scholarly journals DNA-Templated Fluorescent Silver Nanoclusters Inhibit Bacterial Growth While Being Non-Toxic to Mammalian Cells

Molecules ◽  
2021 ◽  
Vol 26 (13) ◽  
pp. 4045
Author(s):  
Lewis Rolband ◽  
Liam Yourston ◽  
Morgan Chandler ◽  
Damian Beasock ◽  
Leyla Danai ◽  
...  
Keyword(s):  
Mammalian Cells ◽  
Antibacterial Properties ◽  
Silver Nanoclusters ◽  
Metal Nanoclusters ◽  
Fluorescent Properties ◽  
Dna Oligonucleotides ◽  
Mammalian Cell Lines ◽  
History Of ◽  
The Stability

Silver has a long history of antibacterial effectiveness. The combination of atomically precise metal nanoclusters with the field of nucleic acid nanotechnology has given rise to DNA-templated silver nanoclusters (DNA-AgNCs) which can be engineered with reproducible and unique fluorescent properties and antibacterial activity. Furthermore, cytosine-rich single-stranded DNA oligonucleotides designed to fold into hairpin structures improve the stability of AgNCs and additionally modulate their antibacterial properties and the quality of observed fluorescent signals. In this work, we characterize the sequence-specific fluorescence and composition of four representative DNA-AgNCs, compare their corresponding antibacterial effectiveness at different pH, and assess cytotoxicity to several mammalian cell lines.

scholarly journals Hg2+ Detection with Rational Design of DNA-Templated Fluorescent Silver Nanoclusters

Processes ◽  
2021 ◽  
Vol 9 (10) ◽  
pp. 1699
Author(s):  
Liam Yourston ◽  
Polikron Dhoqina ◽  
Nolan Marshall ◽  
Rujani Mahmud ◽  
Ethen Kuether ◽  
...  
Keyword(s):  
Optical Properties ◽  
Rational Design ◽  
Visible Spectral Range ◽  
Silver Nanoclusters ◽  
Hairpin Loop ◽  
Fluorescent Properties ◽  
Dna Oligonucleotides ◽  
Loop Sequence ◽  
Detectable Range ◽  
Additional Stability

Atomically precise silver nanoclusters (AgNCs) are small nanostructures consisting of only a few atoms of silver. The combination of AgNCs with cytosine-rich single-stranded oligonucleotides results in DNA-templated silver nanoclusters (DNA-AgNCs). DNA-AgNCs are highly luminescent and can be engineered with reproducible and unique fluorescent properties. Furthermore, using nucleic acids as templates for the synthesis of AgNCs provides additional practical benefits by expanding optical activity beyond the visible spectral range and creating the possibility for color tunability. In this study, we explore DNA oligonucleotides designed to fold into hairpin-loop (HL) structures which modulate optical properties of AgNCs based on the size of the loop containing different number of cytosines (HL-CN). Depending on the size of the loop, AgNCs can be manufactured to have either single or multiple emissive states. Such hairpin-loop structures provide an additional stability for AgNCs and further control over the base composition of the loop, allowing for the rational design of AgNCs’ optical properties. We demonstrate the potential of AgNCs in detecting Hg2+ by utilizing the HL-C13 design and its variants HL-T2C11, HL-T4C9, and HL-T6C7. The replacement of cytosines with thymines in the loop was intended to serve as an additional sink for mercury ions extending the detectable range of Hg2+. While AgNC@HL-T0C13 exhibits an interpretable quenching curve, AgNC@HL-T6C7 provides the largest detectable range of Hg2+. The results presented herein suggest that it is possible to use a rational design of DNA-AgNCs based on the composition of loop sequence in HL structures for creating biosensors to detect heavy metals, particularly Hg2+.

IoT-Enabled Non-Contact-Based Infrared Thermometer for Temperature Recording of a Person

2021 ◽  
pp. 195-203
Author(s):  
Swapna B.
Keyword(s):  
Real Time ◽  
Web Application ◽  
Temperature Data ◽  
Monitoring Systems ◽  
Laboratory Environment ◽  
Environment Temperature ◽  
History Of ◽  
The Stability ◽  
Indoor Conditions

Laboratories are essential facilities provided in professional institutes for scientific and technological work. The lab must ensure their accuracy to regulatory requirements and maintain their data records so that the laboratory environment can be monitored properly. The laboratory environment temperature (LET) is monitored to ensure proper regulation and maintenance of indoor conditions and also to correlate the collected samples with these conditions. The LET data collection must be stored to influence the quality of the results and to ensure the stability of the laboratory environment. Hence, an IoT solution is presented to supervise real-time temperature and is known as iRT. This method helps to monitor ambient object supervision in real time. It is composed of a hardware prototype to collect the temperature data and to use web application to provide the history of temperature evolution. The result gained from the study is promising, and it provides a significant contribution to IoT-based temperature monitoring systems.

scholarly journals DRY MIXTURES AND MIXING EQUIPMENT FOR THEIR PRODUCTION

2021 ◽  
Vol 5 (12) ◽  
pp. 145-150
Author(s):  
Y. Fadin ◽  
O. Shemetova
Keyword(s):  
Building Materials ◽  
Raw Materials ◽  
Mixing Process ◽  
Chemical Additives ◽  
High Quality ◽  
Main Indicator ◽  
History Of ◽  
The Creation ◽  
The Stability

Today’s economic situation creates conditions for revising the existing base of materials and raw materials in construction, as well as for transforming and using it in the future. One of the ways to achieve this goal is the creation of new types of building materials, more effective and low in the price category compared to the classic ones. Dry building mixtures belongs to such materials. The high quality of dry building mixes is guaranteed by the stability of their composition and the properties of the ingredients used. Saving time when using high-quality dry building mixes will allow to get an irreproachable end result. A necessary component in the manufacture of dry building mixtures is the mixing process, which includes the preparation of raw materials, dosing and the distribution of chemical additives. The main indicator of the quality of the finished product in the production of dry mixes is its uniformity. Therefore, special attention is paid to the mixing section in the production line. The variety of bulk materials and their properties contributes to the creation of various types of mixers for high-quality mixing of components. The article discusses the history of the emergence of dry building mixes and mixing equipment for production.

scholarly journals Dynamic interactions and intracellular fate of label-free GO within mammalian cells: role of lateral sheet size

2019 ◽  
Author(s):  
Yingxian Chen ◽  
Livia Elena Crică ◽  
Vinicio Rosano ◽  
Adrián Esteban Arranz ◽  
David Spiller ◽  
...  
Keyword(s):  
Cell Lines ◽  
Mammalian Cells ◽  
Analytical Techniques ◽  
Transport Systems ◽  
Dependent Manner ◽  
Label Free ◽  
Fluorescent Properties ◽  
Uptake Mechanism ◽  
Mammalian Cell Lines ◽  
Intracellular Fate

AbstractGraphene oxide (GO) holds great potential for biomedical applications, however fundamental understanding of the way it interacts with biological systems is still lacking even though it is a prerequisite for successful clinical translation. In this study, we exploited intrinsic fluorescent properties of GO to establish the relationship between lateral dimensions of the material, its cellular uptake mechanism and intracellular fate. Label-free GO with distinct lateral dimensions, small (s-GO) and ultra-small (us-GO), was synthesized and thoroughly characterised both in water and in biologically relevant cell culture medium. Interactions of the material with a range of non-phagocytic mammalian cell lines (BEAS-2B, NIH/3T3, HaCaT, 293T) were studied using a combination of complementary analytical techniques (confocal microscopy, flow cytometry and TEM). The uptake mechanism was interrogated using a range of pharmaceutical inhibitors for main endocytic pathways (ethyl-isopropyl amiloride, monodansylcadaverine, chlorpromazine, genistein, cytochalasin D, latrunculin A, dynasore and sodium azide), and validated using negatively charged polystyrene beads with different diameters (0.1 and 1 μm). Regardless of lateral dimension, both types of GO were found to interact with the plasma membrane and to be efficiently taken up by a panel of cell lines in a time- and dose-dependent manner. s-GO was internalised mainly via macropinocytosis while us-GO used mainly clathrin- and caveolae-mediated endocytosis. Lastly, we show that both s-GO and us-GO terminate in lysosomal compartments for up to 48 h. Our results aim to offer significant insight into the mechanism of interaction of GO with non-phagocytic cell lines that can be exploited for the design of biomedically applicable 2D transport systems.

Financial Globalization as a Barrier to Democratic Consolidation: a North-South Model with Public Goods

2020 ◽  
Vol 0 (0) ◽  
Author(s):  
Gabriel Porcile
Keyword(s):  
Public Goods ◽  
Economic History ◽  
Capital Mobility ◽  
Democratic Consolidation ◽  
Empirical Literature ◽  
Financial Globalization ◽  
History Of ◽  
The Stability ◽  
The Impact

AbstractThis paper modifies the Acemoglu–Robinson model of the economic basis of democracy to discuss the impact of the international regime regulating capital flows on the consolidation and quality of democracy. Two regimes of capital mobility are considered, Bretton Woods and Rodrik’s hyperglobalization, in an international economy formed by an advanced North and a developing South. The model shows that hyperglobalization compromises the stability of democracy in the South by limiting the ability of the citizens to tax the elite and provide public goods which are critical for technical change and income distribution. At variance with the mainstream results, it is argued that financial globalization is a barrier to democratic consolidation. The model is consistent with key findings of the empirical literature on globalization and democracy, as well as with evidence from the economic history of Latin America.

Criteria for evaluation of the coordinate measurements quality of parts geometric parameters at pilot-experimental production

2019 ◽  
pp. 3-8
Author(s):  
N.Yu. Bobrovskaya ◽  
M.F. Danilov
Keyword(s):  
Quality Indicators ◽  
Quality Management System ◽  
Technical Specification ◽  
Experimental Production ◽  
Technological Heredity ◽  
Coordinate Measurements ◽  
Reasonable Choice ◽  
The Stability ◽  
Geometric Elements

The criteria of the coordinate measurements quality at pilot-experimental production based on contemporary methods of quality management system and traditional methods of the measurements quality in Metrology are considered. As an additional criterion for quality of measurements, their duration is proposed. Analyzing the problem of assessing the quality of measurements, the authors pay particular attention to the role of technological heredity in the analysis of the sources of uncertainty of coordinate measurements, including not only the process of manufacturing the part, but all stages of the development of design and technological documentation. Along with such criteria as the degree of confidence in the results of measurements; the accuracy, convergence, reproducibility and speed of the results must take into account the correctness of technical specification, and such characteristics of the shape of the geometric elements to be controlled, such as flatness, roundness, cylindrical. It is noted that one of the main methods to reduce the uncertainty of coordinate measurements is to reduce the uncertainty in the initial data and measurement conditions, as well as to increase the stability of the tasks due to the reasonable choice of the basic geometric elements (measuring bases) of the part. A prerequisite for obtaining reliable quality indicators is a quantitative assessment of the conditions and organization of the measurement process. To plan and normalize the time of measurements, the authors propose to use analytical formulas, on the basis of which it is possible to perform quantitative analysis and optimization of quality indicators, including the speed of measurements.

Probiotics in gastroenterology – from a different angle

2013 ◽  
Vol 154 (8) ◽  
pp. 294-304 ◽  
Author(s):  
György Miklós Buzás
Keyword(s):  
Side Effects ◽  
Beneficial Effect ◽  
Analytical Data ◽  
Well Being ◽  
Gastrointestinal Diseases ◽  
Convincing Evidence ◽  
Probiotic Treatment ◽  
History Of ◽  
Irritable Bowel

After a short overview of the history of probiotics, the author presents the development of human intestinal microflora based on the newest genetic data and the microbiological features of main probiotics. The indications of probiotic administration have been defined and extended in recent years. The author reviews significant results of probiotic treatment in some gastrointestinal diseases based on meta-analytical data. Probiotics are useful in preventing and treating diarrhoea caused by antibiotics and Clostridium difficile caused diarrhoea. In the treatment of Helicobacter pylori infection, preparations containing certain Lactobacillus,Bifidobacterium strains or Saccaromyces boulardii could enhance by 5–10% the rate of successful eradication and reduce the incidence and severity of the side effects. Some symptoms of irritable bowel syndrome and thus the quality of life can be improved by probiotics. Their beneficial effect in ulcerative colitis was proven, while in Crohn’s disease has not yet been defined. The use of probiotics is not included in guidelines, with the exception of the Maastricht IV/Florence consensus. For each disease it is advisable to use probiotics containing strains only with proven beneficial effect. The efficiency of preparations containing mixed strains has not yet been properly investigated. The author reviews the rare but potentially serious side effects of probiotics. In Hungary, there are many probiotic preparations available which can be purchased in pharmacies without prescription: their use is more empirical than evidence-based. The European Food Safety Authority has recently rejected claims for probiotics to be classed as medicines given the lack of convincing evidence on the effects of probiotics on human health and well-being. Clearly, further research is needed to collect evidence which could be incorporated into the international guidelines. Orv. Hetil., 2013, 154, 294–304.

EXPLORING HEALTHCARE ARCHITECTURE THROUGH THE MEDIUM OF FILM: Motives and Techniques

2014 ◽  
Vol 8 (1) ◽  
pp. 29
Author(s):  
Stephen Verderber
Keyword(s):  
Real World ◽  
The Real ◽  
Healthcare Settings ◽  
Interdisciplinary Field ◽  
Body Of Knowledge ◽  
Behavior Setting ◽  
Physical Environments ◽  
Scant Attention ◽  
History Of

The interdisciplinary field of person-environment relations has, from its origins, addressed the transactional relationship between human behavior and the built environment. This body of knowledge has been based upon qualitative and quantitative assessment of phenomena in the “real world.” This knowledge base has been instrumental in advancing the quality of real, physical environments globally at various scales of inquiry and with myriad user/client constituencies. By contrast, scant attention has been devoted to using simulation as a means to examine and represent person-environment transactions and how what is learned can be applied. The present discussion posits that press-competency theory, with related aspects drawn from functionalist-evolutionary theory, can together function to help us learn of how the medium of film can yield further insights to person-environment (P-E) transactions in the real world. Sampling, combined with extemporary behavior setting analysis, provide the basis for this analysis of healthcare settings as expressed throughout the history of cinema. This method can be of significant aid in examining P-E transactions across diverse historical periods, building types and places, healthcare and otherwise, otherwise logistically, geographically, or temporally unattainable in real time and space.

Statistical Management of Food Production Processes

2020 ◽  
pp. 30-35
Author(s):  
N.A. Jurk ◽  
Keyword(s):  
Production Process ◽  
Control Chart ◽  
Food Production ◽  
Time Interval ◽  
Bakery Products ◽  
Shewhart Control ◽  
Manufactured Products ◽  
Mnemonic Technique ◽  
The Stability

The article presents scientific research in the field of statistical controllability of the food production process using the example of bakery products for a certain time interval using statistical methods of quality management. During quality control of finished products, defects in bakery products were identified, while the initial data were recorded in the developed form of a checklist for registering defects. It has been established that the most common defect is packaging leakage. For the subsequent statistical assessment of the stability of the production process and further analysis of the causes of the identified defect, a Shewhart control chart (p-card by an alternative feature) was used, which allows you to control the quality of manufactured products by the number of defects detected. Analyzing the control chart, it was concluded that studied process is conditionally stable, and the emerging defects are random. At the last stage of the research, the Ishikawa causal diagram was used, developed using the 6M mnemonic technique, in order to identify the most significant causes that affect the occurrence of the considered defect in bakery products. A more detailed study will allow the enterprise to produce food products that meet the established requirements.

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