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For a reliable and risk-free power source, dye-sensitized solar cells (DSSCs) have been the subject of much research. The method is very attractive because of its cheap manufacturing cost, environmentally friendly manufacture, and competitive efficiency. This study constructed a heterojunction as a photoanode for DSSCs using a combination of TiO2 and graphene using a wet chemical technique. According to the XRD and TEM findings, the graphene sheets consist of evenly wrapped spherical nanoparticles with diameters ranging from 30 to 40 nm, and the TiO2 exhibits a tetragonal (anatase) phase. It is common for anatase to have a bandgap energy of 3.15 eV for TiO2, whereas graphene/TiO2 has a bandgap energy of 2.77 eV. With a power conversion efficiency (PCE) of 7.2%, graphene/TiO2 DSSCs outperform cells based on pure TiO2 electrodes by a margin of 2.22%. In particular, graphene's ability to absorb solar light has the potential to improve the power conversion efficiency of DSSCs by increasing the light harvest of dye molecules. In addition, graphene/TiO2 had an average electron transit time of 1.765 ms while TiO2 had an average of 2.981 ms. The research shows that DSSCs' power conversion efficiency may be greatly improved by strategically adding graphene, which can be affordably synthesized, to certain layers of the photoanode. [ABSTRACT FROM AUTHOR]

In this paper, we obtain the generalized distance spectra of the graphs constructed by 19 unary and 21 binary graph operations of M-join type when the constituting graphs satisfy some conditions. Also, we deduce a result on the generalized distance spectrum of the double graph of a connected regular graph in the literature. As applications, we construct infinite families of generalized distance cospectral graphs. Also, we construct infinite families of distance (distance Laplacian, distance signless Laplacian) integral graphs. [ABSTRACT FROM AUTHOR]

Seaweed extracts are extensively used as fertilizers across the globe. However, their mechanism of action and effects are less understood and need to be studied in detail. The present study investigated the effect of Ulva lactuca seaweed extract as a liquid fertilizer (SLF) on the growth characteristics of green gram. The seeds of green gram were soaked in varied concentrations of aqueous seaweed extract like 2, 4, 6, 8 and 10 %. Additionally, the SLF was applied on germinated seedlings as foliar spray treatment in 2 days interval. The maximum growth parameters were observed in foliar spray treatment at 8 % concentration and in seed soaking treatment at 2 % concentration. The seaweed extract was effective in influencing the growth characteristics of green gram. [ABSTRACT FROM AUTHOR]

Rice is grown by transplanting under wetland conditions or by direct sowing depending upon the availability of water. In India, the total area under irrigated rice is about 22.00 million hectares, which accounts for about 49.5 per cent of the total area under rice crop in the country. Upland rice fields are generally dry and directly seeded. In India, the total area under upland rainfed rice is about 6.00 million hectares, which accounts13.5 per cent of the total area under rice crop in the country. Wet seeding of rice is practiced when there is insufficient time to prepare the nursery for transplanting or when the cost of transplanting of rice is too high. Sowing is done either by broadcasting or with equipment like drum seeder. Manually operated drum seeder has drawbacks like a scattering of seeds, dislocation of seeds due to surface water or rain and seeds being picked up by pests, etc. Asystem for accurately placing multiple seeds in hills will eliminate the above problems. Hence a method of sowing pelletized rice was developed. The seed pellets will be sown by a seeder in a wet rice field. In this present study, a projected seed cell vertical rotor device of 120 mm diameter with 12 cells on the rotor periphery was evaluated. The parameter used to evaluate the sowing performance were rotor speeds of 8, 11, 14, 16 and 20 rpm, seed sizes of 8 to 9 mm, 9 to 10 mm and 10 to 11mm diameter, cell sizes of 10, 11, 12 mm and three depths of seeds in hopper as 10, 20 and 30 mm above the disc center line. Due to the non singulation of seeds, 60 mm rotor was dropped. Hence 120 mm vertical rotor seed metering mechanism was selected for sowing in field condition. [ABSTRACT FROM AUTHOR]

Creatinine is a kidney dysfunction biomarker, and its sensing properties have become an important tool in the diagnosis of abnormal kidney function. In the present study, a new enzyme-less creatinine sensor was developed by the bulk modification of carbon paste with the as-prepared inulin-based bio-nanocomposite. The electrochemical sensing of creatinine was conducted using the a sensor that exhibited two linear working ranges of 0.2 μM to 1 μM and 0.05 mM to 12 mM with the corresponding limits of detections of 60 nM and 90 μM. The sensitivity (204 mA mM cm−2), selectivity (in presence of other interferences like glucose, urea, ascorbic acid and uric acid) and stability (240 days) were also established. The sensitivity of the fabricated electrode was further validated by the determination of creatinine in urine samples spiked with various concentrations of creatinine. The analytical performance of the electrode was compared with that of the standard spectrophotometric method. This implied the better sensitivity of the fabricated sensor with nM-level sensing, which is a million times higher than that obtained using the spectrophotometric method. [ABSTRACT FROM AUTHOR]

• Sensing trace level of glucose in commercial food products is important. • CP/MWCNT-Inulin-TiO 2 /GOx, a new kind of electrode was fabricated for sensing glucose. • Nanomolar sensing of glucose in sugar free products was achieved using the electrode. • Study revealed that some of the sugar free products were not 100% glucose free. • Storage stability (150 days) was higher than that of other carbon based electrodes. Development of an effective sensor for sensing glucose in commercially available "sugar free" food products is important as people are becoming diabetic health conscious. Although multi-walled carbon nanotubes (MWCNTs) possess interesting electrical properties, their hydrophobic nature limits their applications. Their hydrophilicity can be improved through modification. In the present study, Inulin, that was isolated from Allium sativum L. using hot water diffusion and incorporated with titanium dioxide (TiO 2), was used for the modification of MWCNTs. The as-synthesized MWCNT-Inulin-TiO 2 bio-nanocomposite immobilized with glucose oxidase (GOx) was incorporated into the carbon paste matrix and was utilized for the sensing of glucose in food products. Differential pulse voltammetric studies revealed that the fabricated electrode demonstrated good linear range (1.6 nM to 1 μM) and was sensitive to nanomolar concentrations of glucose with a very low limit of detection up to 0.82 nM and exhibited a long term stability of 150 days. [ABSTRACT FROM AUTHOR]

In the field of modern dentistry, ideal three-dimensional positioning of dental implant with optimal prosthetic fit offers successful long-term outcomes. To achieve such accurate implant placement, presurgical evaluation of hard and soft tissue matters the most. Their efforts can be attained using various application programs such as digital imaging, implant planning software, laboratory- or computer-assisted surgical guides, and dynamic navigation approach. To overcome different opinions and choices regarding guided surgery, this article explains an evidence-based literature review to assess its various outcomes and allowing informed choices before using various guided surgical techniques based on its expectation and reality outcomes. This highlights a clinician's choice to guide his successful implant surgery without causing distress in the midway of treatment. An online search was done on PubMed/Medline database to bring in accuracy to the expertise. This review includes reference of publications from 2000 to 2019, which is related to promising outcomes using computer-assisted static or dynamic navigation system for the placement of implant. Out of these, 809 were related to the computer-guided implant placement. Relevant papers were chosen in accordance with the inclusion and exclusion criteria. This review article contemplates to reflect the fact that computer-guided approach is considered to offer more predictable, safer, and faster implant placement with the predetermined final prosthetic outfit. Thus, digital planning and placing of dental implants in the correct position keep escalating to a higher achievement levels than a classical freehand approach. Nevertheless, this guided surgical approach also holds some errors and risks, which must be identified and rectified., Competing Interests: There are no conflicts of interest., (Copyright: © 2020 Indian Society of Periodontology.)

Microperoxidase-11 (MP-11), a heme undecapeptide obtained by proteolytic digestion of cytochrome c, resembles peroxidase enzyme when its heme center is 5-coordinated with a vacant sixth coordination site. However, MP-11 always tends to aggregate in both solution and on surface and eventually forms the 6-coordinated heme. Thus, the present study investigates the immobilization strategy of MP-11 on nanoparticle surface in order to generate monomeric 5-coordinated MP-11 and make them as an efficient biocatalyst. The powerful surface-enhanced resonance Raman scattering (SERRS) technique is being employed to attain the detailed structural information of the catalytic site i.e., the heme center. The localized surface plasmon resonance (LSPR) tuned and 6-mercaptohexanoic acid (MHA) functionalized silver nanoparticles (Ag@MHA NPs) are used as Raman signal amplifier. The outcome of the SERRS study unambiguously portrays the existence of monomeric 5-coordinated MP-11 on Ag@MHA NPs surface. Here, Ag@MHA NPs plays a dual role of providing a platform to create monomeric 5-coordinated MP-11 and to load large number of MP-11 due to its high surface to volume ratio. Further, the electrostatic interaction between Ag@MHA NPs and MP-11 leads to instantaneous SERRS signal enhancement with a Raman enhancement factor (EFSERS) of 2.36×10(6). Langmuir adsorption isotherm has been employed for the adsorption of MP-11 on Ag@MHA NPs surface, which provides the real surface coverage (ΓS(*)) and equilibrium constant (K) value of 1.54nm and 5×10(11)M(-1). Furthermore, the peroxidase activity of MP-11 has been demonstrated through electrocatalytic oxygen reduction reaction., (Copyright © 2016 Elsevier B.V. All rights reserved.)

This paper demonstrates a renewed procedure for the quantification of surface-enhanced Raman scattering (SERS) enhancement factors with improved precision. The principle of this method relies on deducting the resonance Raman scattering (RRS) contribution from surface-enhanced resonance Raman scattering (SERRS) to end up with the surface enhancement (SERS) effect alone. We employed 1,8,15,22-tetraaminophthalocyanato-cobalt(II) (4α-Co(II)TAPc), a resonance Raman- and electrochemically redox-active chromophore, as a probe molecule for RRS and SERRS experiments. The number of 4α-Co(II)TAPc molecules contributing to RRS and SERRS phenomena on plasmon inactive glassy carbon (GC) and plasmon active GC/Au surfaces, respectively, has been precisely estimated by cyclic voltammetry experiments. Furthermore, the SERS substrate enhancement factor (SSEF) quantified by our approach is compared with the traditionally employed methods. We also demonstrate that the present approach of SSEF quantification can be applied for any kind of different SERS substrates by choosing an appropriate laser line and probe molecule.

Optically tuned silver nanoparticles (AgNP's) functionalized with ω-mercaptoalkanoic acids are synthesized and used as a signal amplifier for the surface-enhanced resonance Raman scattering (SERRS) study of heme cofactor in methemoglobin (metHb). Even though both mercaptopropionic acid (MPA)- and mercaptononanoic acid (MNA)-functionalized AgNP's exemplify vastly enhanced SERRS signal of metHb, MNA-AgNP's amplify the SERRS signal amid preservation of the nativity of the heme pocket, unlike MPA-AgNP's. The electrostatic interaction between MNA-AgNP's and metHb leads to instant signal enhancement with a Raman enhancement factor (EF(SERS)) of 4.2 × 10(3). Additionally, a Langmuir adsorption isotherm has been employed for the adsorption of metHb on the MNA-AgNP surface, which provides the real surface coverage and equilibrium constant (K) of metHb as 139 nM and 3.6 × 10(8) M(-1), respectively. The lowest detection limit of 10 nM for metHb has been demonstrated using MNA-AgNP's besides retaining the nativity of the heme pocket.

Silver nanoparticles with identical plasmonic properties but different surface functionalities are synthesized and tested as chemically selective surface-enhanced resonance Raman (SERR) amplifiers in a two-component protein solution. The surface plasmon resonances of the particles are tuned to 413 nm to match the molecular resonance of protein heme cofactors. Biocompatible functionalization of the nanoparticles with a thin film of chitosan yields selective SERR enhancement of the anionic protein cytochrome b(5), whereas functionalization with SiO(2) amplifies only the spectra of the cationic protein cytochrome c. As a result, subsequent addition of the two differently functionalized particles yields complementary information on the same mixed protein sample solution. Finally, the applicability of chitosan-coated Ag nanoparticles for protein separation was tested by in situ resonance Raman spectroscopy.