1,065 research outputs found
Evaluating the research productivity of a state university in Central Luzon, Philippines: Basis for policy recommendations
This descriptive study evaluated the research productivity of a state university in Central Luzon, Philippines, for the past five years (2016-2020) as basis for policy formulation. The study used document analysis to ascertain the research productivity in terms of: i) Number of papers published in refereed international journals such as Scopus and Commission on Higher Education (CHED) accredited journals; ii) Number of faculty researchers with publication to these journals; and iii) Total number of citations. The data were obtained primarily from online publications found in the Google Scholar and Scopus databases. Results revealed that the state university's research productivity is relatively high in terms of published papers in refereed international journals for the past five years. However, the published papers in Scopus-indexed journals and CHED accredited journals are relatively low. An average number of faculty researchers publish their works in reputable journals, but very few faculties publish in the journals recommended by the CHED. Likewise, the university had a remarkable research citation record for the past five years. The findings of this research have important implications for policy to improve research productivity and enhance the research culture in higher education institutions (HEIs). Such policies include the need to have strong support to faculty researchers, forge research collaborations, source external research funding, and establish a sound incentive mechanism
Multivariable control strategy for a bucket wheel reclaimer / Estratégia de controle multivariável de retomadora de roda de alcatruzes
Mining operations are generally done by large machines working in very harsh environments and historically having shy embedded technology. The use of control strategies, in many cases, dramatically increases the operating efficiency without large financial investments. In this context, this paper presents the method of choice and practical application of a multivariable control strategy for a bucket wheel ore reclaimer. This strategy adopts PI and PID controllers following a type override strategy acting on the manipulated variable: the slewing angular velocity. This manipulated variable was chosen because its actions affect the controlled variable very fast, so, allowing correcting disturbances in an adequate time. In addition, a fuzzy type controller was implemented to act on a second manipulated variable: the translation step. The second manipulated variable aims at taking the first one (angular speed) out of saturation states. When working together, these controllers seek to increase the equipment and process performance, taking into account, however, their operating limitations. Finally, a statistical analysis of results was performed in order to validate the feasibility of the implanted strategy when compared with the method previously in operation
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Unsupported trimetallic Ni(Co)-Mo-W sulphide catalysts prepared from mixed oxides: characterisation and catalytic tests for simultaneous tetralin HDA and dibenzothiophene HDS reactions
Unsupported A-Mo-W (A = Ni or Co) sulphide catalysts were obtained from mixed oxides containing different W:Mo ratios. An in situ liquid-phase sulphidation of the mixed oxides in a batch reactor was followed by catalytic tests in a liquid-phase reaction (at 613 K and 70 bar), using a mixture of dibenzotiophene (DBT) and tetralin (THN) as the feed. After the catalytic tests, the bulk sulphide catalysts were characterised by nitrogen physical adsorption, XANES/EXAFS, SEM and HR-(S)TEM. The HR-TEM images showed randomly oriented, stacked-layer particles typical of Mo (W) sulphides and an elemental HR-STEM mapping evidenced Mo/W homogeneous distribution in the trimetallic sulphides. The EXAFS results for the trimetallic catalysts are consistent with the presence of nickel or cobalt sulphide domains, and Mo1-xWxS2 solid solutions. The intralayer Mo:W solid solutions were confirmed to be thermodynamically stable with respect to phase separation by DFT calculations, which were also used to aid in the interpretation of the EXAFS results. The effect of the W:Mo ratio on the catalytic properties of the Ni- and Co-containing series was found to be different. For the Ni series, increasing the W content caused an activity increase in THN hydrodearomatization (HDA) relative to DBT hydrodesulphurization (HDS), while it had little influence on the relative contribution of the direct desulphurisation (DDS) route with respect to the previous hydrogenation (HYD) route for DBT HDS. In contrast, for the Co series, the activities and selectivities were essentially insensitive to the W content. Both the Ni and Co series of unsupported sulphides were more selective for the HYD route in DBT HDS than a supported NiMo/Al2O3 catalyst
Parâmetros biomecânicos derivados da forma da curva do ORA para discriminar olhos normais de ceratocones
PURPOSE: To evaluate the ability of the Ocular Response Analyzer (ORA; Reichert Ophthalmic Instruments, Buffalo, NY) to distinguish between normal and keratoconic eyes, by comparing pressure and waveform signal-derived parameters. METHODS: This retrospective comparative case series study included 112 patients with normal corneas and 41 patients with bilateral keratoconic eyes. One eye from each subject was randomly selected for analysis. Keratoconus diagnosis was based on clinical examinations, including Placido disk-based corneal topography and rotating Scheimpflug corneal tomography. Data from the ORA best waveform score (WS) measurements were extracted using ORA software. Corneal hysteresis (CH), corneal resistance factor (CRF), Goldman-correlated intraocular pressure (IOPg), cornea-compensated intraocular pressure (IOPcc), and 37 parameters derived from the waveform signal were analyzed. Differences in the distributions among the groups were assessed using the Mann-Whitney test. Receiver operating characteristic (ROC) curves were calculated. RESULTS: Statistically significant differences between keratoconic and normal eyes were found in all parameters (p<0.05) except IOPcc and W1. The area under the ROC curve (AUROC) was greater than 0.85 for 11 parameters, including CH (0.852) and CRF (0.895). The parameters related to the area under the waveform peak during the second and first applanations (p2area and p1area) had the best performances, with AUROCs of 0.939 and 0.929, respectively. The AUROCs for CRF, p2area, and p1area were significantly greater than that for CH. CONCLUSION: There are significant differences in biomechanical metrics between normal and keratoconic eyes. Compared with the pressure-derived parameters, corneal hysteresis and corneal resistance factor, novel waveform-derived ORA parameters provide better identification of keratoconus.OBJETIVO: Avaliar a capacidade do Ocular Response Analyzer (ORA; Reichert Ophthalmic Instruments, Buffalo, NY) em discriminar olhos com ceratocone de olhos normais e comparar parâmetros derivados da pressão dos parâmetros derivados da forma da curva. MÉTODOS:Estudo comparativo retrospectivo série de casos que incluiu 112 pacientes com olhos normais e 41 pacientes com ceratocone bilateral. Um olho de cada indivíduo foi randomicamente selecionado para análise. O diagnóstico de ceratocone foi baseado em exame clínico, incluindo topografia de Plácido e tomografia Scheimpflug. Informação do melhor waveform score foi extraída do software do ORA. Histerese corneana (CH), fator de resistência corneana (CRF), pressão intraocular correlacionada com Goldman (IOPg), pressão intraocular compensada pela córnea (IOPcc) e 37 novos parâmetros derivados da forma da curva do sinal do ORA foram analisados. Diferenças nas distribuições dos grupos foram avaliadas pelo teste Mann-Whitney. Curvas ROC foram calculadas. RESULTADOS: Diferenças estatisticamente significantes foram encontradas entre os olhos normais e ceratocones em todos os parâmetros (p<0,05) salvo IOPcc e W1. A área sob a curva ROC (AUROC) foi maior que 0.85 em 11 parâmetros, incluindo CH (0,852) a CRF (0,895). Os parâmetros relacionados com a área sob o pico da forma de onda durante a segunda e primeira aplanação (p2area e p1area) obtiveram as melhores performances, com AUROCs de 0,939 e 0,929, respectivamente. Os valores de AUROCs do fator de resistência corneana, p2area e p1area foram significativamente maiores que os valores de histerese corneana. CONCLUSÃO: Existem diferenças significantes nas medidas biomecânicas entre olhos normais e com ceratocone. Comparados com os parâmetros derivados da pressão, histerese corneana e fator de resistência corneana, os parâmetros derivados da forma da curva proporcionaram melhor identificação dos ceratocones.Universidade Federal de São Paulo (UNIFESP) Department for OphthalmologyHospital de Olhos de SergipeInstituto de Olhos Renato AmbrósioUNIFESP, Department for OphthalmologySciEL
Procjena produktivnosti bioreaktora Zymotis sa čvrstim slojem zasnovana na ukupnom volumenu reaktora
In this work a method of analyzing the performance of solid-state fermentation bioreactors is described. The method is used to investigate the optimal value for the spacing between the cooling plates of the Zymotis bioreactor, using simulated fermentation data supplied by a mathematical model. The Zymotis bioreactor has good potential for those solid-state fermentation processes in which the substrate bed must remain static. The current work addresses two design parameters introduced by the presence of the internal heat transfer plates: the width of the heat transfer plate, which is governed by the amount of heat to be removed and the pressure drop of the cooling water, and the spacing between these heat transfer plates. In order to analyze the performance of the bioreactor a productivity term is introduced that takes into account the volume occupied within the bioreactor by the heat transfer plates. As part of this analysis, it is shown that, for logistic growth kinetics, the time at which the biomass reaches 90 % of its maximum possible value is a good estimate of the optimum harvesting time for maximizing productivity. Application of the productivity analysis to the simulated fermentation results suggests that, with typical fast growing fungi ( = 0.324 h–1), the optimal spacing between heat transfer plates is of the order of 6 cm. The general applicability of this approach to evaluate the productivity of solid-state bioreactors is demonstrated.Opisana je metoda analize rada fermentacijskog bioreaktora sa čvrstim slojem. Postupak je primijenjen da bi se ispitala optimalna vrijednost za razmak između ploča za hlađenje u bioreaktoru Zymotis, koristeći simulirane fermentacijske podatke dobivene prema matematičkom modelu. Bioreaktor Zymotis je vrlo prikladan za one fermentacijske procese u čvrstom sloju u kojima supstratni sloj mora ostati statičan. Opisani postupak koristi dva određena parametra uvjetovana prisutnošću internih ploča za prijenos topline. Širina ploča za prijenos topline uvjetovana je količinom topline koju treba uklonitii padom tlaka rashladne vode te razmakom između tih ploča. Da bi se analizirao učinak bioreaktora, uveden je pojam produktivnosti koji uzima u obzir volumen unutar bioreaktora što ga zauzimaju ploče za prijenos topline. Kao dio ove analize pokazalo se da je, prema logistici kinetike rasta, optimalno vrijeme za povećavanje produktivnosti upravo ono kada biomasa postiže 90 % svoje maksimalne moguće vrijednosti
Efeito do tamanho de gotas de iscas tóxicas na mortalidade de adultos da mosca-das-frutas sul-americana.
Neste trabalho foi avaliado o efeito do tamanho de gotas de uma isca tóxica formulada com o atrativo alimentar ANAMED® e o inseticida Malathion 1000 EC (0,2% v/v) na mortalidade de adultos de A. fraterculus em laboratório
Treatment of exudative age-related macular degeneration with intravitreal ranibizumab in clinical practice: a 3-year follow-up
PURPOSE:
To evaluate the 36-month efficacy of intravitreal ranibizumab injections for choroidal neovascularization secondary to age-related macular degeneration (AMD) in real world clinical practice.
METHODS:
Retrospective study involving 84 eyes of 77 patients; 52 eyes completed 3 years of follow-up. Subjects were observed initially on a monthly basis and with extended follow-up intervals if signs of quiescence were detected, according to an established protocol. A comprehensive ophthalmologic examination was performed, including best-corrected visual acuity (BCVA) determined with Early Treatment Diabetic Retinopathy Study charts, stereoscopic macular biomicroscopy and optical coherence tomography (OCT) with fluorescein angiography and indocyanine green angiography if considered necessary. Treatment was given if signs of active lesions were present.
RESULTS:
The mean baseline BCVA was 49.33 and 49.52 letters at the 36-month visit. The average of treatments was 8.6 at 3 years. At this time point, 77% of treated eyes stabilized or improved their vision (VA loss ≤ 5 letters). A predictive value for better VA was found for younger age, better baseline VA, good response on OCT and more frequent treatments.
CONCLUSION:
At 3 years, intravitreal ranibizumab is able to maintain baseline VA in exudative AMD patients, with a reduced number of injections, but not to show VA improvement, in clinical practice.info:eu-repo/semantics/publishedVersio
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