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In Portland cement concrete (PCC) pavements, tie bars are commonly used at longitudinal construction joints (LCJs) to prevent the lanes from separating. Meanwhile, the increase in multiple lanes due to greater traffic volumes has raised concerns about potential longitudinal cracking, this has led to the use of dowel bars instead of tie bars at LCJs. However, there is a paucity of studies focused on the comparison between the behaviors of concrete pavement based on the restrained conditions provided by tie and dowel bars at LCJs. In this study, we investigated the effects of the placement of tie and dowel bars at LCJs on the potential for longitudinal cracking in response to the increase in concrete stress that may occur when the lanes are tied together in PCC pavements. Field testing verified that the variation in concrete strain was more restrained in the case of a tie bar than a dowel bar, whereas it resulted in higher stress in the concrete element in the tie bar section. However, the use of dowel bars caused more movement in the transverse direction at LCJs as compared with tie bars. Thus, our results indicate that using dowel bars reduces the potential for longitudinal cracking, however, it may increase the potential for lane separation.

In continuously reinforced concrete pavement (CRCP) research, it has been assumed that transverse crack spacing plays an important role in determining CRCP behaviour and performance. For the longit...

Fly ash is widely used in the cement industry to improve the performance and durability of concrete. The future availability of fly ash, however, is a concern, as most countries are inclining towards renewable energy sources as opposed to fossil fuels. Additional concerns have been raised regarding the impact of strict environmental regulations on fly ash quality and variability. This paper, therefore, evaluates if nano calcium carbonate (nano CaCO3) can be used as an alternative to fly ash. This paper presents comprehensive testing results (fresh, hardened, and durability) for OPC (Ordinary Portland Cement) and PLC (Portland Limestone Cement) concretes with 1% nano CaCO3 and compares them to those for concretes with fly ash (both Class F and C). Compared to concretes with fly ash, OPC and PLC with nano CaCO3 presented improved testing results in most cases, including later age strength, permeability, and scaling resistance. As nanotechnology in concrete is a relatively new topic, more research on the efficient use of nanotechnology, such as for proper dispersion of nano CaCO3 in the concrete, has potential to offer increased benefits. Further, nano CaCO3 is environmentally and economically viable, as it has the potential to be produced within the cement plant while utilizing waste CO2 and generating economic revenue to the industry. Thus, nano CaCO3 has the potential to serve as an alternative to fly ash in all beneficial aspects—economic, environmental, and technical.

Despite lower environmental impacts, the use of Portland Limestone Cement (PLC) concrete has been limited due to its reduced later age strength and compromised durability properties. This research evaluates the effects of nano calcium carbonate (CaCO3) on the performance of PLC concrete. The study follows a series of experiments on the fresh, hardened, and durability properties of PLC concrete with different replacement rates of nano CaCO3. Incorporation of 1% nano CaCO3 into PLC concrete provided the optimal performance, where the 56 days compressive strength was increased by approximately 7%, and the permeability was reduced by approximately 13% as compared to Ordinary Portland Cement (OPC) concrete. Further, improvements were observed in other durability aspects such as Alkali-Silica Reaction (ASR) and scaling resistance. Additionally, nano CaCO3 has the potential to be produced within the cement plant while utilizing the CO2 emissions from the cement industries. The integration of nanotechnology in PLC concrete thus will help produce a more environment-friendly concrete with enhanced performance. More in-depth study on commercial production of nano CaCO3 thus has the potential to offer a new generation cement—sustainable, economical, and durable cement—leading towards green infrastructure and global environmental sustainability.

Understanding spin textures in magnetic systems is extremely important to the spintronics and it is vital to extrapolate the magnetic Hamiltonian parameters through the experimentally determined spin. It can provide a better complementary link between theories and experimental results. We demonstrate deep learning can quantify the magnetic Hamiltonian from magnetic domain images. To train the deep neural network, we generated domain configurations with Monte Carlo method. The errors from the estimations was analyzed with statistical methods and confirmed the network was successfully trained to relate the Hamiltonian parameters with magnetic structure characteristics. The network was applied to estimate experimentally observed domain images. The results are consistent with the reported results, which verifies the effectiveness of our methods. On the basis of our study, we anticipate that the deep learning techniques make a bridge to connect the experimental and theoretical approaches not only in magnetism but also throughout any scientific research.

In South Korea, the performance of continuously reinforced concrete pavement (CRCP) has been better than that of jointed concrete pavement (JCP). However, most of the Portland cement concrete (PCC)...

The performance of Portland Cement Concrete pavement depends on the support provided by layers under the concrete slab. Considering the importance of slab support on concrete pavement performance, a good quality assurance testing is needed for the construction of layers under the concrete slab. Deflection measurements on stabilized base could provide sound quality assurance testing. A threshold deflection value for construction acceptance was developed from the analysis of the field deflection data as well as theoretical analysis. Based on the information obtained, a protocol for quality assurance testing for base and subgrade construction was developed.

We previously observed a cutaneous type IV immune response in nonhuman primates (NHP) with the mGlu5 negative allosteric modulator (NAM) 7. To determine if this adverse event was chemotype- or mechanism-based, we evaluated a distinct series of mGlu5 NAMs. Increasing the sp3 character of high-throughput screening hit 40 afforded a novel morpholinopyrimidone mGlu5 NAM series. Its prototype, (R)-6-neopentyl-2-(pyridin-2-ylmethoxy)-6,7-dihydropyrimido[2,1-c][1,4]oxazin-4(9H)-one (PF-06462894, 8), possessed favorable properties and a predicted low clinical dose (2 mg twice daily). Compound 8 did not show any evidence of immune activation in a mouse drug allergy model. Additionally, plasma samples from toxicology studies confirmed that 8 did not form any reactive metabolites. However, 8 caused the identical microscopic skin lesions in NHPs found with 7, albeit with lower severity. Holistically, this work supports the hypothesis that this unique toxicity may be mechanism-based although additional work is require...

The fast-track repair of deteriorated concrete pavement requires materials that can be placed, cured, and opened to the traffic in a short period. Type III cement and Calcium Sulfoaluminate (CSA) cement are the most commonly used fast-setting hydraulic cement (FSHC). In this study, the properties of Type III and CSA cement concrete, including compressive strength, coefficient of thermal expansion (CTE) and shrinkage were evaluated. The test results indicate that compressive strength of FSHC concrete increased rapidly at the early age. CSA cement concrete had higher early-age and long term strength. The shrinkage of CSA cement concrete was lower than that of Type III cement concrete. Both CSA and Type III cement concrete had similar CTE values. Based on the laboratory results, the CSA cement was selected as the partial-depth rapid repair material for a distressed continuously reinforced concrete pavement. The data collected during and after the repair show that the CSA cement concrete had good short-term and long-term performances and, therefore, was suitable for the rapid repair of concrete pavement.

Frailty is now a well-recognized and common syndrome among older persons. Frailty is a syndrome which increases the risk of an older person to develop disability or to die when exposed either to physical or psychosocial stressors. Although frailty, disability and multimorbidity often coexist and interact, they are distinct and separate concepts. Growing evidence suggests that each of these interrelated conditions is preventable and their associated complications manageable. However, early identification is imperative as once disability and multimorbidity occur, frailty in less likely to be prevented or reversed. As such it should be distinguished from persons with disability in their activities of daily living. The conditions leading to the frailty syndrome should have some degree of reversibility, thus distinguishing it from multimorbidity. Recently, the International Conference of Frailty and Sarcopenia Research (ICFSR) formulated evidence-based guidelines for the identification and management of physical frailty. Physical frailty was originally defined and validated by Fried et al. This definition included measurements of low activity level, slowness of walking, muscle weakness, exhaustion and weight loss. This approach differs from that of Rockwood and Mitnitski which used the number of “deficits” (signs, symptoms, clinical conditions) to determine a frailty index. Primary care represents the entry point into the health care system for many older adults who may be pre-frail and frail. A shortage of geriatricians and the higher frequency of frailty in community settings call for primary care clinicians (general practitioners, generalists, family physicians) to increasingly assess and manage older adults at risk for frailty or who are already frail.The purpose of this paper is to suggest practical frailty screening and management strategies in primary care settings. We will also discuss the characteristics of these instruments and their applicability to primary care. For the sake of consistency hereafter, we will refer to clinicians delivering primary care as primary care providers.

The Argonaute (AGO) family of proteins plays an essential role in the process of microRNA (miRNA)-mediated gene silencing. More specifically, they are the only known proteins to associate directly with miRNAs within the RNA-induced silencing complex (RISC). Given the importance of miRNA regulation of the transcriptome and its vast implications for human disease, it is essential to understand the molecular underpinnings of miRNA-AGO interactions. Although there are methods available to investigate mature miRNA decay and loading onto AGO2, no feasible method exists to detail the opposite process: release of miRNA from associated AGO proteins. In this chapter, we describe in detail a methodology derived from biochemical approaches, which can be used to quantify the release of any given miRNA from AGOs.

The Argonaute (AGO) family of proteins plays an essential role in the process of microRNA (miRNA)-mediated gene silencing. More specifically, they are the only known proteins to associate directly with miRNAs within the RNA-induced silencing complex (RISC). Given the importance of miRNA regulation of the transcriptome and its vast implications for human disease, it is essential to understand the molecular underpinnings of miRNA-AGO interactions. Although there are methods available to investigate mature miRNA decay and loading onto AGO2, no feasible method exists to detail the opposite process: release of miRNA from associated AGO proteins. In this chapter, we describe in detail a methodology derived from biochemical approaches, which can be used to quantify the release of any given miRNA from AGOs.

Lane separations at longitudinal joints not only allow water to infiltrate into layers under the concrete slabs and deteriorate slab support, but degrade load transfer efficiency (LTE) along longitudinal joints, resulting in an increase in load-related stresses in concrete slabs and poor performance of pavement. Slot stitching provides one of the more efficient methods to restore pavement structural capacity due to lane separations. In 2010, three slot stitching design configurations were implemented on US-75 in Sherman, Texas, which experienced lane separations as well as faulting along the longitudinal construction joint. After the dowel bars were installed, the ultra rapid repair method with the use of high early strength, low shrinkage, and low coefficient of thermal expansion (CoTE) backfill materials was utilized to minimize the traffic interruption and to restore the elevation. For measuring the effectiveness of the repair method, LTE at longitudinal joints was evaluated using Falling Weight Deflectometer (FWD). Testing results in this paper demonstrate the effect of slot stitching design, or more specifically the number of slot stitching in a slab and/or bar size, on improving LTE by providing before-and-after LTE measurements and detailed material information. In particular, the design configuration with 5 #8 bars (25.4-mm diameter) was the most cost-effective and efficient, with about 28% improvement in LTE after more than 4 years of service. Moreover, three design configurations with the use of low-shrinkage, low-CoTE backfill materials were demonstrated to improve LTE substantially, with an average increase from 45% to 74%.

Continuously reinforced concrete pavement (CRCP) behavior due to temperature and moisture variations was analyzed using a mesoscale model consisting of coarse aggregate, mortar, and an interface transition zone (ITZ). The effects of the modulus of elasticity and thermal coefficient of the coarse aggregate and the strength at ITZ were evaluated. The results indicated that the coarse aggregate modulus and the drying shrinkage of the concrete had the most significant effect on the development of nonstructural distresses. Using a coarse aggregate with a lower modulus and reducing the drying shrinkage of concrete are thus expected to improve CRCP performance.

Primary care physicians are often the first point of contact for individuals with ASD and their families, and they continue to play an important role throughout treatment. Physicians often play the role of mediator and leader in many multidisciplinary and other models of treatment teams. This chapter addresses the role and expertise of physicians within the context of interdisciplinary teams. In addition, it discusses the importance and differences between several types of primary care physicians, including developmental-behavioral pediatricians and the unique areas of expertise that they bring to the team.

To determine the percentage of children with autism spectrum disorder (ASD), attention-deficit/hyperactivity disorder (ADHD), and combined ASD + ADHD who had sleep problems documented by developmental-behavioral pediatricians at diagnostic and follow-up visits at 12 US academic medical centers comprising the Developmental-Behavioral Pediatrics Research Network (DBPNet) and to identify the predictors of sleep problem documentation.Developmental-behavioral pediatricians completed encounter forms that covered sociodemographic, medical, clinician, and visit factors. There was 1 dependent variable, sleep problem documentation, for which 4 definitions were developed (Model 1 = Sleep Disorder coded; Model 2 = Sleep Disorder or polysomnogram coded; Model 3 = Sleep Disorder, polysomnogram, or sleep medication coded; and Model 4 = Sleep Disorder, polysomnogram, sleep medication, or clonidine coded).Sleep problem documentation was 14.1% for Model 1, 15.2% for Model 2, 17.3% for Model 3, and 19.7% for Model 4. All values were lower (p0.001) than the reported prevalence of sleep problems in these conditions. For Model 4, predictors of sleep problem documentation were age group, ethnicity, medical insurance type, and DBPNet site.Developmental-behavioral pediatricians in DBPNet under-reported sleep problems in children with ASD and ADHD. Variation among sites was substantial. Care plans for children with ASD and ADHD should specify which treating clinician(s) monitors sleep issues.