1,965 research outputs found

    Fluorinated Epoxy Resins-based Sorbent Coating Materials for Quartz Piezoelectric Crystal Detector

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    Fluorinated epoxy resins were synthesised and evaluated as sorbent coating materials for the detection of organophosphorus compounds using quartz piezoelectric crystal detector. These resins were prepared by reacting excess of epichlorohydrin with each of or in combination of fluorinated diols, ie, a, a, a', a' tetrakis (trifluoromethyl) 1,3 benzene dimethanol (TTFMBD), 4,4'bis-2-hydroxy hexafluoro isopropyl) biphenyl (BHHFIBP), 4,4'dihydroxyocta fluorodiphenyl (DHOFDP) and 2,2,3,3,4,4 hexafluoro 1,5 pentanediol (HFPD) in the presence of sodium hydroxide at reflux temperature. These polymers were extracted in organic solvents and dried. Each of these fluoroepoxy resins were coated over quartz piezoelectric crystal by solution-casting method and tested using dimethylmethyl phosphonate (DMMP) as model compound. Change in the  frequency (AF) of quartz piezoelectric crystal oscillator was recorded. Sensitive and potential fluorinated epoxy resins, ie, diglycidylethers (DGE) of HFPD-TTFMBD (in the molar ratio 6:4) and DGE (HFPD-BHHFIBP in the molar ratio 4:6) were characterised by viscosity, number average molecular weight (Mn), epoxy equivalent, infrared spectroscopy, and thermal stability

    ESTIMATION OF GUGGULSTERONE-Z IN GOKSHURADI GUGGULU USING REVERSED-PHASE HIGH-PERFORMANCE LIQUID CHROMATOGRAPHY

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    Objective: A study was aimed to estimate guggulsterone-Z (GZ) in Gokshuradi Guggulu (GG).Methods: An analytical method was developed and validated using Waters Alliance high-performance liquid chromatography system (Empower software), equipped with photodiode array detector. Separation was achieved using Phenomenex, C-18 (250 mm×4.6 mm, 5 ĂŽÂŒ) column. Mobile phase consisted of acetonitrile:water (70:30,v/v). Flow rate was set to 1 ml/min and detection was performed at 251 nm.Results and Discussion: Validation parameters such as linearity, precision, accuracy, limit of detection, limit of quantification, and robustness were performed. Amount of GZ was estimated using linearity equation.Conclusion: GG was found to contain 0.815±0.03 g% w/w GZ. Validated method may be used as one of the parameters to standardize the formulation

    Study on Miniaturized Dual Polarized MIMO Antenna

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    MIMO (Multiple input multiple output) used multiple transmit and receive antennas to utilize multipath propagation. This method is for multiplying the capacity of a radio link. In wireless communication standards MIMO has an essential element. “MIMO” refers to a practical technique used for sending and receiving more than one data signal via multipath propagation on the same radio channel at the same time. The demand of wireless communication increases due to miniaturized Antenna and dual polarization. Compactness in system is increased by miniaturization. Data propagation rate increased due to dual polarization by differentiating propagation polarization. In this work attempt will be to conduct elaborate Study, Design and Analysis of some of the Miniaturization techniques along with bandwidth enhancement and also on Dual polarization techniques. In future the techniques will be combined and study for Miniaturized Dual Polarized MIMO Antenna will be done

    Multivariate analysis of histopathological features as prognostic factors in fifty cases of thyroid neoplasm: a retrospective study done at tertiary care centre

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    Background: Number of prognostic factors for thyroid carcinoma have been identified including age, gender and tumor characteristics, such as histology and stage. The importance of these factors as independent predictors of survival for patients with differentiated thyroid carcinoma has been extensively studied but remains uncertain. Methods: A retrospective analysis of 50 thyroid carcinomas was made to assess prognostic factors including histological variants from September 2019 to February 2022 at our centre. The surgical and histopathological data were studied. Results: 72% patients had papillary thyroid cancer. Multivariate analysis was done and factors showing prognostic significance were tumour size, extrathyroid extension, extranodal extension, lymphovascular, perineural invasion, histological type, necrosis, focality, capsular invasion were found to have poor prognosis. Conclusions: There are histopathological factors which can modify the course and influence the line of treatment of thyroid neoplasms

    QUALITY MANAGEMENT PRACTICES AND COMPETITIVE ADVANTAGE OF SELECTED FOOD AND BEVERAGE MANUFACTURING FIRMS IN LAGOS STATE, NIGERIA

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    The performance of Food and Beverages manufacturing firms is important to the development of the economy and this has been considered by researchers. In Nigeria, the decline in the performance of this sector in terms of competitive advantage has been noticed which could be as a result of a lack of quality management practices such as leadership behaviour, strategic quality planning, supplier quality management, process management and customer focus. The study investigated the effect of quality management practices on the competitive advantage of selected Food and Beverages manufacturing firms in Lagos State, Nigeria. The survey research design was adopted. The population of the study was 14, 591 top, middle and low-level management employees of the selected Food and Beverages manufacturing firms in Lagos State, Nigeria. A sample size of 491 was determined using the research advisor table. A simple random sampling technique was used. A validated questionnaire was used to collect data. Cronbach’s alpha reliability coefficients for the constructs ranged from 0.866 to 0.954. The response rate was 100%. Data were statistically analysed using descriptive and inferential statistics (multiple and hierarchical regression). Findings revealed that quality management practices had a significant effect on the competitive advantage of Food and Beverages manufacturing firms in Lagos State, (Adj.R2 = 0.117; F (5, 485) = 14.025, p < 0.05). The study concluded that quality management practices affected competitive advantage in Food and Beverages manufacturing firms in Lagos State, Nigeria. The study recommends that Food and Beverages manufacturing firms should encourage the adoption of quality management practices to enhance competitive advantage.  Article visualizations

    Random matrix ensemble with random two-body interactions in presence of a mean-field for spin one boson systems

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    For mm number of bosons, carrying spin (SS=1) degree of freedom, in Ω\Omega number of single particle orbitals, each triply degenerate, we introduce and analyze embedded Gaussian orthogonal ensemble of random matrices generated by random two-body interactions that are spin (S) scalar [BEGOE(2)-S1S1]. The embedding algebra is U(3)⊃G⊃G1⊗SO(3)U(3) \supset G \supset G1 \otimes SO(3) with SO(3) generating spin SS. A method for constructing the ensembles in fixed-(mm, SS) space has been developed. Numerical calculations show that the form of the fixed-(mm, SS) density of states is close to Gaussian and level fluctuations follow GOE. Propagation formulas for the fixed-(mm, SS) space energy centroids and spectral variances are derived for a general one plus two-body Hamiltonian preserving spin. In addition to these, we also introduce two different pairing symmetry algebras in the space defined by BEGOE(2)-S1S1 and the structure of ground states is studied for each paring symmetry.Comment: 22 pages, 6 figure

    Great Expectations: The Role of Rules in Guiding Pro-social Behaviour in Groups with High Versus Low Autistic Traits

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    Measuring autistic traits in the general population has proven sensitive for examining cognition. The present study extended this to pro-social behaviour, investigating the influence of expectations to help others. A novel task describing characters in need of help was administered to students scoring high versus low on the Autism-Spectrum Quotient. Scenarios had two variants, describing either a 'clear-cut' or 'ambiguous' social rule. Participants with high versus low autistic traits were less pro-social and sympathetic overall towards the characters. The groups' ratings of characters' expectations were comparable, but those with high autistic traits provided more rule-based rationales in the clear-cut condition. This pattern of relatively intact knowledge in the context of reduced pro-social behaviour has implications for social skill training programmes

    Physicality and Cooperative Design

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    CSCW researchers have increasingly come to realize that material work setting and its population of artefacts play a crucial part in coordination of distributed or co-located work. This paper uses the notion of physicality as a basis to understand cooperative work. Using examples from an ongoing fieldwork on cooperative design practices, it provides a conceptual understanding of physicality and shows that material settings and co-worker’s working practices play an important role in understanding physicality of cooperative design

    Similarity in the restrictiveness of bond covenants

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    We examine the economic determinants and consequences associated with the inclusion of covenants with similar levels of restrictiveness in bond contracts. Using a unique Moody’s bond covenant dataset, we develop measures that capture similarity in the restrictiveness of bond covenants relative to previously issued peer bonds. We document that the demand for similarity by issuers, their advisors and bond investors follows the predictions of sociological and economic theories. Further, consistent with similarity in covenants reducing bond investors’ information acquisition and processing costs, we show that bonds with more similar covenant restrictiveness receive lower yields at issuance. These bonds are also more likely to be held by long-term bond investors, such as insurance companies, and are characterized by greater liquidity in the secondary market, providing a partial explanation for the lower bond yields. Our results highlight the benefits of covenant similarity and suggest that the use of covenants with similar restrictiveness levels brings information acquisition and processing cost savings that may be larger than the monitoring benefits provided by covenants with more tailored features
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