Background The development of lupus low disease activity state (LLDAS) as a treat-to-target endpoint for SLE patients has been validated. Its attainment has been associated with improved outcomes. ...This study aims to show whether a machine learning model can yield good results in predicting whether a patient will achieve LLDAS on their succeeding assessment. Methods A total of 42,355 records of patients were retrieved from the APLC longitudinal study database. Three machine learning models – XGBoost, Random Forest, and Naive Bayes – were tested for their predictive power. Eighty percent of the data was used to train the models while thirty percent was used for validation. The data were normalized and all models were subjected to 10-fold cross-validation to prevent overfitting. Additionally, we compared the top ten most significant features of each model. Results Various metrics were used to measure the model’s predictive power. The results of our study showed that the Random Forest model scored the highest for specificity, PPV, and accuracy with 0.8450, 0.8182, and 0.8338, respectively. The XGBoost model topped the NPV metric with 0.8559 while the Naive Bayes model got the highest score for sensitivity with 0.8986. It is good to note that the score difference of Random Forest with the top sensitivity and NPV scores were only 0.0629 and 0.0085, respectively. For the significant features, only two features were present on all three models, namely the current LLDAS and proteinuria level. Three additional features were important for two models—whether the patient is taking prednisolone; time adjusted mean (TAM) SLEDAI score; and SLEDAI score. Conclusions The study showed and compared various machine learning models on their predictive power in determining whether a patient will achieve LLDAS on their next visit. The results determined that the current LLDAS, proteinuria levels, SLEDAI score (and TAM SLEDAI),
Anesthesiologists are dependent on specialized drugs and equipment being immediately available for patient care. Deficiencies in supplies impact on operating room efficiency and patient safety. In ...our institution, we do not have anesthesia assistants/aides and depend on general aides to stock anesthesia related equipment which resulted in many shortages. We hypothesized that a mobile app would be useful for tracking and reporting and informing changes to stocking resulting in an improvement in the supply of anesthesia equipment. Following institutional quality improvement approval, we developed an app to collect metrics (which included the last 2 months of paper documentation - September and October 2015) and the first 12 months of the app usage (November 2015 to November 2016). Descriptive statistics were used to analyze data from the app. The primary outcome was the number of reports made over time. Secondary outcomes include the impact of missing items on operating room efficiency and patient safety, the most commonly reported missing items, and the most common actions taken following the discovery of missing items. The app increased the reporting by more than 300% (compared to paper) over the first 2 months. Over the year, 549 items were reported missing. The most common category of missing items was airway related 274 (49.9%). The single most commonly reported missing item was the Wisconsin Laryngoscope Size 1 Blade 95 (17.3%). App users reported the missing item safety impact as high 86 (15.7%) times and efficiency impact as high 117 (21.3%) times. Changes to staffing and supply resulted in a decrease in missing items reported. Our results demonstrate that an app can be useful for reporting, tracking of real-time shortages of anesthesia equipment and is easy to design and implement. Furthermore, the app has generated useful and robust data that has led to staffing changes and improvements in the anesthesia equipment supply chain. The app design and use may be useful in other clinical areas.
Orientation control of thin film nanostructures derived from block copolymers (BCPs) are of great interest for various emerging technologies like separation membranes, nanopatterning, and energy ...storage. While many BCP compositions have been developed for these applications, perpendicular orientation of these BCP domains is still very challenging to achieve. Herein we report on a new, integration-friendly approach in which small amounts of a phase-preferential, surface active polymer (SAP) was used as an additive to a polycarbonate-containing BCP formulation to obtain perpendicularly oriented domains with 19 nm natural periodicity upon thermal annealing. In this work, the vertically oriented BCP domains were used to demonstrate next generation patterning applications for advanced semiconductor nodes. Furthermore, these domains were used to demonstrate pattern transfer into a hardmask layer via commonly used etch techniques and graphoepitaxy-based directed self-assembly using existing lithographic integration schemes. We believe that this novel formulation-based approach can easily be extended to other applications beyond nanopatterning.
Cylinder-forming Polystyrene-block-polycarbonate (PS-b-PC) high-χ block copolymers (BCP) were developed to extend the scaling beyond the most widely used BCP, poly(styrene-b-poly(methyl methacrylate) ...(PS-b-PMMA). In this work, two PC-containing BCPs, poly(styrene-b-trimethylene carbonate (PS-b-PTMC) and poly(styrene-b-methyl 5-methyl-2-oxo-1,3-dioxane-5-carboxylate) (PS-b-PMTC-Me) were synthesized using ring opening polymerization (ROP) of the cyclic carbonyl monomers from hydroxy-functional polystyrene (PS-OH) with diazabicyclo5.4.0undec-7-ene (DBU) as the base catalyst. Resulting BCPs were purified by fractionating in methanol:acetonitrile (MeOH:MeCN) solvent mixture to afford clean BCPs that are needed for thin-film applications. Thin-film morphologies and the orientation of the purified BCPs were determined using atomic force microscopy (AFM) analysis by coating the BCP solution on neutral underlayer modified substrates followed by short thermal annealing. It was observed that while the PS-b-PTMC domains oriented parallel to the surface, the PS-b-PMTC-Me BCP domains oriented perpendicular to the surface at similar thermal annealing temperatures without the use of topcoat or additives.
The intrinsic mechanical properties of a given material strongly depend upon its chemical nature: the organics tend to be soft, but tough, while the inorganic materials are hard but brittle and are ...prone to fracture. The later characteristic gets even worse for porous materials and is of major concern in the microelectronics industry as porous organosilicates (mainly inorganic) will constitute the insulating layers in future electronic devices. In this paper, we demonstrate that significantly tougher organosilicate glass thin-films prepared by sol–gel process, can be obtained by introducing carbon bridging units between silicon atoms present in the organosilicate network. A fracture energy value of 15 J/m
2
was measured, surprisingly higher than that for dense silicon dioxide (10 J/m
2
), suggesting mechanical properties that lie somewhere in between those of conventional glasses and organic polymers. We also found that the Young’s modulus follows a linear decay when porosity is introduced, a unique property when compared to traditional organosilicates. As a result, crack resistant films were obtained at high levels of porosity, opening potential applications in the fields of low-k materials for future integrated circuits, membranes, sensors, waveguides, fuel cells and micro-fluidic channels.
Cylinder-forming Polystyrene-block-polycarbonate (PS-b-PC) high-χ block copolymers (BCP) were developed to extend the scaling beyond the most widely used BCP, poly(styrene-b-poly(methyl methacrylate) ...(PS-b-PMMA). In this work, two PC-containing BCPs, poly(styrene-b-trimethylene carbonate (PS-b-PTMC) and poly(styrene-b-methyl 5-methyl-2-oxo-1,3-dioxane-5-carboxylate) (PS-b-PMTC-Me) were synthesized using ring opening polymerization (ROP) of the cyclic carbonyl monomers from hydroxy-functional polystyrene (PS-OH) with diazabicyclo5.4.0undec-7-ene (DBU) as the base catalyst. Resulting BCPs were purified by fractionating in methanol:acetonitrile (MeOH:MeCN) solvent mixture to afford clean BCPs that are needed for thin-film applications. Thin-film morphologies and the orientation of the purified BCPs were determined using atomic force microscopy (AFM) analysis by coating the BCP solution on neutral underlayer modified substrates followed by short thermal annealing. It was observed that while the PS-b-PTMC domains oriented parallel to the surface, the PS-b-PMTC-Me BCP domains oriented perpendicular to the surface at similar thermal annealing temperatures without the use of topcoat or additives.
To extend the scaling beyond the most widely used block copolymer (BCP), poly(styrene)-block-poly(methyl methacrylate) (PS-b-PMMA), a new organic high-χ BCP based was developed. ...Polystyrene-b-polytrimethylene carbonate (PS-b-PTMC) BCP was synthesized using ring opening polymerization (ROP) of trimethylene carbonate from hydroxy-functional polystyrene (PS-OH) with diazabicyclo5.4.0undec-7-ene (DBU) as the base catalyst. The resulting BCP was characterized by 1H nuclear magnetic resonance (NMR) and gel permeation chromatography (GPC) to confirm the complete chain extension of the polystyrene macroinitiator. For the DBU catalyzed BCP, the GPC trace revealed a trimodal distribution indicating the presence of coupling product and homo-PTMC impurity. Using purification techniques, homo-PTMC impurity was isolated to afford purified BCP. Thin-film morphologies of the non-purified and the purified BCPs on poly(methyl methacrylate) (PMMA) coated substrates followed by short thermal annealing were characterized using atomic force microscopy (AFM) analysis. The non-purified BCP showed island morphology with a step-height of 17 nm whereas the purified PS-b-PTMC showed a flat film with parallel cylinders of 16.4 nm pitch row-to-row distance. The ability for the PS-b-PTMC to self-assemble below 20-nm pitch resolution confirms the high interaction parameter, χ, between the PS and PTMC blocks and is a promising candidate as a high-χ BCP for directed self-assembly (DSA) application.
A method utilizing inductively coupled plasma mass spectrometry (ICPMS) as the element-selective detector with microwave-assisted nitric acid digestion as the sample pre-treatment technique was ...developed for the simultaneous determination of cadmium (Cd) and lead (Pb) in milk samples. The estimated detection limits were 0.09ìg kg-1 and 0.33ìg kg-1 for Cd and Pb, respectively. The method was linear in the concentration range 0.01 to 500ìg kg-1with correlation coefficients of 0.999 for both analytes.The method was validated using certified reference material BCR 150 and the determined values for Cd and Pb were 18.24 ± 0.18 ìg kg-1 and 807.57 ± 7.07ìg kg-1, respectively. Further validation using another certified reference material, NIST 1643e, resulted in determined concentrations of 6.48 ± 0.10 ìg L-1 for Cd and 21.96 ± 0.87 ìg L-1 for Pb. These determined values agree well with the certified values in the reference materials.The method was applied to processed and raw carabao milk samples collected in Nueva Ecija, Philippines.The Cd levels determined in the samples were in the range 0.11 ± 0.07 to 5.17 ± 0.13 ìg kg-1 for the processed milk samples, and 0.11 ± 0.07 to 0.45 ± 0.09 ìg kg-1 for the raw milk samples. The concentrations of Pb were in the range 0.49 ± 0.21 to 5.82 ± 0.17 ìg kg-1 for the processed milk samples, and 0.72 ± 0.18 to 6.79 ± 0.20 ìg kg-1 for the raw milk samples.
Metals like cadmium (Cd) and lead (Pb) are introduced in the environment through natural processes and anthropogenic activities and may end up being present in food, where these metals may pose ...health risks. A method suitable for the simultaneous determination of Cd and Pb in various matrices of foodstuffs was validated and applied to different samples including fruit juice, bottled iced tea, several types of condiments, and in edible tissues of dried fish locally produced in the Philippines. Fruit juice and bottled iced tea samples were filtered prior to quantification of metals using inductively coupled plasma mass spectrometry (ICP-MS). Condiments and dried fish samples were mineralized using microwave-assisted nitric acid digestion before subsequent metal detection with ICP-MS. The method was validated using certified reference materials DORM 3 and NIST 1643e, and evaluation of recovery of spiked samples. The method was linear in the concentration range 0.01 to 500 mu g L-1 with correlation coefficients of 0.999 for both analytes. The estimated detection limits were 0.060 mu gL-1 and 0.186 mu gL-1 for Cd and Pb, respectively. The determined levels of Cd in fruit juice were in the range 0.06 plus or minus 0.01 to 0.67 plus or minus 0.01 mu gL-1, and Pb was detected in only one sample at 0.37 plus or minus 0.02 mu gL-1. For the bottled iced tea samples, Cd was detected in only one sample (0.13 plus or minus 0.02 mu gL1) while none of the samples had detectable Pb concentration. For the condiments, the determined Cd levels were in the range 0.83 plus or minus 0.06 to 306.13 plus or minus 2.52 mu gL-1, whereas the determined Pb levels were in the range 2.14 plus or minus 0.38 to 67.45 plus or minus 7.76 mu gL-1. For the dried fish samples, the Cd levels determined were in the range 2.00 plus or minus 0.21 to 231.67 plus or minus 5.32 mu g kg-1 and that for Pb were in the range 2.38 plus or minus 0.70 to 113.29 plus or minus 2.25 mu g kg-1. These determined levels in different foodstuffs highlight the need for routine monitoring of these contaminants.
To extend the scaling beyond the most widely used block copolymer (BCP), poly(styrene)-block-poly(methyl methacrylate) (PS-b-PMMA), a new organic high-χ BCP based was developed. ...Polystyrene-b-polytrimethylene carbonate (PS-b-PTMC) BCP was synthesized using ring opening polymerization (ROP) of trimethylene carbonate from hydroxy-functional polystyrene (PS-OH) with diazabicyclo5.4.0undec-7-ene (DBU) as the base catalyst. The resulting BCP was characterized by 1H nuclear magnetic resonance (NMR) and gel permeation chromatography (GPC) to confirm the complete chain extension of the polystyrene macroinitiator. For the DBU catalyzed BCP, the GPC trace revealed a trimodal distribution indicating the presence of coupling product and homo-PTMC impurity. Using purification techniques, homo-PTMC impurity was isolated to afford purified BCP. Thin-film morphologies of the non-purified and the purified BCPs on poly(methyl methacrylate) (PMMA) coated substrates followed by short thermal annealing were characterized using atomic force microscopy (AFM) analysis. The non-purified BCP showed island morphology with a step-height of 17 nm whereas the purified PS-b-PTMC showed a flat film with parallel cylinders of 16.4 nm pitch row-to-row distance. The ability for the PS-b-PTMC to self-assemble below 20-nm pitch resolution confirms the high interaction parameter, χ, between the PS and PTMC blocks and is a promising candidate as a high-χ BCP for directed self-assembly (DSA) application.
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