with the total stellar mass, M⋆. Indeed, we find that the scatter in this relation is smaller or equal to that of the TF and FJ relations. We explore different values of the K parameter without significant differences (slope and scatter) in our final results with respect to the case K= 0.5 besides a small change in the zero-point. We calibrate the kinematic S2K dynamical mass proxy in order to make it consistent with sophisticated published dynamical models within 0.15 dex. We show that the SK proxy is able to reproduce the relation between the dynamical mass and the stellar mass in the inner regions of galaxies. Our result may be useful in order to produce fast estimations of the central dynamical mass in galaxies and to study correlations in large galaxy surveys.
Obesity and the risk of cardiometabolic diseases Valenzuela, Pedro L; Carrera-Bastos, Pedro; Castillo-García, Adrián ...
Nature reviews cardiology,
07/2023, Letnik:
20, Številka:
7
Journal Article
Recenzirano
The prevalence of obesity has reached pandemic proportions, and now approximately 25% of adults in Westernized countries have obesity. Recognized as a major health concern, obesity is associated with ...multiple comorbidities, particularly cardiometabolic disorders. In this Review, we present obesity as an evolutionarily novel condition, summarize the epidemiological evidence on its detrimental cardiometabolic consequences and discuss the major mechanisms involved in the association between obesity and the risk of cardiometabolic diseases. We also examine the role of potential moderators of this association, with evidence for and against the so-called 'metabolically healthy obesity phenotype', the 'fatness but fitness' paradox or the 'obesity paradox'. Although maintenance of optimal cardiometabolic status should be a primary goal in individuals with obesity, losing body weight and, particularly, excess visceral adiposity seems to be necessary to minimize the risk of cardiometabolic diseases.
Objective
To characterize the incidence and prevalence of childhood‐onset systemic lupus erythematosus (SLE), and to estimate the proportion of patients who are diagnosed with SLE during childhood.
...Methods
A cohort of patients with incident childhood‐onset SLE from 1976 to 2018 from an 8‐county region in the US were identified based on comprehensive medical record review. All patients met the European Alliance of Associations for Rheumatology (EULAR)/American College of Rheumatology (ACR) classification criteria for SLE or the ACR SLE classification criteria from 1997 at or before age 18 years. Incidence rates were estimated using Poisson methods. We estimated the childhood‐onset SLE point prevalence for January 1, 2015. Results were sex and age adjusted to the US 2000 population. Among all the SLE patients living in the 8‐county region on January 1, 2015, the proportion of patients diagnosed at ≤18 years was estimated.
Results
A total of 13 children were diagnosed with childhood‐onset SLE during the study period (using the EULAR/ACR definition; mean age at diagnosis 15.1 years, 85% female, 69% White). Childhood‐onset SLE overall adjusted incidence rate was 0.7 (95% confidence interval 95% CI 0.2–1.1) per 100,000 children. The incidence rate in girls was 1.2 (95% CI 0.5–1.9) per 100,000 children, while in boys it was 0.2 (95% CI 0.0–0.5) per 100,000. The adjusted prevalence of childhood‐onset SLE was 1.1 (95% CI 0.0–3.1) per 100,000 children. The proportion of patients with SLE diagnosed as children was 9% (95% CI 6–13%).
Conclusion
In this population‐based study, both the incidence and prevalence rates of childhood‐onset SLE were ~1 per 100,000 children. One in 10 adults with SLE was diagnosed in childhood. More studies are needed to further characterize the epidemiology of childhood‐onset SLE in minorities.
Rapid degradation of fresh‐cut papaya limits its marketability. Hydrothermal treatments in combination with a calcium dip, applied to whole fruit before slicing, and also the application of chitosan ...as a coating film, have been found to have very good results in maintaining the quality of fresh‐cut fruits. Based on these considerations, the aim of this study was to evaluate the effect of hydrothermal treatment (HT; 49 °C, 25 min) containing calcium chloride (Ca; 1%, w/v) followed by dipping in chitosan (Chit; 1%, w/v, 3 min) on the physical, chemical, and microbial qualities of papaya slices stored at 5 °C for 10 d. Pulp color, firmness, ascorbic acid, total phenolics, β‐carotene, and lycopene were evaluated every 2 d while the microbial quality (mesophilics, psychrophilics, molds, and yeasts) was evaluated every 5 d. Fruit treated with HT‐Ca and HT‐Ca + Chit showed better color and firmness retention than Control and Chit. Papaya slices treated with HT‐Ca + Chit had higher nutritional content and lower microbial growth at the end of storage. The application of the HT‐Ca + Chit could be used to reduce deterioration processes, maintaining physical, chemical, and microbial qualities and increasing the shelf life of fresh‐cut papaya stored at 5 °C.
Practical Application
The application of hydrothermal‐calcium chloride, combined with chitosan coatings, reduced deterioration processes and presented antimicrobial activity, thus increasing the shelf life and showing its potential use in food preservation. Also, it can constitute an alternative for the natural preservation of fresh‐cut papaya for which the use of synthetic chemicals is objectionable.
Abstract
We introduce the Automatic Learning for the Rapid Classification of Events (ALeRCE) broker, an astronomical alert broker designed to provide a rapid and self-consistent classification of ...large etendue telescope alert streams, such as that provided by the Zwicky Transient Facility (ZTF) and, in the future, the Vera C. Rubin Observatory Legacy Survey of Space and Time (LSST). ALeRCE is a Chilean-led broker run by an interdisciplinary team of astronomers and engineers working to become intermediaries between survey and follow-up facilities. ALeRCE uses a pipeline that includes the real-time ingestion, aggregation, cross-matching, machine-learning (ML) classification, and visualization of the ZTF alert stream. We use two classifiers: a stamp-based classifier, designed for rapid classification, and a light curve–based classifier, which uses the multiband flux evolution to achieve a more refined classification. We describe in detail our pipeline, data products, tools, and services, which are made public for the community (see
https://alerce.science
). Since we began operating our real-time ML classification of the ZTF alert stream in early 2019, we have grown a large community of active users around the globe. We describe our results to date, including the real-time processing of 1.5 × 10
8
alerts, the stamp classification of 3.4 × 10
7
objects, the light-curve classification of 1.1 × 10
6
objects, the report of 6162 supernova candidates, and different experiments using LSST-like alert streams. Finally, we discuss the challenges ahead in going from a single stream of alerts such as ZTF to a multistream ecosystem dominated by LSST.
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