ENERGY DISPERSION X-RAY FLUORESCENCE ANALYSIS FOR ENVIRONMENT PROTECTION

Environmental monitoring is aimed mostly at pollution levels change tendency estimation and high sensitive analysis methods are applied for this purpose. X-Ray fluorescence analysis (RFA) allows getting information of metal content in ten or hundred seconds. The analyzers with Si(Li) detectors were used for measurements. Our report deals with some examples which are given as new RFA methods (with secondary target) application in the laboratory and field conditions

PROJECT MODELLING TOOLBOX IN HIGHER EDUCATION: HEXAGONAL CANVAS IN PROJECT BASED LEARNING

Inclusion of project modelling tools into higher education is based on expectations of industry about young professionals with applicable, rich skillset. Business or project model canvas is one of the most widely used frameworks in contrary to traditional planning tools. Pedagogically - project model canvas is a teaching goal and method simultaneously. Those aspects widen possibilities to integrate the tool in various study courses and levels. The aim of the research is to explore and evaluate functional and cognitive impacts of Hex-canvas use in project-based learning in higher education. This tool is represented in a form of template of 11 fundamental elements which describe a specific aspect of a project. The research is based on experiences gathered in Vidzeme University of Applied Sciences, Latvia. Data used in this research has been comprised of structured interviews of doctoral level students (n=8) who used Hex-canvas in summer school and from bachelor and master level students (n=16) of “I Living Labs” study course (year 2022). Results reveal high applicability in structuring of the projects, defining aims and activities for implementation, it gives overall perspective of project, however there must be clear instructions by teachers, as well the consistency of usage is recommended.

Promocijas darbs

Darbā veikti nesimetrisko λ3-jodānu un dažādu skābekļa un slāpekļa nukleofīlu mijiedarbības pētījumi. Balstoties uz iegūtajiem rezultātiem, sekmīgi izstrādātas viena reaktora secīgu daudzstadiju reakciju metodes C-H saites aktivēšanai/funkcionalizēšanai. Metožu pielietojums ir parādīts uz plaša substrātu klāsta. C-H Saišu funkcionalizēšanas pieeja balstās uz in situ ģenerētu nesimetrisku λ3-jodānu un dažādu nukleofīlu (acetātu, fenolātu, azīdu un plaša alifātisku un aromātisko amīnu) klāsta reakciju pārejas metālu (Pd, Cu) katalīzes apstākļos. Izstrādātas metodoloģijas pielietojums potenciālo zāļvielu “vēlīnai modificēšanai” parādīts antibakteriālā līdzekļa linezolīda sintēzē.Reactivity of unsymmetrical λ3-iodanes with various O- and N-nucleophiles was investigated and new sequential one-pot multi-step C-H bond functionalization approach has been developed. The new methodology is based on a regioselective reaction of the in situ generated unsymmetrical λ3-iodanes with a range of nucleophiles (acetates, phenolates, azides and various aliphatic and aromatic amines) in the presence of transition metal (Pd, Cu) catalysts. Suitability of the developed methodology for late-stage modification of the potential drug molecules was demonstrated in synthesis of antibacterial linezolid

The influence of the design of removable dentures on patient's voice quality

The main condition for speech intelligibility is the specific anatomical characteristics of the human speech apparatus and harmonious work of all organs in the human vocal apparatus. The voice quality is characterized by speech intelligibility (relationship between the voice pitch, volume, timbre and speech speed). Improper functional quality (related to retention,support, stability), inappropriate design of the prosthetic base and disposition of artificial teeth are the basic reasons for dyslalia - impairment of utterance with abnormality of external speech organs. In the case of dyslalia a patient may suffer from a defective utterance of separate phonemes. When designing removable dental prostheses, it is important to evaluate the disposition of the artifical teeth (taking into account phonetic pronunciation), make a phonetically beneficial construction of the base of the dentures and restore the lost alveolar bone with the basis of removable prostheses. The aim of this study was to review literature on voice quality and the way it can be affected after the insertion of removable dental prostheses and to research the literature describing the ways how voice quality can be improved. The literature reviewed in the paper was retrieved from Science Direct, PubMed, MD Consult, Cochrane Libary databases and dates back to the period from 1990 to 2012.publishersversionPeer reviewe

A Conceptual Model for Deploying E-Service in SMEs through Capability Building: A Comparative Case Study

This paper proposes a conceptual implementation model for small and medium enterprises (SMEs) to follow as part of their digital transformation. The conceptual model can be translated into a practical step-by-step guide for SMEs to apply during their digital transformation. The model is based on gradually developing industrial capabilities that can influence production processes performance. We employed a comparative case study approach to capture the lessons learned by SMEs in their journey to develop and implement a production digitalization system for deviation management and performance improvement. The model was validated in the cases of study capturing the actual SMEs’ needs. Managerial capabilities of production processes such as monitoring and control demonstrate to influence the performance positively. The proposed model aims for a full digital transformation by following a gradual approach to being resource-efficient and integrating their business needs. This paper is an extension of work originally presented in APMS 2020, IFIP AICT 592

Identifying the Microbiome of the Adenoid Surface of Children Suffering from Otitis Media with Effusion and Children without Middle Ear Effusion Using 16S rRNA Genetic Sequencing

Funding Information: Research funded by “Centrālā Laboratorija”, further information upon request. During the manuscript preparation and review process, Rihards Saksis was supported by the project “Strengthening of the capacity of doctoral studies at the University of Latvia within the framework of the new doctoral model”, identification No.8.2.2.0/20/I/006. Publisher Copyright: © 2023 by the authors.Background: The upper respiratory tract harbors diverse communities of commensal, symbiotic, and pathogenic organisms, originating from both the oral and nasopharyngeal microbiota. Among the primary sites of microbial colonization in the upper airways are the adenoids. Alterations in the adenoid microbiota have been implicated in the development of various conditions, including secretory otitis media. Aim: This study aims to employ 16S rRNA genetic sequencing to identify the most common bacteria present on the surface of adenoids in children with otitis media with effusion and compare them with children without pathologies in the tympanic cavity. Additionally, we seek to determine and compare the bacterial diversity in these two study groups. Materials and Methods: A total of nineteen samples from the adenoid surfaces were collected, comprising two groups: thirteen samples from children without middle ear effusion and six samples from children with secretory otitis media. The libraries of the V3–V4 hypervariable region of the bacterial 16S rRNA gene was made and sequenced using MiSeq platform. Results: The most prevalent phyla observed in both groups were Proteobacteria, Firmicutes, and Bacteroidetes. The most common bacterial genera identified in both groups were Haemophilus, Streptococcus, Moraxella, Fusobacterium, and Bordetella, with Fusobacterium and Moraxella being more prevalent in the groups that had no middle ear effusion, while Haemophulus and Streptococcus were more prevalent in the otitis media with effusion group, although not in a statistically significant way. Statistical analysis shows a trend towards bacterial composition and beta diversity being similar between the study groups; however, due to the limited sample size and unevenness between groups, we should approach this data with caution. Conclusion: The lack of prolific difference in bacterial composition between the study groups suggests that the role of the adenoid microbiome in the development of otitis media with effusion may be less significant.Peer reviewe

An Overview of Adenoid Microbiome Using 16S rRNA Gene Sequencing-Based Metagenomic Analysis

Background and Objectives: the upper respiratory tract harbors the highest bacterial density in the whole respiratory system. Adenoids, which are located in the nasopharynx, are a major site of bacterial colonies in the upper airways. Our goal was to use culture-independent molecular techniques to identify the breadth of bacterial diversity in the adenoid vegetations of children suffering from chronic rhinosinusitis and obstructive sleep apnea. Materials and methods: in total, 21 adenoid samples were investigated using amplification and sequencing of the V3-V4 hypervariable region of the bacterial 16S rRNA gene. Results: among the most common bacterial species found were Veillonella atypica, Fusobactrium nucelatum, Shaalia odontolytica, and Moraxella catarrhalis. Veillonella atypica and Fusbacterium nucelatum dominated the microbiome in all 21 samples, attributing to more than 60% of all detected genetic material. Conclusions: since both Veillonella atypica and Fusobacterium nucleatum are, predominantly, oral cavity and dental microorganisms, our findings may suggest oral microbiome migration deeper into the oropharynx and nasopharynx where these bacteria colonize adenoid vegetations.publishersversionPeer reviewe

Electrochemistry and Reactivity of Chelation‐stabilized Hypervalent Bromine(III) Compounds

Hypervalent bromine(III) reagents possess a higher electrophilicity and a stronger oxidizing power compared to their iodine(III) counterparts. Despite the superior reactivity, bromine(III) reagents have a reputation of hard‐to‐control and difficult‐to‐synthesize compounds. This is partly due to their low stability, and partly because their synthesis typically relies on the use of the toxic and highly reactive BrF3 as a precursor. Recently, we proposed chelation‐stabilized hypervalent bromine(III) compounds as a possible solution to both problems. First, they can be conveniently prepared by electro‐oxidation of the corresponding bromoarenes. Second, the chelation endows bromine(III) species with increased stability while retaining sufficient reactivity, comparable to that of iodine(III) counterparts. Finally, their intrinsic reactivity can be unlocked in the presence of acids. Herein, an in‐depth mechanistic study of both the electrochemical generation and the reactivity of the bromine(III) compounds is disclosed, with implications for known applications and future developments in the field.Deutsche Forschungsgemeinschaft http://dx.doi.org/10.13039/501100001659European Regional Development Fund http://dx.doi.org/10.13039/501100008530HORIZON EUROPE European Research Council http://dx.doi.org/10.13039/100019180Estonian Research Competency Council http://dx.doi.org/10.13039/501100005189Peer Reviewe