Crushed Returned Concrete Aggregate in New Concrete: Characterization, Performance, Modeling, Specification, and Application

Every year roughly 2% to 10% of the estimated 455 million cubic yards of ready mixed concrete produced in the USA (est. 2006) is returned to the concrete plant. The crushed returned concrete aggregate (CCA) is obtained from crushing the returned concrete that was discharged at the concrete pant and left for a period of time before crushing. It is estimated that about 60% of all returned concrete is managed with this manner by the concrete plant according to the national ready mixed concrete association report. But the reuse of the returned concrete aggregate is very much limited so that most of the returned concrete aggregate has been diverted to the landfill. The main obstacle to limit the use of the returned concrete aggregate is the current type of prescriptive specifications by controlling the concrete composition, which limits the ability to optimize concrete mixtures for performance. The CCA aggregate has useful aggregate properties among which it is free of any contamination. Thus, CCA aggregate is distinguished from other recycled concrete aggregate (RCA) that comes out of existing old structures with high contamination from many years of exposure during the service life. The objective of this research was to develop technical data that will support the use of the CCA aggregates from the returned concrete by the ready mixed concrete industry. Three CCA aggregates at three strength levels were characterized. Thereafter, the virgin coarse/fine aggregates and the three CCA aggregates were used with various amounts to prepare concrete mixtures so as to investigate the effect on the fresh and harden concrete properties. The second objective of this research was to develop the performance models of harden concrete properties. The harden concrete properties of a selected number of mixtures containing CCA aggregates were used for the modeling of compressive strength, drying shrinkage, elastic modulus, and rapid chloride ion penetrability. This analysis was instrumental for a better understanding of how the CCA aggregates affect the harden concrete properties. The fine CCA aggregates were further investigated for their potential use as internal curing agent due to their unique aggregate properties (i.e. low specific gravity and high water absorption capacity). Those two properties are crucial factors for the internal curing. The fine CCA aggregates were used with mortar mixtures to evaluate the strength and autogenous shrinkage behavior along with the lightweight fine aggregate. This new approach can promote the use of CCA aggregate in a specialized application. Another objective of this study was to demonstrate the advantages of using a performance based specification. An example of an experimental case study was used for both conventional and CCA based concrete for comparing performance and prescriptive specifications

The Phenotype of the Food-Allergic Patient

Food allergy\u27s increasing prevalence across the globe has initiated research into risk factors associated with the disease and coexistence with other allergic diseases. Longitudinal birth cohorts have identified food allergy phenotypes of patients based on genetic background, racial diversity, and environmental factors. Identifying food sensitization patterns and coexistence of other allergic diseases allows physicians to provide appropriate care for food allergy and personalized anticipatory guidance for the appearance of other allergic diseases. The authors seek to detail key findings of 4 longitudinal allergy birth cohorts that investigate food allergy and other allergic diseases to further characterize food allergy phenotypes

Behavior and Performance of High Performance Concrete for Pavements

Under TE 30, High Performance Concrete Pavement program, several states are undertaking a variety of innovative research in high performance concrete pavement materials and innovative design/construction features. This project addressed the needs of Maryland State Highway Authority in exploring the use of fiber reinforced and low shrinkage concrete in pavements. Past experience with these materials have indicated i) potential benefits in flexural fatigue resistance and reduction in crack development, and ii) potential reduction in slab warping effects with implications on pavement slab longevity. The objective of this study was to examine the design and lab performance of these materials for Maryland conditions, monitor their lab and field performance, and quantify potential benefits. Extensive fatique modeling was undertaken for developing the fatigue relationships and SN curves for these mixtures. In addition, finite element analysis (FEM) was used to model the behavior of these materials in field conditions and developing the base analytical model to be used in comparing future behavior and performance of the pavement test sections with these mixtures

Persistent hypogammaglobulinemia in CVID secondary to protein losing enteropathy

Case Presentation: Patient is a 40 year old male with PMH of B cell Lymphoma s/p R-CHOP and radiation in remission, Common Variable Immunodeficiency (CVID) diagnosed prior to the hospital admission after IgG levels were found to be/dL (reference range of 700-1600 mg/dL) and recurrent Clostridium Difficile (C. Difficile) admitted to the ICU for left hip abscess and Acinetobacter pneumonia causing septic shock. Patient had a chronic history of septic arthritis of multiple joints, which had required recent antibiotics, and multiple surgeries resulting in persistent wounds causing serosanginous drainage from the surgical sites. Patient underwent incision and drainage the left hip for septic joint while in the ICU and was started on antibiotics. Upon admission, patient’s IgG level was 142 mg/dL and he received 30 g of IVIG infusion. Repeat IgG level one day following IVIG infusion was 565 mg/dL. Fourteen days after the infusion his IgG dropped down to 272 mg/dL. C3 was obtained and was mildly low (most likely due to current infection) and C4 was normal with normal complement activity. Flow cytometry showed normal number of B cells, normal total T cells (with low CD4+ and high CD8+) and normal NK cells. Patient was also found to have persistently low albumin levels, with most recent being 1.9 g/dL (reference range of 3.73-5.65 g/dL). Urinalysis did not demonstrate nephrotic range proteinuria. Due to recent diagnosis and infectious diarrhea due to recurrent C. Diff, it was thought patient was having protein losing enteropathy and loss of protein due to serosanginous drainage from chronic wounds. Due to overwhelming multifocal infections, per family wishes, patient was transitioned to comfort care and passed away peacefully. Discussion: We present a case of a patient with known history of CVID who presented with septic shock and lack of normal IgG levels after recent IVIG infusion due to protein loosing enteropathy and protein loss from chronic wounds. CVID should be suspected in individuals with reduced levels of serum IgG in combination with low levels of IgA and/or IgM, reduced response to immunizations and an absence of any other immunodeficiency state [1]. Our patient was tested for an immunoglobulin deficiency as patient had multiple courses of failure of antibiotics for joint infections. This individual was diagnosed with CVID in 2019 as IgG/dL (L) with concurrent IgA/dL (L) and IgM\u3c 20 mg/dL (L). It was thought the immunoglobulin deficiency was a secondary hypogammaglobulinemia due to Rituximab [2], but there was strong clinical suspicion for true CVID given the severity of his infections. When this patient’s persistent hypogammaglobulinemia was discovered even after IgG infusions, reversible causes were looked into such as nephrotic syndrome. There have been notable cases of protein loosing enteropathies, such as Celiac Disease causing secondary hypogammaglobulinemia or exacerbating a primary disease process, such as CVID [3]. It is likely that patient’s acute drop in IgG 14 days after IgG infusions may have been due to protein loosing enteropathy secondary to recurrent C. difficile diarrhea and protein loss from significant serosanginous drainage from chronic wounds [4,5]. Conclusions: Secondary hypogammaglobulinemia may occur after Rituximab therapy. This case presentation demonstrates the utility in checking IgG levels prior to Rituximab therapy as there may be worsening of immunoglobulin levels post-Rituximab therapy. Acute protein loss can exacerbate CVID and cause overwhelming infections leading to septic shock. Therefore, it is important to determine the etiology of acute protein loss early on in the disease process with underlying CVID as reversible causes that are identified may improve patient outcomes or higher dosing of IVIG may be indicated in such settings where there is a rapid decline of immunoglobulin.https://scholarlycommons.henryford.com/merf2020caserpt/1086/thumbnail.jp

Influence of cytokinins and yeast extract on growth and flavone production in hairy root cultures of Scutellaria baicalensis

Hairy roots produce various bioactive chemical compounds than wild-type roots which offer a promising in vitro approach for synthesizing important nutraceutical compounds. The purpose of this study is to increase the production of flavone compounds in hairy root cultures of Scutellaria baicalensis by the addition of elicitors such as cytokinins and yeast extract. Cytokinins such as kinetin (KIN), 6-benzylaminopurine (BAP), and Thidiazuron (TDZ) were utilized at 0.1, 0.5, and 1.0 mg/L, whereas for yeast extract treatment 50, 100, and 150 mg/L concentrations were added to the ½ SH medium. Effects of elicitors were measured in terms of dry biomass and flavone contents (baicalin, baicalein, and wogonin) using high-performance liquid chromatography (HPLC). The highest dry weight was achieved in the control hairy root than that of all cytokinins-treated hairy root cultures. In all the cytokinin-treated hairy root cultures, as the concentration increased the dry weight of the hairy root decreased. In contrast, in all the yeast extract-treated hairy root cultures as the concentration increases the dry weight of the hairy root increased, whereas the highest dry weight was achieved in 150 mg/L of yeast extract. Moving to the flavone content, baicalin was detected highest content in all the hairy root cultures supplied with cytokinin and yeast extract. The highest total flavone content was achieved in the hairy root culture treated with 1.0 mg/L of TDZ and 50 mg/L of yeast extract. This result might help the commercial agronomic sector by facilitating the in vitro mass production of nutraceuticals using S. baicalensis hairy root cultures

Fabrication of Silver-Impregnated Silica Aerogel Composite for Energy Applications

In this study, Ag-impregnated silica aerogel composites were fabricated via wet impregnation. In this approach, silver salt was reduced with ethylene glycol in the presence of polyvinylpyrrolidone (PVP) at reaction temperature 80°C. PVP was used as a capping agent to protect the Ag nanoparticles (NPs) from agglomeration. Wet impregnation was used to synthesize the Ag/SiO2 composite by combining the reduction of AgNO3 with a silica aerogel slurry. Experimental results showed that the AgNO3 concentration and PVP: AgNO3 ratio had an active influence on the growth of Ag NPs on silica surfaces. The X-ray diffraction (XRD) patterns of the composite material showed no imprints of impurities or parasitic materials except for Ag and SiO2. Scanning electron microscopy (SEM) images revealed that the Ag NPs were well impregnated into the porous silica aerogel structure. It was found that SiO2 aerogel surfaces were homogeneously surrounded by the Ag NPs

Increased risk of asthma at age 10 years for children sensitized to multiple allergens

BACKGROUND: Childhood sensitization patterns have been previously found to be related to variable risk of early life allergic disease in several birth cohorts. OBJECTIVE: To determine whether these risks persist into later childhood. METHODS: In the birth cohort of the Wayne County Health, Environment, Allergy and Asthma Longitudinal Study, previous latent class analysis based on sensitization to 10 allergens found the following 4 early life sensitization patterns at age 2 years: highly sensitized, milk/egg dominated, peanut and inhalant(s), and low to no sensitization. At an age 10 study-specific visit, children were evaluated by an allergist for current asthma and atopic dermatitis through a physical examination and interviews with the child and parent or guardian. Total and specific immunoglobulin E (IgE), spirometry, and methacholine challenge were also completed. RESULTS: Compared with children sensitized to none or 1 allergen, children sensitized to 4 or more food and inhalant allergens at age 2 had the highest risk of current asthma (relative risk [RR], 4.42; 95% confidence interval [CI], 2.58-7.59; P \u3c .001) and bronchial hyperresponsiveness (RR, 1.77; 95% CI, 1.29-2.42; P \u3c .001). In addition, they had the highest levels of total IgE (geometric mean, 800 IU/mL; 95% CI, 416-1536) among the 4 groups. Risk of current atopic dermatitis did not depend on pattern of sensitization but remained increased for children with any sensitization (RR, 2.23; 95% CI, 1.40-3.55; P \u3c .001). No differences in spirometry (forced expiratory volume in 1 second, forced expiratory flow between 25% and 75%, and forced expiratory volume in 1 second/forced vital capacity) were identified. CONCLUSION: The previously reported importance of a specific pattern of sensitization in early life (sensitization to ≥4 inhalant and food allergens) continues to be associated with an increased risk of asthma, bronchial hyperresponsiveness, and high total IgE at age 10 years

Development of a compact ICRF antenna for high-power and long-pulse plasma heating in the KSTAR

For the high-power and long-pulse ion cyclotron range of frequencies (ICRF) heating of the KSTAR plasma, we developed the compact ICRF antenna (CIA). The target injection power of CIA is 2 MW for 300 s. In order to continue injecting the power into plasma even if drastic instantaneous changes occur in the plasma condition, such as ELM events, we adopted the internal conjugate-T method for the load resilience. Between antenna heads and the junction point, impedance transformers were inserted to satisfy the condition of conjugate-T in a limited space keeping the electric field on the transformer low enough. To reduce the risk of water leakage into the vacuum chamber, only the backsides of antenna heads are water-cooled in the in-vessel region

Longitudinal Characterization of Atopic Dermatitis Phenotypes in The Children\u27s Respiratory and Environmental Workgroup (CREW) Birth Cohort Consortium

Rationale: Previously identified longitudinal patterns of atopic dermatitis (AD) may lack generalizability and precision due to small sample size and limited time points. We identify and describe longitudinal AD phenotypes in a large consortium study. Methods: Data from 11 birth cohorts across the United States from the CREW (Children’s Respiratory and Environmental Workgroup) consortium were harmonized to determine physician diagnosis of AD in each year of life from 0-7 years of age (N=7,900). AD phenotypes were identified using Longitudinal Latent Class Analysis, and relationships with demographic variables were determined using multinomial logistic regression with a 3-step procedure to account for uncertainty in class membership. Results: We identified 5 classes of AD expression, selected based on model fit, interpretability, and clinical utility: Persistent AD (15.4%), Early AD with Potential Reoccurrence (2.7%), Late-Onset AD (7.0%), Transient Early AD (3.0%), and Minimal/No AD (72.0%). Males had significantly higher odds of Persistent AD (OR [95% CI]=1.47 [1.22, 1.75]) and Early AD with Potential Reoccurrence (OR [95% CI]=1.89 [1.19, 2.94]). Relative to White children, Black children had higher odds of Persistent AD (OR [95% CI]=2.50 [2.05, 3.05]), Early AD with Potential Reoccurrence (OR [95% CI]=3.07 [1.94, 4.85]), and Transient Early AD (OR [95% CI]=4.12 [2.62, 6.48]). Conclusions: Five AD phenotypes exist in a diverse national sample of children. Black children and males are at increased risk of early and persistent AD. These findings illustrate potential risk factors to target AD prevention