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Using Machine Learning to Predict Bacteremia in Emergency Room Patients
No full textBacteremia refers to the presence of bacteria in the bloodstream. It can be acquired through various means, from simple activities like brushing teeth to infections during surgical procedures. Untreated bacteremia can lead to multiple complications, with sepsis having a mortality rate as high as 40%.
Treating bacteremia involves administering appropriate antibiotics based on the specific type of bacteria present. Diagnosis of bacteremia relies on the results of blood cultures, which typically take around 72 hours. Patients suspected of bacteremia in the emergency room often require immediate antibiotic therapy, as each hour of delay significantly increases the mortality rate. Before blood culture results are available, clinicians usually select antibiotics based on their clinical experience. However, studies have shown that blood culture results frequently reveal inadequate or incorrect initial antibiotic choices.
This research aims to predict emergency room patients' blood culture results (positive or negative) using machine learning methods. Data collected from 2013 to 2021, comprising 84,798 records, include information in the emergency room, such as demographics, clinical information, past medical history, and blood test reports (usually available within an hour). The data is heavily imbalanced between negative and positive blood culture results, so undersampling, oversampling (SMOTE), and weighting techniques are employed to balance the data.
Variables in the dataset are ranked based on the chi-square test and Student's t-test, and machine learning models such as Logistic Regression, Support Vector Machine (SVM), Random Forest, XGBoost, and LightGBM are used for prediction. The main evaluation metrics are recall and accuracy.
Furthermore, the study presents the feature importance of Logistic Regression, Random Forest, XGBoost, and LightGBM models to identify the top-ranking variables in univariate and multivariate analyses. The study aims to understand the explanatory power of these variables in the model and compare their importance with findings from other research or practical clinical diagnoses
Investigating the Key Indicators of Transboundary Marine Spatial Planning based on Multi-Criterion Decision Making- Case of Kinmen-Xiamen Sea Area
No full textIn recent years, new marine activities like renewable energy and tourism have affected traditional maritime uses for fishing and shipping. The Ocean Affairs Council is actively working on the development of legal frameworks for marine spatial planning and management of marine resources to ensure effective coordination of various maritime uses and mitigate potential conflicts between the development of marine economy and environment. Transboundary Marine Spatial Planning (TMSP) has emerged as a crucial international tool for marine governance. TMSP has been internationally recognized as an effective approach to resolve conflicts over shared ocean uses.
There are some geographic advantages and rich marine resources in the Kinmen-Xiamen Sea area. However, due to urban development between the two sides, issues such as marine waste and seabed mining are derived. Due to the emerging conflicts, applying the Delphi method and DEMATEL-based Analytical Network Process (DANP) to conduct an in-depth analysis is the solution.
Firstly, this study established 3 dimensions and 12 key indicators for TMSP. The ecological sustainability dimension is comprised of 5 indicators: "reducing marine waste pollution," "preventing coastal erosion and habitat destruction," "ecological diversity assessment and monitoring," "transboundary marine environmental resource sharing and maintenance," and "increasing the proportion of marine protected areas." The industrial prosperity dimension includes 4 indicators: "sustainable fishery resources," "tourism development," " transboundary economic cooperation," and " transboundary socio-economic infrastructure guarantee." The maritime safety dimension is comprised of 3 indicators: "enhancing law enforcement capacity, strengthening and maintaining maritime security, " "maritime safety maintenance," and " transboundary cooperative marine governance mechanism."
The study used the DANP expert questionnaire to calculate weight values and rankings for each indicator based on government agencies, academia, and civil society's perceptions. The findings show that all three groups prioritize the "transboundary cooperative marine governance mechanism" indicator, followed by "enhancing law enforcement capabilities and strengthening maritime security." Prioritizing these indicators will impact others and promote regional ocean governance, facilitating sustainable development in the Kinmen-Xiamen Sea area
Assessment of factors influencing Physicians' premedication for blood transfusion
No full textAbstract
It is unnecessary to mention low-value care about blood transfusion in Choosing Wisely American Association of Blood Banks. However, blood transfusion, as the most common treatment in medical procedures, is clinically effective in improving the ischemic condition of patients, so many Blood transfusion is inevitable, and blood transfusion may sometimes cause adverse reactions in the body, that is, transfusion reactions. Therefore, many physicians may consider prescribing antihistamine drugs at the same time before a blood transfusion to reduce the occurrence of blood transfusion reactions. However, According to past medical data and literature, it is shown that giving antipyretics or antiallergic drugs to patients before blood transfusion does not significantly reduce the occurrence of febrile non-hemolytic transfusion reactions or allergic reactions. Excessive low-efficiency medical behaviors will not only increase medical costs but also reduce quality of care. Therefore, through this study, qualitative interviews combined with "Theory of Planned Behavior" are used as the theoretical construction and added five personality traits questionnaires to explore the factors and obstacles that doctors mainly prescribe pre-transfusion medication.
In this study, practicing physicians in medical institutions across Taiwan were used as the research object. The google form online questionnaire was used to conduct the survey. A total of 283 questionnaires were collected and three physicians from southern public medical centers were interviewed. This study used SPSS version 20 and STATA version 14.0 for data processing and analysis, the analysis includes descriptive statistics, independent sample T test, single factor analysis of variance, Pearson correlation analysis and regression analysis for data processing, the major results are as follows (1) Perceived behavior control significantly positively correlated with physician prescribed premedication behavioral intentions and subjective norms of pre-blood transfusion prophylaxis were significantly negatively correlated with the behavioral intentions of physicians to execute pre-blood transfusion prophylaxis; (2) The frequency of pre-blood transfusion prophylaxis orders by physicians had significant differences in attitude, subjective norms, and behavioral intentions (3) The five major personality traits can be used to predict the attitude, subjective norms, perceived behavioral control, and behavioral intentions of doctors prescribing pre-transfusion prophylaxis; (4) According to interviews, doctors mainly refer to patients' allergies when prescribing medical orders. history as the basis, and the request of nurses, the teaching of predecessors and their own experience will affect the decision-making factors. The obstacles encountered in the process of reducing prescriptions are the pressure from nurses, past experience, and preventive psychology. In the clinical environment, although physicians believe in the existence of evidence-based medicine, they still take their own experience as the main consideratio
Using Onboard-Produced Drinking Water to Achieve Ballast Water-Free Management
No full textBased on the International Convention for the Control and Management of Ships\ue2 Ballast Water and Sediments (the Ballast Water Management Convention, or BWM Convention) of the International Maritime Organization, from September 8, 2017, all ships must be equipped with an approved type of Ballast Water Management Treatment System (BWTS) to prevent the invasion of marine alien species through the discharge of ballast water. Generally speaking, the need for an approved BWTS is limited to large vessels, as they are too large or too expensive for small vessels (<500 Gross Tonnage) to install. This study aims to propose a simple ballast water-free approach for small vessels (e.g., tugs, workboats, research vessels) that require ballast water to compensate for the weight loss of fuel combustion during sailing. Our approach involves refitting the dedicated ballast tank of these small vessels to be drinking water tanks and filling the tanks with onboard-generated distilled or reverse osmosis water to adjust the stability of the ships. We assessed our approach using three vessels. Two ships using our proposed method were certified by the American Bureau of Shipping as containing no ballast water tank, and not being subject to the BWM Convention. On the other hand, since seawater corrodes the ballast water tank more than drinking water, and the life of the ship is depended by the life of the ballast water tanks. Therefore, using this method can effectively reduce the corrosion rate and improve the service life of the ship. This study provides an environmentally harmless, easy to use, and economical approach for small vessels to comply with the BWM Convention
Ammonium trichloro(dioxoethylene-o,o')tellurate inhibits tumor migration by down-regulation of heparanase through AKT/mTOR signaling pathway
No full textTellurium is a rare element in the human body. And ammonium trichloro(dioxoethylene-o,o')tellurate ( AS101 ) is the most bioactive among several synthetic tellurium compounds. AS101 was found to be immunomodulatory, which can modulate cytokines. However, the effect of AS101 on tumor metastasis remains unclear. Heparanase, which is an endo-\uce\ub2-D-glucuronidase, cleaves heparin sulfate side chains of proteoglycans on the cell surface, further leading to the degradation of the extracellular matrix. It also releases angiogenic factors in the extracellular matrix. It over-expresses tumor cell and promotes tumor metastasis and angiogenesis. Our study investigated the effect of AS101 in 4T1 and CT26 cells, especially on heparanase. Herein, the expression of heparanase was decreased in 4T1 and CT26 cells after treatment of AS101 in vitro. And those protein level involved in AKT/mTOR signaling pathway was also declined. Cell migration assay revealed the inhibitive ability of migration of AS101. This study indicates AS101 inhibits tumor migration by down-regulation of heparanase through AKT/mTOR signaling pathway and ends up bringing positive effect in vivo
Design of Middle to Long Range Automotive Radar Antenna in Package with Tapering Structure and Parasitic Elements
No full textIn recent years, advanced driver assistance systems (ADAS) have been developed vigorously. Adaptive Cruise Control (ACC) systems have become a common vehicle electronic assistance system. The traditional vehicle radar operated at 24 GHz. However, with the increase in the amount of processing information and high-resolution., the 76-81 GHz frequency band is mainly used for automotive radar antenna nowadays. With the advantages of broad bandwidth and lower interference, it can meet the demand of automotive radar and become the main design.
The antenna design of the ACC system is mainly based on the PCB, and the antenna and the RF chip need to keep a certain distance to avoid radiation interference between each other. However, such a circuit layout will increase the module area, and the cost is difficult to reduce. Using AIP technology, the area can be greatly reduced and the module can be minimized to achieve low-cost. This thesis proposed a series-fed packaged patch antenna which operates at 77 GHz. Inset feeding and tapering patch are used to control the current distribution on patches and make the main beam more concentrated to get a better radiation pattern. Adding parasitic patches can increase coupling and achieve higher antenna gain. Then, the electromagnetic energy gap (EBG) is used to improve the isolation and reduce the mutual interference between antennas. In final step, the antenna extended to 4x6 antenna array whose bandwidth is about 7%, covering the entire 76 GHz to 81 GHz automotive radar frequency band
The Representation of Environmental Sustainability: John Muir\ue2s Wilderness Preservation and His Creation of National Park
No full textJohn Muir (1838-1914), a Scottish-American writer, is known as \ue2father of National Parks.\ue2 Muir is one of early nature writers who advocated the preservation of
wilderness in America. Most of his works intended to represent his experiences and adventures in America\ue2s wild nature, and these representations are related to
wilderness preservation. To preserve the wild nature in America, Muir dedicated himself to establishing Yosemite National Park and other national parks in America. He envisioned Yosemite\ue2s gorgeous volcanic environment as the pristine land. In addition, he maintained and advocated that national parks possess the function for healing, inspiration and meditation. Likewise, Muir encouraged the residents in cities
to learn from wild nature\ue2s instructive power of life and wild nature\ue2s spiritual nourishment.
This thesis concentrates on offering an overview of the different attitudes toward America\ue2s wilderness between Muir\ue2s attitude and the attitude of most early European settlers from the seventeenth century to the nineteenth century. Most early pioneers and settlers who came from Europe held utilitarian attitude toward the wild nature: they believed that the natural resources in American wilderness were available and
inexhaustible. In contrast, Muir maintained that the rarity and biodiversity of the wilderness in America need to be perfectly protected. Also, this thesis will compare and discuss Muir\ue2s and Gifford Pinchot\ue2s (1865-1946) different perspectives about protecting the wilderness environment. Finally, this thesis focuses on Muir\ue2s Our National Park to explore the significance of seeking the connection between the creation of National Park and the idea of environmental sustainability. In actuality, the target of Muir\ue2s Our National Parks mainly highlights on the area of sustainable development
Simulating the Penetration of Bulk Palladium by Hydrogen
No full textThis study employs density functional theory (DFT) calculations and the kinetic Monte Carlo (kMC) method to investigate the kinetic behavior of H atoms on/in Pd. First, DFT calculations have been used to identify the stable adsorption sites of H atoms on/in Pd(100) and Pd(111). Then, the H diffusion pathways and their barriers have been identified. These DFT energetics have been used to calculate rate constants and used for kMC modeling. The kMC model has been built up stepwise. First, the analysis has started with a model that only considered hydrogen adsorption and desorption. Then the horizontal diffusion within one metal layer and vertical diffusion between adjacent layers of H have been included successively. It has been found that the horizontal diffusion substantially impacts the modeled hydrogen uptake. In contrast, the vertical diffusions are much slower and hardly seen in the kMC simulation. To approximate the vertical diffusion, it is necessary to use a modified kMC model in which the horizontal diffusion steps are limited. In addition, it has been found that, at room temperature, tunneling effects only play a negligible role for the H diffusion kinetics
Exploring the influence of metal oxide particle shape on antibacterial activity
No full textThis study demonstrated simple hydrothermal methods for synthesizing three different morphologies of copper oxide nanoparticles: (i) CuO rod, (ii) CuO flower, and (iii) CuO echinus to study the effect of morphologies and physical properties on antibacterial activity toward Escherichia coli. The crystal structure, morphology, crystallinity, surface area, zeta potential, Cu2+ ion, bandgap energy, and photoluminescent properties were characterized. In comparison to other morphologies (flower, echinus), the CuO rod shown showed the greatest antibacterial activity against Escherichia coli at the MICs and MBCs concentrations due to their morphologies and oxygen vacancy defects. They can produce reactive oxygen species (ROS) under dark conditions and possibly induce cytotoxicity. Furthermore, the antioxidant and antibacterial activity of these particle structures were investigated. DPPH and H2O2 free radical scavenging activities were used to evaluate the antioxidant activity of these particle structures. The antioxidant activity of DPPH and H2O2 showed that CuO rod was found to be 73.46 and 92.75% in 5 minutes. The results showed that the CuO rod could be identified as the most effective antibacterial after 6 hours at the lowest concentration of 700 \uc2\ub5g/ml, reaching 100%. Overall, the CuO rod is the most efficient antioxidant and antibacterial agent for pathogens. These particles have been proposed for use in the development of antibacterial materials and also for other cell treatment applications
A Study of Reconstructing MR Spectroscopic Imaging Using Deep Complex CNN
No full textMagnetic Resonance Spectroscopic Imaging (MRSI) provides a non-invasive imaging approach to detect the concentration and distribution of metabolites in human tissues. It has been widely applied in medical research for diagnostic evaluation and treatment. However, MRSI requires a considerable amount of scanning time due to its larger coverage and higher spatial resolution demands, which limits its clinical use. To shorten the scanning time and improve image quality, different fast MR imaging techniques such as Parallel Imaging (PI) and Compressed Sensing (CS) have been proposed and applied in MRSI. In recent years, Deep Learning (DL) has made significant advancements in image processing and has been widely used in the reconstruction of medical images. With the improvement in computational power, deep learning offers new possibilities for accelerating the development of MRSI.
Unlike conventional deep learning networks that process data in real numbers, complex neural networks can effectively handle complex data and phase information. In this study, a complex convolutional neural network namely Deep ResNet was employed for MRSI reconstruction. We apply undersampled (R=2) k-space data as training and testing dataset for deep learning retrospectively. Our results validate the feasibility of using a complex convolutional neural network for MRSI reconstruction. It can effectively recover the peaks of metabolites in the spectrum and also accurately restore the concentrations of metabolites in a large region of the brain. In small region of interest, it can exhibit relatively low concentration errors. In summary, the study has successfully utilized a Deep ResNet model to reconstruct the raw MRSI data in k-space, offering promising potential applications in the field of MRSI