Climate data for building simulations with urban heat island effects and nature-based solutions.

As cities face a changing climate, buildings will be subjected to increasing energy demand, heat stress, thermal comfort issues, and decreased service life. Therefore, evaluating building performance under climate change is essential for maintaining sustainable and resilient communities. To better prepare building simulation climate data with urban effects, a computationally efficient approach is used to generate "urbanized" data, where the city's unique signature is obtained through the dynamic Weather Research and Forecasting model for the Ottawa, Canada region. We demonstrate this process using existing climate data and extend it to prepare projections for scenarios where nature-based solutions, such as increased greenery and albedo, were implemented. The data consists of several 31-year time series of climate variables such as temperature, humidity, wind speed and direction, pressure, cloud cover, and precipitation over different global warming thresholds. Such a dataset allows building practitioners to evaluate building performance under both historical and future climate conditions, as well as to evaluate the impacts of nature-based solutions to mitigate future climate change risks.

Typical and extreme weather datasets for studying the resilience of buildings to climate change and heatwaves.

We present unprecedented datasets of current and future projected weather files for building simulations in 15 major cities distributed across 10 climate zones worldwide. The datasets include ambient air temperature, relative humidity, atmospheric pressure, direct and diffuse solar irradiance, and wind speed at hourly resolution, which are essential climate elements needed to undertake building simulations. The datasets contain typical and extreme weather years in the EnergyPlus weather file (EPW) format and multiyear projections in comma-separated value (CSV) format for three periods: historical (2001-2020), future mid-term (2041-2060), and future long-term (2081-2100). The datasets were generated from projections of one regional climate model, which were bias-corrected using multiyear observational data for each city. The methodology used makes the datasets among the first to incorporate complex changes in the future climate for the frequency, duration, and magnitude of extreme temperatures. These datasets, created within the IEA EBC Annex 80 "Resilient Cooling for Buildings", are ready to be used for different types of building adaptation and resilience studies to climate change and heatwaves.

Technical assessment of shear bond strength at ceramo-alloy interface after various surface treatment combinations and application of metal bonding agent.

BACKGROUND: Bonding between metal and ceramic is one of the most important aspects of a successful prosthesis. Various methods have been recommended for preparing the metal surface to enhance the bond between metal and ceramic including the use of a metal bonding agent. OBJECTIVE: This study aims to evaluate and compare the shear bond strength of the metal-ceramic (M-C) interface after combinations of various surface treatments including the application of a metal bonding agent. METHOD: 40 Ni-Cr alloy specimens were made and divided into 4 groups of 10 each based on the combination of surface treatments. Sandblasting, surface grinding, and Oxidation heat treatment (OHT) were performed on specimens from Group 1 (Control). In addition, Group 2 specimens received ultrasonic cleaning, Group 3 steam cleaning, and Group 4 metal bonding agent application. Following surface treatments on all specimens, porcelain build-up was performed, and shear bond strength was tested in a Digital Universal testing machine. The statistical tests used were independent t-test and ANOVA. RESULTS: Results revealed that Group 4 specimens had the highest mean value of shear bond strength of 39.087 MPa while Group 3 specimens showed the least mean shear bond strength of 18.154 MPa with highly statistically significant results (p< 0.001). CONCLUSION: The surface treatments and application of bonding agent to metal prior to porcelain application resulted in increased shear bond strength of the metal-ceramic interface.

A Quantitative Assessment to Compare the Dimensions of the Alveolar Ridge Width Using Different Techniques for Implant Placement.

BACKGROUND: The success of any dental implant surgery depends on the correct diagnosis and treatment planning. PURPOSE: The aim of this study was to compare the dimensions of the alveolar ridge width using different techniques for implant placement. MATERIALS AND METHODS: The study involved 27 partially edentulous subjects aged 18-50, including males and females. In this study, the dimensions of the ridge were evaluated by ridge mapping on a cast, ridge mapping using a bone caliper, and ridge mapping with the help of an occlusal radiograph. All three methods were compared with ridge mapping by cone beam computed tomography (CBCT). For each subject, the site of implant placement was marked on the study model. Alveolar ridge measurement was done in the mouth by a bone caliper under local anesthesia with the help of a stent with a hole. Ridge mapping on a cast was done after sectioning the cast and marking with the help of a periodontal probe and stent. Ridge mapping was done on an occlusal radiograph by converting an acetate stent into a radiographic stent. Finally, CBCT was taken for each patient for ridge mapping. All four readings were tabulated. RESULTS: Comparing the mean alveolar ridge width of four groups, ANOVA showed significantly different alveolar ridge width among the groups (F=7.89, p<0.001). The validity (accuracy and precision) of ridge mapping on a cast, ridge mapping using a bone caliper, and occlusal radiograph against the CBCT (gold standard) was done using concordance correlation analysis. The concordance correlation analysis showed the highest association (ρ=0.8196) and precision (ϸ=82.61%) of ridge mapping using a bone caliper with CBCT. However, the accuracy of ridge mapping on a cast (Cb=99.42%) was the highest, followed by ridge mapping using a bone caliper (Cb=82.61%). The analysis concluded that both techniques are equivalent to CBCT and can be used interchangeably. CONCLUSION: The mean alveolar ridge width of the occlusal radiograph was the highest, followed by CBCT, ridge mapping on a cast, and ridge mapping using a bone caliper the least (occlusal radiograph > CBCT > ridge mapping on cast >ridge mapping using bone caliper). But at the same time, it can also be used interchangeably.

Comparative Evaluation of Compressive and Diametral Tensile Strength in Die Stone Reinforced With Different Types of Nanoparticles: An In Vitro Study.

AIM: To investigate the effect of different types of nanoparticles on the compressive strength (CS) and diametral tensile strength (DTS) of type IV dental stones. MATERIALS AND METHODS: A total of 100 specimens were made from the mould for all five groups. Four commercially available nanoparticles (aluminium oxide (Al2O3), silicon dioxide (SiO2), zinc oxide (ZnO), and zirconium oxide (ZrO2)) were used in this study in a concentration of 10%. CS and DTS tests were performed in a universal test machine. The data were statistically analysed using ANOVA and Student's t-test. RESULTS: The interaction between nanoparticles and the type of dental stone was found to be statistically significant (p < 0.05). CS and DTS values decreased by adding all four nanoparticles. The lowest CS and DTS were observed in 10% ZnO nanoparticles when added to type IV dental stone. CONCLUSION: It was concluded that the addition of nanoparticles (Al2O3, SiO2, ZnO, and ZrO2) to die stone significantly decreased the CS and DTS for all groups. Among all groups, the incorporation of 10% ZrO2 nanoparticles (group E) to die stone showed significantly less decrease in CS and DTS compared to Al2O3, SiO2, and ZnO. Incorporation of ZnO nanoparticles, on the other hand, showed a significantly more amount of decrease in the CS and DTS compared to Al2O3, SiO2, and ZrO2.

Evolution of the local climate in Montreal and Ottawa before, during and after a heatwave and the effects on urban heat islands.

The heatwave event to which the Ontario-Quebec area was subjected in 2018 resulted in significant morbidity and mortality. In this study, an investigation was conducted on how this heatwave affected the respective urban heat islands (UHIs) in Montreal and Ottawa. The modelled urban climates were compared before, during and after the heatwave using a Weather Research and Forecast (WRF) model having a 1 km spatial resolution. The UHI was calculated using two methods. As a first method, the "rural-ring" method was used to calculate the UHI in regard to temperature differences between urban and surrounding rural areas. The second method used the "urban-increment" approach where simulation results were compared to another simulation in which urban cells are replaced by croplands. Results show that urban land can raise temperatures by up to 12 °C at surfaces and 6 °C in the near-surface air. A synoptic anticyclone in the lower atmosphere was responsible for the heatwave, although both cities were located in areas peripheral to the anticyclone. During the heatwave, precipitation at the initial stage of the event and low wind conditions largely varied the pattern of the UHI effect within each urban center. The UHI was generally unchanged or even reduced during this heatwave, but there was substantial diurnal variation. Around noon and in the afternoon, the UHI was amplified by up to 3 °C, whereas it was suppressed or even negative at sunrise.

Increased delay from initial concern to diagnosis of autism spectrum disorder and associated health care resource utilization and cost among children aged younger than 6 years in the United States.

BACKGROUND: Prolonged delays between first caregiver concern and autism spectrum disorder (ASD) diagnosis have been reported, but associations between length of time to diagnosis (TTD) and health care resource utilization (HCRU) and costs have not been studied in a large sample of children with ASD. OBJECTIVE: To address these informational gaps in the ASD diagnostic pathway. METHODS: This retrospective, observational, single cohort analysis of Optum's administrative claims data from January 1, 2011, to December 31, 2020, included commercially insured children who had 2 or more claims for an ASD diagnosis (earliest diagnosis designated as the index date), were between the ages of older than 1.5 years and 6 years or younger at index date, and were continuously enrolled for up to 48 months before and for 12 months after the index date. Two cohorts (between the ages of older than 1.5 years and 3 years or younger and between the ages of older than 3 years and 6 years or younger at ASD diagnosis) were divided into shorter (less than median) and longer (greater than or equal to median) TTD around each cohort median TTD calculated from the first documented ASD-related concern to the earliest ASD diagnosis, because TTD may vary by age at diagnosis. This exploratory analysis compared all-cause and ASD-related HCRU and costs during a 12-month period preceding ASD diagnosis among children with shorter vs longer TTD. RESULTS: 8,954 children met selection criteria: 4,205 aged 3 years or younger and 4,749 aged older than 3 years at diagnosis, with median TTD of 9.5 and 22.1 months, respectively. In the year preceding ASD diagnosis, children with longer TTD in both age cohorts experienced a greater number of all-cause and ASD-related health care visits compared with those with shorter TTD (mean and median number of office or home visits were approximately 1.5- and 2-fold greater in longer vs shorter TTD groups; P < 0.0001). The mean all-cause medical cost per child in the year preceding ASD diagnosis was approximately 2-fold higher for those with longer vs shorter TTD ($5,268 vs $2,525 in the younger and $5,570 vs $2,265 in the older cohort; P < 0.0001 for both). Mean ASD-related costs were also higher across age cohorts for those with longer vs shorter TTD ($2,355 vs $859 in the younger and $2,351 vs $1,144 in the older cohort; P < 0.0001 for both). CONCLUSIONS: In the year prior to diagnosis, children with longer TTD experienced more frequent health care visits and greater cost burden in their diagnostic journey compared with children with shorter TTD. Novel diagnostic approaches that could accelerate TTD may reduce costs and HCRU for commercially insured children. DISCLOSURES: This study was funded by Cognoa, Inc. Optum received funding from Cognoa to conduct this study. Dr Salomon is an employee and holds stock options of Cognoa, Inc. Dr Campbell was an employee of Cognoa, Inc., at the time this study was conducted. Dr Duhig was an employee of Cognoa, Inc., at the time the study was conducted and holds stock options. Dr Vu, Ms Kruse, Mr Gaur, and Ms Gupta are employees and/or stockholders of Optum. Dr Tibrewal was an employee of Optum at the time the research for this study was conducted. Dr Taraman is an employee and holds stock options of Cognoa, Inc., receives consulting fees from Cognito Therapeutics, volunteers as a board member of the American Academy of Pediatrics California and Orange County Chapter, is a paid advisor for MI10 LLC, and owns stock options of NTX, Inc., and HandzIn.

Chemical plaque control - A brief review.

Dental plaque is a complex microbial population of bacterial and salivary polymers present on the tooth surface. It is understood that human diseases must be avoided and a high social concern for the population as a whole. The argument for the implementation of successful prevention measures is strong for life-threatening diseases or those with serious morbidity. However, regardless of seriousness, the case for avoiding any disease may be based on the belief that it is easier to be healthy than dead or sick. Thus plaque prevention is an efficient way to both treat and avoid periodontal diseases, it is an important component of gingival and periodontal diseases' primary management.

Analysis and modelling of surface Urban Heat Island in 20 Canadian cities under climate and land-cover change.

Surface Urban Heat Island (SUHI) is an urban climate phenomenon that is expected to respond to future climate and land-use land-cover change. It is important to further our understanding of physical mechanisms that govern SUHI phenomenon to enhance our ability to model future SUHI characteristics under changing geophysical conditions. In this study, SUHI phenomenon is quantified and modelled at 20 cities distributed across Canada. By analyzing MODerate Resolution Imaging Spectroradiometer (MODIS) sensed surface temperature at the cities over 2002-2012, it is found that 16 out of 20 selected cities have experienced a positive SUHI phenomenon while 4 cities located in the prairies region and high elevation locations have experienced a negative SUHI phenomenon in the past. A statistically significant relationship between observed SUHI magnitude and city elevation is also recorded over the observational period. A Physical Scaling downscaling model is then validated and used to downscale future surface temperature projections from 3 GCMs and 2 extreme Representative Concentration Pathways in the urban and rural areas of the cities. Future changes in SUHI magnitudes between historical (2006-2015) and future timelines: 2030s (2026-2035), 2050s (2046-2055), and 2090s (2091-2100) are estimated. Analysis of future projected changes indicate that 15 (13) out of 20 cities can be expected to experience increases in SUHI magnitudes in future under RCP 2.6 (RCP 8.5). A statistically significant relationship between projected future SUHI change and current size of the cities is also obtained. The study highlights the role of city properties (i.e. its size, elevation, and surrounding land-cover) towards shaping their current and future SUHI characteristics. The results from this analysis will help decision-makers to manage Canadian cities more efficiently under rapidly changing geophysical and demographical conditions.

Reinforcing Heat-cured Poly-methyl-methacrylate Resins using Fibers of Glass, Polyaramid, and Nylon: An in vitro Study.

INTRODUCTION: As civilization has progressed, there has been continued refinement of materials available for dental practice. The applications of resins have been extended to increased practical uses in numerous areas of prosthetic and restorative dentistry. Certain significant alterations in the technique of manipulation and nature of the dental product have influenced the range of application in dentistry. The present study was done to measure and compare the fracture strength of heat polymerized poly-methyl-methacrylate (PMMA) resin reinforced with fibers of glass, polyaramid, and nylon. MATERIALS AND METHODS: The present study was conducted in vitro on 40 PMMA denture base resin specimens. Specimens were divided into four subgroups with ten specimens each and tested for transverse strength using universal testing machine. RESULTS: In group I, the transverse strength mean value was 67.82 MPa. In group II, the transverse strength mean value was 59.47 MPa. In group III, the transverse strength mean value was 66.87 MPa, while in group IV, the transverse strength mean value was 66.47 MPa. CONCLUSION: Incorporation of 4% weight glass fibers in loose form significantly increased the transverse strength of denture base PMMA, while 4% of polyaramid fiber in random distribution significantly increased the transverse strength of denture base PMMA.

Association of Panton Valentine Leukocidin (PVL) genes with methicillin resistant Staphylococcus aureus (MRSA) in Western Nepal: a matter of concern for community infections (a hospital based prospective study).

BACKGROUND: Methicillin resistant Staphylococcus aureus (MRSA) is a major human pathogen associated with nosocomial and community infections. Panton Valentine leukocidin (PVL) is considered one of the important virulence factors of S. aureus responsible for destruction of white blood cells, necrosis and apoptosis and as a marker of community acquired MRSA. This study was aimed to determine the prevalence of PVL genes among MRSA isolates and to check the reliability of PVL as marker of community acquired MRSA isolates from Western Nepal. METHODS: A total of 400 strains of S. aureus were collected from clinical specimens and various units (Operation Theater, Intensive Care Units) of the hospital and 139 of these had been confirmed as MRSA by previous study. Multiplex PCR was used to detect mecA and PVL genes. Clinical data as well as antimicrobial susceptibility data was analyzed and compared among PVL positive and negative MRSA isolates. RESULTS: Out of 139 MRSA isolates, 79 (56.8 %) were PVL positive. The majority of the community acquired MRSA (90.4 %) were PVL positive (Positive predictive value: 94.9 % and negative predictive value: 86.6 %), while PVL was detected only in 4 (7.1 %) hospital associated MRSA strains. None of the MRSA isolates from hospital environment was found positive for the PVL genes. The majority of the PVL positive strains (75.5 %) were isolated from pus samples. Antibiotic resistance among PVL negative MRSA isolates was found higher as compared to PVL positive MRSA. CONCLUSION: Our study showed high prevalence of PVL among community acquired MRSA isolates. Absence of PVL among MRSA isolates from hospital environment indicates its poor association with hospital acquired MRSA and therefore, PVL may be used a marker for community acquired MRSA. This is first study from Nepal, to test PVL among MRSA isolates from hospital environment.

Electromyographic Evaluation of the Effect of Lined Dentures on Masticatory Muscle Activity in Edentulous Subjects.

AIM: The purpose of this study was to examine changes in relative electromyographic (EMG) activities of temporal and masseter muscles after relining the dentures with silicone and acrylic-resin based denture liners. MATERIALS AND METHODS: Conventional complete dentures were fabricated for 20 edentulous patients. One month after completing adjustments of the dentures, electromyography of the masseter and temporalis muscle during maximum intercuspation was recorded. The dentures were then relined with a silicone denture liner and after an adaptation period of one month, were again subjected for electromyographic evaluation. Further, the dentures were relined with acrylic denture liner and subjected to electromyographic evaluation. Data was analysed using Statistical Package for Social Sciences (SPSS) version 15.0. Intergroup comparisons were done using ANOVA followed by post-hoc assessments using Tukey HSD test. RESULTS: Mean amplitude and duration with conventional dentures was found to be significantly lower as compared to silicone lined and acrylic lined dentures for all the comparisons. Statistically, no significant difference between silicone lined and acrylic lined dentures was observed for any of the comparisons. CONCLUSION: Within the limitations of this experimental design, it was concluded that relining significantly increases electromyographic activity of the masseter and temporalis muscles. Thus, resulting in an improved biting force, chewing efficiency and masticatory performance. There were no significant differences between silicone and acrylic based denture liners for both electromyographic variables.

Detection of virulence genes in Staphylococcus aureus isolated from paper currency.

BACKGROUND: Infection with Staphylococcus aureus was initially considered a major problem in hospitals, but over the last few decades the incidence of community-acquired infection has also increased. Paper currency has recently been identified as another mode of spread by which community-acquired S. aureus infection may be transmitted, since paper currency is frequently transferred from one person to another. In the present study, S. aureus strains were isolated from paper currency and screened to detect virulence-associated genes. METHODS: Paper currency was collected randomly from operators in mutton shops, vegetable shops, hospitals, medical stores, snacks corners, and restaurants in the two cities of India, Dehradun and Delhi. Samples were screened for pathogenic S. aureus by various biochemical assays. Three isolates were used to study the survival of S. aureus on paper currency. Virulence genes were amplified by PCR. Antibiotic susceptibility was determined against nine antibiotics by the disk diffusion method. RESULTS: Sixty-seven isolates of Staphylococcus aureus were isolated from paper currency from the two Indian cities. The maximum number of isolates was recovered from hospitals, followed by mutton shops, and the minimum from restaurants. The test isolates could survive on paper currency for eight days under in vitro conditions (27 degrees C temperature and 30% relative humidity). A set of four virulence genes viz. cna (16 isolates), icaA (19 isolates), hlg (21 isolates), and sdrE (18 isolates) was amplified using gene-specific primers. Only eight isolates possessed all four virulence genes. Antimicrobial susceptibility tests showed that those isolates having all the tested virulence genes were more resistant. CONCLUSIONS: This study clearly suggests that paper currency can serve as a carrier for the spread of resistant bacterial pathogens.

Molecular typing of clinical Staphylococcus aureus isolates from northern India using coagulase gene PCR-RFLP.

Molecular typing of total 84 Staphylococcus aureus clinical isolates was performed using coagulase gene PCR. Out of 84 S. aureus strains total 33 different types of S. aureus strains were prevalent in this hospital and community. Types 2-7 and 9 were the most prevalent S. aureus strains accounting for more than 53% of total isolates. This technique is relatively inexpensive and is simple to perform and analyze.

Possible role of integrase gene polymerase chain reaction as an epidemiological marker: study of multidrug-resistant Acinetobacter baumannii isolated from nosocomial infections.

Eighty-six strains of Acinetobacter baumannii from India and Nepal were investigated for the presence of integrons in relation to multiple drug resistance by integrase gene polymerase chain reaction (PCR). Integrons were found to be present at a rate of 43.02% (37/86). Integrons were significantly correlated with multidrug resistance to several antibiotics. Class 1 integrons were detected in 81.1% of integron-positive strains, whilst 18.9% were found to be positive for class 2 integrons. The majority of class 2 integrons (71%) were encountered in strains isolated from post-operative wards of both countries. The highest integron carriage in isolates of A. baumannii (63.6%) was observed in 2005. Hence, it is likely that integrons play an important role in antibiotic resistance and possibly indicate epidemic behaviour of A. baumannii. Integrase gene PCR may be used as routine screening and identification for the surveillance of clinical isolates of A. baumannii with epidemic potential.

Valvular flow abnormalities are often identified by a resting focused Doppler examination performed at the time of stress echocardiography.

BACKGROUND: Patients are usually referred for stress echocardiography to assess whether there is inducible myocardial ischemia. At some centers, a focused Doppler examination is also performed. We sought to determine the clinical value of this additional study by examining how often valvular flow abnormalities were identified that might affect clinical care. METHODS: We reviewed 1272 consecutive stress echocardiogram reports from a 1-year period, including 1223 tests that contained focused Doppler data. Important Doppler findings were defined as at least moderate mitral regurgitation, at least mild aortic regurgitation, any aortic or mitral valve stenosis, or any resting left ventricular outflow tract gradient. RESULTS: Overall, focused Doppler identified an important Doppler abnormality in 214 patients (17%). At least moderate mitral regurgitation was identified in 67 patients (5%) and at least mild aortic regurgitation was identified in 163 patients (13%). In addition, aortic stenosis (n = 14; 1%), mitral stenosis (n = 5; 0.4%), and resting outflow tract gradient (n = 2; 0.2%) were noted. A prior echocardiogram had been performed at our institution in 317 patients (26%). For this subset, a new important Doppler finding, a two-step change in regurgitant grade, or a one-step change in stenosis severity was noted in 28 patients (9%). Among patients who had a previous study, the prevalence of new findings was the same (9%) in those who had been studied within the previous year as in those whose previous study had been performed more than 2 years before. CONCLUSION: Focused Doppler documents valvular flow abnormalities in 17% of patients referred for stress echocardiography, thereby enhancing the potential overall value of the test. The frequency of new findings was independent of the time interval from the previous Doppler study. These data should be considered when clinicians choose a stress imaging modality.

Marked abnormalities in heart rate variability are associated with progressive deterioration of renal function in type I diabetic patients with overt nephropathy.

BACKGROUND: Cardiac autonomic neuropathy is a common complication of long-standing, type 1 diabetes and is associated with increased morbidity and mortality. Impaired heart rate variability is a sensitive and reproducible marker of cardiac autonomic neuropathy. We sought to examine the relationship between cardiac autonomic neuropathy as assessed by heart rate variability and overt nephropathy, with emphasis on the progression of renal dysfunction over 1 year. METHOD: Baseline and 12 month clinical and biochemical characteristics, as well as autonomic function tests, were analyzed in 23, type 1 diabetic patients (mean age 37+/-10 years, 65% males), who were prospectively enrolled as a part of a multi-center investigation. In addition, ambulatory, 24-h, 3-channel electrocardiograms were recorded, and heart rate variability indices were assessed in the time and frequency domains over the same period. RESULTS: All heart rate variability indices were markedly decreased in our study population. On univariate analysis, heart rate variability was associated with creatinine clearance, and to a lesser extent, mean 24-h blood pressures and cholesterol. On multivariate analysis, only heart rate variability was a significant and independent predictor of abnormalities in creatinine clearance. Severe reduction in heart rate variability at baseline was also significantly associated with the further deterioration in renal function at 1 year. CONCLUSION: Heart rate variability is significantly reduced in long-standing, type 1 diabetics with proteinuria or overt nephropathy. Marked abnormalities in heart rate variability are significantly associated with and predictive of progressive renal deterioration at 1 year. These findings may have implications for aggressive medical intervention to improve prognosis and survival in this population.