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YMER Digital ◽  
2021 ◽  
Vol 20 (12) ◽  
pp. 683-693
Author(s):  
P Supriya Prasad ◽  
◽  
M Deepa ◽  
T Gomathi ◽  
P.N Sudha ◽  
...  

Agricultural wastes like sugarcane bagasse, rice husk, wheat husk, rice hull are the cheapest sources of biosilica (BS). In this study, sugarcane bagasse was used to extract biosilica by chemical treatment and combined with silk fibroin (SF), Polyurethane Foam (PUF) and TiO2 to prepare a novel biocomposites BS/SF/PUF and BS/SF/PUF/TiO2. The prepared biocomposites were analyzed using FT-IR and SEM analysis. The presence of various functional groups and the formation of biocomposites were confirmed by the FT-IR studies. The SEM analysis displayed rough surface morphology of the biocomposites. The antioxidant properties were studied using the DPPH assay. The biocomposites exhibited excellent antioxidant properties. The antimicrobial activities of the biocomposites were studied against three bacterial (Bacillus sp., Klebsiella sp. and Proteus sp.) and three fungal strains (Rhizopus sp., Aspergillus niger and Candida sp.). The results revealed that the prepared biocomposites were active against the selected bacterial and fungal species


2021 ◽  
Author(s):  
M Sankareswaran ◽  
M Vanitha ◽  
P. Rajiv ◽  
A. Anbukumaran

Abstract The current investigation reports on a green route, simple and eco-friendly method for synthesis of silica nanoparticles from Phyllantus emblica. Appropriate characterization techniques were employed to assess the crystalline nature, microstructure, size, purity, elemental composition and stability of as-biosynthesized silica nanoparticles. The XRD analysis showed a wide-ranging peak at 22∘ of 2θ value and proved that the nanoparticles were crystalline nature with 32 nm average size of particles. FT-IR studies confirmed the occurrence of metal oxide group and presence of phyto-molecules namely hydroxyl, amide, and carboxyl functional groups, which were responsible for formation and stabilization of silica nanomaterials. TGA and Zeta potential analysis determined that silica nanoparticles are highly thermostable. EDX analysis revealed the purity of nanomaterials and spectra confirmed that formation of silica nanomaterials (72.97 weight percentage of SiO2 content) with low impurities. SEM analysis shows that the particles are spherical in shape with low agglomeration. This research work concluded that the P. emblica was an excellent and reliable green resource for production of highly stable and potential silica nanoparticles.


2021 ◽  
Author(s):  
Leslie Pereira ◽  
Antonio Gilcler F. Lima ◽  
Marcella T. Ferreira ◽  
Camila Salata ◽  
Samara C Ferreira-Machado ◽  
...  

Abstract Introduction: Breast cancer (BC) is the most common female malignancy worldwide. For the definitive treatment of MC, radiotherapy can be used, as an important component, and uses ionizing radiation (IR). Studies reveal the potential capacity of IR to promote metastasis. The clinical response of BC to radiotherapy is related to radiosensitivity and resistance of irradiated cells, which is associated with clonogenic activity and sensitivity to radiation. Unsuccessful treatment increases the risk of local and distant recurrence.Methodology: Three breast cell lines (MCF-10A, MCF-7, and MDA-MB-231) were irradiated with 2 Gy and after 72 hours following markers were evaluated: E-cadherin, fibronectin, vimentin, and Snail. The processes of invasion, degradation of MMP2 and MMP9, and transendothelial migration were then assessed. Double-strand DNA breaks (DSBs), apoptosis, and colony formation were quantified. Result: The detection of γH2AX histone of irradiated cells showed that MCF-10A non-tumor cell is more radiosensitive while the MDA-MB-231 tumor cell is more radioresistant. The dose 2 Gy altered the formation of colonies to any of the cell lines. Tumorigenic cells exhibited a markedly increase in apoptosis, 24 h after irradiation while MCF-10A cells only after 72 h. A single dose of 2 Gy does not induce changes in the cellular microenvironment that lead to changes in the mesenchymal epithelium in breast BC.Conclusion: A dose of 2 Gy induces apoptosis and consequently an alteration in cell survival. However, a single dose of 2 Gy does not induce changes in the cellular microenvironment that lead to changes in the mesenchymal epithelium.


Author(s):  
Ruchi Tiwari ◽  
Akanksha Lahiri ◽  
Gaurav Tiwari ◽  
Ramachandran Vadivelan

The present study assessed the topical potential of nanofibers loaded with Mupirocin (MUP) for the treatment of burns. Nanofibers of MUP were composed of Polyvinyl Pyrrolidone (PVP), Gelatin Type-A, and Ethanol using two methods: Solvent casting and Electrospinning. Nanofibers were characterized for Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), Differential scanning calorimetry (DSC), Thermogravimetric analysis (TGA), Drug Content Studies, in-vitro drug permeation, antibacterial and stability studies. The FT-IR studies showed that the Electrospinning technique had a very good mixing of MUP with the polymer. SEM studies showed that the morphology of electrospinning nanofibers had diameters in the range of 70.41 nm- 406.83 nm. The thermal decomposition studies of optimized Nanofiber (E.S.1) were performed by DSC and TGA study and it was found that the formulation had high stability in high-temperature environments. Permeation studies showed that E.S.1 had the highest percentage amount and controlled release of the drug (90 %) up to 8 has compared to other formulations. Nanofibers prepared through the Electrospinning technique showed better antibacterial activity against Staphylococcus aureus as compared to the Solvent casting nanofibers. This research suggested that MUP loaded nanofibers can be potentially used as a topical drug delivery system for the treatment of burns. 


Religions ◽  
2021 ◽  
Vol 12 (11) ◽  
pp. 982
Author(s):  
Joanna Kulska ◽  
Anna M. Solarz

In spite of the increasing presence of religion in international relations with various publications observing this presence and numerous authorities calling for the inclusion of religion into mainstream research, there is no universal consent to recognize religion’s role in IR. In our opinion, the only way to reconcile IR with the international reality in which religion has been and will remain present in the foreseeable future is for the researchers themselves to construct—especially those oriented towards broad, non-Western perspective—a new face of the discipline, the face which in this article we call the post-secular identity of IR study. Assuming that identity is first and foremost a form of knowledge that tells us how we can define ourselves against the background of the surrounding world, our purpose is to look at the post-secular identity from two different perspectives which are analyzed in the two distinctive parts of the paper. On one hand, post-secular identity would mean the socio-political but also cultural phenomenon of the “knowledge of the self” expressed in the form of ideas, interests and goals of various state and nonstate actors, both religious and secular ones, that are more or less conditioned by religious determinants. We propose looking at them through the prism of a new kind of “partnership” emerging as a result of post-secular thinking in the area of IR. On the other hand, we want to look at post-secular identity as the badly required transformation within the area of IR study that, as we claim, needs to construct more inclusive views of IR scholars adopting a deliberative and pluralistic approach to the reality they examine based on widening their epistemological and hermeneutical horizons. This redefinition would be framed by recognizing religion as rational and adopting the view that the limits of the scientific methods do not coincide with the boundaries of rationality. We also adopt the view that along with the cognitive expansion of the universe, the concept of transcendence has been broadened.


Molecules ◽  
2021 ◽  
Vol 26 (20) ◽  
pp. 6261
Author(s):  
Łukasz Kuterasiński ◽  
Mariusz Gackowski ◽  
Jerzy Podobiński ◽  
Dorota Rutkowska-Zbik ◽  
Jerzy Datka

One of the methods of IR studies of the heterogeneity of Si–OH–Al groups in zeolites is the investigation of the frequency shift of the band of free OH bands restored upon the adsorption of ammonia and subsequent desorption at increasing temperatures. We extended this method by following the shift of the band of the OH group interacting by hydrogen bonding with nitrogen. The advantage of nitrogen, compared with CO, which has been commonly used as a probe molecule in studies on hydrogen bonding, is that for nitrogen the frequency shift is smaller than for CO and therefore there is no overlapping of shifted OH band with the bands of ammonium ions. For zeolites NaHY, HMFI, and HBEA, the frequency shift of IR bands of both free and hydrogen-bonded Si–OH–Al with the increase of ammonia desorption temperature evidences the heterogeneity of these hydroxyls. On the other hand, in zeolite HFAU of Si/Al = 31, Si–OH–Al were found to be homogeneous. Heterogeneity of OH groups may be explained both by the presence of Si–OH–Al of various number of Al near the bridge and of Si–OH–Al of various geometry.


Materials ◽  
2021 ◽  
Vol 14 (19) ◽  
pp. 5535
Author(s):  
Piotr Kobędza ◽  
Aleksandra Smejda-Krzewicka ◽  
Krzysztof Strzelec

The purpose of this work was to verify the ability to cross-link the chloroprene rubber (CR) by using copper oxides: copper(I) oxide or copper(II) oxide. The use of copper oxides arises from the need to limit the application of ZnO as a cross-linking agent of CR. The obtained results indicate that CR compositions cross-linked with copper oxides are characterized by good mechanical properties and a high cross-linking degree. The results show that the type and the amount of copper oxides influence the cross-linking of the CR and the properties of the vulcanizates. For compositions containing copper(II) oxide, the properties are linearly dependent on the amount of CuO. Such a relationship is difficult to notice in the case of the use of copper(I) oxide—when analyzing individual parameters, the best results are obtained for different samples. Infrared spectroscopy (IR) studies confirmed the possibility of cross-linking of chloroprene rubber with copper oxides. This is evidenced by the characteristic changes in the intensity of the bands. Structural changes in the material during heating were determined by the thermal analysis—differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). Regardless of the type and amount of copper oxide, all compositions exhibit similar characteristics, and there are no significant changes in the glass transition temperature of the material.


2021 ◽  
Vol 01 ◽  
Author(s):  
Shruthy D. Pattathil ◽  
Satish A. Ture ◽  
Ramon Martinez-Manez ◽  
Venkataraman Abbaraju

Background: Detection of explosives (Nitroaromatic compounds) is one of the major issues faced in global security and to date remains a challenge even though some materials are developed for their detection. This study introduces the use of polyvinylpyrrolidone (PVP), a non-conjugated conducting polymer as a potential fluorophore for sensing nitroaromatics. The stimuli - response of fluorescence of PVP on interaction with energetic nitroaromatics was investigated in the present study. Methods: Fluorescence quenching studies of 5% PVP was carried out by the addition of varying concentration of quenchers (m-dinitrobenzene, trinitrobenzene and 2,4,6-trinitrophenol). To study the effect of different solvents on fluorescence quenching, two different solvents were used i.e., water and ethanol. The quenching studies of PVP with dinitrobenzene and trinitrobenzene was carried out in ethanol and 2,4,6-trinitrophenol was carried out in water. Results: The maximum emission peak intensity of PVP was observed at 445nm in ethanol and 420nm in water which was quenched upon gradual addition of quenchers. This shift in maximum peak intensity of PVP was understood from the change in the solvent polarity. UV-Visible and FT-IR studies were also carried out to understand the nature of interaction taking place between the quenchers and PVP. The limit of detection (LOD) was observed as 1.8x10-3M, 2.5x10--6M, and 3.9x10-6 M for picric acid, dinitrobenzene andtrinitrobenzene respectively. Conclusion: The results envisage PVP as a potential candidate for sensing energetic nitroaromatics with good sensitivity.


Author(s):  
Deepak Sarangi ◽  
Subhashree Mallick ◽  
Anjum Ara ◽  
Sanjeeb Kumar Sahoo ◽  
Rabinarayan Rana

Olmesartan Medoxomil is an AT1 subtype selected angiotensin-II receptor antagonist approved for the treatment of hypertension. It has low water solubility, so the current effort is being made to enhance the solubility of the Olmesartan by inclusion complex and to incorporate them into tablets by direct compression. Complexing agent like Beta cyclodextrin and polyvinyalpyrrolidone has been used for complexation method. FT-IR studies have shown that there is no link between drugs and complexing agents. Among all methods, the inclusion complex (OLBCD 3) containing the drug: Beta cyclodextrin in a 1: 3 ratio showed rapid drug release (87.41% within 30 minutes) and post compression parameters are within limits. All the values obtained from pre compression and post compression parameters meets the legal requirements for tablets. Stability studies of batch no OLBCD 3 shows no significant change. Therefore, it can be concluded that the structure was stable.


Author(s):  
Matteo Dian

Abstract East Asia is increasingly at the centre of debates among International Relations (IR) scholars. China's political, economic, and military ascendency is increasingly considered as a crucial test case for main approaches to IR. Despite this renewed attention, mainstream theories employed to analyse contemporary Asia are still remarkably Euro-centric. A wave of studies has argued in favour of a broad ‘decolonization’ of theoretical concepts used to analyse East Asia as well as other regions. These efforts have produced several distinct research agendas. Firstly, critical and post-colonial theorists have worked on the par destruens, highlighting the inherent Euro-centrism of many IR concepts and theories. Secondly, scholars such as Buzan and Acharya have promoted the idea of Global IR, seeking to advance a ‘non-Western’ and non-Euro-centric research agenda. This agenda has found fertile ground especially in China, where several scholars have tried to promote a Chinese School of IR. This article has three main purposes. Firstly, it briefly explores the issue of Eurocentrism in IR studies dedicated to East Asia. Secondly, it maps the theoretical debates aimed at overcoming it, looking in particular at the ‘Global IR’ research programme and the so-called Chinese School. Finally, it sketches a few other possible avenues of research for a very much needed cooperation between Global IR and area studies.


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