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This paper presents an air-gap torque (AGT)-based method for efficiency estimation of induction motors. A new concept of stator resistance that includes the mechanical losses effect is proposed. This new stator resistance is estimated through a particle swarm optimization approach based on the stator flux equations and minimization of torque error at the rated operation point. Then, the obtained stator resistance is used in the AGT equations to estimate the shaft torque and then the efficiency. Moreover, the rotor speed is estimated using induction motor current signature analysis. Thus, the proposed methodology for induction motor efficiency estimation relies only on line currents, line voltages, and nameplate data, being appropriate for in-service applications. Finally, the simulation and experimental results are presented to validate the proposed method at different load conditions. [ABSTRACT FROM PUBLISHER] more...

Abstract: Reversed chloroquine (RCQ) is a multiple ligand compound active against chloroquine-sensitive and resistant falciparum malaria. It is composed by a 4-aminoquinoline moiety (like that present in chloroquine (CQ)) joined to imipramine (IMP), a modulating agent that also showed intrinsic antiplasmodial activity against Brazilian Plasmodium falciparum isolates resistant to CQ. Molecular modeling and ultraviolet–visible spectroscopy (UV–vis) studies strongly suggest that the interaction between RCQ and heme is predominant through the quinoline moiety in a mechanism of action similar to that observed for CQ. [Copyright &y& Elsevier] more...

In situ surface-enhanced Raman spectroscopy (SERS) was used to monitor the electrochemical behavior of squaric acid on a gold electrode in aqueous solution, at different pH values. Octahydroxycyclobutane and other intermediates were identified. The formation of the squarate radical anion is suggested. The relative intensities of the bands in the SER spectra, together with the surface selection rules, suggest that different adsorption geometries of squaric acid and its deprotonated species are involved. In the presence of chloride, squaric acid and hydrogeno-squarate adsorb via the carbonyl and hydroxyl groups on the electrode surface, whereas their adsorption on metallic thin films occurs mainly via the carbonyl moieties. The observation of carbon monoxide and hydrocarbon bands confirms the catalytic effect of the metallic surfaces investigated in the decomposition of such oxocarbon species. [Copyright &y& Elsevier] more...

Anastrozole is a well‐known anticancer drug used in aromatase‐dependent cancer chemotherapy as a nonsteroidal aromatase inhibitor. Investigations involving the adsorption of anastrozole on gold surfaces are on demand, because gold nanoparticles (AuNPs) have been used as nanocarriers of drugs, and such a compound can be used against aromatase‐expressing neoplastic cells. In this work, surface‐enhanced Raman scattering (SERS) spectroscopy was used to investigate the interaction between anastrozole and the surfaces of AuNPs. Density functional theory (DFT) calculations were used to simulate the molecular interactions with gold atom through two possible ways, triazole or nitrile moieties. Experimental results, supported by DFT calculations to assign main vibrational modes, indicate that the nitrile groups are the most preferred anchorage moieties for the adsorption. [ABSTRACT FROM AUTHOR] more...

Purpose: The objective of this study was to investigate the impact of oral health on the quality of life of patients with head and neck cancer (HNC) before and after oncologic treatment.Methods: Forty cancer-free individuals (Cf group) and 40 HNC patients (Hnc group) were included in this study. Hnc group was also divided into two subgroups: Hnc 1 (pre-cancer therapy, n = 20) and Hnc 2 (post-cancer therapy, n = 20). Participants were asked to complete a short form of Oral Health Impact Profile (OHIP-14). The results were statistically analyzed with the multivariate analysis of variance with post-hoc Scheffé multiple comparison.Results: It was observed a moderate impact on the quality of life on HNC patients, with values on Hnc 2 group significantly higher in the functional limitation when compared to the Hnc 1 group (p < 0.05). When compared to the Cf group, the values found on Hnc group were higher on functional limitation (p < 0.01) and at the total score (p < 0.05), whereas Hnc 2 group had significant superior values on functional limitation (p < 0.01), physical pain (p < 0.05), and total score (p < 0.01) CONCLUSION: These results show that there is an oral impairment that depreciates the quality of life of patients with an experience of HNC, principally after treatment, indicating the importance of the inclusion of professionals responsible for dental and oral care with the oncologic team to monitor the oral condition of these patients. [ABSTRACT FROM AUTHOR] more...

Aim: To answer the following PECO question: "In systemically healthy human subjects (P), which are the differences between peri‐implantitis (E) and peri‐implant health/mucositis (C) in terms of bacterial presence/count (O)?" Materials and Methods: Cross‐sectional studies fulfilling specific inclusion criteria established to answer the PECO question were included. Two review authors independently searched for studies, screened the titles and abstracts, did full‐text analysis, extracted the data from the included reports, and performed the risk of bias assessment through an adaptation of the Newcastle/Ottawa tool for cross‐sectional studies and of the JBI critical appraisal checklist. In case of disagreement, a third reviewer author took the final decision. Study results were summarized using random effects meta‐analyses. Results: A total of 12 studies were included, involving 1233 participants and 1513 implants. Peri‐implantitis was associated with the presence of S. epidermidis (Odds ratio, OR = 10.28 [95% Confidence interval, CI: 1.26–83.98]), F. nucleatum (OR = 7.83 [95% CI: 2.24–27.36]), T. denticola (OR = 6.11 [95% CI: 2.72–13.76]), T. forsythia (OR = 4.25 [95% CI: 1.71–10.57]), P. intermedia (OR = 3.79 [95% CI: 1.07–13.35]), and P. gingivalis (OR = 2.46 [95% CI: 1.21–5.00]). Conversely, the presence of A. actinomycetemcomitans (OR = 3.82 [95% CI: 0.59–24.68]), S. aureus (OR = 1.05 [95% CI: 0.06–17.08]), and C. rectus (OR = 1.48 [95% CI: 0.69–3.17]) was not associated with peri‐implantitis. Conclusions: Peri‐implantitis is associated with the presence of S. epidermidis and specific periodontopathogens (P. gingivalis, T. forsythia, T. denticola, F. nucleatum, and P. intermedia). (CRD42021254589) [ABSTRACT FROM AUTHOR] more...

Abstract: Surface-enhanced Raman scattering (SERS) spectra of the herbicide 2,4-dichlorophenoxyacetic acid (2,4-D) was obtained by employing a bi-layer gold substrate, assembled by the reduction of Au(III) over gold-seeded nanoparticles immobilized on functionalized glass substrates. The SERS signal was linear with the logarithm of the solution concentrations between 1.0×10−7 molL−1 and 1.0×10−3 molL−1, indicating that the bi-layer gold substrate affords a significant dynamic range for SERS, providing an excellent analytical response within this concentration range, and revealing the high sensitivity of the gold surface towards such analyte. In addition, using the same gold substrate, a similar calibration curve was obtained for crystal-violet (CV), and it was possible to identify the concentration limit corresponding to the transition from the average SERS to the nonlinear SERS response. [ABSTRACT FROM AUTHOR] more...

Graphical abstract Highlights • Inulin and modified tiger nut starch were good encapsulating materials. • Microencapsulation increased tiger nut milk (TNM) shelf life. • Microencapsulated tiger nut milk was microbiologically stable. • Tiger nut milk microcapsules were characterized as thermo resistant. Abstract Tiger nut milk is a nutrient rich drink with great commercialization potential. However, it is highly perishable. Microencapsulation of tiger nut milk by a blend of inulin and modified tiger nut starch resulted in a product with good characteristics. The microspheres of lyophilized tiger nut milk were spherical with and average particle size of 1.01 μm. It's thermal degradation occurred above 346 °C, denoting an excellent thermal resistance. There was no significant structural alteration in the active material after microencapsulation and no loss of stability within 60 days, which confirms that this process enables the preservation of freshness and chemical characteristics of tiger nut milk. During 30–90 days, vitamin C contents were stable in the presence or absence of light. Microsphere with tiger nut milk presented a shelf life of 60 days. Total aerobic mesophiles and total fungi counts were below 106 CFU/mL, showing good microbiological stability. [ABSTRACT FROM AUTHOR] more...

Abstract In this work, glass compositions in the system NaPO 3 - Sb 2 O 3 – CuO (PSbCu) containing different concentrations of CuO and Sb 2 O 3 were prepared through the melt - quenching methodology. Thermal, structural and optical properties of the PSbCu glasses were systematically studied by differential scanning calorimetry (DSC), X – ray powder diffraction (XRD) and Raman, UV–Visible and Photoluminescence (PL) spectroscopies, besides electron paramagnetic resonance (EPR) measurements. The DSC curves for all samples presented the glass transition phenomenon (T g), while the XRD patterns showed the presence of an amorphous halo, which confirmed the glassy nature of all samples analyzed. UV–Vis spectra of the glasses showed a transparent window from 450 to 800 nm. The EPR signals intensities were investigated as a function of the copper concentration and Sb 2 O 3 content in the (P y Sb 0.5 Cu) (20 ≤ y ≤ 80) and (PSb80 x Cu) (0.25 ≤ x ≤ 1.25) glasses. The EPR results showed that the increase of Sb 2 O 3 concentration on the P y Sb0.5Cu glasses decreased the Cu2+ signals, which suggests the Sb3+ oxidizing to Sb5+, also transferring electrons to Cu2+ species to create the EPR a silent Cu+ specie. According to EPR parameters and PL spectra (excited at 380 nm) of P y Sb0.5Cu glasses, the ions Cu2+ ions were preferentially found in a distorted octahedral geometry, while Cu+ is in a square planar geometry according to the Jahn-Teller effect. Highlights • Antimonate glasses were prepared by the melt-quenching method. • Antimony (III) oxide promotes the reduction of Cu2+ to Cu+ ions. • EPR parameters showed that the Cu2+ ions were preferentially found in a distorted octahedral geometry. [ABSTRACT FROM AUTHOR] more...

Highlights • SERS is an extremely useful method to detect adsorbed molecules which are covalently bonded to the metallic Ag-NP. • SERS signal of bpy was enhanced by the Ag-NP embedded in the novel niobium phosphate substrate, allowing the detection at the concentration of 10–6 M. • Niobium phosphate containing Ag-NP on their surface is a useful sensor substrate for SERS applications. Abstract Surface-enhanced Raman scattering (SERS) is one of the most sensitive methods for the detection of adsorbed molecules on the nanostructured coinage-metal surface. The enhancements in the order of 104–106 are routinely observed. Such an effect makes SERS spectroscopy a technique applicable to the study the adsorption of analytes in the submonolayer regime. Novel SERS sensors require novel substrates with high activity for great sensibility detection of different molecules applied in many fields, such as detections of narcotics, explosives, and molecules with biological interest. In this work, silver nanoparticles embedded in niobium lead-pyrophosphate glasses (Pb 2 P 2 O 7 -Nb 2 O 5 -Na 2 O) were prepared by ion exchange process, where silver ions were introduced into glass surface by Ag+/Na+ ion exchange (NaNO 3 :AgNO 3 batch), and reduced to metallic silver by heat treatment at glass transition temperature (ca. 480 °C). The new substrate was characterized by Raman spectroscopy, optical absorption, transmission electron microscopy (TEM) and atomic force microscopy (AFM). Its application in SERS was demonstrated by studying the adsorption of 2,2-bipyridine (bpy) on the glass surface, which has marker bands for the coordination of the adsorbate with silver atoms. The optimal surface features in terms of SERS enhancement were also discussed and the sensing ability of this new substrate was demonstrated. [ABSTRACT FROM AUTHOR] more...

Different samples of cellulosic materials were analyzed by Raman spectroscopy and wood chips from Pinus elliottii , treated with acidic and alkaline aqueous solutions, were used to evaluate diagnostic signatures of the chemical structure of the cellulosic fibres. Cotton and whiskers synthesized from cotton, ancient Egyptian linen from a mummy wrapping, and five different paper sheets used in museum handling were compared. The complementarity of the Raman spectroscopic and scanning electron microscopic data facilitated the evaluation of the crystallinity, the level of organization and chain sizes of the fibres and the identification of different oxidation products. Intensity ratios measured from pairs of key bands were used to characterize the crystallinity, chain lengths and presence of oxidative decomposition in the range of the studied samples. Finally, the Raman spectra of the ancient Egyptian linen specimen indicated a potential future application of the proposed analysis for the characterization of archaeological pieces composed of linen. [ABSTRACT FROM AUTHOR] more...

In this work the adsorption of the antibiotics levofloxacin (LV), tetracycline (TC) and benzylpenicillin (BP) on the surface of silver nanoparticles (AgNP) have been investigated through both surface-enhanced Raman scattering (SERS) and UV–VIS–NIR spectroscopies. The SERS spectra were obtained using 1064 nm exciting radiation. Theoretical models for the antibiotic molecules were obtained from DFT calculations, and used in the vibrational assignment. The adsorption geometries were proposed based on the changes in the spectral patterns. The LV compound adsorbs through carboxylate group, TC compound interacts with silver atoms through carbonyl from intermediate ring, and BP compound adsorbs by carbonyl moieties from carboxylate and acyclic amide. [ABSTRACT FROM AUTHOR] more...

Specimens of neotropical Anopheles (Nyssorhynchus) were collected and identified morphologically. We amplified three genes for phylogenetic analysis–the single copy nuclear white and CAD genes, and the COI barcode region. Since we had multiple specimens for most species we were able to test how well the single or combined genes were able to corroborate morphologically defined species by placing the species into exclusive groups. We found that single genes, including the COI barcode region, were poor at confirming species, but that the three genes combined were able to do so much better. This has implications for species identification, species delimitation, and species discovery, and we caution that single genes are not enough. Higher level groupings were partially resolved with some well-supported groupings, whereas others were found to be either polyphyletic or paraphyletic. There were examples of known groups, such as the Myzorhynchella Section, which were poorly supported with single genes but were well supported with combined genes. From this we can infer that more sequence data will be needed in order to show more higher-level groupings with good support. We got unambiguously good support (0.94–1.0 Bayesian posterior probability) from all DNA-based analyses for a grouping of An. dunhami with An. nuneztovari and An. goeldii, and because of this and because of morphological similarities we propose that An. dunhami be included in the Nuneztovari Complex. We obtained phylogenetic corroboration for new species which had been recognised by morphological differences; these will need to be formally described and named. [ABSTRACT FROM AUTHOR] more...

[Display omitted] • Au nanoparticles modified with antibody, carrying rifampicin to infected macrophages. • Antibiotic drug delivery led to the combat of BCG bacteria infecting macrophages. • The uptake of gold nanocarrier in macrophage was monitored by SERS spectroscopy. • Anti-folic acid was anchored on gold surface bonding to previous adsorbed folic acid. • Antibody modifying gold surface interacted with macrophages by non-specific portions. Gold nanoparticles (AuNP) modified with antibody and rifampicin (RP) were tested against Mycobacterium bovis Bacillus Calmette-Guérin (BCG), which previously generated in vitro infection of macrophages from mice. Such a drug delivery system works as nanocarrier for RP and presented lower toxicity for macrophages cells than each separated component. Surface-enhanced Raman scattering (SERS) spectroscopy and fluorescence microscopy were used as analytical tools for the characterization of the internalization of gold nanocarriers into macrophage cells. The effective antibiotic action of RP, when combined with gold nanocarrier, was confirmed by dead-live assay of BCG bacteria lysed from macrophages after incubation. Such results indicate the delivery of RP to BCG bacteria, which were infecting macrophages, occurred with remarkable efficiency. It was rationalized based on the strategy used for the adsorption of antibody molecules on gold surface. [ABSTRACT FROM AUTHOR] more...