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Neglected spatiotemporal variations of model biases in ensemble‐based climate projections
No full textThe Bayesian model averaging (BMA) method has been widely used for generating probabilistic climate projections. However, the averaging weights used in BMA can only reflect the spatially- and temporally-averaged performance of each ensemble member, without the ability to address the spatiotemporal variations of model biases. This can lead to inevitable exaggeration or understatement of the contributions of individual members to the ensemble mean, thus reducing the robustness of the resulting probabilistic projections. Here we propose a new method to help address the neglected spatiotemporal variations of model biases. Through the proposed method, the BMA weights are used as prior distributions to drive the Bayesian discriminant analysis in order to generate refined weights for individual ensemble models according to their spatially- and temporally-clustered performance. Through applying the proposed method to Canada, we demonstrate its effectiveness in generating robust probabilistic climate projections (e.g., the average R2 increases from 0.82 to 0.89).Canada Research Chair ProgramNatural Science and Engineering Research Council of CanadaWestern Economic Diversifica-tionNatural Science FoundationMITAC
Analysis of a closed-loop digital twin using discrete event simulation
No full textGiven recent advancements in technology and recognizing the evolution of smart manufacturing, the implementation of digital twins for factories and processes is becoming more common and more useful. Additionally, expansion in connectivity, growth in data storage, and the implementation of the industrial internet of things (IIoT) allow for greater opportunities not only with digital twins but with closed loop analytics. Discrete event simulation (DES) has been used to create digital twins and, in some instances, fitted with live connections to closely monitor factory operations. However, the benefits of a connected digital twin are not easily quantified. Therefore, a test bed demonstration factory was used, which implements smart technologies, to evaluate the effectiveness of a closed-loop digital twin in identifying and reacting to trends in production. This involves a digital twin of a factory process using DES. Although traditional DES is typically modeled using historical data, a DES system was developed which made use of live data to improve predictions. This model had live data updated directly to the DES model without user interaction, creating an adaptive and dynamic model. It was found that this DES with live data typically provided more accurate predictions of future performance and unforeseen near future problems when compared to the predictions of a traditional DES using only historic data, resulting in smarter decisions and implementation of more timely solutions
A comparison of egg white and egg yolk in gluten-free bread
No full textGluten-free breads made with egg whites, two-thirds egg white to one-third egg yolk, two-thirds egg yolk to onethird egg white, or egg yolks, were evaluated through sensory and mechanical testing. Breads were also made with
adjustments to the water content differences between egg whites and yolks. Unadjusted bread formulations made
with higher percentages of egg whites were larger in volume (2.60 cm3/g) compared to breads made with all egg
yolk (2.07 cm3/g). Breads with higher levels of egg whites also had more consistent cell structure (10.7 ± 1.65
cells/cm2 vs 8.1 ± 0.72 cell/cm2, respectively), were moister and less firm, and had greater springiness than
breads with egg yolks. Differences at the air cell interface were observed in the protein/lipid interaction through
fluorescence microscopy and may contribute to lower volumes. Differences observed above were diminished
in adjusted formulas, but significant differences in multiple sensory and mechanical attributes still remained.
Although water content is an important factor, the addition of egg whites contributes to significant differences
compared to breads made with higher levels of egg yolks on several sensory, mechanical and structural attributes.
This study quantitatively confirms the characteristics contributed to egg whites versus egg yolks in gluten-free
breads
Carbene character in a series of neutral PC carbene P cobalt(I) complexes: Radical carbenes versus nucleophilic carbenes
No full textCobalt(I) complexes supported by a series of PCcarbeneP pincer ligands of varying donicity, differing in the aryl group linking the phosphine arms with the anchoring carbon donor, are described. Addition of the proligands to cobalt bromide results in the formation of a series of cobalt(II) tetrahedral complexes, Ln-1, which serve as excellent precursors to the corresponding PCalkylP and PCcarbeneP complexes. The square-planar cobalt PCcarbeneP complexes L2R-3-X (X = Cl, Br) are readily synthesized by addition of a bulky aryloxide radical to the corresponding PCalkylP complex L1-2-Br, via addition of L2R to ClCo(PPh3)3 in the presence of trityl radical, or by addition of NaHBEt3 and trityl radical to isolated L2R-1. For the L2NMe2 PCcarbeneP complexes, salt metathesis reactions with CsOH·H2O, LiCH2TMS, or LiNH2 result in the corresponding hydroxo, alkyl, and amine complexes L2NMe2-3-R (R = OH, CH2TMS, NH2). Reaction of L2NMe2-3-OH with benzoic acid affords the κ2-O2CPh derivative The nature of the carbene bond in either ligand platform and the effects of the X-type capping ligand on the Co═C bond are explored using CASSCF and CASPT2 calculations and show that triplet structures are relatively more stable for the less electron donating ligand L1 while singlet Co(I) carbenes dominate for the more electron rich L2 derivatives. For L2NMe2 complexes, the effect of the trans ligand X was also probed. π donors imbue the carbene with singlet character, while the strongly σ donating alkyl derivative exhibits significant triplet character
Comparison of therapeutic antibiotics, probiotics, and synthetic CpG-ODNs for protective efficacy against Escherichia coli lethal infection and impact on the immune system in neonatal broiler chickens
No full textThe poultry industry needs alternatives to antibiotics, as there are growing public concerns about the emergence of antimicrobial resistance owing to antimicrobial use in animal production. We have reported that the administration of neonatal chicks with synthetic DNA oligodeoxynucleotides containing unmethylated cytosine guanine dinucleotide (CpG) motifs (CpG-ODN) can protect against bacterial pathogens in chickens. The objective of this study was to compare the immunoprotective effects of CpG-ODN and probiotics against Escherichia coli infection vs. commonly used therapeutic antibiotics. Day-old broiler chicks were divided into five groups (n = 35/group; 30 for the challenge experiment and 5 for the flow cytometry analysis). The chicks in Group 1 received a single dose of CpG-ODN by the intramuscular route on day 4 (D4) posthatch (PH), and Group 2 received drinking water (DW) with a probiotic product (D1–D15 PH, DW). The Group 3 chicks received tetracycline antibiotics during D9–D13 in DW; the Group 4 chicks got sodium sulfamethazine on D9, D10, and D15 PH in DW; and the Group 5 chicks were administered intramuscular (IM) saline D4 PH, DW. We challenged all the groups (n = 30/group) with E. coli (1 × 105 or 1 × 106 colony-forming units/bird) on D8 PH through the subcutaneous route. Our data demonstrated that the CpG-ODNs, but not the probiotics, could protect neonatal broiler chickens against lethal E. coli septicemia, as would the tetracycline or sodium sulfamethazine. The flow cytometry analysis (n = 5/group) revealed enrichment of immune cells in the CpG-ODN group and a marked decrease in macrophages and T-cell numbers in antibiotics-treated groups, indicating immunosuppressive effects. Our data showed that, like therapeutic antibiotics, CpG-ODNs reduced clinical signs, decreased bacterial loads, and induced protection in chicks against E. coli septicemia. Unlike therapeutic antibiotics-induced immunosuppressive effects, CpG-ODN caused immune enrichment by increasing chicken immune cells recruitment. Furthermore, this study highlights that, although therapeutic antibiotics can treat bacterial infections, the ensuing immunosuppressive effects may negatively impact the overall chicken health
CFD based analysis of 3D printed nasopharyngeal swabs for COVID-19 diagnostics
No full textBackground and Objective
Additive manufacturing of nasopharyngeal (NP) swabs using 3D printing technology presents a viable alternative to address the immediate shortage problem of standard flock-headed swabs for rapid COVID-19 testing. Recently, several geometrical designs have been proposed for 3D printed NP swabs and their clinical trials are already underway. During clinical testing of the NP swabs, one of the key criteria to compare the efficacy of 3D printed swabs with traditional swabs is the collection efficiency. In this study, we report a numerical framework to investigate the collection efficiency of swabs utilizing the computational fluid dynamics (CFD) approach.
Methods
Three-dimensional computational domain comprising of NP swab dipped in the liquid has been considered in this study to mimic the dip test procedure. The volume of fluid (VOF) method has been employed to track the liquid-air interface as the NP swab is pulled out of the liquid. The governing equations of the multiphase model have been solved utilizing finite-volume-based ANSYS Fluent software by imposing appropriate boundary conditions. Taguchi's based design of experiment analysis has also been conducted to evaluate the influence of geometric design parameters on the collection efficiency of NP swabs. The developed model has been validated by comparing the numerically predicted collection efficiency of different 3D printed NP swabs with the experimental findings.
Results
Numerical predictions of the CFD model are in good agreement with the experimental results. It has been found that there prevails huge variability in the collection efficiency of the 3D printed designs of NP swabs available in the literature, ranging from 2 µl to 120 µl. Furthermore, even the smallest alteration in the geometric design parameter of the 3D printed NP swab results in significant changes in the amount of fluid captured.
Conclusions
The proposed framework would assist in quantifying the collection efficiency of the 3D printed designs of NP swabs, rapidly and at a low cost. Moreover, we demonstrate that the developed framework can be extended to optimize the designs of 3D printed swabs to drastically improve the performances of the existing designs and achieve comparable efficacy to that of conventionally manufactured swabs
Development of a predictive model for bovine leukemia virus proviral load
No full textBackground
There is currently no commercially available method in Canada to identify bovine leukemia virus (BLV)-positive cows with high proviral load (PVL).
Objectives
First, develop a model to predict PVL using common, commercially available, cost-effective diagnostic tests. Second, investigate the relationship between lymphocyte count and PVL in BLV-positive cows.
Animals
A total of 339 BLV-positive and 62 BLV-seronegative cows on 15 dairy farms.
Methods
Cross-sectional study. Blood and milk samples were collected from all lactating BLV-positive cows on each farm and 5 to 10 BLV-seronegative cows depending on herd size. Blood and milk samples were tested for anti-BLV antibodies using enzyme-linked immunosorbent assay (ELISA). Complete blood counts were performed on blood samples, and standard components analyses were obtained for milk samples. Proviral load was determined by quantitative polymerase chain reaction for each cow.
Results
The inverse of lymphocyte count, the square of the inverse of lymphocyte count, and milk ELISA percent positivity were positively associated with increasing PVL in BLV-positive cows. For BLV-positive cows, lymphocyte count >5.2 × 109/L predicted a high PVL (BLV:Bovine DNA of >1 in blood) with a sensitivity of 92.4% and a specificity of 79.8%. For BLV-positive cows, white blood cell count >10.8 × 109/L predicted a high PVL, with a sensitivity of 85.5% and a specificity of 83.6%.
Conclusions and Clinical Importance
Based on these results, producers can implement commonly available diagnostic tests to identify cows with high probability of having high PVL, which may help in designing effective disease control strategies for BLV-positive herds.Agriculture and Agri-Food CanadaDairy Farmers of New Brunswick-Producteurs laitiers du Nouveau-BrunswickDairy Farmers of Nova ScotiaDairy Farmers of Prince Edward Islan
In the literature - review: Total and ionized hypercalcemia in cats with chronic kidney disease
No full textParental knowledge, self-confidence, and usability evaluation of a web-based infographic for pediatric concussion: Multimethod study
No full textBackground:
Concussions, which are known as mild traumatic brain injuries, are complex injuries caused by direct or indirect blows to the head and are increasingly being recognized as a significant public health concern for children and their families. Previous research has identified few studies examining the efficacy of educational interventions on parental concussion knowledge. The aim of this research was to actively work together with children who have experienced a concussion and their parents to develop, refine, and evaluate the usability of a web-based infographic for pediatric concussion.
Objective:
The objective of this study was to report on the usability of the infographic, parental knowledge, and self-confidence in pediatric concussion knowledge before and after exposure to the infographic.
Methods:
A multiphase, multimethod research design using patient engagement techniques was used to develop a web-based infographic. For this phase of the research (usability, knowledge, and confidence evaluation), parents who could communicate in English were recruited via social media platforms and invited to complete web-based questionnaires. Electronic preintervention and postintervention questionnaires were administered to parents to assess changes to concussion knowledge and confidence after viewing the infographic. A usability questionnaire with 11 items was also completed.
Results:
A web-based, infographic was developed. The infographic is intended for parents and children and incorporates information that parents and children identified as both wants and needs about concussion alongside the best available research evidence on pediatric concussion. A total of 31 surveys were completed by parents. The mean scores for each item on the usability surveys ranged from 8.03 (SD 1.70) to 9.26 (SD 1.09) on a 10-point Likert scale, indicating that the usability components of the infographic were largely positive. There was no statistically significant difference between preintervention and postintervention knowledge scores (Z=−0.593; P=.55; both preintervention and postintervention knowledge scores had a median of 9 out of 10). In contrast, there was a statistically significant difference between preintervention (mean 3.9/5, SD 0.56) and postintervention (mean 4.4/5, SD 0.44) confidence in knowledge scores (t30=−5.083; P<.001).
Conclusions:
Our results demonstrate that parents positively rated a web-based, infographic for pediatric concussion. In addition, although there was no statistically significant difference overall in parents’ knowledge scores before and after viewing the infographic, their confidence in their knowledge did significantly increase. These results suggest that using a web-based infographic as a knowledge translation intervention may be useful in increasing parents’ confidence in managing their child’s concussion.Canadian Institutes of Health Research Foundatio