New Log of the Columbia

"The second voyage [of the Columbia] is the one, during which the great discoveries were made. Any new light on those occurrences would be welcome, but historians in the Northwest were certainly not expecting a new journal giving a day-by-day record of the entire voyage. Just such a rich find has come to light in this John Boit journal.

The Effectiveness of Transfer Learning Systems on Medical Images

Deep neural networks have revolutionized the performances of many machine learning tasks such as medical image classification and segmentation. Current deep learning (DL) algorithms, specifically convolutional neural networks are increasingly becoming the methodological choice for most medical image analysis. However, training these deep neural networks requires high computational resources and very large amounts of labeled data which is often expensive and laborious. Meanwhile, recent studies have shown the transfer learning (TL) paradigm as an attractive choice in providing promising solutions to challenges of shortage in the availability of labeled medical images. Accordingly, TL enables us to leverage the knowledge learned from related data to solve a new problem. The objective of this dissertation is to examine the effectiveness of TL systems on medical images. First, a comprehensive systematic literature review was performed to provide an up-to-date status of TL systems on medical images. Specifically, we proposed a novel conceptual framework to organize the review. Second, a novel DL network was pretrained on natural images and utilized to evaluate the effectiveness of TL on a very large medical image dataset, specifically Chest X-rays images. Lastly, domain adaptation using an autoencoder was evaluated on the medical image dataset and the results confirmed the effectiveness of TL through fine-tuning strategies. We make several contributions to TL systems on medical image analysis: Firstly, we present a novel survey of TL on medical images and propose a new conceptual framework to organize the findings. Secondly, we propose a novel DL architecture to improve learned representations of medical images while mitigating the problem of vanishing gradients. Additionally, we identified the optimal cut-off layer (OCL) that provided the best model performance. We found that the higher layers in the proposed deep model give a better feature representation of our medical image task. Finally, we analyzed the effect of domain adaptation by fine-tuning an autoencoder on our medical images and provide theoretical contributions on the application of the transductive TL approach. The contributions herein reveal several research gaps to motivate future research and contribute to the body of literature in this active research area of TL systems on medical image analysis

Navigating the process of building parent-teacher partnerships: Experiences of early childhood pre-service teachers

This study utilized the qualitative phenomenological approach to explore pre -service teachers’ experiences in their engagement with parents of young children as they practiced building partnerships with parents. Pre-service teachers (N=50) were each assigned a preschool child with whom they interacted together with the child’s parents and teacher; completing a semester-long assignment created within a family, schools and community course for students in an early childhood teacher preparation program. Pre-service teachers’ responses to a survey and their final written reflections were analyzed using the process of axial and open coding. Results indicated the importance of communication and understanding different dynamics and challenges in parent-teacher partnerships. Therefore, educators should continuously strive to equip pre-service teachers with the skills they will need to succeed as they work with schools, the community and especially in their work with parents

The Efficacy of Administering Fruit-Derived Polyphenols to Improve Health Biomarkers, Exercise Performance and Related Physiological Responses

open access articlePolyphenols are secondary metabolites involved in a myriad of critical processes in plants. Over recent decades, special attention has been paid to the anti-oxidative role of fruit-derived polyphenols in the human diet, with evidence supporting the contribution of polyphenols in the prevention of numerous non-communicable disease outcomes. However, due to the low concentration in biological fluids in vivo, the antioxidant properties of polyphenols seem to be related to an enhanced endogenous antioxidant capacity induced via signaling through the nuclear respiratory factor 2 pathway. Polyphenols also seem to possess anti-inflammatory and antioxidant properties and have been shown to enhance vascular function via nitric oxide mediated mechanisms. Consequently, there is rationale to support fruit-derived polyphenol supplementation to enhance exercise performance, possibly via improved muscle perfusion. Fruit-derived polyphenol supplementation in exercise studies have included a variety of fruits, e.g., New Zealand blackcurrant, pomegranate, and cherry, in the form of extracts (multicomponent or purified), juices and infusions to varying degrees of benefit. For example, research has yet to link the health-related benefits of black elderberry (Sambucus nigra L.) ingestion to exercise performance in spite of the purported health benefits associated with black elderberry provision in vitro and in vivo models, which has been attributed to their high antioxidant capacity and polyphenol content. This review summarizes the existing evidence supporting a beneficial effect of fruit-derived polyphenols on various biological processes and outlines the potential for black elderberry ingestion to improve nitric oxide production, exercise performance, and the associated physiological responses before-, during- and post-exercise

Imobilização de lipases em filmes de poli(álcool vinílico) e carbOximetilcelulose

TCC (graduação) - Universidade Federal de Santa Catarina. Centro de Ciências Físicas e Matemáticas. Curso de Química.As enzimas em sua maioria são catalisadores de natureza protéica. São versáteis, existindo um processo enzimático equivalente para vários tipos de reações orgânicas. Técnicas de imobilização vem sendo desenvolvidas para fornecer estabilidade para enzimas em meio orgânico, facilitando sua recuperação e reutilização. O ponto de partida desse trabalho foi a imobilização das lipases de Rhyzopous oryzae (LRO, 50mg - 150000u/g) ou de Mucor javanicus (LMJ, 50mg - 10000u/g) em filmes de carbóximetilcelulose(CMC,500mg em 25mL de água), poli(álcool vinílico) (PVA, 500mg em 25mL de água) e de PVA/CMC (250 mg de cada polímero em 25mL de água) e a utilização desses sistemas na catálise de reações de esterificação em quantidades equimolares de ácido e álcool, utilizando n-hexano como solvente externo. Primeiramente foram feitas reações utilizando as LRO e LMJ livres como biocatalisadores na esterificação dos ácidos láurico e esteárico com n-pentanol. Foram efetuados também estudos de esterificação dos ácidos decanóico, láurico, mirístico, palmítico e esteárico com n-pentanol utilizando a LRO e a LMJ imobilizadas em filmes de CMC, PVA e CMC:PVA(1:1). A maioria dos ésteres formaram-se em rendimentos quantitativos, exceto para os ácidos decanóico e mirístico que apresentaram 51% e 68% respectivamente de conversão em éster quando foi utilizado o sistema LRO/CMC:PVA. Na sequência foram feitas reações de esterificação dos ácidos insaturados 4-pentenóico, sórbico, 2-octenóico, linoleico e oleico com o n-pentanol. Os resultados obtidos mostraram que de forma geral os ésteres derivados do ácido oleico foram obtidos em maiores conversões (>90%). Também, pode-se destacar o resultado obtido na esterificação do ácido linoleico com o sistema LRO/CMC (72%). Na continuidade do trabalho, efetuaram-se estudos de esterificação do ácido láurico com etanol, propanol, butanol, pentanol, hexanol, octanol, decanol e octadecanol, utilizando as enzimas LRO e LMJ, imobilizadas em filmes de CMC, PVA e CMC:PVA. As melhores conversões em ésteres foram obtidas para álcoois de 2 a 5 átomos de carbono (>99%) em todos os sistemas. Para os álcoois de cadeia maiores as conversões foram de aproximadamente 80% com a LMJ imobilizada. Fêz-se também um estudo de esterificação do ácido láurico com os álcoois ramificados como o isopropanol, terc-butanol e isobutanol utilizando os sistemas descritos anteriormente. Nestas reações de esterificação não foram detectadas a formação de produtos, evidenciando a importância de efeitos estéreos

Extrinsic Factors Influencing the Effective Use of Security Awareness Guidelines: A Comparative Study between a Bank and a Telecommunications Company

Recently, the telecommunication and banking industries, regarded as key infrastructures of a country’s economy, are experiencing a rapid transformation driven by changing consumer behaviors, increased competitive environment and new innovations, for example mobile technology. Thus, the purpose of this study is to investigate the influence of extrinsic factors on the behavioral decisions of users to effectively use a security awareness program. This study is quantitative in nature and explores the relationship between effective information use and other variables namely; management support, reward, punishment, social pressure, information quality and attitude. The results of the empirical testing demonstrate that information quality and attitude of employees are relevant factors towards using a security awareness program. Our results also show that reward and threat of punishment are less relevant factors

The efficacy of retirement plans and flexible scheduling in improving the quality of service delivery among civil servants in Nandi south Kenya

ABSTRACT Retirement plans and flexible scheduling guides most organizations and is part of most complaints of citizen’s due to poor service in government counties such complaints was reflected during the year 2002 Constitutional Referendum in Kenya which in part called for an overhaul of the civil service structure through various Civil Service Reform Programmes and major reshuffles. This paper highlighted therefore the effects of these variables in service delivery within Civil Service offices in Kenya: A case of Nandi south. Stratified random sampling techniques were used to select 350 employees of Nandi south. Data collected through the use of questionnaires was analyzed using both descriptive and regression statistics. Descriptive findings revealed that there was low level of retirement plan services to the employees of Nandi south. Nevertheless, high levels of Flexible Scheduling services among employees were observed an indicator that retirement plans in the Workplace had significant effect on Service Delivery. Keywords: Services Delivery, Workplace, Retirement Plans and Flexible Schedulin

Malaria Surveillance System Using Social Media

Social media, for example, Twitter has increasingly provided opportunities for massive data collection of topical issues affecting today’s society. Opinions and data in public health issues are very prevalent on Twitter and provide an invaluable source of interesting information that can be mined for decision making in public health organizations. This paper discusses the existing malaria surveillance system and proposes a malaria surveillance system (MSS) that leverages social media with a view to enhancing decision making by public health professionals. The MSS system comprises of a data collection module, analysis engine, and a metrics module. The practical contribution of this research is the construction of a conceptual architecture for the MSS

EFFECTIVENESS OF TRANSFER LEARNING ON MEDICAL IMAGE CLASSIFICATION USING CHEST-XRAY 14 DATASET

https://scholar.dsu.edu/research-symposium/1024/thumbnail.jp