Glacier motion responds dynamically to changing meltwater inputs, but the multi-decadal response of basal sliding to climate remains poorly constrained due to its sensitivity across multiple timescales. Observational records of glacier motion provide critical benchmarks to decode processes influencing glacier dynamics, but multi-decadal records that precede satellite observation and modern warming are rare. Here we present a record of motion in the ablation zone of Saskatchewan Glacier that spans seven decades. We combine in situ and remote-sensing observations to inform a first-order glacier flow model used to estimate the relative contributions of sliding and internal deformation on dynamics. We find a significant increase in basal sliding rates between melt-seasons in the 1950s and those in the 1990s and 2010s and explore three process-based explanations for this anomalous behavior: (i) the glacier surface steepened over seven decades, maintaining flow-driving stresses despite sustained thinning; (ii) the formation of a proglacial lake after 1955 may support elevated basal water pressures; and (iii) subglacial topography may cause dynamic responses specific to Saskatchewan Glacier. Although further constraints are necessary to ascertain which processes are of greatest importance for Saskatchewan Glacier's dynamic evolution, this record provides a benchmark for studies of multi-decadal glacier dynamics.

Maintenance is an essential aspect to keeping production facilities running and safe. However, without an overview of the maintenance impact on production, gaining clarification of the impact of maintenance is difficult. This paper introduces modularization of maintenance based on the dimensions of maintenance: physical, action, and process. The approach is applied in a case study where maintenance decisions are improved and faster than prior to the introduction of the modularized maintenance.

The challenge of user requirements for maintenance scheduling design in large asset-intensive industries suffers from lack of academic and empirical studies. Therefore, using a representative case study, this paper aims to: (1) identify the current practices and complex scheduling requirements; (2) propose a design support tool to optimize the maintenance scheduling process; and (3) report the gained benefits. The results reveal that the proposed tool can decrease the resource requirements, increase the capacity utilization, and reduce the cost while addressing the complex user requirements.

It is important to be able to compare and evaluate different solutions early in development. This paper proposes a method for structuring historical data into a data model that can support the evaluation of new design concepts. The data is contextualized by linking it to a hierarchical decomposition of existing products. Two case studies were conducted to evaluate the value of using historical data when evaluating new concepts. The cases confirm that the proposed method is useful for evaluation of new concepts.

Introduction: Epidemiologic and modeling studies suggest that between 45 and 70% of individuals with chronic hepatitis C virus (HCV) infection in Canada remain undiagnosed. The Canadian Association for the Study of the Liver (CASL) recommends one-time screening of baby boomers (1945-1975). Screening programs in the US have shown a very high prevalence of previously undiagnosed HCV among patients seen in the emergency department (ED). We sought to assess the feasibility of implementing a targeted birth-cohort HCV screening program in a Canadian ED setting. Methods: Patients born from 1945 to 1975 presenting to the ED of a downtown Toronto hospital were offered HCV testing. Patients with life-threatening conditions, unable to provide verbal consent in English or intoxication were excluded. Blood samples were collected by finger prick on Dried Blood Spot (DBS) collection cards and tested for anti-HCV antibody with reflex to HCV RNA. Patients with positive HCV RNA were referred to a liver specialist. Results: During a 27-month period (July 2017 - Sept 2019), 8363 patients in the birth cohort presented to the ED during daytime hours. 80% (6714) met eligibility criteria, and 48.4% (3247) were offered testing. Screening was performed by non-medical staff (mean 8/day, median spots on DBS 4). 345 (10.6%) had been previously tested, and 639 (19.7%) declined. 2136 (65.8%) patients underwent testing: median age 58.4 years (40-82), 1117 male (52.3%). Of these, 45 patients (2.1%; 95% CI 1.5%-2.7%) were anti-HCV positive: 32 (76.2%) were HCV RNA positive, 10 (23.8%) negative and 3 not done due to inadequate DBS sample. 26 patients (81.3%) were linked to care and 3 (9.4%) lost to follow-up. HCV prevalence in the ED was significantly higher than the general Canadian population (2.1% vs 0.7%; p < 0.0001) but much lower than reported rates in American EDs (2.1% vs 10.3%; p < 0.0001). Conclusion: Acceptance of HCV screening in the ED birth cohort was high and easily performed using DBS to ensure the majority of positive samples were tested for HCV RNA. Challenges included implementation that limited number of people tested, and linkage to care for HCV positive patients. HCV prevalence among this ED birth cohort was higher than the general population but lower than seen in the ED in the US. This may in part be due to exclusion of individuals with more severe medical issues, refusal by higher risk subgroups, or population and healthcare system differences between countries.

In the mink industry, feed costs are the largest variable expense and breeding for feed efficient animals is warranted. Implementation of selection for feed efficiency must consider the relationships between feed efficiency and the current selection traits BW and litter size. Often, feed intake (FI) is recorded on a cage with a male and a female and there is sexual dimorphism that needs to be accounted for. Study aims were to (1) model group recorded FI accounting for sexual dimorphism, (2) derive genetic residual feed intake (RFI) as a measure of feed efficiency, (3) examine the relationship between feed efficiency and BW in males (BWM) and females (BWF) and litter size at day 21 after whelping (LS21) in Danish brown mink and (4) investigate direct and correlated response to selection on each trait of interest. Feed intake records from 9574 cages, BW records on 16 782 males and 16 875 females and LS21 records on 6446 yearling females were used for analysis. Genetic parameters for FI, BWM, BWF and LS21 were obtained using a multivariate animal model, yielding sex-specific additive genetic variances for FI and BW to account for sexual dimorphism. The analysis was performed in a Bayesian setting using Gibbs sampling, and genetic RFI was obtained from the conditional distribution of FI given BW using genetic regression coefficients. Responses to single trait selection were defined as the posterior distribution of genetic superiority of the top 10% of animals after conditioning on the genetic trends. The heritabilities ranged from 0.13 for RFI in females and LS21 to 0.59 for BWF. Genetic correlations between BW in both sexes and LS21 and FI in both sexes were unfavorable, and single trait selection on BW in either sex showed increased FI in both sexes and reduced litter size. Due to the definition of RFI and high genetic correlation between BWM and BWF, selection on RFI did not significantly alter BW. In addition, selection on RFI in either sex did not affect LS21. Genetic correlation between sexes for FI and BW was high but significantly lower than unity. The high correlations across sex allowed for selection on standardized averages of animals’ breeding values (BVs) for RFI, FI and BW, which yielded selection responses approximately equal to the responses obtained using the sex-specific BVs. The results illustrate the possibility of selecting against RFI in mink with no negative effects on BW and litter size.

Recent data suggest that organic broilers often score worse on footpad lesions than conventional broilers but also that the current scoring of organic broiler feet may be misleading. In order to characterise footpad lesions in organic broilers, this study assessed and compared footpad lesions in a sample of 2987 conventional and 3578 organic broiler feet obtained from a large Danish abattoir during summer and winter. The feet were scored according to two scoring systems: the modified Danish surveillance scoring system and a histopathology-based new scoring system specifically developed to target the ability to differentiate between broiler feet with hyperkeratosis and ulcers. For both systems, all broiler feet with visible lesions were cross-sectionally incised. Significant differences between the two production systems were found for both scoring systems (χ2 = 710; P < 0.001 and χ2 = 247; P < 0.001 for the new and the surveillance systems, respectively), showing that a larger proportion of the organic feet compared to conventional feet – summer and winter – exhibited signs of hyperkeratosis. In addition, a smaller fraction of the organic feet than of the conventional feet were given the outermost scores, that is, normal or ulcerated; 13.4% v. 25.3% broiler feet were given score 0 for organic v. conventional production systems, respectively (χ2 = 152; P < 0.001), and 18.4% v. 23.8% feet were given score 4 for organic v. conventional production systems, respectively (χ2 = 308; P < 0.001). Thus, the results suggest that surveillance scoring systems such as the one used in Denmark are useful for the examination of footpad lesions in broilers from both types of production systems. However, the results have also raised attention to a typical characteristic of the feet of organic broilers, that is, profound hyperkeratosis, which may underlie potential misclassifications in surveillance scoring systems like the one used in Denmark. Among the possible solutions to this challenge to the correctness and fairness of the scoring system are improved procedures (such as mandatory incision), training of technicians and calibration of results (especially for the organic footpads).

Green rusts, GRs, can act as both sorbents and reductants towards selected pollutants. Organo-GRs are expected to combine these properties with a high affinity for hydrophobic substances. A novel organo-GR, GRLAS, was synthesized by incorporating a mixture of linear alkylbenzenesulphonates (LAS) into the interlayer space of synthetic sulphate green rust, GRSO4 . Mössbauer analysis of GRLAS indicates that the structure of the organo-GR is very similar to that of the initial GRSO4 with regard to the FeII/FeIII ratio and local coordination of Fe atoms. X-ray diffraction demonstrates that the GRLAS formed was well ordered, although a mixture of surfactant was used for intercalation. The basal spacings of the GRLAS and the kinetics of the ion-exchange process were dependent on the initial surfactant loading; basal spacings of ~2.85 nm were obtained at LAS solution concentrations >10 mM. The ratio LASadsorbed/SO4 2– desorbed significantly exceeded the stoichiometric ratio of 2 during the initial part of the ion-exchange process (t = 5 h). However, this ratio was reached progressively with time. GRSO4 preferentially sorbed LAS homologues with long alkyl chains over short ones. Carbon tetrachloride was successfully adsorbed into GRLAS. The adsorption isotherm was linear with a distribution coefficient, Kd , of 505±19 litre kg–1.

Intrinsic surface acidity constants (Kal intr, Ka2 intr) and surface complexation constant for adsorption of orthosilicate onto synthetic ferrihydrite (Ksi for the complex ≡FeOSi(OH)3) have been determined from acid/base titrations in 0.001-0.1 M NaClO4 electrolytes and silicate adsorption experiments in 0.01 M NaNOi electrolyte (pH 3-6). The surface equilibrium constants were calculated according to the two-layer model by Dzombak ' Morel (1990). Near equilibrium between protons/hydroxyls in solution and the ferrihydrite surface was obtained within minutes while equilibration with silicate required days-weeks, both reactions probably being diffusion controlled. Applying the values for specific surface area and site densities for ferrihydrite used by Dzombak ' Morel (1990) (600 m2 g–1, 3.4 μmole m–2) the constants pKal intr = 6.93 ± 0.12, pKa2 intr = 8.72 ± 0.17 and log Ksi = 3.62 were calculated by using the FITEQL optimization routine. Use of the specific surface area actually measured (269 m2 g-1) gave a poorer fit of the experimental data. Due to the slow adsorption of silicate and hence long shaking times, changes in the surface characteristics of the ferrihydrite seem to take place, probably a decrease in the concentration of surface sites. Adsorption isotherms calculated using the derived equilibrium constants showed that approximately twice the amount of silicate was adsorbed at pH 5 compared with pH 3.

Infrared spectroscopy of silica adsorbed to ferrihydrite showed Si-O stretching absorption maxima in the range 940-960 cm-1. The shift of the absorption maximum to higher wavenumbers with increasing amount of silicate adsorbed is probably due to an increase in the frequency of Si-O-Si bonds between orthosilicate adsorbed at adjacent sites. Small amounts of goethite were identified in the adsorption products.

Coinfection with human immunodeficiency virus (HIV) and viral hepatitis is associated with high morbidity and mortality in the absence of clinical management, making identification of these cases crucial. We examined characteristics of HIV and viral hepatitis coinfections by using surveillance data from 15 US states and two cities. Each jurisdiction used an automated deterministic matching method to link surveillance data for persons with reported acute and chronic hepatitis B virus (HBV) or hepatitis C virus (HCV) infections, to persons reported with HIV infection. Of the 504 398 persons living with diagnosed HIV infection at the end of 2014, 2.0% were coinfected with HBV and 6.7% were coinfected with HCV. Of the 269 884 persons ever reported with HBV, 5.2% were reported with HIV. Of the 1 093 050 persons ever reported with HCV, 4.3% were reported with HIV. A greater proportion of persons coinfected with HIV and HBV were males and blacks/African Americans, compared with those with HIV monoinfection. Persons who inject drugs represented a greater proportion of those coinfected with HIV and HCV, compared with those with HIV monoinfection. Matching HIV and viral hepatitis surveillance data highlights epidemiological characteristics of persons coinfected and can be used to routinely monitor health status and guide state and national public health interventions.

Introduction: In order to achieve the best possible outcomes for patients requiring resuscitation (PRRs) in the emergency department (ED), health care providers (HCPs) must provide an efficient, multi-disciplinary and coordinated response. A quality improvement (QI) project was undertaken to improve HCP response to PRRs at two tertiary care hospital EDs in Toronto. Methods: We conducted a before-and-after mixed-method survey to evaluate the perception of the adequacy of HCP response and clarity of HCP role when responding to PRRs. The results were compared using the Chi-square test. Qualitative responses to the first survey were also used to inform the development of the QI project. Through interviews of key stakeholders and with continuous input from front-line ED HCPs, a multi-disciplinary team modified the ED resuscitation protocol. This included standardized pre-hospital communication form with paramedics, ED-wide overhead announcement of ‘Code Resus’, dedicated HCPs assigned to respond to PRRs, and specific duties assigned to each responder. Change initiatives were reinforced through education and posters in the ED. Six months after implementation, a second survey was conducted to evaluate the sustained effects of the intervention. Results: Baseline measures indicated that 16 of 52 (30.8%) nurses surveyed believed their role was often or always apparent to themselves and others when they attended to a PRR (on a 5-point rating scale). This proportion increased to 35 of 55 (63.6%) nurses in the post-implementation survey (p < 0.001). Regarding adequacy of the number of HCPs responding to PRRs, 17 of 39 (43.6%) physicians and 23 of 53 (43.4%) nurses surveyed thought the appropriate number of HCPs responded to PRRs; the remainder thought that there were too few or too many HCPs. In the post-implementation survey, 34 of 41 (82.9%) physicians (p < 0.001) and 36 of 56 (64.3%) nurses (p = 0.029) surveyed felt that the appropriate number of HCPs attended to PRRs. Conclusion: Using a quality improvement approach, we identified and quantified perceived deficiencies in HCP response to PRRs in the ED. Through feedback-based modifications of the ED resuscitation protocol and by engaging HCP stakeholders, change initiatives were implemented to improve HCP response. As a result, this project achieved significant and sustained improvements in HCPs’ perceived response to PRRs.

Interfacial dislocations (IDs) and half-loop arrays (HLAs) present in theepilayers of 4H-SiC crystal are known to have a deleterious effect on deviceperformance. Synchrotron X-ray Topography studies carried out on n-type 4H-SiCoffcut wafers before and after epitaxial growth show that in many cases BPDsegments in the substrate are responsible for creating IDs and HLAs during CVDgrowth. This paper reviews the behaviors of BPDs in the substrate during theepitaxial growth in different cases: (1) screw-oriented BPD segmentsintersecting the surface replicate directly through the interface during theepitaxial growth and take part in stress relaxation process by creating IDs andHLAs (Matthews-Blakeslee model [1] ); (2) non-screw oriented BPD half loopintersecting the surface glides towards and replicates through the interface,while the intersection points convert to threading edge dislocations (TEDs) andpin the half loop, leaving straight screw segments in the epilayer and thencreate IDs and HLAs; (3) edge oriented short BPD segments well below the surfaceget dragged towards the interface during epitaxial growth, leaving two longscrew segments in their wake, some of which replicate through the interface andcreate IDs and HLAs. The driving force for the BPDs to glide toward theinterface is thermal stress and driving force for the relaxation process tooccur is the lattice parameter difference at growth temperature which resultsfrom the doping concentration difference between the substrate and epilayer.

Determination of appropriate nutritional requirements is essential to optimize the productivity and longevity of lactating sows. The current recommendations for requirements do not consider the large variation between animals. Therefore, the aim of this study was to determine the amino acid recommendations for lactating sows using a stochastic modeling approach that integrates population variation and uncertainty of key parameters into establishing nutritional recommendations for lactating sows. The requirement for individual sows was calculated using a factorial approach by adding the requirement for maintenance and milk. The energy balance of the sows was either negative or zero depending on feed intake being a limiting factor. Some parameters in the model were sow-specific and others were population-specific, depending on state of knowledge. Each simulation was for 1000 sows repeated 100 times using Monte Carlo simulation techniques. BW, back fat thickness of the sow, litter size (LS), average litter gain (LG), dietary energy density and feed intake were inputs to the model. The model was tested using results from the literature, and the values were all within ±1 s.d. of the estimated requirements. Simulations were made for a group of low- (LS=10 (s.d.=1), LG=2 kg/day (s.d.=0.6)), medium- (LS=12 (s.d.=1), LG=2.5 kg/day (s.d.=0.6)) and high-producing (LS=14 (s.d.=1), LG=3.5 kg/day (s.d.=0.6)) sows, where the average requirement was the result. In another simulation, the requirements were estimated for each week of lactation. The results were given as the median and s.d. The average daily standardized ileal digestible (SID) protein and lysine requirements for low-, medium- and high-producing sows were 623 (CV=2.5%) and 45.1 (CV=4.8%); 765 (CV=4.9%) and 54.7 (CV=7.0%); and 996 (CV=8.5%) and 70.8 g/day (CV=9.6%), respectively. The SID protein and lysine requirements were lowest at week 1, intermediate at week 2 and 4 and the highest at week 3 of lactation. The model is a valuable tool to develop new feeding strategies by taking into account the variable requirement between groups of sows and changes during lactation. The inclusion of between-sow variation gives information on safety margins when developing new dietary recommendations of amino acids and protein for lactating sows.

A review is presented of Synchrotron X-ray Topography and KOH etching studies carried out on n type 4H-SiC offcut substrates before and after homo-epitaxial growth to study defect replication and strain relaxation processes and identify the nucleation sources of both interfacial dislocations (IDs) and half-loop arrays (HLAs) which are known to have a deleterious effect on device performance. We show that these types of defects can nucleate during epilayer growth from: (1) short segments of edge oriented basal plane dislocations (BPDs) in the substrate which are drawn by glide into the epilayer; and (2) segments of half loops of BPD that are attached to the substrate surface prior to growth which also glide into the epilayer. It is shown that the initial motion of the short edge oriented BPD segments that are drawn from the substrate into the epilayer is caused by thermal stress resulting from radial temperature gradients experienced by the wafer whilst in the epi-chamber. This same stress also causes the initial glide of the surface half-loop into the epilayer and through the advancing epilayer surface. These mobile BPD segments provide screw oriented segments that pierce the advancing epilayer surface that initially replicate as the crystal grows. Once critical thickness is reached, according to the Mathews-Blakeslee model [1], these screw segments glide sideways under the action of the mismatch stress leaving IDs and HLAs in their wake. The origin of the mismatch stress is shown to be associated with lattice parameter differences at the growth temperature, arising from the differences in doping concentration between substrate and epilayer.