Generally, the concrete with higher strength appears to produce brittle failure more easily. However, the use of mineral admixture can help in enhancing the ductility, energy dissipation, and seismic energy in the designed concrete. This paper presents energy absorption capacity, stiffness degradation, and ductility of the copper slag (CS) admixed reinforced concrete with fly ash (FA) beams subjected to forward cyclic load. The forward cyclic load was applied with the help of servo-hydraulic universal testing machines with 250 kN capacity. Twenty-four beams with a size of 100 mm × 150 mm × 1700 mm made with CS replaced for natural sand from 0% to 100% at an increment of 20%, and FA was replaced for cement from 0% to 30% with an increment of 10% were cast. Beams are designed for the grade of M30 concrete. Based on the preliminary investigation results, compressive strength of the concrete greatly increased when adding these two materials in the concrete. Normally, Grade of concrete can change the behaviour of the beam from a brittle manner to be more ductile manner. So, in this work, flexural behaviour of RC beams are studied with varying compressive strength of concrete. Experimental results showed that the RC beam made with 20% FA and 80% CS (FA20CS80) possesses higher ultimate load-carrying capacity than the control concrete beam. It withstands up to 18 cycles of loading with an ultimate deflection of 60 mm. The CS and FA admixed reinforced concrete composite beams have excellent ultimate load carrying capacity, stiffness, energy absorption capacity, and ductility indices compared to the control concrete beam. Offshore structures are built to withstand both static and cyclic loads caused by ocean waves. Cyclic loading refers to the continuous and repeated load application on material or structural components that causes material degradation and, eventually, fatigue. Materials deteriorate due to fatigue when subjected to cyclic loading. Polymer cement concrete with 5% and 15% cement replacement by ground tire rubber and epoxy exhibited good structural behaviour . The extThe CS in reinforced cement concrete elements increases the compressive, splitting tensile, flexural strength, and energy absorption characteristics significantly . The conSimilarly, the production of energy is reliant on coal-fired thermal power plants. According to research published by the national thermal power corporation in Noida Uttar Pradesh, India, ash generation is predicted to rise every year due to the current boom in the power sector . A consiReportedly, it was found that the strength of the mix with 40% FA substitution is always lower than that of the control mix ,26,27,28Durability indicators such as water absorption and permeability are commonly decreased continuously. Reportedly, the use of 100% CS showed the best alternative material for sand to attain higher hardened strength properties . It is a2 in hydrated cement paste to form complex compounds that reduce permeability, prevent corrosion, and improve durability while also improving the economy of the mix [The use of CS as sand replacement yielded a comparable increase in compressive and flexural strength, and the optimum percentage of CS for mechanical strength and chemical resistance was 60% . The chl the mix . Much re the mix . Based oOrdinary Portland cement (OPC) 43 grade cement was used in the experimental investigation, which was confirmed with Indian Standard IS8112 Part1: 2013 , and phyThe gradation of an aggregate affects both the fresh and hardened concrete properties. The well-graded aggregate sample contained minimum voids, and, also, minimum paste required to fill the void in the aggregate. The gradation curve of fine aggregate was compared with the curves obtained from fine aggregate replaced with CS from 0% to 100% with 20% increment. From the particle size distribution, the fineness modulus for fine aggregates are 2.79, 2.8, 2.83, 3.10, 3.20, and 3.52, respectively, for 0%, 20%, 40%, 60%, 80%, and 100% CS replacement for fine aggregate. Introduction of CS shifts the gradation curve towards right because the fineness modulus values are increased. Microstructure study was conducted by EDAX  for FA and CS. EDAX shows that the major components are Ca, Si, Fe, Mg, and Al and the minor components are Na, Ti, K, and Pd. EDAX images of CS and FA are shown in the Mix design is prepared for M30 grade of concrete according to IS: 10262-2009. Twenty-four mixes are prepared in the laboratory where cement is partially replaced by FA from 0, 10, 20, and 30%, (by mass), respectively, and fine aggregate is replaced by CS from 0, 20, 40, 60, 80, and 100%. Compressive strength test has been conducted on 432 cubes of size 150 mm × 150 mm × 150 mm at 3, 7, 14, 28, 56, and 90 days curing period using a compression testing machine  with 2000 kN capacity see . QualityEach beam had a cross section of 100 mm × 150 mm and 1700 mm long. High yield strength deformed (HYSD) Fe415 steel bars are used as reinforcements The main reinforcements were two 10 mm diameter deformed bars for both tension and hanger bar. The 6 mm diameter bars are used as stirrups at 60 mm spacing at shear span and 120 mm spacing (double spacing) in pure bending zone. All the specimens were designed as under-reinforced beams as per the Indian Standard IS456-2000 . All theThe beam spanning 1500 mm was subjected to four-point bending flexural testing. The load was applied with help of servo-hydraulic universal testing machines fitted with a 250 kN capacity load cell and 300 kN actuator. The servo-hydraulic UTM was purchased from M/s AIMIL Ltd., New Delhi, India. Both monotonic and cyclic loadings are applied to the control reinforced concrete beam. Flexural behaviours of the remaining beams are tested by cyclic load only and they are compared with the flexural behaviour of the control reinforced concrete beam. Spreader beam was placed over a concrete beam at the distance of l/3 points from each support as shown in Forward cyclic load was applied on the specimen by using servo-hydraulic UTM 250 kN capacity with MTL32-2020 software . The beam was gradually loaded by increasing the load level in each cycle. The load was applied from 0 to ultimate level at an increment of 2 kN . The deflection of the beam was measured for every load increment. The beam was loaded up to the first increment, then unloaded until the force equal to zero and reloaded to the next increment of load and vice versa. This procedure was followed up to failure of the specimen and this pattern of loading will be continued for all twenty-four beams up to failure. The first crack was marked on the specimen and simultaneously, the no of cycles was noted down for the corresponding first crack. Yield load, ultimate load carrying capacity, energy absorption, ductility index, and stiffness of concrete beams and modes of failure are considered in this study.In earthquake resistant design, a prime consideration is about the ability of the structure to deform in a ductile manner, when subjected to several cycles of lateral loading well into the inelastic range. Monotonic load and forward cyclic load are applied to the control concrete RC beam. Remaining beams are loaded by forwarded cyclic load and compared with control concrete beam subjected to cyclic loading condition.Load history for monotonic and forwarded cyclic loads is represented in The load–displacement curve at mid span section is an important factor for the evaluation of mechanical behaviour of simply supported reinforced concrete beam. So that the mid-span deflection of the reinforced concrete composite (RCC) beam with cyclic loading was compared with control concrete beam and represented in From the load–deflection curve a, it canFrom the load–deflection curve b, it canThe specimens with FA 20% to 30% with CS 80% have achieved 35.4 kN and 34.98 kN and their corresponding deflections are 60 mm and 55.24 mm, respectively. This shows that ductile behaviour was high for RCC beams incorporating CS and FA admixed beams. It was observed that the maximum failure load has been obtained for (FA20CS80) beam, and it was 35.40 kN, whereas for control concrete beam, it was 31 kN only.From these figures, it can be seen that, in the initial stage of loading the specimen was in elastic range. Hence the area under the load–displacement curve was very small. With the increase in load, the specimen transferred from elastic range to elastic-plastic range then automatically formation of crack will occur. The increase in damage also observed with the decrease in stiffness of the specimen. At last, the area under the load–displacement curve increased successively. This is also an indication for dissipation of energy during the loading and unloading process. CS replacement does not affect the load carrying capacity .Stiffness is the main variable controlling safety against instability. Stiffness is defined as the load required causing unit deflection of the RC beam. Generally, the increase in displacement degrades the Stiffness. The stiffness of the structural members gradually decreases with increasing cycles of loading. The beam FA30CS20 see d has 34.One of the most important parameter of the structure under seismic loading is energy dissipation capacity. It is defined as the ability of the structure to dissipate the energy. Generally, the energy absorption capacity of the beam members can be approximated as the area is enclosed by the hysteresis loop (load–deflection curve). When the beam is subjected to cyclic loading such as those experienced during heavy wind or earthquake, some energy is absorbed in each cycle see . It is eMoreover. the beams FA0CS0-100 see a has shoDuctility is the ability of the structure which is used to compensate the brittle failure. Ductility of a structure or its members is also defined as the capacity to undergo large inelastic deformation , without significant loss of strength or stiffness. If a structure is ductile, it can be expected to adapt to unexpected overloads, load reversals, impact, and structural moments, due to the foundation settlement and volume of changes. Secondly, if the structure is ductile, its occupants will have sufficient warning of the impending failure, thus reducing the probability of loss of life in the event of a collapse. In this work, ductility factor see  is definDuctility index is used to determine the ductile nature of the beam. It can be seen that FA20CS20 c is moreFailure pattern of RC beams were depicted in the This type of admixed beams may be recommended for the structures located in seismic prone areas. At ultimate load condition, the beams fail with the crushing of concrete at the top compression region. However, none of the beams has a shear failure. It indicates that the shear reinforcement provided was sufficient to carry the shear.Preliminary investigation results are supported by the work of other researchers who studied the influence of CS as fine aggregate on the strength of mortars, concrete specimens, durability studies, and flexural behaviour of RC beams. Compressive strength of concrete significantly increased up to 90 days, and capillary porosity decreased due to densification of structures when concrete with 15% CS replaced for cement and 1.5% hydrated lime is used to activate the hydration . OptimumIn reinforced concrete design, only the strength of the concrete with compression was taken into consideration. Based on the previous research, concrete with CS replaced for fine aggregate gives higher strength than the control concrete. In this work, detailed study was carried out on the RC beams made with different mix proportions subjected to forward cyclic loading. This paper presents energy absorption capacity, stiffness degradation, and ductility of the copper slag (CS) admixed reinforced concrete beams with fly ash (FA) subjected to forward cyclic load. The forward cyclic load was applied with help of servo-hydraulic universal testing machines with 250 kN capacity. Based on the experimental investigation the following conclusions were made. -During the monotonic loading condition, the control concrete RC beam withstands the ultimate load of 35kN. The first crack was observed at the load of 15.17 kN. It was found that when the specimen loaded under cyclic loading condition, the control concrete beam withstands the ultimate load of 31.78 kN, and the first crack was observed at the load point of 9.94 kN.-It was found that the specimens with 20% FA and 80% CS (FA20CS80) possesses higher ultimate load carrying capacity compared to the control concrete beam. It withstands up to 18 cycles of loading with ultimate deflection which was 60 mm.-The stiffness of the structural members gradually decreases with increasing cycles of loading. RCC beam FA30CS20 has 34.78% more stiffness compared to the control concrete beam, and, also, the percentage reduction is less.-The beam FA20CS20 has 77.85% higher ductility factor than the control beam, whereas the beam FA0CS60 has 37.22% lower ductility factor than the control beam. The beam FA30CS40 has 90.66% lower energy absorption capacity than the control beam, whereas the beam FA30CS80 has 69.2% higher energy absorption capacity than the control beam.-The CS and FA admixed RCC beams have shown excellent ultimate load carrying capacity, stiffness, energy absorption capacity, and ductility factor compared to the control concrete beam. Because, the density and the stiffness of concrete are increased, due to irregular surfaces of CS filled with hydration products.-At ultimate load condition, the beams fail with the crushing of concrete at the top compression region. However, none of the beams has a shear failure. It indicates that the shear reinforcement provided is sufficient to carry the shear.-It is also proposed that when determining the CS replacement amount, the required concrete compressive strength be taken into account.Based on the major findings of this study, it is recommended to perform a wide-range of theoretical analysis and numerical modelling for this designed system of RC beams.


The proper disposal of used rubber tires has emerged as a primary concern for the environment all over the globe. Millions of tires are thrown away, buried and discarded every year, posing a major environmental concern owing to their slow decomposition. As a result, it is advantageous to use recycled waste rubber aggregates as an additional building resource. Recycling crushed rubber would lead to a long-term solution to the problem of decreasing natural aggregate resources while conserving the environment. This study examines the impact strength variability and reliability of preplaced aggregate concrete containing crumped rubber and fibres. Ten different mixtures were prepared by replacing natural aggregate with crumped rubber . The crumped rubber was pretreated by the water with sodium hydroxide dilution for 30 min before usage. Hooked-end steel fibres were used at a dosage of 1.5%. The compressive strength, impact strength, impact ductility index and failure pattern were examined and discussed. In addition, a statistical method called Weibull distribution is used to analyze the scattered experimental results. The results showed that when the crumb rubber content was raised, the retained first cracking and failure impact numbers increased. As a result of substituting crumb rubber for 20% of the coarse aggregate in plain and fibrous mixes, the percentage development in first crack and failure was between 33% and 76% and 75% to 129%, respectively. Concrete is producing considerable use of recyclable and solid waste resources to address environmental challenges and reduce energy consumption . FurtherBecause of such limitations, investigators now have the opportunity to examine alternate applications for waste tire rubbers and develop methods that are more environmentally friendly. In the past, investigators used discarded rubber partially as a coarse aggregate in concrete. When natural coarse aggregate was replaced with rubber, concrete’s compressive and splitting tensile strengths were reduced by roughly 85 and 50% for 100% rubber substitution, respectively . SeveralSeveral investigators have reported that rubber-based concrete lacks mechanical properties ,20,22,23In many experiments, fibers and crumpled rubber were shown to have a good influence on concrete’s impact characteristics. As a result, there is no evidence of the creation of preplaced aggregate concrete (PAC) using the crumpled rubber limited from the technical literature. Due to its unique production technique, PAC is a new composite that varies from standard fibrous concrete. Coarse aggregates and fibers were combined in PAC and adequately placed in the framework before grout was injected into the interparticle void region . Small q2.According to IS: 12269–1987  requiremThe fine aggregate was obtained from a natural river that was located nearby. It had a specific gravity of 2.65 and a fineness modulus of 2.41, which is in accordance with the requirements of IS: 383–2016  was vali3, while the percentage of water absorption value was 0.56. To improve the flowability of the grout and satisfy the criteria for the efflux time, a superplasticizer called Tec Mix 640 that is available for commercial purchase was used. The pH value of the superplasticizer that was utilized was between 7 and 8. For the non-fibrous and fibrous specimens, the doses of chosen superplasticizers were 0.3 and 0.6% (by cement weight), respectively.The size of the granite gravel that was utilized for the coarse aggregate was 12.5 mm. The coarse aggregates had a specific gravity of 2.69 and a bulk density of 1700 kg/m3. Rubber was sourced from a mechanical shredding plant in Madurai, Tamil Nadu, India. All mixtures were made with crumpled rubber free of steel belts and ranged from 12 to 18 mm.The recycled rubber recovered from shredded tires had a density of 700 kg/mCarbon hooked end steel fibre of the corrugated type, which has 1400 MPa tensile strength, a 60-mm length and 0.75-mm diameter, was employed in the concrete at a 1.5% dose. It is necessary to pre-treat rubber in order to increase its adhesion to the cement. Rubber tires are frequently treated with NaOH solution before use to remove the coating of zinc stearate that has been developed on their surface, rendering them rough and porous . Rubber w/c) and sand-to-cement (s/c). A large number of trial grout mixes were created in order to optimize the water-to-cement and sand-to-cement ratios as well as the amount of superplasticizer that was required to meet the required efflux time (35–40 ±2s)  for each test data point with the corresponding impact numbers ln(T1 or T2). Assuming that data points are linearly correlated, it is reasonable to conclude that impact strength information follows the two-parameter distribution of Weibull. The shape parameter is obtained directly from the slope of the line derived from the linear equation, whereas the scale parameter is derived from Equation (10) as follows.Weibull functions define the impact strength equations given above, and can be written by using the linear function of Equation (8). It is possible to determine whether impact test data was distributed using the Weibull two-parameter distribution. Based on the impact results tests, a straightforward linear regression analysis was performed. It was demonstrated that test data confirmed the distribution of the two-parameter Weibull when an excellent linear correlation between Weibull parameters were evaluated and used to assess impact strength that correspond to the necessary reliability level, and are expressed in Equation (11)  as a fun2) of the fitting results for all tested data was between 0.9 and 1.0 in all cases. This clearly shows that Y and X are linearly dependent on one another. In other words, impact strength follows the two-parameter distribution of Weibull’s law of large numbers.The results of the linear regression analysis of the specimen are shown in 2 values for T1 and T2 for this mixture was above 0.9. Impact strength (T1 and T2) for the other mixtures of concrete specimens can be derived from 2 values for all specimens was above 0.9, which showed an effective fit linear regression. Reliability analysis with the aid of Weibull distribution was used to analyze differences in the experimental testing dataset appropriately. This eliminated the money and effort of evaluating the impact strength of the rubber-based concrete specimens through the drop weight test. A designer can select the impact strength from The calculated Weibull parameters were used to assess the reliability of impact numbers T1 and T2. This study examines the combined effect of steel fibre and rubber aggregate in concrete under drop weight impact. The four different percentages of rubber content  with constant fibre dosage were used to produce specimens and tested. Based on the findings obtained from the research, the following conclusions may be inferred.The compressive strength of the rubber-based fibrous concrete decreased from 46.34 to 39.75 MPa as the rubber content increased from 5% to 20%. Compared with the R0-F mixture, the compressive strength of rubber-based concrete was decreased by 3.9, 8.2, 13.2 and 17.6% when the corresponding rubber content was 5, 10, 15 and 20%, respectively.Owing to their high plastic energy capacity and superior ductility, crumb rubber particles work as randomly distributed shock absorbers in the mixture, which results in a tougher and more ductile mixture with higher impact energy absorption capacity. As a result, the retained cracking T1 and failure T2 impact numbers were increased as the content of crumb rubber was increased. The percentage developments in T1 and T2 due to the substitution of 20% of the mixture’s coarse aggregate by crumb rubber were in the ranges of approximately 33% to 76% and 75% to 129%, respectively, for plain and fibrous mixtures.Steel fibre was found to be a better impact resistance enhancer compared to crumb rubber. The percentage developments due to the sole effect of SF were in the ranges of approximately 113% to 183% for T1 and 326% to 457% for T2, for all crumb rubber ratios. The better effect of SF is mainly due to the crack bridging activity that continues even after crack propagation and widening, which is attributed to the fiber’s high tensile strength and the superior bond with the surrounding matrix.The dual action of crumb rubber and SF was found to be very effective in achieving the best impact resistance enhancement results. The percentage improvements of the fibrous rubberized mixtures compared to the reference plain mixture that includes no rubber ranged from approximately 206% to 275% for T1 and 573% to 876% for T2. This gain represents the summation of the positive actions of both materials as shock absorbers and crack bridging elements.The impact ductility was increased by the incorporation of crumb rubber and was better improved by the addition of 1.5% of hooked-end SF, while the dual action of the two materials resulted in the highest ductility improvement percentages. The use of 20% of crumb rubber increased the ductility index by approximately 31% to 33%; the used 1.5% of SF increased the ductility index by approximately 98% to 106%, while a percentage improvement range of approximately 118% to 158% was achieved by their combined effect. Additionally, the poor interfacial bonding between the rubber aggregate and cement matrix is due to a larger porosity in rubber aggregates and the increased specific surface area of the concrete. This effect can be minimized by the bridging action of steel fibres that resulted in the higher ductility index of concrete.Impact numbers for T1 and T2 in terms of the required level of reliability were evaluated from the Weibull distribution, which can be accepted as a useful statistical analysis approach to determine the impact resistance of specimens without additional expensive and time-consuming tests. The Weibull distribution is an excellent choice to elucidate scattered test results.


Immunoglobulin (Ig) G4-positive cells are rarely observed in the lungs of patients with idiopathic interstitial pneumonias (IIPs). IgG1 may be more pathogenic than IgG4, with IgG4 having both pathogenic and protective roles in IgG4-related disease (IgG4-RD). However, the role of both IgG1 and IgG4 in IIPs remains unclear. We hypothesized that patients with IgG4-positive interstitial pneumonia manifest different clinical characteristics than patients with IgG4-RD. Herein, we identified the correlation of the degree of infiltration of IgG1- and IgG4-positive cells with IIP prognosis, using a Japanese nationwide cloud-based database. We included eighty-eight patients diagnosed with IIPs after multidisciplinary discussion, from April 2009 to March 2014. IgG4-positive cell infiltration was identified in 12/88 patients with IIPs and 8/41 patients with idiopathic pulmonary fibrosis (IPF). Additionally, 31/88 patients with IIPs and 19/41 patients with IPF were diagnosed as having IgG1-positive cell infiltration. IgG4-positive IIPs tended to have a better prognosis. Conversely, overall survival in cases with IgG1-positive IPF was significantly worse. IIPs were prevalent with IgG1- or IgG4-positive cell infiltration. IgG1-positive cell infiltration in IPF significantly correlated with a worse prognosis. Overall, evaluating the degree of IgG1-positive cell infiltration may be prognostically useful in cases of IPF. Up to 35% of patients with IgG4-RD present with intrathoracic lesions, including those involving the mediastinal lymph nodes, bronchial walls, and peribronchovascular bundles4. All lesions in the thorax have been comprehensively classified as IgG4-related respiratory disease (IgG4-RRD)5. However, the diagnosis of IgG-RRD is sometimes difficult and requires multidisciplinary discussion (MDD)6.Immunoglobulin (Ig) G4-related disease (IgG4-RD) is a systemic disease characterised by an elevated serum IgG4 concentration and IgG4-positive plasma cell infiltration into multiple organs14 have been reported. Recently, we reported 16 cases with clinical characteristics of interstitial pneumonia, abundant IgG4-positive cells in the lungs and elevated serum IgG4 levels without extra-thoracic lesions15. In most cases, marked numbers of lymphoplasmacytic cells in the fibrous parenchyma were observed. In contrast, none of the 16 patients had either obliterative vasculitis or storiform fibrosis, which are characteristic of IgG4-RD. In addition, progressive fibrosis was observed despite glucocorticoid treatment. We speculate that these cases have IgG4-positive interstitial pneumonias, and should be given an alternative treatment compared to those with IgG4-RRD.Additionally, various types of idiopathic interstitial pneumonia (IIP) with IgG4-positive plasma cell infiltration in the lungsWe thought that it was necessary to examine the frequency of IIPs with IgG4-positive cell infiltration in lung tissues and to investigate the clinical significance of IgG4-positive cell infiltration.16. Recently, it has been suggested that IgG1 has pathogenic roles and IgG4 has both pathogenic and protective roles in IgG4-related pancreatitis (autoimmune pancreatitis)17. We speculated that IIPs with abundant IgG1-positive cells may have a poor prognosis regardless of the degree of IgG4-positive cells. However, the roles of IgG1 and IgG4 in patients with IIPs remain unclear. Therefore, it was necessary to examine the clinical characteristics of patients with IIPs with or without IgG1 as well as IgG4-positive cell infiltration.Furthermore, whether IgG4 antibodies are active in the pathogenesis of this disease also remains to be elucidated. IgG4 is considered to be a weak-inflammatory or more specifically anti-inflammatory IgIn this study, we retrospectively analysed the presence of IgG-, IgG1-, and IgG4-positive cells by immunostaining surgical lung biopsy (SLB) specimens obtained from patients with IIPs. The patients’ diagnoses were confirmed by MDD. The current study is the largest survey of IgG4-positive cells in SLB specimens for IIPs and the first one evaluating IgG1-positive cell infiltration in SLB specimens for IIPs.The MDD diagnoses of the 88 patients are shown in Table The median follow-up period in cases of IIPs was 3.93 years (range 0.05–12.59). During the follow-up period, acute exacerbation and lung cancer developed in 22 patients (25.0%) and three patients (3.4%), respectively. None of the patients developed extra-thoracic IgG4-RD. Thirteen patients died of chronic respiratory failure, six patients died from an acute exacerbation, and four patients died from an infection in the follow-up period. In IIPs, the median numbers of positive cells per high-power field (HPF) in the immunohistochemistry for IgG, IgG1, and IgG4 were 22, 14, and 2, respectively. The IgG1 + /IgG + ratio and IgG4 + /IgG + ratio were 67.3, and 6.5, respectively.In the IPF group, the median numbers of positive cells per HPF in the immunohistochemistry analysis for IgG, IgG1, and IgG4 were 28, 30, and 1, respectively. The IgG1 + /IgG + ratio and IgG4 + /IgG + ratio were 73.9 and 5.8, respectively.p < 0.01), while there was a weak positive correlation between IgG1-positive cells and IgG4-positive cells   were diagnosed as having IgG4-positive IIPs; among patients with IPF, 8 of 41 patients (19.5%) were diagnosed as having IgG4-positive IPF, according to this definition. Similarly, one of nine idiopathic non-specific interstitial pneumonia (iNSIP) patients (11.1%), and one of six desquamative interstitial pneumonia (DIP) patients (16.7%), were diagnosed as having IgG4-positive IIPs , IgG4-positive IIP was diagnosed with reference to the proposed IgG4-RRD diagnostic criteria0/HPF, IgIn this study, the cells with a score greater than 3 (> 30/HPF) with reference to the median number of IgG1-positive cells in IPF were defined as IgG1-positive cells. Among the 88 patients with IIP, 31 (35.2%) were diagnosed as having IgG1-positive IIPs; among the 41 patients with IPF, 19 (46.3%) were diagnosed as having IgG1-positive IPF. Similarly, three of nine (33.3%) patients with iNSIP, and two of six (33.3%) patients with DIP were diagnosed as having IgG1-positive IIPs .The characteristics of the groups are summarised in Table The Kaplan–Meier curves of overall survival (OS) for patients with or without IgG4-positive cells are shown in Fig. We compared the patients with IIPs and IPF with or without IgG1-positive cell infiltration . The characteristics of the groups are summarised in Table The Kaplan–Meier curves of OS for the IgG1-positive or IgG1-negative group are shown in Fig. p = 0.030) and the incidence of acute exacerbation  were associated with a high risk of death. The multivariate analysis showed that IgG1-positive cell > 30/HPF  and the incidence of acute exacerbation  were independently associated with a high risk of death  and 10% of NSIP15. Herein, 6 of 88 patients with IIP and 3 of 41 patients with IPF fulfilled both conditions of > 40% IgG4 + /IgG + ratio and > 10 IgG4-positive cells per HPF. Notably, none of the patients developed IgG4-RD. It was plausible that IgG4-positive cells were expressed in IIPs independent of IgG4-RD, although only a few patients were evaluated for serum IgG4 concentration.Recently, we defined IgG4-positive interstitial pneumonia as a condition with elevated serum IgG4 concentrations (≥ 135 mg/dL) and infiltration of abundant IgG4-positive plasma cells 20. Xue et al. reported that patients with IPF who had enriched B lymphocyte stimulating factor (BLyS) had a worse survival rate than those with lower levels of BLyS21. Although further research is warranted, IgG1-positive cells in SLB specimens may be a prognostic indicator of patients with IPF. Therefore, the use of antifibrotic agents in the early stage of IPF or new therapeutic strategies may be required in cases of IPF that also have abundant IgG1-positive cells in the lung. However, further studies are needed to clarify this problem.On the contrary, IgG1-positive IPF showed a significantly worse survival rate than did IgG1-negative IPF. In immunohistochemistry, IgG1-positive cells are IgG1-positive plasma cells or lymphoid cells containing IgG1. It might be considered that IgG1-positive IPF means IPF involving B cells. Although a precise understanding of the relationship between B cells and IPF remains elusive, there are some existing reports on B cells and IPFIn this study, the evaluation of IgG1-positive cells was performed at the sites with abundant IgG4-positive cells. There was no consistent trend in the degree of infiltration by IgG1 and IgG4-positive cells. The present study did not prove that IgG1 is responsive to IgG4. In the future, it will be necessary to evaluate whether IgG4 is found around fibrotic foci or fibrosis to assess whether IgG4 plays a protective role. On the other hand, it has been suggested that abundant IgG1-positive cells, regardless of IgG4-positive cells, is considered a poor prognostic factor of IPF.22 and has a low affinity for Fc receptors23. IgG4 is considered weak-inflammatory; rather it has the potential to cause a reduction in the immune activation of Igs16. Shiokawa et al. revealed that subcutaneous injections of IgG from patients with autoimmune pancreatitis (pancreatic lesion of IgG4-RD) led to organ injuries in a mouse model17. Organ injury was also induced by injecting IgG1 and IgG4 from these patients into mice; IgG1 injection caused more destructive changes compared to IgG4. Moreover, organ destruction was more effectively inhibited by simultaneous injections of patient-derived IgG1 and IgG4 than by injection of patient-derived IgG1 alone. These observations suggest that IgG4 antibodies act against pathogenic IgG1 antibodies. Fujimoto et al. reported that in patients with stage I squamous cell lung cancers, IgG4-positive cell infiltration around the tumour in the resected lung specimens corresponded with a favourable prognosis24. These phenomena are compatible with our findings that IIPs with IgG4-positive cell infiltration showed a tendency toward a better prognosis and that IPF with IgG1-positive cell infiltration had a significantly worse prognosis. IgG1 and IgG4 immunostaining may be beneficial for IIPs because it may predict prognosis and inform therapeutic management decisions.The pathogenicity of IgG4-RD remains to be elucidated. It also remains to be determined whether IgG4 antibodies are active in the pathogenesis of IgG4-RD. IgG4 cannot activate the classical complement pathwayThis study has several limitations. The nationwide, cloud-based database does not include serum IgG or IgG4 levels; therefore, we obtained these from the clinical records of each institution. Almost all institutions in this study did not routinely test for serum IgG and IgG4; thus, we could only obtain a small sample number. Additionally, the study was not large enough to reach definite conclusions on the prognosis of IIPs with or without IgG4-positive cell infiltration. Despite these limitations, to the best of our knowledge, this is the first report describing IgG-, IgG1-, and IgG4-positive cell infiltration in SLB specimens for IIPs diagnosed by a centralised MDD.In summary, we revealed the prevalence of IgG4-positive cell infiltration in SLB specimens from patients with IIPs in Japan. The prognosis of IIPs with IgG4-positive cell infiltration tended to be better than those without IgG4-positive cell infiltration. Furthermore, IPFs with IgG1-positive cell infiltration had a significantly worse prognosis than those without IgG1-positive cell infiltration. Overall, evaluations of the degree of IgG1-positive cell infiltration may be prognostically useful in cases of IPF.25. We used a nationwide cloud-based integrated database of IIPs after centralised MDD. Details of the database have been described previously25. Information on 524 patients who underwent SLB from April 2009 to March 2014 was collected from 39 institutions throughout Japan. The cloud-based database was constructed including clinico-radiolo-pathological data. Web-based MDD was performed using the database.This study is a secondary survey of data from a retrospective studyIn this study, we enrolled 88 patients from five institutions for whom re-pathological analysis was possible. We reviewed the glass slides of SLB from the 88 cases. The institutional review board approved the study protocol  and each institution approved the study protocol . This study was performed in accordance with the Declaration of Helsinki and its subsequent amendments. The need for obtaining patient written informed consent was waived, owing to the retrospective nature of this study.Clinical information was obtained from the database for each patient. Although serum levels of IgG, IgG1, and IgG4 were not included in the database, the serum level of IgG4 for 24 of the 88 patients was obtained from the clinical records from each institution. The incidence of acute exacerbation and lung cancer was also obtained from the database. Inadequate items in the database were excluded.26.In our cohort, non-IIPs such as sarcoidosis, hypersensitivity pneumonia, or collagen vascular disease-associated interstitial pneumonia were excluded by MDD. Clinical, serologic, and morphological domains were evaluated based on the criterion of IPAF27.Sex, age, physiological  variables, and GAP index were calculated in the IPF groupClinical characteristics of IgG4-positive or negative IIPs, as well as IgG1-positive or negative IIPs, were analysed. In addition, we analysed clinical characteristics of IgG4-positive or negative IPF, as well as IgG1-positive or negative IPF.28 of IPF: definite UIP, possible UIP, or inconsistent with UIP pattern.All high-resolution computed tomography (HRCT) chest images obtained within three months of the SLB were analysed. The radiologists determined the HRCT pattern of IIPs according to the 2011 guidelines28: definite UIP, probable UIP, possible UIP, and not UIP pattern. The pathologists also determined the histological patterns of IIPs according to the statement of classification for IIPs29.The pathologists classified the samples from the SLB according to the 2011 guidelines of IPF classification30. IgG1-positive cells were scored in the same way.In this study, SLB specimens were stained with haematoxylin–eosin and immuno-stained for IgG, IgG1, and IgG4. IgG immunohistochemical staining was performed using monoclonal IgG antibody . IgG1 and IgG4 immunohistochemical staining were performed using polyclonal antibodies against IgG1 and IgG4 . The areas with the highest density of IgG4-positive cells, identified using immunostaining, were observed under a low-power field. A trained pathologist (T.U.) counted the IgG4-positive cells per HPF. IgG-positive cells/HPF and IgG1-positive cells/HPF were also counted in the same areas where IgG4-positive cells were evaluated. Representative pathological findings are shown in Supplementary Fig. U test or unpaired t-test was used to compare continuous variables between the two groups, the χ2 test or Fisher’s exact test was used to compare categorical variables. The OS, median, and 95% CIs were determined using the Kaplan–Meier method. The differences between groups were compared using the log-rank test. The univariate Cox proportional hazards regression analysis followed by a multivariate analysis was used to identify the determinants of a high risk of death. Correlations between the groups were examined using the Spearman’s rank correlation test. Variables with a p-value < 0.05 in the univariate analyses were considered for inclusion in the multivariate model. Statistical analyses were performed using StatFlex® Version 7.0 . Statistical significance was established at a p-value < 0.05.Continuous data are presented as median and range, and categorical data are presented as a numerical value in each group. While the Mann–Whitney This study was approved by the Ethics Committee of the Shinshu University School of Medicine , Hamamatsu University School of Medicine , Toranomon Hospital , Prefectural Chubu Hospital  and Kurume University School of Medicine . This study was performed in accordance with the Declaration of Helsinki and its subsequent amendments. The need for obtaining patient written informed consent was waived, owing to the retrospective nature of this study .Supplementary Information.


The production and utilization of concrete and concrete-based products have drastically increased with the surge of construction activities over the last decade, especially in countries such as China and India. Consequently, this has resulted in a corresponding increase in the energy used for the production of ready-mixed concrete. One approach to reduce the cost of concrete manufacturing is to reduce the energy required for the manufacturing process. The main hypothesis of this study is that the power required for mixing the concrete can be reduced through the use of mineral admixtures in the mix design. Optimization of energy consumption during mixing using admixtures in concrete manufacturing is the predominant focus of this article. To achieve this objective, power consumption data were measured and analyzed throughout the concrete mixing process. The power consumption curve is the only source to distinguish the behavior of the different materials used in the concrete in a closed chamber. In the current research, fly ash and ground granulated blast-furnace slag (GGBS) were used as mineral admixtures to produce ready-mixed concrete. The experimental study focused on the influence of GGBS and fly ash on power consumption during concrete mixing. The results indicated that the use of a higher content of GGBS is more beneficial in comparison to the use of fly ash in the mix due to the lower mixing time required to achieve homogeneity in the mixing process. It was found that the amount of energy required for mixing is directly related to the mixing time for the mix to achieve homogeneity. Energy consumption is a major issue that is faced globally in the current scenario. In all manufacturing industries, identifying and controlling the processes that consume more energy is a key element in optimizing energy consumption, which will save energy and increase cost-efficiency. Before applying all cost-saving methods to a single factory, all cost-saving methods should be carefully analyzed, because all manufacturing processes require different potential energy, resulting in different energy consumption and material savings ,2,3. ThrCazacliu  explaineMixing is the most important stage in concrete manufacturing and is one that consumes the most energy. A ready-mixed concrete factory produces different types of concrete. Mixing plays a vital role in distinguishing different types of concrete. Nowadays, the manufacturing of SCC and HPC has increased due to emerging high-rise buildings and large structures. The power consumption curve obtained during the mixing of concrete gives a better understanding of the microstructural evolution in the concrete mixture . Mixing Mixing is an important operation that eliminates the inhomogeneity in a mixture. ASTM 305 is commonly used all around the world for mixing procedures . Two imp3 of concrete can be manufactured per day in one ready-mixed concrete plant. In the future, this may increase due to the development of urbanization. In the manufacture of ready-mixed concrete, ingredients are added at specific intervals. Cement, fine aggregate, coarse aggregate, fly ash, GGBS, and water are added one by one into the mixing chamber. As the ingredients are loaded into the mixing chamber, power consumption will increase. The maximum power consumption is obtained when all components are loaded. The first peak is obtained when the mixture of dry ingredients reaches homogeneity in the dry state. After adding water, when a homogeneous mixture is obtained in a wet state, the second peak is reached [In high-speed construction, concrete production requires more attention because there is no optimal time for concrete mixing . In the  reached ,11. AftePower consumption is an important factor in determining the different stages of concrete mixing in the mixing chamber . The powThe gaps identified from the above literatures are as follows: The power consumption required for the mixing of the concrete has not been studied for the ready-mix concrete. The impact of the admixtures, workability, and density of concrete on power consumption during mixing has not been explored.3 of concrete was manufactured for each batch. The total quantity of concrete required for one truck may vary from 6 to 8 m3, and it takes approximately 1 min to mix 1 m3 of concrete in the mixing unit. Three grades of concrete, M25, M30, and M40 were studied. From each grade, four to five mixes were produced by replacing fly ash and GGBS in different percentage, and its energy consumption during mixing was measured and the energy curve plotted. The raw materials used were cement, fine aggregate, coarse aggregate, fly ash, GGBS, and water. All raw materials were stored in different storage locations in the RMC plant, as shown in In this experimental investigation, energy consumption was measured during the mixing of concrete manufactured in a ready-mixed concrete plant. The mixing motor was connected to the power meter, where the voltage and current consumed during mixing were recorded. The power was calculated by the formula P = V × I. In the ready-mixed concrete plant, 1 mGrade 53 ordinary Portland cement meeting IS 269-2015 (Indian Standard) was used to produce concrete in the RMC plant. Fly ash, conforming to IS 3812-2003, was obtained from the Ennore thermal power plant in India, and was used as a mineral admixture. Another mineral admixture, GGBS, conforming to IS 16714:2018, was also used. M-sand and C-sand were used as fine aggregate and coarse aggregate of size 12 mm and 20 mm, respectively, both the aggregates conforming to IS 383-2016. They were obtained from the locally available market. Both types satisfy the requirements of the Indian standard that complies with grading zone II. Crushed granite stone was used as coarse aggregate with sizes of 12 mm and 20 mm. This was obtained from the local dealers of Chennai, and it satisfies the Indian standard requirement. The two chemical admixtures used were Polycarboxylate ether (PCE) and Sulphonate naphthalene formaldehyde (SNF), obtained from CBS Chemicals, and these were used as retarding Superplasticizers. The mix design was calculated according to the Indian standard method by adopting mix code IS 10262-2019. The batching and mixing of the concrete were carried out according to the code IS 4925-2004. The entire manufacturing was carried out in a ready-mixed concrete plant. The Mix compositions and specifications are shown in The entire power meter readings during the mixing process were recorded, as shown in 3 of concrete, i.e., one batch. The total number of peaks represents the total quantity of the concrete manufactured. It can be seen from the curve that the initial reading starts at zero, and as the material is loaded, the power consumption will increase [The curve was plotted against time versus power consumption. Each peak represents the mixing of 1 mincrease . Energy The slump test is used to measure the workability of concrete. Workability tests are usually performed on all batches of concrete in the ready-mixed concrete plant to check the uniformity of the different batches of concrete manufactured. The slump test will show different values for the same concrete manufactured in the morning and afternoon. The amount of a chemical admixture depends on the slump value of the first batch of concrete produced. After the concrete is discharged from the mixer, the freshly cast concrete is directly composed from the outlet of the truck mixer to perform a slump test. The entire test is carried out in the ready-mixed concrete plant. Furthermore, this research has been extended to correlate power consumption with a slump value, which has not been carried out previously for ready-mixed concrete. The measurement of the slump value is shown in The power consumption for the various grades of concrete and the slump value for the corresponding mixes are shown in It can be seen from From the above observation, we can clearly understand that density is an important factor in power consumption, but it is not the only factor that controls power consumption. The M25- and M30-grade concrete shows similar characteristics in power consumption, i.e., lower density mix consumes minimum power and higher mix consumes maximum power. In higher-grade concrete (M40), the results show the opposite characteristics, namely, high-density concrete consumes the least power, while low-density concrete consumes the most power ,43, thouIn In The mixtures C1 and C2 have similar compositions and slump values, but the power consumption of C2 is abridged. This reduction may be due to the use of SNF superplasticizer. The composition of the mixtures B4, B5, A2, and A3 are similar, but the purpose of the water-reducing agent is different. SNF is used as a chemical mixture in A3 and B5, which is further explained in The amalgamation of powder content for each concrete has a different effect on power consumption. In most cases, the combination of cement and fly ash consumes more power during the mixing process, while the combination of cement and GGBS consumes the least power ,26,47,48In Among C1, C2, and C3, which have similar compositions but differ in the type and dosage of superplasticizer, C2, which contains SNF as a superplasticizer, consumes minimum power during mixing. With the combination of fly ash and cement, the w/p ratio increases and mixture C5 consumes the maximum power. Of the mixtures C4 and C6, mixture C4, consisting of cement and fly ash, consumes the maximum power, while mixture C6, composed of cement and GGBS, consumes the minimum power.The enlargement of the particle size is called granulation, and it depends on the powder used in the mixing process ,51,52. SThe change in power consumption is primarily a result of the different materials included to the concrete mixture. The mineral admixtures used in concrete have different chemical and physical properties. As a result, all materials act differently. Identifying the materials that can minimize energy consumption and using them in concrete production can reduce the energy required for the manufacturing process.–A maximum fly ash content of 22% increases the power consumption by 19.27–20.28%. Inversely, a minimum fly ash content of 16–18% decreases the power consumption by 1.3–9.83%. A GGBS content of 35–44% increases the power consumption by 3.8–20.8%.–For the slump value, 16–18% of fly ash increases the value by 12.5–25%, and hence there is a decrease in the power consumption. A fly ash content of 22% decreases the slump by 11.8 to 15.8%, and there is a corresponding increase in the power consumption by 19.27 to 20.28%. There is an increase in the slump value of 6.7–16.8% for 35–44% GGBS content.–It is obvious from the findings that the maximum use of fly ash will consume more energy to achieve homogeneity and increase the energy required for concrete production.–For concrete containing fly ash, its curve profile, which is visible in the energy consumption curve, rises and falls unevenly due to the formation of granules when fly ash and GGBS are mixed with water.–The quality of the mixing depends upon the degree of homogeneity attained at the end. The homogeneity obtained depends on several factors, such as the properties of single particles, the properties of bulk particles, operating conditions, and mix design.–It was found that an increase or decrease in water content may also lead to an increase or decrease in power consumption. The texture of the aggregate and the mineral admixtures added to the concrete can cause internal abrasion on the surface of the mixing drum.–Aggregate and mineral admixture wear and particle collisions are other factors leading to increased power consumption. The mixer drum has difficulty blending certain materials because hard particles prevent blending and overcome the torque, so the drum consumes excess power in order to rotate. This could be one of the key reasons for the difference in power depletion when using different mineral admixtures.Energy optimization in all areas is the ultimate goal in the protection of our natural resources. It can be seen from the above results that the maximum use of powder content has an impact on the energy consumption, thereby achieving the homogeneity of the concrete during the mixing process. However, the following conclusions were drawn based on the major findings of this study:


Recycled fine aggregate (RFA) produced from concrete waste is commonly used in the construction industry; however, its use for structural concrete members has not been extensively studied. Moreover, its durability in a drying–wetting cycle environment still needs to be examined. In this study, the intrusion process of chloride in concrete under the drying–wetting cycles is experimentally characterized. Chloride penetration tests are carried out on concrete with the incorporation of different RFA replacement rates and mineral admixtures . The results show that the chloride penetration of recycled fine aggregate concrete (RFAC) is dependent upon the performance of the concrete itself, while the deterioration of chloride ion erosion resistance is due to the combined action of the replacement rate of RFA and the drying–wetting cycles. The incorporation of RFA degrades the properties of RFAC owing to its drawbacks in the degradation of interfacial properties of RFAC. Exposure to the drying–wetting cycle environment causes the content of free chloride ions in RFAC to increase initially before decreasing with the erosion depth, thereby showing an obvious convection zone and diffusion zone. The incorporation of the mineral admixture can effectively improve the compactness of the concrete microstructure and make concrete less susceptible to chloride ions ingress. RFAC mixed with 15% fly ash and 10% silica fume has a comparable resistance to chloride penetration as a natural aggregate concrete, which is a feasible method for the application of RFA. Concrete is in great demand worldwide in the construction industry. The natural aggregate used for traditional concrete is expensive and the mining process is environmentally unfriendly. The large amounts of construction waste produced every year cause great environmental stress. Therefore, it is necessary to find alternatives to the aggregate. The production of recycled aggregates using waste concrete is becoming a viable option to both solve the problems of concrete production and become environmentally friendly ,2. ThereRecycled coarse aggregate is increasingly accepted in codes for structural use, while the usage of recycled fine aggregate (RFA) in structural concrete is restricted . Many scHowever, the structure is susceptible to chloride intrusion and its durability is greatly affected. As a result, steel bars corrode and concrete cracks, resulting in structural deterioration and advanced failures. Even worse, studies have revealed the negative impacts of recycled aggregate on chloride resistance in concrete prepared with it, showing a direct relationship between chloride permeability coefficient and RFA substitution . Alterna− ingress. Bai et al. [The drying–wetting cycle is the key factor affecting the durability of the concrete exposed to the deicing salt areas and marine environments . Comparei et al.  observedi et al.  observedAlthough RFA is commonly used in the construction industry, its use as a structural concrete member has not been extensively studied. Moreover, its durability in a drying–wetting cycle environment still needs to be further studied. The mechanical properties and durability of concrete are both influenced by its composition and chemical additives. The influence of the composition is well-known and will not be repeated. The addition of admixtures can make beneficial modifications to the performance of concrete. Therefore, it is feasible to prepare concrete structures with high mechanical properties and chloride resistance. In this case, RFAC with different RFA mass fractions  and six types of concrete with various mineral admixtures and 100% RFA were prepared, and its chloride penetration process was investigated using a drying–wetting cycles test. In other words, the influence of the RFA replacement rate on the chloride penetration of RFAC and the influence of mineral additives on improving the chloride resistance of RFAC were studied. Silica fume and fly ash are the most commonly used mineral additives in concrete since they produce better workability and higher chloride resistance in the concrete. The improvement effect of these two mineral additives on the chloride resistance of RFAC was analyzed, and the application of the concrete prepared with RFA in a drying–wetting cycle environment is discussed. The combined effect of the drying–wetting cycle and chloride erosion on the properties of RFAC has not yet been thoroughly studied and represents the main objective of this study.Ordinary Portland cement (OPC) and mineral admixtures were used as cementing materials in the study. Two kinds of mineral admixtures, silica fume (S) and fly ash (F), were selected to replace a portion of the cement to improve the performance of RFAC. The chemical compositions of the cement, silica fume, and fly ash are presented in α, where α is the RFA replacement rate . For example, R0 is the concrete with 0% RFA, which is the natural aggregate concrete and serves as the control group. Furthermore, R25 is the concrete with 25% RFA. On the other hand, mixtures were prepared by 100% RFA and a different number of mineral admixtures to investigate the improvement effect of mineral admixtures on the performance of RFAC, which are designated as RFβ, RSγ, and RFβSγ, respectively. R, F, and S stand for RFA, fly ash, and silica fume, respectively. Alternatively, β and γ stand for the mass replacement rate of fly ash and silica fume, respectively. According to previous studies [A total of 11 concrete mixtures were prepared for this study. On the one hand, four kinds of RFA replacement rates were selected to investigate the influence of the RFA replacement rate on the performance of RFAC: 0%, 25%, 50%, 75%, and 100%, respectively. Mixtures prepared with OPC and RFA were designated as R studies ,23, two − permeability coefficient test. Meanwhile, 99 cubes, each 150 mm in size, were prepared for a free chloride content test.A total of 165 cubes, each 150 mm in size, were cast for compressive strength testing, of which 99 cubes were used for compressive strength testing before the drying–wetting cycles, while 66 cubes were used during the drying–wetting cycles. Simultaneously, 99 cubes, each 100 mm in size, were cast for the porosity test, of which 33 cubes were used for the porosity test before the drying–wetting cycles, while 66 cubes were used during the drying–wetting cycles. A total of 33 specimens with dimensions of Φ100 mm × 50 mm were prepared for the ClAfter mixing, the specimens were collected after 24 h and transferred to a standard curing room  for 28 days. The compressive strength of the concrete is carried out according to the Chinese standard GB/T 50081-2019 .The specimens for the drying–wetting cycles are sealed on five sides with an epoxy polyurethane-based coating, with only the top side exposed so as to ensure the diffusion of chloride ions in only one dimension. The drying–wetting cycles test is programmed to investigate the chloride penetration of the concrete. Specimens were first immersed into sodium chloride solution with a 10% concentration for 21 h  is one of the main methods to load transfer in concrete. Compared with natural aggregate concrete, the ITZ of RFAC is weaker due to the presence of old adhered mortar from RFA. Alternatively, the extra water added due to the high-water absorption of RFA would accumulate in the ITZ during the mixing process and affect the performance of the ITZ. There are some inherent microcracks in the ITZ, which propagate continuously due to the high-stress concentration at the crack tips when the concrete is subjected to load. It follows that the presence of weaker ITZ in RFAC results in lower concrete strength compared with natural aggregate concrete. The concrete with a high RFA replacement rate has more ITZ between the aggregate and the old-adhered mortar; thus, its compressive strength is lower. The effect of the drying–wetting cycles promotes the propagation of inherent microcracks in the ITZ and further reduces the compressive strength of RFAC.− permeability coefficient of RFAC after 28 days of curing. As the replacement rate of RFA increases, both the porosity and Cl− permeability coefficient of the concrete increase gradually. As shown in − permeability coefficient of RFAC. The Cl− permeability coefficient of R100 is 1.36 × 10−12 m2/s, which is twice that of R0. However, the Cl− permeability coefficients of RF10S5 and RF20S10 are 67.6% and 53.2% that of R100, respectively, and 137.3% and 108.1% that of R0, respectively.− permeability coefficient, which is an effective method to improve the performance of concrete.This phenomenon further confirmed the negative effect of RFA on the properties of RFAC. In the mixing progress, the addition of extra water increased the actual water–cement ratio of RFAC, which led to the deterioration of the compactness and the high porosity of RFAC. A large amount of old mortar adhered to RFA led to its own high porosity, which also increased the porosity of RFAC. This result further verifies the positive effect of mineral admixtures on the properties of RFAC. As previously detailed ,28, the − permeability coefficient, as shown in − permeability coefficient, while concrete with a higher porosity has a worse chloride resistance. This also confirms the previous understanding that the porosity of concrete is not negligible and has a significant impact on the chloride resistance of concrete [− ingress than natural aggregate concrete. In addition, the presence of old mortar also weakens the structural and mechanical properties of the ITZ of RFAC. Therefore, RFAC with a looser pore structure is more susceptible to chloride ingress compared with natural aggregate concrete.The porosity of RFAC is linearly related to the Clconcrete ,30. In tThe porosity of RFAC exposed to 0 and 36 drying–wetting cycles is shown in The durability of RFAC depends on the performance of the concrete itself. The incorporation of RFA degrades the properties of concrete because it increases the porosity and degrades the interfacial properties of concrete. The drying–wetting cycle magnifies these drawbacks of RFAC, resulting in higher porosity and worse interfacial properties. In this regard, there are more paths in the recycled concrete for chloride ingress, and the content of chloride ions inside the concrete increases.These findings indicate that the incorporation of a mineral admixture  reduces the accumulation of free chloride at the exposed surface and delays the diffusion of chloride ions into the interior. This phenomenon is likely due to the modified pore structure of the concrete with a mineral admixture, which can lead to the reduction of the effective diffusion coefficient of chloride ions. Consequently, the chloride penetration process in RFAC with a mineral admixture is much slower compared with that of other concretes during the drying–wetting cycles; therefore, the chloride ion concentration in the concrete is lower.As illustrated in k of the free chloride content is shown in k is defined as:cR0 is the free chloride content of R0 after 36 drying–wetting cycles and The percentage difference k are all negative. The value of k in the diffusion zone between R0 and the other concretes with different RFA replacement rates is larger than that in the convection zone, indicating that the negative effect of the RFA replacement rate on the diffusion region is greater than that on the convection region. Interestingly, except for RF10S5 and RF20S10, the absolute values of k at 9–15 mm for mixtures are almost greater than those at 0–6 mm. This reveals that fly ash and silica fume allow more beneficial modifications to the chloride resistance of the concrete in the convection zone than in the diffusion zone. However, the composite incorporation of the two admixtures has the same improvement effect on chloride penetration resistance in these two respective zones of concrete. In particular, the absolute value of k for RF20S10 at all depths is the smallest, and it is inferred that the chloride penetration resistance is close to R0.Considering that the free chloride content of concrete is small at depths of 18, 21, and 24 mm, it was not included in the table. The free chloride content of R100 at the same depths is the largest in all concrete, while that of R0 is the smallest after the same drying–wetting cycles. As illustrated in The microstructures of the concrete specimens are the fundamental reason for the performance of concrete. SEM images of RFAC with different RFA replacement rates after 36 drying–wetting cycles are shown in As shown in Loose structure and poor quality of ITZs are the essential reason for the low compressive strength and poor chloride penetration of RFAC. The SEM images of RFAC with 100% RFA and a mineral admixture after 36 drying–wetting cycles are shown in 2 in the interfaces between the aggregate and mortar and generates more C-S-H gels, which enhances the bonding property of the interfaces and improves the interfaces.The above phenomena are related to the hydration reaction of the concrete, which is promoted by incorporating either fly ash or silica fume. The performance improvement of ordinary concrete by adding the mineral admixtures is mainly due to the pozzolanic reaction, while the mineral admixture has dual effects on the recycled concrete, such as microaggregate filling and the pozzolanic reaction . The micThis paper investigates the chloride penetration of RFAC exposed to drying–wetting cycles. The chloride ion content, compressive strength, and porosity of RFAC, with different RFA replacement rates, are explored.(1)Under the drying–wetting cycling conditions, there are obvious convection zones and diffusion zones for the free chloride profiles. The depth of the convection zone is about 5 mm, and it increases as the number of cycles increases. The negative effect of the RFA replacement rate is greater on the concrete diffusion zone than on the convection zone.(2)The reduction in the compressive strength of RFAC is larger as the number of cycles or the RFA replacement rate increases. The 28-day compressive strengths of R25, R50, R75, and R100 are 3.3%, 5.8%, 17.0%, and 22.1% lower than that of R0, respectively. The compressive strength of RFAC made with 100% RFA decreases by 19.6% after exposure to 36 drying–wetting cycles. The 28-day compressive strength of concrete has a linear relationship with the RFA replacement rate.(3)− permeability coefficient and compressive strength.The incorporation of RFA increases the porosity of RFAC and causes its durability to deteriorate. Concrete with a higher RFA displacement rate has a higher porosity during the drying–wetting cycles. Before the drying–wetting cycles, the porosity of R100 prepared with 100% RFA was 14%, which is 68.7% higher than that of R0, while the porosity of R100 reached 20% after 36 drying–wetting cycles. The porosity of RFAC is linearly correlated with the Cl(4)The incorporation of fly ash or silica fume greatly improved the performance of RFAC, especially the composite incorporation of 20% fly ash and 10% silica fume. The properties of concrete prepared with 100% RFA, 20% fly ash and 10% silica fume are basically comparable to those of natural aggregate concrete, while the resistance to chloride penetration is also comparable, which is a feasible method for the application of RFA.(5)SEM analysis showed that the bonding strength at the ITZ of RFA in RFAC is weaker than that of natural aggregate concrete. After the drying–wetting cycles, there were more pores and microcracks in the microstructure of RFAC, which was the reason for the deterioration of the chloride penetration resistance. The incorporation of mineral admixtures improved the interface and enhanced the performance of the concrete.


Acute bronchitis is a self-limiting disease, characterized by mild constitutional symptoms and a cough lasting two to three weeks. The disease usually occurs secondary to viruses; therefore, only symptomatic and supportive care is advised for the patients. Despite the recommended guidelines, most patients are prescribed antibiotics. Here, we present a case of a 38-year-old female who presented to the hospital with a sudden onset of severe epigastric pain. The patient recently started a 10-day course of doxycycline for acute bronchitis. She was admitted, evaluated, and diagnosed with doxycycline-induced esophagitis, and managed accordingly. This report highlights how excessive use of antibiotics is leading to adverse effects, antibiotic resistance, increased health care costs, and invasive testing. It also emphasizes the importance of antibiotic stewardship. Acute bronchitis is defined as an acute inflammation of the large airways without any signs of pneumonia. It is characterized by mild constitutional symptoms and cough (productive or non-productive), which typically lasts for two to three weeks. The disease can be caused by viruses (most common), allergens, and irritants. Acute bronchitis is a self-limiting disease; therefore, only supportive and symptomatic treatment is recommended .In contrast to the recommended guidelines for uncomplicated acute bronchitis, many of these patients are still prescribed antibiotics. This excessive and unnecessary use of antibiotics has resulted in increased antibiotic-associated adverse effects, antibiotic resistance, and health care costs . Herein,A 38-year-old female with no past medical history presented to the emergency department with epigastric pain for two days. The pain was described as a squeezing, sharp pain that radiated to her back. According to the patient, the pain began suddenly with no inciting factors. Twenty-four hours later, her symptoms progressed and the pain intensity worsened to a 10/10. She denied any fever, chills, melena, or hematemesis. Her last menstrual period was a few days prior to presentation, and it was regular. Of note, she was recently given a 10-day course of Doxycycline, and her last dose was the night prior to the onset of her symptoms. She denied any recent travel, dietary changes, work-related exposures, or over-the-counter non-steroidal anti-inflammatory drug (NSAID) use.On presentation, the patient was afebrile. She had a respiratory rate of 24 breaths per minute, a normal heart rate, and a blood pressure of 101/63 mm Hg. Her physical exam was remarkable for epigastric tenderness to palpation. Her complete blood count was remarkable for a white blood cell count of 12.7 and a hemoglobin of 10.7 mg/dL. A complete metabolic panel, lactate, and lipase were unremarkable. Troponin and beta-human chorionic gonadotropin were negative. An electrocardiogram demonstrated normal sinus rhythm. A chest X-ray was negative for any findings. The abdominal X-ray demonstrated a non-obstructive bowel gas pattern. The CT abdomen/pelvis was negative for any pathology.She was started on pantoprazole 40 mg IV twice daily, paracetamol and morphine for pain, and ondansetron for nausea. The patient underwent esophagogastroduodenoscopy (EGD) and was found to have LA grade D esophagitis with oozing as shown in Figures Acute bronchitis is among the top ten most common illnesses among outpatient clinics in the United States . It is aClostridium difficile infection [This excessive use of antibiotics has resulted in more adverse effects, such as allergic reactions, nausea, vomiting, and nfection . Our casnfection .Apart from the adverse effects, inappropriate antibiotic use has led to increased antibiotic resistance, which has resulted in an epidemic of antibiotic-resistant infections, further resulting in increased morbidity, mortality, and economic costs due to infections . The deaAntibiotic stewardship is an important means of limiting antibiotic resistance. The first time the term "stewardship" was used in reference to antibiotics was in 1996, in an article in New Horizons . The maiThe core elements of a successful antibiotic stewardship program are: strong leadership, tracking of antibiotic use, regular reporting of antibiotic use and resistance, educating providers on use and resistance, and specific interventions . The speMoreover, according to a study done by Fishmann, patients in the antibiotic stewardship group were three times more likely to get appropriate treatment as per guidelines; they were twice as likely to be cured and they were 80% less likely to have treatment failure, as compared to the patients receiving standard care [Hence, antibiotic stewardship, which has evolved immensely over the past 20 years and now has become a global drive, plays a key role in optimizing antibiotic use. However, there are still some hindrances to its success, such as not enough trained personnel, limited structural and time resources, and variable cultural determinants .Therefore, in order to achieve a long-lasting change in prescribing behaviors and a successful reduction in unnecessary use of antibiotics, a global standard for the successful implementation of these programs should be set, and physicians and patients should realize the importance of antibiotic stewardship and take every step to achieve this goal for a better future.Acute bronchitis is a self-limiting disease and does not warrant the need for antibiotics. Despite this, antibiotics such as doxycycline are commonly prescribed for it in outpatient settings, leading to multiple adverse effects, i.e., pill esophagitis as seen in our case, requiring invasive intervention. Inappropriate antibiotic prescribing practices become a seed for antibiotic resistance and the spread of antibiotic-resistant infections, leading to increased morbidity, mortality, invasive testing, length of stay, health care expenditure, and poor outcomes. Antibiotic stewardship programs play a pivotal role in medicine, by improving patient outcomes, combating antibiotic resistance, and reducing the overall health cost. Therefore, strategies should be made for the successful implementation of the programs globally and for achieving significant results.


The Cone Health stewardship team has collaborated with clinical pharmacists and infectious diseases physicians to define a process to optimize antibiotic therapy. This process involves microbiology calling a pharmacist with newly positive blood cultures, and the pharmacist notifies the attending physician with the results and evidence-based treatment recommendations. We transitioned from BCID to BCID2 in August, 2021. As CTX-M (marker for extended spectrum beta-lactamase production) was not a target on BCID, we were interested in how the addition of this marker could improve care in this subset of patients.The importance of effective antibiotic therapy for the treatment of bloodstream infections has been well described. Rapid diagnostic testing platforms like the BioFireProcedure for Positive Blood Culture Workup and NotificationTreatment Recommendations for Selected OrganismsS. aureus, P. aeruginosa, CTX-M, KPC, OXA-48 like, IMP, VIM, NDM, and vancomycin resistant enterococci. An effective antibiotic was defined as an antibiotic with in vitro activity to the organism, and an optimal antibiotic was defined as the preferred agent based on institutional guidelines. For CTX-M isolates, we compared effective and optimal times to a historical control of ceftriaxone resistant enterobacterales and analyzed by student’s t-test.From August 2021 - March 2022, the times to administration of effective and optimal antibiotics were evaluated in patients with the following BCID2 organism and resistance gene targets identified: The combined mean time from BCID2 to administration of effective antibiotics = 1.2 hours (range 0-7.9 hours) and to optimal therapy =7.6 hours (range 0 – 113.8 hours). Prior to the BCID2 transition, patients found to be growing ceftriaxone resistant enterobacterales had an average time to optimal antibiotic administration of 17.7 hours, which improved to 2.8 hours after BCID2 implementation (p=0.0041).Time to Effective and Optimal Antibiotics after implementation of BCID2 (August 2021 – March 2022)Time to Effective and Optimal Antibiotics for Ceftriaxone Resistant Enterobacterales Prior to BCID2 Implementation (January 2021 - July 2021)® FilmArray® coupled with antibiotic stewardship team support can help optimize time to effective and optimal antibiotic therapy in bloodstream infection. The addition of the CTX-M target to BCID2 was a helpful addition to the panel which allowed for decreased time to optimal antibiotic therapy.BioFireAll Authors: No reported disclosures.


Excellent research in all fields, including spine surgery, exists in many different regions and languages. This study seeks to determine the relative number of spine related peer-reviewed publications throughout the world based on language.Peer-reviewed publications from the eleven most prolific languages in regard to both the number of peer-reviewed spine publications indexed in PubMed and total peer-reviewed publications from 1950-2020 were identified in PubMed.29,711,547 peer-reviewed publications were analyzed for the languages of interest with 870,404 (3.0%) of those being spine related peer-reviewed publications. Between 1988 and 2019, non-English language peer-reviewed publications decreased annually for both all peer-reviewed publications and spine related peer-reviewed publications by 44% and 36%, respectively. All medical and spine specific peer reviewed publications in English compared to non-English publications have increased by 7.22 and 6.35 times since 1988, respectively. While the ratio of non-English to English spine related publications decreased in all eleven countries, the percentage of the number of spine specific publications written in Chinese (462%), Portuguese (378%), and Spanish (88%) have increased by the listed percentages.While the proportion of peer-reviewed publications in the field of spine surgery written in English have increased over the past several decades, there are many non-English language peer-reviewed publications each year, particularly in Chinese. Although the rapid increase in the proportion of English spine related publications is beneficial to English speaking physicians and researchers, further research is necessary to understand the impact on non-English speaking physicians and researchers. The number of non-English journals and their impact is declining within many scientific fields When scientific breakthroughs are not published in the English language, newfound knowledge remains inaccessible to English-only speaking scientists. This impasse leads to ‘lost’ science which may cause delays in potential advances in a field. By elucidating and developing a strong understanding of the knowledge present within the realm of ‘lost’ science, specifically in the field of spine research, there exists the potential to improve patient-outcomes worldwide.An in-depth literature review was conducted using PubMed to identify all peer-reviewed publications based on the language they were written in. The search results were filtered to isolate articles from 1950-2020. All data analysis using Microsoft Excel Version 16.16.18 for macOS.The languages in this study were selected based on the total number of peer-reviewed publications in PubMed. The top 20 non-English languages publishing in PubMed were found using the search algorithm: (“INSERT LANGUAGE HERE”[Language]). The top 20 were further analyzed by the number of peer-reviewed publications related to the spine using the following PubMed search algorithm: (“INSERT LANGUAGE HERE”[Language]) AND ((spine) OR (disc herniation) OR (radiculopathy) OR (spondylolisthesis) OR  OR (scoliosis) OR (myelopathy) OR (kyphosis) OR (lordosis) OR ('pelvic incidence') OR (Odontoid) OR ('degenerative disc disease') OR (lamina) OR  OR (vertebrae) OR (vertebra) OR (pedicle) OR ('spinous process') OR ('transverse process')). Peer-reviewed publications yielded from this search will be referred to as “spine publications.” Ultimately, the top 10 non-English languages with peer-reviewed publications in spine were selected: Chinese, Czech, French, German, Italian, Japanese, Polish, Portuguese, Russian, and Spanish. (“INSERT LANGUAGE HERE”[Language]) was used to query for all peer-reviewed publications in a specific language.Peer-reviewed publications were separated by year of publication between 1950-2020. Individual languages were analyzed based on total number of publications, number of spine publications, and percentage of publications. Further analysis of spine data included calculations of percent spine publications relative to all peer-reviewed publications for a given year. Ultimately, the publication data for all non-English languages were combined and examined relative to the publication data for the English language.Between 1950 and 2020, a total of 29,711,547 peer-reviewed publications were analyzed for the languages of interest , with 870,404 (3.0%) of those being spine publications. As shown in The trends for annual number of English and non-English spine publications from 1950 to 2019 are shown in When looking at spine publications in non-English languages, from the years 1950-2000, German, French, Russian, and Japanese were generally the most common non-English language of publication. However, around the early 2000s, Chinese jumped to become the most common non-English language for spine publications. .Fig. 2SpThis study investigates the scale of ‘lost’ science that exists across countries and language in the field of spine surgery. Given the ease of access to information in the modern age, research accessibility depends more on the language of publication than on the country of origin. Between 1950 and 1953, 96% of peer-reviewed publications were in English. Soon after, peer-reviewed publications began to appear in non-English languages. In the early 1960s, the majority of peer-reviewed publications related to the spine were in non-English languages. However, over the next three decades, peer-reviewed publications on spine were increasingly published in English . EnglishWith 111,872 peer-reviewed spine publications since 1950 having been written in a non-English language, there is a huge volume of peer-reviewed spine publications that are otherwise inaccessible to English-only speaking scientists and surgeons; yet, based on the rate of increasing number of peer-reviewed spine publications in English, it seems that there has been an international effort to make English the new universal language. However, with data showing that some languages like Chinese, Portuguese, and Spanish are continuing to increase their spine publications, may suggest that international spine research might be slower to adopt English as a universal language than the rest of the scientific community. This is merely a suggestion and requires further investigation to determine the cause of this discrepancy. These studies may seek to focus on the allocation of funds towards various scientific fields in these countries specifically. Furthermore, the observed trends in both all and spine-focused peer-reviewed publications stratified by language do indeed require further investigation to determine their causes.Clearly, this investigation has shown that there is a massive number of peer-reviewed spine publications that are inaccessible to English-only speaking spine scientists and surgeons. It also reveals that there are 758,532 peer-reviewed spine publications written in English that are not accessible to non-English speaking spine surgeons. If addressed, this could help disseminate peer-reviewed research both in the United States and across the globe which may increase the body of knowledge available to clinicians and possibly translate to improved patient outcomes.Compared to English (3.0%), non-English languages (2.8%) published a lower percentage of their total peer-reviewed publications on the spine since 1950. Individually however, the percent of total peer-reviewed publications that were published on spine in French (3.0%), Chinese (3.7%) and Japanese (3.7%) was greater than that of English. These languages were also found to contribute relatively more to spine than to all fields . While tIn 2008, the majority of scientific peer-reviewed publications coming out of Brazil were still in Portuguese. However, they were mostly covering topics of peripheral interests and had low impact factors and limited peer-review The aforementioned low representation of neurosurgical research in Latin America represents an example of ‘lost’ science, however, language barriers are bi-directional. While the ‘lost’ science in this case usually refers to the spine research that English-only speaking surgeons do not have access to, many non-English speaking spine surgeons may not have access to the vast volume of English-written spine research. This gap has much potential to represent the true ‘lost’ science in the world of spine surgery.rd most common inpatient surgical procedure in 2014, one can begin to understand the scale of impact that spine-related pathology has on patients both in the United States (US) and globally Spinal pathology is a global issue and therefore bridging scientific knowledge across countries and languages is crucial. Low back pain is the leading cause of disability worldwide 57% of peer-reviewed publications on the spine are from non-US countries and 13% of peer-reviewed publications on the spine have been published in non-English languages. The patients of spine surgeons are from diverse backgrounds and cultures. Recent work done by Jiang et al. and Hines et al. focused on quality improvement in the field of spinal surgery , 15. JiaWe believe significant efforts should be made to disseminate the ‘lost’ science. Current efforts are being made by some journals, like the Journal of International Medical Research, to provide a translation service for select languages. While these efforts are appreciated, greater efforts need to be made for all languages. Increasing the number of languages covered by these translation services would be an example of addressing this problem. Unfortunately, in an ever growing and maturing field, medical terminology can be difficult to translate. Efforts to create specific translational services for medical literature could be the key to producing reliable translations.This present study has limitations. For example, our method of retrieving peer-reviewed publications does not account for every published article. PubMed provides an excellent database of many of the top journals. Most of the ‘lost’ science is not appearing in these top journals and therefore, if anything, use of PubMed increases the likelihood of obtaining peer-reviewed publications from the United States and in English, while leaving those peer-reviewed publications from lesser-known journals and thus underestimates the degree of contributions from other countries and languages.Our data suggests that while English continues to contribute the most to the field of spinal surgery, the historic volume of peer-reviewed publications in other languages and different countries is massive and less accessible to American Spine Surgeons. Furthermore, the vast volume of English peer-reviewed spine publications are inaccessible to non-English speaking spine researchers and surgeons. Since 1988, there have been powerful surges in the number of written peer-reviewed publications on spine in the languages of English and Chinese and decreases in nearly all other investigated languages. This suggests that the languages of English and Chinese may one day be the most prevalent, creating a knowledge barrier between those who speak only one, or neither of those languages. As the field of spine research continues to expand globally, limiting the extent of these bi-directional ‘lost’ findings will be key in providing optimal care to our patients. Addressing this discrepancy will be vital to ensure that both National and International spine-related care improves such that patients across the world benefit from relevant research, no matter the language of origin.One or more authors declare potential competing financial interests or personal relationships as specified on required ICMJE-NASSJ Disclosure Forms.