149 research outputs found

    Total Synthesis of Asparenydiol by Two Sonogashira Cross-Coupling Reactions Promoted by Supported Pd and Cu Catalysts

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    Asparenydiol, which is an important natural compound with potential pharmacological activities, was synthesized through two Sonogashira cross-coupling reactions catalyzed by supported Pd and Cu catalysts and by a Mitsunobu etherification. The optimization of the Sonogashira couplings allowed the use of catalysts supported on different matrices with good results in terms of catalytic efficiency and yields

    Identification and synthesis of new sex-specific components of olive fruit fly (Bactrocera oleae) female rectal gland, through original Negishi reactions on supported catalysts

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    In the present study, eleven new sex-specific components extracted from female rectal gland of olive fruit flies were synthesized and identified. The quantitative determination of those components by GC and GC/EI-MS, at different moments of the insect life span, highlighted the growing trend of their secretion. While for the synthesis of saturated esters, conventional transesterification methods could be adopted, for the synthesis of unsaturated components, a Negishi cross-coupling between organozinc halides and (Z)-1-bromo-1-alkenes was developed. To the extent of our knowledge, this reaction represents the first example of supported-catalyst promoted Negishi coupling, between an alkylzinc reagent and an alkenyl halide

    Peer support between healthcare workers in hospital and out-of-hospital settings: a scoping review

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    Background and aim: the healthcare workers, mostly in emergency departments, are exposed to emotionally strong situations: this condition often can lead them to operate incorrectly. In the face of the mistake, many of them experience psychological trauma, becoming “second victims” of the event. In this case they can find comfort in dealing with Peers that can help to understand emotions and normalize lived experiences. A scoping review was conducted to clarify the key concepts available in the literature and understand Peer Support characteristics and methods of implementation. Methods: scoping review approach of Joanna Briggs Institute was used. The reviewers analyzed the last twenty-one years of literature and extracted data from relevant studies. Results: 49 articles were relevant. Articles involve mostly physicians and nurses, but all the other healthcare professionals are included. 56% of the articles have been published in the last two years during the Covid 19 pandemic, which revealed the growing need of developing Peer Support programs; the Anglo-Saxon countries are the main geographical area of origin (82%). Peer support emerges as a preclinical psychological support for people involved in tiring situations. It’s based on mutual respect and on voluntary and not prejudicial help. Peers are trained to guide the support relationship. Peer Support can be proposed as one to one/group peer support, or through online platforms. Conclusions: many of the studies affirm that the personnel involved have benefited from the programs available. It is necessary to carry out further research to determine the pre and post intervention benefits. (www.actabiomedica.it)

    Successful implementation of inquiry-based physiology laboratories in undergraduate major and nonmajor courses. Adv Physiol Educ 32

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    Casotti G, Rieser-Danner L, Knabb MT. Successful implementation of inquiry-based physiology laboratories in undergraduate major and nonmajor courses. Adv Physiol Educ 32: 286-296, 2008; doi:10.1152/advan.00100.2007.-Recent evidence has demonstrated that inquiry-based physiology laboratories improve students' criticaland analytical-thinking skills. We implemented inquiry-based learning into three physiology courses: Comparative Vertebrate Physiology (majors), Human Physiology (majors), and Human Anatomy and Physiology (nonmajors). The aims of our curricular modifications were to improve the teaching of physiological concepts, teach students the scientific approach, and promote creative and critical thinking. We assessed our modifications using formative (laboratory exams, oral presentations, and laboratory reports) and summative evaluations (surveys, laboratory notebook, and an end of semester project). Students appreciated the freedom offered by the new curriculum and the opportunity to engage in the inquiry process. Results from both forms of evaluation showed a marked improvement due to the curricular revisions. Our analyses indicate an increased confidence in students' ability to formulate questions and hypotheses, design experiments, collect and analyze data, and make conclusions. Thus, we have successfully incorporated inquiry-based laboratories in both major and nonmajor courses. pedagogy; curriculum; evaluation INQUIRY-BASED LEARNING is an alternative pedagogical method of classroom teaching that is characterized by a focus on learning through discovery. It incorporates four approaches to teaching: 1) a focus on ideas and concepts generated by students rather than by instructors, 2) an activity component where students actively participate in performing tasks (experiments) to test their ideas, 3) an emphasis on learning the methods of verifying and testing hypotheses, and 4) an emphasis on the importance of both content and process as components of learning Some individual studies of the effectiveness of an inquirybased approach have been reported. For example, DiPasquale et al. (2) modified the curriculum in an exercise physiology course at San Diego State University. The course was previously taught in a traditional style. Their new approach was to cover core exercise physiology topics in the first third of the course using the traditional teacher-centered style of learning while emphasizing the scientific process. In the last 9 wk of the course, students worked in small groups of three to four and completed independent research projects. In contrast, Myers and Burgess (11) redesigned an organismal physiology course centering on student-designed experiments throughout the course of the semester. Both studies reported an increase in student achievement of learning outcomes using student-designed experiments compared with a teacher-centered approach. Moreover, a recent review (10) published in Advances of Physiology Education summarized the evidence supporting the conclusion that forms of active learning, such as an inquirybased approach, are more effective in enhancing student learning than traditional modes of teaching. Problems With the Existing Curriculum The physiology curriculum using a teacher-centered approach resulted in several problems related to student learning. One of the problems was that students in our nonmajor course failed to connect physiological concepts taught in lecture with the laboratory activities. In addition, the laboratories did not emphasize the scientific approach to problem solving, and students were restricted in the types of experiments they were able to perform (13). Our old curriculum provided students with detailed step-bystep instructions for completing their experiments. As a result, students commented to the laboratory instructors that they lost sight of the educational purpose of the experiments. Furthermore, regimented instructions did not allow our students any flexibility to deviate from the experimental protocol, thereby impeding student creativity Students had no opportunity to develop their own understanding of physiology using the scientific approach. Even though our majors were required to write laboratory reports in prerequisite courses such as Cell Physiology and Organic Chemistry, they did not communicate their ideas effectively in a scientific report. For example, students did not refer to the neural control of respiration when discussing irregular respiratory patterns when solving a math problem. This resulted in low scores on laboratory reports. Clearly, this called for the need to offer students more opportunities using the scientific method, from researching background information to developing a testable hypothesis using appropriate written communication and reporting of scientific findings. Similar problems in understanding the scientific approach were also evident in our nonmajor course (see Precurricula Survey). Verbal comments from students in our physiology courses indicated a dissatisfaction with simply repeating experiments that had already been done by other researchers. Students could not see the purpose of performing some of the experiments, especially those involving animals, and often asked "Why ar

    Deep sequencing of amplified Prasinovirus and host green algal genes from an Indian Ocean transect reveals interacting trophic dependencies and new genotypes

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    International audienceHigh-throughput sequencing of Prasinovirus DNA polymerase and host green algal (Mamiellophyceae) ribosomal RNA genes was used to analyse the diversity and distribution of these taxa over a ∼10 000 km latitudinal section of the Indian Ocean. New viral and host groups were identified among the different trophic conditions observed, and highlighted that although unknown prasinoviruses are diverse, the cosmopolitan algal genera Bathycoccus, Micromonas and Ostreococcus represent a large proportion of the host diversity. While Prasinovirus communities were correlated to both the geography and the environment, host communities were not, perhaps because the genetic marker used lacked sufficient resolution. Nevertheless, analysis of single environmental variables showed that eutrophic conditions strongly influence the distributions of both hosts and viruses. Moreover, these communities were not correlated, in their composition or specific richness. These observations could result from antagonistic dynamics, such as that illustrated in a prey–predator model, and/or because hosts might be under a complex set of selective pressures. Both of these reasons must be considered to interpret environmental surveys of viruses and hosts, because covariation does not always imply interaction

    European marine omics biodiversity observation network: a strategic outline for the implementation of omics approaches in ocean observation

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    Marine ecosystems, ranging from coastal seas and wetlands to the open ocean, accommodate a wealth of biological diversity from small microorganisms to large mammals. This biodiversity and its associated ecosystem function occurs across complex spatial and temporal scales and is not yet fully understood. Given the wide range of external pressures on the marine environment, this knowledge is crucial for enabling effective conservation measures and defining the limits of sustainable use. The development and application of omics-based approaches to biodiversity research has helped overcome hurdles, such as allowing the previously hidden community of microbial life to be identified, thereby enabling a holistic view of an entire ecosystem’s biodiversity and functioning. The potential of omics-based approaches for marine ecosystems observation is enormous and their added value to ecosystem monitoring, management, and conservation is widely acknowledged. Despite these encouraging prospects, most omics-based studies are short-termed and typically cover only small spatial scales which therefore fail to include the full spatio-temporal complexity and dynamics of the system. To date, few attempts have been made to establish standardised, coordinated, broad scaled, and long-term omics observation networks. Here we outline the creation of an omics-based marine observation network at the European scale, the European Marine Omics Biodiversity Observation Network (EMO BON). We illustrate how linking multiple existing individual observation efforts increases the observational power in large-scale assessments of status and change in biodiversity in the oceans. Such large-scale observation efforts have the added value of cross-border cooperation, are characterised by shared costs through economies of scale, and produce structured, comparable data. The key components required to compile reference environmental datasets and how these should be linked are major challenges that we address.</jats:p

    The Relevance of Marine Chemical Ecology to Plankton and Ecosystem Function: An Emerging Field

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    Marine chemical ecology comprises the study of the production and interaction of bioactive molecules affecting organism behavior and function. Here we focus on bioactive compounds and interactions associated with phytoplankton, particularly bloom-forming diatoms, prymnesiophytes and dinoflagellates. Planktonic bioactive metabolites are structurally and functionally diverse and some may have multiple simultaneous functions including roles in chemical defense (antipredator, allelopathic and antibacterial compounds), and/or cell-to-cell signaling (e.g., polyunsaturated aldehydes (PUAs) of diatoms). Among inducible chemical defenses in response to grazing, there is high species-specific variability in the effects on grazers, ranging from severe physical incapacitation and/or death to no apparent physiological response, depending on predator susceptibility and detoxification capability. Most bioactive compounds are present in very low concentrations, in both the producing organism and the surrounding aqueous medium. Furthermore, bioactivity may be subject to synergistic interactions with other natural and anthropogenic environmental toxicants. Most, if not all phycotoxins are classic secondary metabolites, but many other bioactive metabolites are simple molecules derived from primary metabolism (e.g., PUAs in diatoms, dimethylsulfoniopropionate (DMSP) in prymnesiophytes). Producing cells do not seem to suffer physiological impact due to their synthesis. Functional genome sequence data and gene expression analysis will provide insights into regulatory and metabolic pathways in producer organisms, as well as identification of mechanisms of action in target organisms. Understanding chemical ecological responses to environmental triggers and chemically-mediated species interactions will help define crucial chemical and molecular processes that help maintain biodiversity and ecosystem functionality
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