758 results match your criteria: "Riga Technical University.[Affiliation]"

In this research, we explore the synthesis of and characterize α-aminophosphonates derived from anthraquinone and benzanthrone, focusing on their fluorescence properties and potential applications in confocal laser scanning microscopy (CLSM). The synthesized compounds exhibit notable solvatochromic behavior, emitting fluorescence from green to red across various solvents. Spectroscopic analysis, including H-, C-, and P-NMR, FTIR, and mass spectrometry, confirms the chemical structures.

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Apatite/Chitosan Composites Formed by Cold Sintering for Drug Delivery and Bone Tissue Engineering Applications.

Nanomaterials (Basel)

February 2024

Institute of Biomaterials and Bioengineering, Faculty of Natural Sciences and Technology, Riga Technical University, Pulka St. 3, LV-1007 Riga, Latvia.

In the biomedical field, nanocrystalline hydroxyapatite is still one of the most attractive candidates as a bone substitute material due to its analogies with native bone mineral features regarding chemical composition, bioactivity and osteoconductivity. Ion substitution and low crystallinity are also fundamental characteristics of bone apatite, making it metastable, bioresorbable and reactive. In the present work, biomimetic apatite and apatite/chitosan composites were produced by dissolution-precipitation synthesis, using mussel shells as a calcium biogenic source.

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Terminology of e-Oral Health: Consensus Report of the IADR's e-Oral Health Network Terminology Task Force.

BMC Oral Health

February 2024

Department of Oral Healthcare; Health, Sports and Welfare, InHolland University of Applied Sciences, Gustav Mahlerlaan 3004, Amsterdam, Noord-Holland, 1081LA, The Netherlands.

Objective: Authors reported multiple definitions of e-oral health and related terms, and used several definitions interchangeably, like mhealth, teledentistry, teleoral medicine and telehealth. The International Association of Dental Research e-Oral Health Network (e-OHN) aimed to establish a consensus on terminology related to digital technologies used in oral healthcare.

Method: The Crowdsourcing Delphi method used in this study comprised of four main stages.

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Dataset on Trombe wall application in a factory building.

Data Brief

April 2024

Department of Electrical, Electronic and Computer Engineering, Faculty of Engineering and the Built Environment, Cape Peninsula University of Technology, Cape Town 7535, South Africa.

An experimental passive solar thermal transmission wall (also known as Trombe wall) prototype was installed on a factory building wall in Kalnciems, Latvia to carry out temperature measurements at different representative locations in order to evaluate Trombe wall's potential to be used as a secondary space heating source. The average winter temperature in Kalnciems is 0.7 °C which stipulates the need for space heating (6-7 months a year).

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Wastewater-based epidemiology (WBE) was applied to evaluate the consumption trends of pharmaceuticals (i.e., antibiotics, non-steroidal anti-inflammatory drugs, antiepileptics, antihypertensives, and others), as well as recreational drugs (caffeine, alcohol, and nicotine), in Latvia from December 2020 to July 2023.

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The first search for scalar leptoquarks produced in τ-lepton-quark collisions is presented. It is based on a set of proton-proton collision data recorded with the CMS detector at the LHC at a center-of-mass energy of 13 TeV corresponding to an integrated luminosity of 138  fb^{-1}. The reconstructed final state consists of a jet, significant missing transverse momentum, and a τ lepton reconstructed through its hadronic or leptonic decays.

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Doxorubicin loaded octacalcium phosphate particles as controlled release drug delivery systems: Physico-chemical characterization, in vitro drug release and evaluation of cell death pathway.

Int J Pharm

March 2024

Institute of Biomaterials and Bioengineering, Faculty of Natural Sciences and Technology, Riga Technical University, Pulka 3, Riga LV-1007, Latvia; Baltic Biomaterials Centre of Excellence, Headquarters at Riga Technical University, Riga, Latvia. Electronic address:

Mastering new and efficient ways to obtain successful drug delivery systems (DDS) with controlled release became a paramount quest in the scientific community. Increase of malignant bone tumors and the necessity to optimize an approach of localized drug delivery require research to be even more intensified. Octacalcium phosphate (OCP), with a number of advantages over current counterparts is extensively used in bone engineering.

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Extracellular vesicles (EVs) hold immense potential for various biomedical applications, including diagnostics, drug delivery, and regenerative medicine. Nevertheless, the current methodologies for isolating EVs present significant challenges, such as complexity, time consumption, and the need for bulky equipment, which hinders their clinical translation. To address these limitations, we aimed to develop an innovative microfluidic system based on cyclic olefin copolymer-off-stoichiometry thiol-ene (COC-OSTE) for the efficient isolation of EVs from large-volume samples in a continuous manner.

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Two pathways toward 6-selanyl-2-triazolylpurine derivatives were designed. The first method involved the synthesis of 2-chloro-6-selanylpurine derivatives, further SAr reaction with NaN, and following CuAAC using different alkynes. The second method was based on the synthesis of 2,6-bistriazolylpurine derivatives as starting materials followed by SAr reaction with commercial or in situ generated selenols as nucleophiles.

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Motivated by the requirements of performance stability in environments of variable humidity, the focus of this study is on the effects and role of humidity-induced water molecules and ions in the contact electrification (CE) mechanisms of triboelectric materials. In particular, the compatibility of direct charge transfer-based CE and other generally known or proposed water molecules or OH/HO ion-facilitated CE mechanisms was assessed for a set of high-performance polymeric materials and functionalization molecules. The first set of test mechanisms included OH/HO ion adsorption at the low-humidity limit.

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The human body emits a multitude of volatile organic compounds (VOCs) via tissues and various bodily fluids or exhaled breath. These compounds collectively create a distinctive chemical profile, which can potentially be employed to identify changes in human metabolism associated with colorectal cancer (CRC) and, consequently, facilitate the diagnosis of this disease. The main goal of this study was to investigate and characterize the VOCs' chemical patterns associated with the breath of CRC patients and controls and identify potential expiratory markers of this disease.

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Background: Current obstructive sleep apnea treatment relies on manual PAP titration, but it has limitations. Complex interactions during titration and variations in SpO data accuracy pose challenges. Patients with co-occurring chronic hypercapnia may require precise oxygen titration.

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A search for dark matter in events with a displaced nonresonant muon pair and missing transverse momentum is presented. The analysis is performed using an integrated luminosity of 138  fb^{-1} of proton-proton (pp) collision data at a center-of-mass energy of 13 TeV produced by the LHC in 2016-2018. No significant excess over the predicted backgrounds is observed.

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Osteochondral defect repair with a collagen/collagen-magnesium-hydroxyapatite (Col/Col-Mg-HAp) scaffold has demonstrated good clinical results. However, subchondral bone repair remained suboptimal, potentially leading to damage to the regenerated overlying neocartilage. This study aimed to improve the bone repair potential of this scaffold by incorporating newly developed strontium (Sr) ion enriched amorphous calcium phosphate (Sr-ACP) granules (100-150 μm).

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Small organic molecules containing amorphous calcium phosphate: synthesis, characterization and transformation.

Front Bioeng Biotechnol

January 2024

Rudolfs Cimdins Riga Biomaterials Innovations and Development Centre of RTU, Institute of General Chemical Engineering, Faculty of Materials Science and Applied Chemistry, Riga Technical University, Riga, Latvia.

As the primary solid phase, amorphous calcium phosphate (ACP) is a pivotal precursor in cellular biomineralization. The intrinsic interplay between ACP and Howard factor underscores the significance of understanding their association for advancing biomimetic ACP development. While organic compounds play established roles in biomineralization, this study presents the synthesis of ACP with naturally occurring organic compounds (ascorbate, glutamate, and itaconate) ubiquitously found in mitochondria and vital for bone remodeling and healing.

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Fucoidan/chitosan hydrogels as carrier for sustained delivery of platelet-rich fibrin containing bioactive molecules.

Int J Biol Macromol

March 2024

Institute of Biomaterials and Bioengineering, Faculty of Natural Science and Technology, Riga Technical University, LV-1048 Riga, Latvia; Baltic Biomaterials Centre of Excellence, Headquarters at Riga Technical University, LV-1048 Riga, Latvia. Electronic address:

Platelet-rich fibrin (PRF), derived from human blood, rich in wound healing components, has drawbacks in direct injections, such as rapid matrix degradation and growth factor release. Marine polysaccharides, mimicking the human extracellular matrix, show promising potential in tissue engineering. In this study, we impregnated the self-assembled fucoidan/chitosan (FU_CS) hydrogels with PRF obtaining PRF/FU_CS hydrogels.

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The first evidence for the Higgs boson decay to a Z boson and a photon is presented, with a statistical significance of 3.4 standard deviations. The result is derived from a combined analysis of the searches performed by the ATLAS and CMS Collaborations with proton-proton collision datasets collected at the CERN Large Hadron Collider (LHC) from 2015 to 2018.

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Toward the Assembly of 2D Tunable Crystal Patterns of Spherical Colloids on a Wafer-Scale.

ACS Appl Mater Interfaces

March 2024

Mesoscale Chemical Systems, MESA+ Institute, University of Twente, P.O. Box 217, 7500AE Enschede, The Netherlands.

Entering an era of miniaturization prompted scientists to explore strategies to assemble colloidal crystals for numerous applications, including photonics. However, wet methods are intrinsically less versatile than dry methods, whereas the manual rubbing method of dry powders has been demonstrated only on sticky elastomeric layers, hindering particle transfer in printing applications and applicability in analytical screening. To address this clear impetus of broad applicability, we explore here the assembly on nonelastomeric, rigid substrates by utilizing the manual rubbing method to rapidly (≈20 s) attain monolayers comprising hexagonal closely packed (HCP) crystals of monodisperse dry powder spherical particles with a diameter ranging from 500 nm to 10 μm using a PDMS stamp.

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The demand for eco-friendly packaging materials has urged researchers to look for alternatives to petroleum-based polymers. In this regard, paper-based products have turned out to be a promising choice; however, their weak resistance to water has limited their application. The use of various additives to enhance paper's moisture resistance is a common practice.

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Study of Lightweight Ceramic Matrix-Less Syntactic Foam Composed of Cenosphere Using Spark Plasma Sintering.

Materials (Basel)

January 2024

Laboratory of Ecological Solutions and Sustainable Development of Materials, Institute of General Chemical Engineering, Faculty of Materials Science and Applied Chemistry, Riga Technical University, Paula Valdena Street 3/7, LV-1048 Riga, Latvia.

The current investigation presents porous ceramic materials prepared with cenospheres (CS) by using spark plasma sintering. The impact of sintering temperature, mould diameter (20, 30 and 50 mm) and cenosphere size on the properties of the sintered material was investigated. Shrinkage of the samples during sintering started at 900 °C.

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The integration of artificial intelligence (AI), particularly through machine learning (ML) and deep learning (DL) algorithms, marks a transformative progression in medical imaging diagnostics. This technical note elucidates a novel methodology for semantic segmentation of the vertebral column in CT scans, exemplified by a dataset of 250 patients from Riga East Clinical University Hospital. Our approach centers on the accurate identification and labeling of individual vertebrae, ranging from C1 to the sacrum-coccyx complex.

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Fusion and classification algorithm of octacalcium phosphate production based on XRD and FTIR data.

Sci Rep

January 2024

Center for Translational Research on Autoimmune and Allergic Diseases-CAAD, Department of Health Sciences, Università del Piemonte Orientale UPO, 28100, Novara, Italy.

The present manuscript tested an automated analysis sequence to provide a decision support system to track the OCP synthesis from [Formula: see text]-TCP over time. Initially, the XRD and FTIR signals from a hundredfold scaled-up hydrolysis of OCP from [Formula: see text]-TCP were fused and modeled by the curve fitting based on the significantly established maxima from the literature and nine features extracted from the fitted shapes. Afterward, the analysis sequence enclosed the machine learning techniques for feature ranking, spatial filtering, and dimensionality reduction to support the automatic recognition of the synthesis stages.

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Immunomodulation by xylan and carrageenan-type polysaccharides from red seaweeds: Anti-inflammatory, wound healing, cytoprotective, and anticoagulant activities.

Int J Biol Macromol

March 2024

Department of Cellular and Molecular Medicine, Faculty of Medicine, University of Ottawa, Ontario K1H 8M5, Canada; Department of Innovation in Medical Education, Faculty of Medicine, University of Ottawa, Ontario K1H 8M5, Canada. Electronic address:

The immunomodulatory properties of the polysaccharides (carrageenan, xylan) from Chondrus crispus (CC), Ahnfeltiopsis devoniensis (AD), Sarcodiotheca gaudichaudii (SG) and Palmaria palmata (PP) algal species were studied. Using RAW264.7 macrophages, we investigated the proliferation and migration capacity of different extracts along with their immunomodulatory activities, including nitric oxide (NO) production, phagocytosis, and secretion of pro-inflammatory cytokines.

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Article Synopsis
  • - The study investigates the strange quark content of protons by measuring the production cross section of W bosons and charm quarks in proton-proton collisions at 13 TeV, using data from the CMS detector at the LHC.
  • - W bosons are identified through their decays into leptons (electrons or muons) and neutrinos, while charm quarks are tagged by detecting muons or secondary vertices in jets.
  • - The measurements, which reach a precision of 1%, include both inclusive and differential analyses based on the transverse momentum and pseudorapidity of the leptons, and the results are compared with advanced theoretical predictions in quantum chromodynamics.
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The measurement of Z boson production is presented as a method to determine the integrated luminosity of CMS data sets. The analysis uses proton-proton collision data, recorded by the CMS experiment at the CERN LHC in 2017 at a center-of-mass energy of 13. Events with Z bosons decaying into a pair of muons are selected.

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