4,138 research outputs found

    Investigating students understanding of organic reaction mechanisms from performing organic chemistry experiments

    Get PDF
    The use of laboratory work to improve students’ knowledge of theory is one that is disputed. Student reflections of what they learn during practical work repeatedly show that students rarely think about theory. There is a lack of data that objectively compares students’ knowledge of theory where they complete an associated experiment to when they do not in order to understand if practical work does effect students’ knowledge of scientific concepts. In this work we aimed to address this gap by investigating the effect of students’ knowledge of organic mechanisms where they both perform and associated experiment and where they did not. Our results showed that organic chemistry experiments had no effect on students’ knowledge of organic mechanisms. These results support the view that there is little evidence to support the use of laboratory work to aid understanding of theory

    Novel Method of Measuring Electron Positron Colliding Beam Parameters

    Get PDF
    Through the simultaneous measurement of the transverse size as a function of longitudinal position, and the longitudinal distribution of luminosity, we are able to measure the βy∗\beta_y^\ast (vertical envelope function at the collision point), vertical emittance, and bunch length of colliding beams at the Cornell Electron-positron Storage Ring (CESR). This measurement is possible due to the significant ``hourglass'' effect at CESR and the excellent tracking resolution of the CLEO detector.Comment: 11 pages, 4 figures, submitted to NIM

    dRail: a novel physical layout methodology for power gated circuits

    No full text
    In this paper we present a physical layout methodology, called dRail, to allow power gated and non-power gated cells to be placed next to each other. This is unlike traditional voltage area layout which separates cells to prevent shorting of power supplies leading to impact on area, routing and power. To implement dRail, a modified standard cell architecture and physical layout is proposed. The methodology is validated by implementing power gating on the data engine in an ARM Cortex-A5 processor using a 65nm library, and shows up to 38% reduction in area cost when compared to traditional voltage area layou

    A REVIEW ON BIOACTIVE PHYTOCHEMICALS AND IT’S MECHANISM ON CANCER TREATMENT AND PREVENTION BY TARGETING MULTIPLE CELLULAR SIGNALING PATHWAYS

    Get PDF
    In developing and developed countries, cancer is a significant health problem in people. Cancer becomes the second greatest cause of death in human after cardiovascular disease. However, significant advancements in modern cancer therapies have a beneficial impact on survival, chemotherapy and radiation therapy. Plants fulfill our basic needs to continue life and provide natural products that help to cure disease. The medicinal plants are readily available and have no toxicity as compared to modern drugs. Phytochemicals act on metabolic pathways and inhibit tumor growth, the development of cancerous cells, and replication by different mechanisms. Apigenin's chemo-preventive and anticancer activities have been demonstrating in numerous studies. Curcumin is a polyphenolic compound isolated from the Curcuma longa plant. EGCG, a polyphenol in black, white, and green tea is a chemo-preventive effect against many cancers by targeting multiple pathways. Normal cell growth and cell proliferation are closely regulated processes. The JAK-STAT (Janus kinase-signal transducer and activator of transcription) pathway controls gene expression during different processes, including proliferation, initiation, and apoptosis. The transcription factors are associated with the growth of cancer cells and control a cellular function in the disease. Mitogen-activated protein kinase (MAPK) is a class of serine and threonine kinase that includes ERK (extracellular regulated kinase), JNK (c-Jun N-terminal kinases), and p38. This review paper describes natural phytochemical compounds, their molecular targets and mechanisms of action

    Lower limb cellulitis: low diagnostic accuracy and underdiagnosis of risk factors

    Get PDF
    Accurate diagnosis and recognition of predisposing factors has been shown to be challenging in lower limb cellulitis. Assessment of 1746 consecutive cellulitis patients presenting to a UK university hospital showed increasing overdiagnosis with only 31.9% of referred patients with confirmed lower-limb cellulitis between 2015-2018. Recognition of at least one predisposing factor increased from 61% to 89% following introduction of more specific screening questions. This identified a need for better primary care dermatology education and the benefit of a proforma with specific screening questions for reversible predisposing factors for lower limb cellulitis. This article is protected by copyright. All rights reserved
    • …
    corecore