scholarly journals Hypoxia-on-a-chip

2016 ◽  
Vol 2 (1) ◽  
pp. 71-75 ◽  
Author(s):  
Mathias Busek ◽  
Stefan Grünzner ◽  
Tobias Steege ◽  
Udo Klotzbach ◽  
Frank Sonntag
Keyword(s):  
Oxygen Transfer ◽  
Chemical Resistance ◽  
Cell Cultivation ◽  
Active Components ◽  
Pure Nitrogen ◽  
Micro Pump ◽  
Before And After ◽  
Process Gases ◽  
Fluorescence Lifetime Detection ◽  
Sufficient Oxygen

AbstractIn this work a microfluidic cell cultivation device for perfused hypoxia assays as well as a suitable controlling unit are presented. The device features active components like pumps for fluid actuation and valves for fluid direction as well as an oxygenator element to ensure a sufficient oxygen transfer. It consists of several individually structured layers which can be tailored specifically to the intended purpose. Because of its clearness, its mechanical strength and chemical resistance as well as its well-known biocompatibility polycarbonate was chosen to form the fluidic layers by thermal diffusion bonding. Several oxygen sensing spots are integrated into the device and monitored with fluorescence lifetime detection. Furthermore an oxygen regulator module is implemented into the controlling unit which is able to mix different process gases to achieve a controlled oxygenation. First experiments show that oxygenation/deoxygenation of the system is completed within several minutes when pure nitrogen or air is applied to the oxygenator. Lastly the oxygen input by the pneumatically driven micro pump was quantified by measuring the oxygen content before and after the oxygenator.

scholarly journals Drug Story Theater: A Mixed-Methods Study of a Peer-to-Peer Approach to Substance Abuse Education

2021 ◽  
Vol 8 (4) ◽  
Author(s):  
joseph shrand ◽  
madeline digiovanni ◽  
dana lee ◽  
anita kishnore ◽  
andres martin
Keyword(s):  
Substance Use ◽  
High School Students ◽  
Risk Perceptions ◽  
Peer To Peer ◽  
Active Components ◽  
School Students ◽  
Test Range ◽  
Peer Intervention ◽  
Before And After ◽  
Group Interviews

Objective: Drug Story Theater (DST) is a peer-to-peer intervention that engages teenagers in the early stages of their recovery to develop shows about the seduction of, addiction to, and recovery from drugs and alcohol. Methods: We analyzed anonymous surveys completed by students before and after attending a DST performance, and transcripts of focus group interviews conducted with (1) program developers, (2) stakeholders, (3) performers, and (4) audience members. Results: Students (N = 871) from 5 schools attended one of 2 DST performances. Participants demonstrated increased knowledge on 5 fact-based questions (mean improvement range, 19%- 35%; p < .001 for all), and favorable changes on 10 items addressing perceptions regarding substance use risk (paired t test range, 3.9-9.4; p < .001 for all). Through iterative thematic analysis we developed an alliterative “7P” model spanning 2 domains: (1) Participants (Performers and Peers); and (2) Program (Partnerships, Practicalities, and Prevention). Conclusions: Exposure to a DST performance improved knowledge and risk perceptions about addiction among middle and high school students. It remains to be seen if those changes can have an effect on the prevention of substance use and dependence among vulnerable youth, and whether the active components of DST can be replicated in other school environments.

Effect of a pre-milking teat foam and a liner disinfectant on the presence of mesophilic and (proteolytic) psychrotrophic bacteria prior to milking

2019 ◽  
Vol 86 (4) ◽  
pp. 432-435 ◽  
Author(s):  
M. Verhegghe ◽  
J. De Block ◽  
S. Van Weyenberg ◽  
L. Herman ◽  
M. Heyndrickx ◽  
...  
Keyword(s):  
Hydrogen Peroxide ◽  
Raw Milk ◽  
Minor Effect ◽  
Active Components ◽  
Trinitrobenzenesulfonic Acid ◽  
Bacterial Counts ◽  
Uht Milk ◽  
Psychrotrophic Bacteria ◽  
Before And After ◽  
A Minor

AbstractContamination of raw milk by psychrotrophs can lead to the production of heat-resistant proteases and subsequent spoilage of UHT milk. Therefore, this research communication evaluated the effect of a pre-milking teat disinfectant (active components: L-(+)-lactic acid and salicylic acid) and a liner disinfectant (active components: peracetic acid and hydrogen peroxide) on the number of mesophilic and (proteolytic) psychrotrophic bacteria prior to milking. The teat orifices of 10 cows were sampled using a swabbing procedure before and after treatment with a pre-milking teat disinfectant on six subsequent days. On the teat orifices, there was a small but statistically significant decrease in the psychrotrophic bacterial counts between pre and post dipping. No differences were observed for the mesophilic bacterial counts and proteolytic active counts. Liners were also sampled using swabs pre and post disinfection. No statistically significant decrease in the bacterial counts was observed post liner disinfection, although there was a numerical decrease. Sixty-two percent of the proteolytic psychrotrophs were pseudomonads: 16.5% of which were P. fragi, 14.3% P. lundensis, 10.0% P. fluorescens and 2.9% P. putida. Trinitrobenzenesulfonic acid (TNBS) analysis revealed a wide variety in proteolytic activity (from 0 to 55 µmol glycine/ml milk) and the presence of high producers. It can be concluded that there was only a minor effect of teat and liner disinfection on the psychrotrophic bacterial counts indicating that the measures presented did not result in a reduction of the targeted bacteria on teat orifices and liners.

Effects of Solvents on the Electrical Resistance of Poly(3,4-ethylenedioxythiophene) on Textiles

2012 ◽  
Vol 441 ◽  
pp. 16-22 ◽  
Author(s):  
Serkan Yildiz ◽  
Jin Lin Cai ◽  
Qin Guo Fan
Keyword(s):  
Electrical Resistance ◽  
Chemical Resistance ◽  
Morphological Changes ◽  
Chemical Treatments ◽  
Before And After ◽  
Order Of Magnitude ◽  
Polyester Textile ◽  
Coated Fabrics ◽  
Vapor Phase Polymerization ◽  
Almost All

The chemical resistance of Poly-3,4-ethylenedioxythiophene (PEDOT) was tested in both organic and inorganic solvents including Chloroform, DMSO, Xylene, THF, sulfuric acid, sodium hydroxide and sodium chloride. PEDOT was synthesized via the vapor-phase polymerization and coated on PET/cotton, cotton and polyester textile substrates. Electrical resistances of the PEDOT were measured both before and after chemical treatments. The morphological changes after treatments were studied by scanning electron microscope (SEM). The PEDOT coated fabrics demonstrated excellent chemical-resistant property since its electrical resistance maintained on the order of magnitude of 100 ohm after treatment in almost all the solvents except NaOH with which a remarkable increasing of electrical resistance occurred due to disappearing PEDOT from the substrate indicating its potential to be a good solvent for PEDOT.

scholarly journals Synergies between Surface Microstructuring and Molecular Nanopatterning for Controlling Cell Populations on Polymeric Biointerfaces

Polymers ◽  
2020 ◽  
Vol 12 (3) ◽  
pp. 655 ◽  
Author(s):  
Andrés Díaz Lantada ◽  
Ravi Kumar ◽  
Markus Guttmann ◽  
Markus Wissmann ◽  
Marc Schneider ◽  
...  
Keyword(s):  
Cell Cultures ◽  
Potential Role ◽  
Eukaryotic Cell ◽  
Innovative Approach ◽  
Cell Populations ◽  
Cell Cultivation ◽  
Molecular Patterning ◽  
Synthetic Materials ◽  
Before And After ◽  
New Generation

Polymeric biointerfaces are already being used extensively in a wide set of biomedical devices and systems. The possibility of controlling cell populations on biointerfaces may be essential for connecting biological systems to synthetic materials and for researching relevant interactions between life and matter. In this study, we present and analyze synergies between an innovative approach for surface microstructuring and a molecular nanopatterning procedure of recent development. The combined set of techniques used may be instrumental for the development of a new generation of functional polymeric biointerfaces. Eukaryotic cell cultures placed upon the biointerfaces developed, both before and after molecular patterning, help to validate the proposal and to discuss the synergies between the surface microstructuring and molecular nanopatterning techniques described in the study. Their potential role in the production of versatile polymeric biointerfaces for lab- and organ-on-a-chip biodevices and towards more complex and biomimetic co-culture systems and cell cultivation set-ups are also examined.

scholarly journals Identification of Tengfu Jiangya Tablet Target Biomarkers with Quantitative Proteomic Technique

2017 ◽  
Vol 2017 ◽  
pp. 1-12 ◽  
Author(s):  
Jingwen Xu ◽  
Yunlun Li ◽  
Shijun Zhang ◽  
Haiqiang Jiang ◽  
Nan Wang ◽  
...  
Keyword(s):  
Therapeutic Process ◽  
Protein A ◽  
Retinol Binding Protein ◽  
Active Components ◽  
Absolute Quantitation ◽  
Retinol Binding Protein 4 ◽  
Total Alkaloids ◽  
Before And After ◽  
Proteomic Study ◽  
Isobaric Tags

Tengfu Jiangya Tablet (TJT) is a well accepted antihypertension drug in China and its major active components were Uncaria total alkaloids and Semen Raphani soluble alkaloid. To further explore treatment effects mechanism of TJT on essential hypertension, a serum proteomic study was performed. Potential biomarkers were quantified in serum of hypertension individuals before and after taking TJT with isobaric tags for relative and absolute quantitation (iTRAQ) coupled two-dimensional liquid chromatography followed electrospray ionization-tandem mass spectrometry (2D LC-MS/MS) proteomics technique. Among 391 identified proteins with high confidence, 70 proteins were differentially expressed (fold variation criteria, >1.2 or <0.83) between two groups (39 upregulated and 31 downregulated). Combining with Gene Ontology annotation, KEGG pathway analysis, and literature retrieval, 5 proteins were chosen as key target biomarkers during TJT therapeutic process. And the alteration profiles of these 5 proteins were verified by ELISA and Western Blot. Proteins Kininogen 1 and Keratin 1 are members of Kallikrein system, while Myeloperoxidase, Serum Amyloid protein A, and Retinol binding protein 4 had been reported closely related to vascular endothelial injury. Our study discovered 5 target biomarkers of the compound Chinese medicine TJT. Secondly, this research initially revealed the antihypertension therapeutic mechanism of this drug from a brand-new aspect.

scholarly journals Pesticide use is linked to increased body size in a large mammalian carnivore

2020 ◽  
Vol 131 (1) ◽  
pp. 220-229
Author(s):  
M Letnic ◽  
M S Crowther
Keyword(s):  
Body Size ◽  
Body Mass ◽  
Intraspecific Competition ◽  
Chemical Resistance ◽  
Prey Availability ◽  
Phenotypic Change ◽  
Pesticide Use ◽  
Skull Length ◽  
Before And After

Abstract Pollution and pesticide use have been linked to evolution of chemical resistance and phenotypic shifts in invertebrates, but less so in vertebrates. Here we provide evidence that poisoning directed towards a mammalian carnivore, the dingo (Canis dingo), is linked to an increase in dingo body mass. We compared the skull length of dingoes, a proxy for size, from three regions where dingo populations were controlled by distributing poisoned meat baits and an unbaited region, before and after the introduction of the toxin sodium fluoroacetate (Compound 1080). Following 1080 introduction, dingo skull length increased in baited regions but not in the unbaited region. We estimate that after 1080 introduction, the skull length of female and male dingoes in baited regions increased by 4.49 and 3.6 mm, respectively. This equates to a 1.02- and 0.86-kg increase in mean body masses of female and male dingoes, respectively. We hypothesize that dingo body size has increased in baited regions due to 1080 selecting for animals with larger body size or because a reduction in dingo abundance in baited areas may have removed constraints on growth imposed by intraspecific competition and prey availability. Our study provides evidence that pesticide use can prompt phenotypic change in comparatively large and long-lived large vertebrates.

scholarly journals The Oxygen Transfer Capacity of Submerged Plant Elodea densa in Wastewater Constructed Wetlands

Water ◽  
2019 ◽  
Vol 11 (3) ◽  
pp. 575 ◽  
Author(s):  
Andrzej Białowiec ◽  
Karolina Sobieraj ◽  
Grzegorz Pilarski ◽  
Piotr Manczarski
Keyword(s):  
Wastewater Treatment ◽  
Oxygen Concentration ◽  
Constructed Wetlands ◽  
Oxygen Transfer ◽  
Municipal Wastewater ◽  
Tap Water ◽  
Mass Unit ◽  
Elodea Densa ◽  
Before And After ◽  
Oxygen Transfer Capacity

There are insufficient data for the development of process design criteria for constructed wetlands systems based on submerged plants as a major treatment agent. The aim of the study was to evaluate the oxygen transfer capacity (OTC) of E. densa, in relation to wet plants’ mass (w.m.), and the influence of E. densa on the oxygen concentration and contaminants’ removal efficiency from municipal wastewater. The obtained oxygen concentration and temperature data allowed to calculate the OTC values (mg O2·L−1·h−1), which had been related to wet plants’ mass unit (mg O2·L−1·h−1·g w.m.−1). The efficiency of wastewater treatment was determined in relation to initial wastewater content in the mixture of wastewater and tap water (0%, 25%, 50%, and 100%) during 3 days of the experiment duration. The simulation of day and night conditions was done by artificial lighting. Before and after finishing the second experiment, the COD, Ntotal, and P-PO4 concentration were analyzed in wastewater solutions. The OTC ranged from 3.19 to 8.34 (mgO2·L−1·h−1·g w.m.−1), and the increase of OTC value was related to the increase of wet plant’s mass. The research showed that E. densa affected positively on the wastewater treatment efficiency, and the highest efficiency was achieved in 25% wastewater solution: 43.6% for COD, 52.9% for Ntotal, 14.9% for P-PO4.

Preparation and Characterization of Palladium-Gold/4A Zeolite Catalyst

2013 ◽  
Vol 634-638 ◽  
pp. 571-574
Author(s):  
Xian Zhong Mo ◽  
Hua Lin Hu ◽  
Ting Gou ◽  
Guo Song Sun ◽  
Bing Rong Mo
Keyword(s):  
Catalytic Activity ◽  
Zeolite Catalyst ◽  
Absorption Spectrometry ◽  
Xrd Analysis ◽  
Sem Analysis ◽  
X Ray Diffraction ◽  
Active Components ◽  
4A Zeolite ◽  
Alloy Particles ◽  
Before And After

Palladium-Gold(Pd-Au)/4A zeolite catalyst was prepared by using 4A zeolite as carrier and Pd-Au as active components. The structure of Pd-Au/4A zeolite catalyst was characterized by a combination of atomic absorption spectrometry (AAS), scanning electron microscopy (SEM) and X-ray diffraction (XRD).The AAS testing showed that Pd and Au supported rate were increased up to the maximum 93.88% and 90.22% respectively at the ratio of Pd/Au=1.16. The SEM analysis results indicated that Pd-Au alloy particles of 4A zeolite catalyst can grown up and reunited obviously through before and after reaction. The XRD analysis results showed that diffraction peak of Pd(111), Pd(200), Au(111) and Au(200) became sharp gradually with the extension of reaction time, crystalline phase composition and grain size of catalyst became bigger gradually. The catalytic activity of the Pd-Au /4A zeolite catalyst was elaborated in vinyl acetate synthesis and the results showed that Pd-Au/4A zeolite catalyst has excellent catalytic activity.

scholarly journals Biopolimeric Nano Structural Compositions Based on Caramelized Honey

2019 ◽  
Vol 20 (4) ◽  
pp. 445-452
Author(s):  
S.А. Кurta ◽  
О.М. Khatsevich ◽  
М.R. Tsap ◽  
D. Ondrušová ◽  
T.M. Gromovy ◽  
...  
Keyword(s):  
Chemical Properties ◽  
Biochemical Properties ◽  
Biologically Active ◽  
Chewing Gum ◽  
Periodontal Tissue ◽  
Active Components ◽  
Biochemical Activity ◽  
Prevention And Treatment ◽  
Before And After ◽  
The Difference

The article deals with chemical properties of honey as well as wax and beeglue before and after the process of caramelization. The research has been done to study chemical reactions of caramelization of honey and other bee products; the biochemical properties of the obtained substances have been investigated as well. It has been revealed that biological activity of the compound after thermochemical heating of honey in the presence of special catalysts was discovered. Infrared spectra, moisture, viscosity, size and distribution of nanoparticles, elemental composition, oxymethylfurfural content, diastase number  of caramelized honey have been investigated. The difference between the sizes of nanoparticles of raw and caramelized honey has been revealed, namely caramelized honey (1.5-2.0 times) of smaller size encourages their biochemical activity. On the basis of the results obtained from caramelized honey, wax and beeglue as well as their properties, the chewing gum with biologically active components for the prevention and treatment of periodontal tissue diseases (gingivitis, periodontitis and periodontal disease) was invented. Clinical studies on chewing gum with honey, wax, and beeglue have confirmed that it provides health benefits among 72 % of patients.

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