84 research outputs found

    Optimal design synthesis of multi speed gear trains

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    "To overcome the practical difficulty of repeated analyses of different design layouts of gear drive application, a new computer aided design methodology is proposed for generating all possible speed diagrams."--Cf. leaf iii

    Dosimetric study of SIB-IMRT versus SIB-3DCRT for breast cancer with breath-hold gated technique

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    Background and Purpose: 3-dimensional conformal therapy (3DCRT) is widely employed radiation therapy technique for breast cancer, but there is still need to minimize the doses to organ at risk (OAR) using 3DCRT. A few clinical studies have discussed using intensity modulated radiation therapy (IMRT) to address this shortfall. Simultaneous integrated boost (SIB) has been used in head and neck and prostate cancer, and there is a growing interest in using SIB for breast cancer too. This study aimed to compare SIB-IMRT versus SIB-3DCRT for breast cancer patients. Materials and Methods: SIB-3DCRT treatment plans were created for 36 consecutive patients. Dose was prescribed as 45 Gy in 25 fractions to the planning target volume (PTV)-1 and 60 Gy in 25 fractions to PTV-2. Treatment plans were normalized to 95% of PTV volume receiving 95% of the prescription dose. The conformity index (CI), homogeneity index (HI), lung dose, heart dose, left anterior descending artery(LAD) dose, and low dose volume and integral dose of normal healthy tissue were recorded and analyzed. Results: With the use of IMRT technique, there was an improvement in CI (0.14) when compared to CI of 3DCRT (0.18; p = 0.01). However, there was no significant difference in the HI (p = 0.45). On average, the V20Gy of ipsilateral lung was 37.9 % for 3DCRT and 22.4 % (p < 0.01) for IMRT, whereas the V20Gy of total lung (ipsilateral + contralateral) was 21.8% for 3DCRT and 12.14 (p < 0.01) for IMRT. Similarly, average V40Gy of heart was 7.5 % for 3DCRT and 2.13 % (p = 0.01) for IMRT. The LAD maximum dose to left side breast patients, on average, was 39.5 Gy for 3DCRT and 29.17 Gy (p = 0.03) for IMRT. The average number of monitor units was about 180 for 3DCRT and 1441 (p < 0.01) for IMRT. Conclusion: IMRT for breast cancer treatment is feasible. In comparison to 3DCRT, IMRT can reduce the maximum dose to the target volume, and dose to the OAR. However, 3DCRT technique is superior in terms of low dose volume, integral dose, and treatment time. With the use of breath-hold gated technique in IMRT, it can further improve the target coverage and reduction of doses to the heart, lung, and LAD. SIB technique could reduce the overall treatment duration by about one week.----------------------------------Cite this article as:Moorthy S, Sakr H, Hasan S, Samuel J, Al-Janahi S, Murthy N. Dosimetric study of SIB-IMRT versus SIB-3DCRT for breast cancer with breath-hold gated technique. Int J Cancer Ther Oncol 2013;1(1):010110. DOI: http://dx.doi.org/10.14319/ijcto.0101.1

    Study of forced degradation behaviour of eprosartan mesylate and development of validated stability indicating assay method by UPLC

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    The present research work describes comprehensive stress testing of eprosartan mesylate (EM) according to ICH guideline Q1A (R2), and development of a stability-indicating reversed phase ultra performance liquid chromatographic (UPLC) assay. The drug was subjected to acid (0.5N HCl), neutral and alkaline (0.5 N NaOH) hydrolytic conditions at 80 °C, and to oxidative decomposition at room temperature. Photolysis was carried out by exposing the drug during the day time to sunlight (60,000-70,000 lux) for two days and oxidative study was performed with 0.5 mg/ml in 30 % hydrogen peroxide (H2O2 ) at room temperature for 25 hr. The solid drug was also subjected to 50 °C for 30 days in a hot air oven. Degradation of the drug was found to occur under alkaline, acidic and neutral hydrolytic conditions. Separation of the drug and the degradation products was successfully achieved on a BEH (bridged ethylene hybrid) C18 column (1.7 µm, 2.1 mm × 150 mm) with gradient elution of water-acetonitrile as mobile phase. The flow rate and detection wavelength were 0.1 ml/min and 232 nm, respectively. The method was validated and the response was found to be linear in the drug concentration range 5-25 µg/ml (r2 = 0.999). The %RSD in intra-day and inter-day precision studies was < 0.8 %. Recovery of the drug from a mixture of degradation products was between 98.3 and 99.8 %. The LOD and LOQ of developed method were obtained at 0.15 µg/ml and 0.45 µg/ml respectively. The method was specific to the drug, selective to degradation products, and robust. PDA purity test also confirmed the specificity of the method.Colegio de Farmacéuticos de la Provincia de Buenos Aire

    RP-HPLC method for estimation and stability study of drotaverine HCl as per ICH guidelines

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    A validated stability indicating assay method was developed for the estimation of drotaverine HCl in the presence of its degradation products. The best separation of analyte was achieved in the C8 analytical column at ambient temperature using a mobile phase composition of methanol and ammonium acetate (75:25) in isocratic mode. The flow rate and the detection wavelength were set at 0.9 ml/min and 308 nm, respectively. The drug gives peak at RT 7.483 min and the forced degradation studies gave three degradation products peaks in which two degradation products (RT 4.202 and 5.010 min) were obtained from alkaline hydrolysis and the third product from neutral hydrolysis of the drug and was eluted at RT 5.842 min. The limit of detection (LOD) and limit of quantitation (LOQ) of the developed method was found to be 0.4 µg /ml and 1.4 µg/ml respectively. The validation results obtained from the analysis reveals that the developed method is simple, accurate, precise, specific and selective.Colegio de Farmacéuticos de la Provincia de Buenos Aire

    Effect of high-fat diet on the formation of pulmonary neutrophil extracellular traps during influenza pneumonia in BALB/c mice

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    Obesity is an independent risk factor for severe outcome of influenza infection. Higher dietary fat consumption has been linked to greater morbidity and severe influenza in mouse models. However, the extent of generation of neutrophil extracellular traps (NETs or NETosis) in obese individuals during influenza pneumonia is hitherto unknown. This study investigated pulmonary NETs generation in BALB/c mice fed with high-fat diet (HFD) and low-fat diet (LFD), during the course of influenza pneumonia. Clinical disease progression, histopathology, lung reactive oxygen species, and myeloperoxidase activity were also compared. Consumption of HFD over 18 weeks led to significantly higher body weight, body mass index, and adiposity in BALB/c mice compared with LFD. Lethal challenge of mice (on HFD and LFD) with influenza A/PR/8/34 (H1N1) virus led to similar body weight loss and histopathologic severity. However, NETs were formed at relatively higher levels in mice fed with HFD, despite the absence of significant difference in disease progression between HFD- and LFD-fed mice.Peer reviewedVeterinary Health Science

    Neutrophil Extracellular Traps Go Viral

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    Neutrophils are the most numerous immune cells. Their importance as the first line of defense against bacterial and fungal pathogens is well described. In contrast, the role of neutrophils in controlling viral infections is less clear. Bacterial and fungal pathogens can stimulate neutrophils extracellular traps (NETs) in a process called NETosis. Although NETosis has previously been described as a special form of programmed cell death, there are forms of NET production that do not end with the demise of neutrophils. As an end result of NETosis, genomic DNA complexed with microbicidal proteins is expelled from neutrophils. These structures can kill pathogens or at least prevent their local spread within host tissue. On the other hand, disproportionate NET formation can cause local or systemic damage. Only recently, it was recognized that viruses can also induce NETosis. In this review, we discuss the mechanisms by which NETs are produced in the context of viral infection and how this may contribute to both antiviral immunity and immunopathology. Finally, we shed light on viral immune evasion mechanisms targeting NETs

    Federated Benchmarking of Medical Artificial Intelligence With MedPerf

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    Medical artificial intelligence (AI) has tremendous potential to advance healthcare by supporting and contributing to the evidence-based practice of medicine, personalizing patient treatment, reducing costs, and improving both healthcare provider and patient experience. Unlocking this potential requires systematic, quantitative evaluation of the performance of medical AI models on large-scale, heterogeneous data capturing diverse patient populations. Here, to meet this need, we introduce MedPerf, an open platform for benchmarking AI models in the medical domain. MedPerf focuses on enabling federated evaluation of AI models, by securely distributing them to different facilities, such as healthcare organizations. This process of bringing the model to the data empowers each facility to assess and verify the performance of AI models in an efficient and human-supervised process, while prioritizing privacy. We describe the current challenges healthcare and AI communities face, the need for an open platform, the design philosophy of MedPerf, its current implementation status and real-world deployment, our roadmap and, importantly, the use of MedPerf with multiple international institutions within cloud-based technology and on-premises scenarios. Finally, we welcome new contributions by researchers and organizations to further strengthen MedPerf as an open benchmarking platform

    Design strategies for potentially superconducting organic polymers incorporating TTF and BEDT-TTF moieties

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    Includes bibliographical references (pages [52]-53).Previous experimental work in the design of organic superconductors have focused primarily on charge transfer salts such as D2X where Donor molecules have structure related to tetrathiafiilvalene (TTF) and BEDT-TTF , more commonly known as ET. No polymeric organic superconductors exist. In this work an approach to the design of such polymers is presented in which TTF and ET moieties are attached as pendant groups to known rigid-rod polymers, such as Poly [p-phenylene], or included as repeat units in alternating copolymer structures. Model compounds of these two categories have been synthesized, as well as representative copolymers which incorporate TTF units. This material will be tested over the next few years to determine if a superconducting phase can be generated by conventional electrochemical crystallization techniques in collaboration with Professor John Reynolds at The University of Florida.M.S. (Master of Science
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