A Roadmap to Transform Learning From Face-to-Face to Online

Online learning offers a flexible learning environment, allowing colleges to attain a global presence and provide a higher caliber of student learning experiences. The implementation of online learning, however at the educational institution can lead to various challenges across three main clusters: students, faculty, and management. An overview of these challenges, based on the review of the current literature, is provided in this paper along with appropriate mitigation strategies. A generalized roadmap is established in this article that illustrates how the transition from face-to-face to online courses can be managed using a series of key steps in three critical phases during online course development: prior to, during, and post course development. The roadmap is applicable to educational institutions interested in starting their online learning journey and can provide additional guidance to institutions with an already established online presence. It facilitates the creation of well-structured online courses for students, ensures faculty are enrolled in professional development activities that support delivery of online courses, and supports managers in developing effective plans to implement technology infrastructure and create policies to support successful online learning

Developmental stages and viability of Toxocara canis eggs outside the host

Introduction: Toxocariasis is a soil-transmitted zoonotic disease caused mainly by ingestion of larvated eggs of Toxocara canis. Objectives: To study the morphology of the intraovular developmental stages of Toxocara canis in culture, characterize non-viable eggs and the sequences of larval molting and compare the viability of eggs at the early stages of division and at reaching full maturation. Material and methods: Observation of developing embryos and characterization of non-viable eggs were done using light microscope. The proportions of viable eggs during embryonation were compared to the proportions of viable mature eggs. Results: Cell division commenced after 24 hours of cultivation. Early stages were found to be present over a period of 3-5 days. The developmental stages identified were eggs with: One cell, two cells, three cells, four cells, early morula, late morula, blastula, gastrula, tadpole, pre-larva, first, second and third stage larva. Two larval molts occurred. Non-viable eggs had degenerated cytoplasm, thin or collapsed shell and the larvae did not move after exposure to light. No significant differences were found between the proportions of viable eggs from day five to day 21 as compared to viability of fully mature eggs (30 days). Conclusion: Developing embryos in the environment may be considered as a potential threat to the public health. The precise identification of developmental stages and the clear differentiation of viable and non-viable eggs can help in determining an accurate baseline rate of development that could be used in studies of ovicidal compounds

The Evolution of Dynamical Screening in the Parton Cacade Model

We determine the time evolution of the colour screening mass in high energy nuclear collisions, as provided by the parton cascade model. Using our result, we discuss the onset of deconfinement and the onset of quarkonium suppression in a general, not necessarily equilibrated environment of strongly interacting constituents.Comment: 11 pages, including 4 figure

Efectividad in vitro de tres fármacos aprobados y su interacción sinérgica contra Leishmania infantum

Introduction: Leishmaniasis remains one of the neglected tropical diseases. Repurposing existing drugs has proven to be successful for treating neglected tropical diseases while combination therapy is a strategic alternative for the treatment of infectious diseases.Auranofin, lopinavir/ritonavir, and sorafenib are FDA approved drugs used in the treatment of diverse diseases by acting on different essential biological enzymes.Objective: To evaluate the effects of monotherapy and combined therapies with the three drugs against Leishmania infantum.Materials and methods: We compared the leishmanicidal effects of the three drugs on promastigotes in vitro as regards the parasite count, the drug concentration providing a half-maximal response, and the ultrastructural changes of the parasite. We determined the fractional inhibitory concentration index of combined drugs in two ways, as well as the activity of the three drugs together to establish their synergetic effect.Results: The monotherapy with the three drugs was effective with auranofin showing the best leishmanicidal effect (EC50=1.5 μM), whereas sorafinib reduced parasite growth at EC50=2.5 μM. The scanning electron microscopy of promastigotes from all treated media showed distortion in the shape with loss of flagella and bleb formation. Acidocalcinosis was evident by transmission electron microscopy with all treatments suggesting apoptosis. Treatment with lopinavir/ritonavir showed signs of autophagy. The two-way combination of the drugs led to additive interactions while the combination of the three drugs showed synergistic action.Conclusion: Each drug when used as monotherapy against Leishmania spp. was effective, but the combination therapy was more effective than the individual drugs due to the additive or synergistic effects.Introducción. La leishmaniasis sigue siendo una de las enfermedades tropicales desatendidas. La reutilización de medicamentos existentes ha demostrado ser exitosa para tratar enfermedades tropicales desatendidas y la terapia combinada es una alternativa estratégica para el tratamiento de enfermedades infecciosas. Auranofin, lopinavir/ritonavir y sorafenib son medicamentos aprobados por la Food and Drug Administration (FDA) de Estados Unidos utilizados en el tratamiento de diversas enfermedades, pues actúan sobre diferentes enzimas biológicas esenciales.Objetivo. Evaluar los efectos terapéuticos de la monoterapia y de los tres fármacos combinados contra Leishmania infantum.Materiales y métodos. Los efectos leishmanicidas de los tres fármacos sobre los promastigotes se compararon in vitro en cuanto al recuento de parásitos, la concentración del fármaco que proporcionara una respuesta semimáxima y los cambios ultraestructurales del parásito. Se calculó el índice de concentración inhibitoria de fracciones de fármacos combinados de dos maneras y la actividad de los tres fármacos juntos para determinar el efecto sinérgico.Resultados. La monoterapia con los tres medicamentos fue efectiva, pero la auranofina tuvo el mejor efecto antileishmanicida con un CE50 de 1,5 μM, en tanto que el sorafinib redujo el crecimiento del parásito con un CE50 de 2,5 μM. La microscopía electrónica de barrido de promastigotes de todos los medios tratados mostró una distorsión en la forma, con pérdida de flagelos y formación de ampollas. La acidocalcinosis fue evidente por microscopía electrónica de transmisión con todos los tratamientos, lo que sugiere apoptosis. El tratamiento con lopinavir/ritonavir mostró signos de autofagia. La combinación de dos medicamentos condujo a interacciones aditivas, mientras que la combinación de las tres drogas produjo una acción sinérgica.Conclusión. Los tres medicamentos usados como monoterapia contra Leishmania spp. fueron efectivos, pero el tratamiento combinado lo fue en mayor medida debido a los efectos aditivos o sinérgicos

Perception of Biostatistics by Lebanese Medical Students: A Cross-Sectional Study

Background: Inadequate use of statistics in biomedical research might not only affect science but also harm human beings if applied in medical practice. Biostatistics is fundamental to improve understanding and appraising of evidence-based medicine (EBM); yet, it is still not well understood and appreciated by medical students. Therefore, early exposure of medical students and physicians-in-training to research tools including Biostatistics is of utmostimportance.Objective: The aim of this study is to determine the perception of Biostatistics by medical students at a private medical school in Beirut, Lebanon, and to identify its best implementation time in the medical curriculum.Methods: This is a cross-sectional study based on a self-administered questionnaire distributed among medical students in their pre-clerkship years (first three years of a 6-year program) who undertook Biostatistics. The assessment of perception was based on the 5-point Likert scale anchored by Strongly disagree = 1 and Strongly agree = 5 including 36 questions distributed into four domains to assess the course value, difficulty, behavioral, and expectations.Results: 186 of 269 students responded to the questionnaire, yielding a response rate of 69.14%. Around 60% of students declared that the knowledge gained from biostatistics courses is useful to their future career, and almost 70% understood the main concepts of biostatistics. 57.7% of students perceived that lack of practicing exercises might contribute to making the course more difficult. The mean score of domains was higher in females but did not significantly differ within the three academic years. Only 35.1% of the students positively perceived the importance of biostatistics modules, mostly third-year students.Conclusion: Although the majority of medical students perceived biostatistics modules negatively, they were aware of the relevance of biostatistics to their medical career and real-life health issues

Niosomas encapsulados en praziquantel contra Schistosoma mansoni con sensibilidad reducida al praziquantel

Introduction: Praziquantel (PZQ) is the only commercially available drug for schistosomiasis. The current shortage of alternative effective drugs and the lack of successful preventive measures enhance its value. The increase in the prevalence of PZQ resistance under sustained drug pressure is, therefore, an upcoming issue. Objectives: To overcome the tolerance to PZQ using nanotechnology after laboratory induction of a Schistosoma mansoni (S. mansoni) isolate with reduced sensitivity to the drug during the intramolluscan phase. Materials and methods: Shedding snails were treated with PZQ doses of 200 mg/kg twice/week, followed by an interval of one week, and then repeated twice in the same manner. The success of inducing reduced sensitivity was confirmed in vitro via the reduction of cercarial response to PZQ regarding their swimming activity and death percentage at different examination times. Results: Oral treatment with a single PZQ dose of 500 mg/kg in mice infected with cercariae with reduced sensitivity to PZQ revealed a non-significant reduction (35.1%) of total worm burden compared to non-treated control mice. Orally inoculated PZQ-encapsulated niosomes against S. mansoni with reduced sensitivity to PZQ successfully regained the pathogen’s sensitivity to PZQ, as evidenced by measuring different parameters in comparison to the non-treated infected animals with parasites with reduced sensitivity to PZQ. The mean total worm load was 1.33 ± 0.52 with a statistically significant reduction of 94.09% and complete eradication of male worms. A remarkable increase in the percentage reduction of tissue egg counts in the liver and intestine (97.68% and 98.56% respectively) was obtained associated with a massive increase in dead eggs and complete absence of immature stages. Conclusion: PZQ-encapsulated niosomes restored the drug sensitivity against laboratory-induced S. mansoni adult worms with reduced sensitivity to PZQ.Introducción. El praziquantel (PZQ) es el único fármaco disponible comercialmente para la esquistosomiasis. La escasez actual de medicamentos alternativos eficaces y la falta de medidas preventivas eficaces aumentan su valor. El aumento de la prevalencia de la resistencia al PZQ bajo una presión prolongada del fármaco es, por tanto, un tema emergente. Objetivos. Superar la tolerancia a PZQ mediante nanotecnología después de la inducción en laboratorio de un aislamiento de Schistosoma mansoni (S. mansoni) con sensibilidad reducida al fármaco durante la fase intramolusca. Material y métodos. Los caracoles que liberaban cercarias se trataron con dosis de PZQ de 200 mg / kg dos veces por semana, seguido de un intervalo de una semana, y luego se repitieron dos veces de la misma manera. El éxito de inducir una sensibilidad reducida se confirmó in vitro mediante la reducción de la respuesta de las cercarias al PZQ con respecto a su actividad de natación y el porcentaje de muerte en diferentes momentos de examen. Resultados. El tratamiento oral con una dosis única de PZQ de 500 mg / kg en ratones infectados con cercarias con sensibilidad reducida a PZQ reveló una reducción no significativa (35,1%) de la carga total de gusanos en comparación con los ratones de control no tratados. Los niosomas encapsulados en PZQ inoculados por vía oral contra S. mansoni con sensibilidad reducida a PZQ permitieron reestablecer con éxito la sensibilidad del patógeno a PZQ, como lo demuestra la medición de diferentes parámetros en comparación con los animales infectados no tratados con parásitos con sensibilidad reducida a PZQ. La carga media total de gusanos fue de 1,33 ± 0,52 con una reducción estadísticamente significativa del 94,09% y la erradicación completa de los gusanos machos adultos. Se obtuvo un aumento notable en el porcentaje de reducción del recuento de huevos en tejido en el hígado y el intestino (97,68% y 98,56% respectivamente) asociado con un aumento masivo de huevos muertos y ausencia total de estadios inmaduros. Conclusión. Los niosomas encapsulados en PZQ restauraron la sensibilidad al fármaco contra gusanos adultos de S. mansoni inducidos en laboratorio con sensibilidad reducida a PZQ

Parton rescattering and screening in Au+Au collisions at RHIC

We study the microscopic dynamics of quarks and gluons in relativistic heavy ion collisions in the framework of the Parton Cascade Model. We use lowest order perturbative QCD cross sections with fixed lower momentum cutoff p_0. We calculate the time-evolution of the Debye-screening mass for Au+Au collisions at sqrt(s)=200 GeV per nucleon pair. The screening mass is used to determine a lower limit for the allowed range of p_0. We also determine the energy density reached through hard and semi-hard processes at RHIC, obtain a lower bound for the rapidity density of charged hadrons produced by semihard interactions, and analyze the extent of perturbative rescattering among partons.Comment: 6 pages, 4 figures, uses RevTeX 4.0; revised version with minor corrections and one updated figur

A Poincare-Covariant Parton Cascade Model for Ultrarelativistic Heavy-Ion Reactions

We present a new cascade-type microscopic simulation of nucleus-nucleus collisions at RHIC energies. The basic elements are partons (quarks and gluons) moving in 8N-dimensional phase space according to Poincare-covariant dynamics. The parton-parton scattering cross sections used in the model are computed within perturbative QCD in the tree-level approximation. The Q^2 dependence of the structure functions is included by an implementation of the DGLAP mechanism suitable for a cascade, so that the number of partons is not static, but varies in space and time as the collision of two nuclei evolves. The resulting parton distributions are presented, and meaningful comparisons with experimental data are discussed.Comment: 30 pages. 11 figures. Submitted to Phys.Rev.

Parton Equilibration in Relativistic Heavy Ion Collisions

We investigate the processes leading to phase-space equilibration of parton distributions in nuclear interactions at collider energies. We derive a set of rate equations describing the chemical equilibration of gluons and quarks including medium effects on the relevant QCD transport coefficients, and discuss their consequences for parton equilibration in heavy ion collisions.Comment: 18 pages, 6 Figures appended as uuencoded PostScript files, (no changes in the previously submitted manuscript), DUKE-TH-93-4

Influence of 'Trichobilharzia regenti' (Digenea: Schistosomatidae) on the defence activity of 'Radix lagotis' (Lymnaeidae) haemocytes

Radix lagotis is an intermediate snail host of the nasal bird schistosome Trichobilharzia regenti. Changes in defence responses in infected snails that might be related to host-parasite compatibility are not known. This study therefore aimed to characterize R. lagotis haemocyte defence mechanisms and determine the extent to which they are modulated by T. regenti. Histological observations of R. lagotis infected with T. regenti revealed that early phases of infection were accompanied by haemocyte accumulation around the developing larvae 2–36 h post exposure (p.e.) to the parasite. At later time points, 44–92 h p.e., no haemocytes were observed around T. regenti. Additionally, microtubular aggregates likely corresponding to phagocytosed ciliary plates of T. regenti miracidia were observed within haemocytes by use of transmission electron microscopy. When the infection was in the patent phase, haemocyte phagocytic activity and hydrogen peroxide production were significantly reduced in infected R. lagotis when compared to uninfected counterparts, whereas haemocyte abundance increased in infected snails. At a molecular level, protein kinase C (PKC) and extracellular-signal regulated kinase (ERK) were found to play an important role in regulating these defence reactions in R. lagotis. Moreover, haemocytes from snails with patent infection displayed lower PKC and ERK activity in cell adhesion assays when compared to those from uninfected snails, which may therefore be related to the reduced defence activities of these cells. These data provide the first integrated insight into the immunobiology of R. lagotis and demonstrate modulation of haemocyte-mediated responses in patent T. regenti infected snails. Given that immunomodulation occurs during patency, interference of snail-host defence by T. regenti might be important for the sustained production and/or release of infective cercariae