82 research outputs found
Commercial Regional Space/Airborne Imaging
In this work goal programming is used to solve a minimum cost multicommodity network flow problem with multiple goals. A single telecommunication network with multiple commodities (e.g., voice, video, data, etc.) flowing over it is analyzed. This network consists of: linear objective function, linear cost arcs, fixed capacities, specific origin-destination pairs for each commodity. A multicommodity network flow problem with goals can be successfully modeled using linear goal programming techniques. When properly modeled, network flow techniques may be employed to exploit the pure network structure of a multicommodity network flow problem with goals. Lagrangian relaxation captures the essence of the pure network flow problem as a master problem and sub-problems (McGinnis and Rao, 1977). A subgradient algorithm may optimize the Lagrangian function, or the Lagrangian relaxation could be decomposed into subproblems per commodity; each subproblem being a single commodity network flow problem. Parallel to the decomposition of the Lagrangian relaxation, Dantzig-Wolfe decomposition may be implemented to the linear program. Post-optimality analyses provide a variety of options to analyze the robustness of the optimal solution. The options of post-optimality analysis consist of sensitivity analysis and parametric analysis. This mix of modeling options and analyses provide a powerful method to produce insight into the modeling of a multicommodity network flow problem with multiple objectives
Discutindo a educação ambiental no cotidiano escolar: desenvolvimento de projetos na escola formação inicial e continuada de professores
A presente pesquisa buscou discutir como a Educação Ambiental (EA) vem sendo trabalhada, no Ensino Fundamental e como os docentes desta escola compreendem e vem inserindo a EA no cotidiano escolar., em uma escola estadual do município de Tangará da Serra/MT, Brasil. Para tanto, realizou-se entrevistas com os professores que fazem parte de um projeto interdisciplinar de EA na escola pesquisada. Verificou-se que o projeto da escola não vem conseguindo alcançar os objetivos propostos por: desconhecimento do mesmo, pelos professores; formação deficiente dos professores, não entendimento da EA como processo de ensino-aprendizagem, falta de recursos didáticos, planejamento inadequado das atividades. A partir dessa constatação, procurou-se debater a impossibilidade de tratar do tema fora do trabalho interdisciplinar, bem como, e principalmente, a importância de um estudo mais aprofundado de EA, vinculando teoria e prática, tanto na formação docente, como em projetos escolares, a fim de fugir do tradicional vínculo “EA e ecologia, lixo e horta”.Facultad de Humanidades y Ciencias de la Educació
Computational Studies on Novel Atomic Force Microscopy Techniques and Plasmonic-Enhanced Organic Photovoltaics
Thesis (Ph.D.)--University of Washington, 2015-12In physical and life sciences, employing computational approaches to understand the nature of studied materials and subjects and to analyze immense amount of data is increasingly becoming more popular. Using existing methods and techniques is surprisingly easy, however these are not always well-suited for the problem at hand. Developing new methods specific to a problem requires a deep understanding of the problem, the underlying physics and relevant computational methods. Atomic Force Microscopy (AFM) is a unique tool for studying different properties of materials, such as conductivity, surface topography and forces. It also is a flexible tool for developing novel techniques that enable new studies in many fields of science. Although AFM is versatile, it can still be challenging to implement novel methods. Here, we describe in detail the hardware and the software implementation of simultaneous data acquisition and analysis in fast time-resolved electrostatic force microscopy (trEFM). Fast trEFM can measure nanosecond-scale local dynamics using widely available AFM hardware. We computationally and experimentally investigate the limits of trEFM and show that we can discriminate signal rise times with time constants as fast as 10 ns. Dynamic Force Spectroscopy is another method that is based on AFM and widely used in life sciences to measure mechanical properties of tissues, cells and DNA. We investigate computational methods to analyze force curves resulting from DNA pulling experiments in order to understand the unbinding kinetics of DNA under mechanical loading. We demonstrate that we can automate analysis of force curves using modern machine learning algorithms with an accuracy rate of 94%, which is approximately equal to human experimenters’ scores. Another area to which one can apply computational methods is modeling organic photovoltaic devices. Organic photovoltaics (OPVs) are one potential solution to growing demand for clean and inexpensive energy. Fabricating organic solar cells is a relatively easy process; the challenge is to make them as efficient as their inorganic counterparts. To increase the performance of an OPV device, one can use many different approaches, such as changing the device architecture or incorporating metal nanoparticles. Here, we study performance limits of plasmon-enhanced organic photovoltaics using a combination of computational modeling and experiment. We model modern low-bandgap donor polymer-fullerene blends with variety of colloidal silver nanoparticles to understand how sensitive the device performance is to nanoparticles. We show that it is possible to achieve an enhancement of 31% in short-circuit current density
Neden erteliyoruz? Bir grup üniversite öğrencisiyle psikodrama çalışması
The aim of this study is to examine the effect of psychodrama group study on students' procrastination behaviour. The research was done as a single group quasi-experimental, pre-test post-test study design. The research sample consisted of 14 nursing students who volunteered and fulfilled the criteria of the study. A Personal Information Form and Tuckman Procrastination Scale used in collecting the data. The Tuckman Procrastination Scale scores of the students were decreased significantly (p<.05). In the early stages of the group process the themes that came forward in the protagonist plays such as friendship issues, anxieties related to academic success and procrastinating study extended also to involve the relationships with the family members such as mother, father and siblings in the following sessions. The gifts exchanged during the group play in the last session, showed the high awareness level of group members of one another's needs. According to the results, it can be said that psychodrama group study has a positive effect on procrastination behaviour of students. Research result is limited with this study and it is important that similar studies about procrastination increase in number
Weakness in the Emergency Department: Hypokalemic Periodic Paralysis Induced By Strenuous Physical Activity
SUMMARY: Hypokalemic periodic paralysis is a rare but serious disorder that is typically caused by a channelopathy. Thyrotoxicosis, heavy exercise, high carbohydrate meal and some drugs can trigger channelopathy in genetically predisposed individuals. A 33-year-old male patient presented to the emergency department with weakness in the lower extremities. He stated that he had done heavy physical activity during the previous week. The patient exhibited motor weakness in the lower extremities (2/5 strength) during the physical examination. Initial laboratory tests showed a potassium level of 1.89 mEq/L. The initial electrocardiogram demonstrated T wave inversion and prominent U waves. The patient was treated in the emergency department with oral and intravenous potassium. The physical and ECG symptoms resolved within 16 hours of potassium supplementation and biochemical tests showed normal serum potassium levels. The patient was discharged shortly after the resolution of the symptoms. Weakness is an important but nonspecific symptom that may be brought on by a number of underlying physiological processes. Hypokalemic periodic paralysis is a rare disease that may be triggered by heavy physical activity and presents with recurrent admissions due to weakness. Key words: Emergency department, hypokalemic periodic paralysis, muscle weaknes
Tbx3 represses PTEN and is over-expressed in head and neck squamous cell carcinoma
Abstract Background Despite advances in diagnostic and treatment strategies, head and neck squamous cell cancer (HNSCC) constitutes one of the worst cancer types in terms of prognosis. PTEN is one of the tumour suppressors whose expression and/or activity have been found to be reduced in HNSCC, with rather low rates of mutations within the PTEN gene (6-8%). We reasoned that low expression levels of PTEN might be due to a transcriptional repression governed by an oncogene. Tbx2 and Tbx3, both of which are transcriptional repressors, have been found to be amplified or over-expressed in various cancer types. Thus, we hypothesize that Tbx3 may be over expressed in HNSCC and may repress PTEN, thus leading to cancer formation and/or progression. Methods Using immunohistochemistry and quantitative PCR (qPCR), protein and mRNA levels of PTEN and Tbx3 were identified in samples excised from cancerous and adjacent normal tissues from 33 patients who were diagnosed with HNSCC. In addition, HeLa and HEK cell lines were transfected with a Tbx3 expressing plasmid and endogenous PTEN mRNA and protein levels were determined via qPCR and flow cytometry. Transcription assays were performed to demonstrate effects of Tbx3 on PTEN promoter activity. Mann–Whitney, Spearman’s Correlation and Wilcoxon signed-rank tests were used to analyze the data. Results We demonstrate that in HNSCC samples, Tbx3 mRNA levels are increased with respect to their normal tissue counterparts (p Conclusions We show that Tbx3 is up-regulated in tissue samples of HNSCC patients and that Tbx3 represses PTEN transcription. Thus, our data not only reveals a new mechanism that may be important in cancer formation, but also suggests that Tbx3 can be used as a potential biomarker in cancer.</p
A rare complication of spinal anesthesia: Intracranial subdural hemorrhage
Spinal (subarachnoid) anesthesia (SA) is a widely used general-purpose anesthesia. Postdural Puncture Headaches (PDPHs) represent one of the principal complications of spinal anesthesia. A 21-year-old man underwent inguinal herniorrhaphy and orchiectomy using spinal anesthesia. Postoperatively, our patient started to have a headache with nausea. The patient received symptomatic therapy, but the severe headache persisted even in the supine position, with his vital signs and neurological examination being normal. Cranial MRI showed a bilateral subdural hematoma from his frontal to temporal region. A postdural puncture headache is a frequent complication after spinal anesthesia. However, serious complications, such as an intracranial subdural hemorrhage, can rarely occur. [Arch Clin Exp Surg 2015; 4(1.000): 54-56
Is there a relation between the changes in circulating lymphocyte counts due to neoadjuvant chemoradiotherapy and intratumoral lymphocytic response and tumor regression grade in locally advanced rectal cancers?
There are controversies about the relation between the peripheral lymphocyte levels and response to neoadjuvant therapy. While some authors have reported that a positive correlation between peripheral lymphocyte levels and tumor response, others have suggested the opposite. In the present study, we aimed to investigate the possible relations between the changes in circulating lymphocyte counts due to neoadjuvant chemoradiotherapy (CRT) and intratumoral lymphocytic response (ILR) and tumor regression grade (TRG) in locally advanced rectal cancers. Lymphocyte levels before, during and after CRT as well as before surgery and pathologic findings including ILRs and TRGs were recorded. Lymphocyte levels before CRT were accepted as absolute values. After the changes in the lymphocyte levels during and after CRT and before the surgery were recorded as ratios to the absolute values, the relation between the changes in lymphocyte levels, ILR and TRG were studied by using Pearson and Spearman correlation tests. There was a positive correlation between changes in peripheral lymphocytic levels after neoadjuvant CRT and ILRs. However, there were no other correlations between changes in lymphocytic levels and TRGs and ILRs. The changes in the peripheral lymphocyte counts after CRT may be predictive for ILR. Further studies may provide more information about the relation between peripheral lymphocytes and TILs and tumor response to neoadjuvant CRT. [Med-Science 2017; 6(4.000): 640-642
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