Successful and minimally invasive extraction of a broken distal end of an intramedullary nail is challenging. This study introduces a simple and reproducible technique for the extraction of broken cannulated intramedullary nails using a novel minimally invasive broken nail extractor. Five amputated adult lower-leg specimens were used to create models of the broken distal end of the cannulated intramedullary nails remaining in the medullary cavity of the distal tibia. Two orthopedic resident physicians with experience in tibial intramedullary nail implantation were selected to blindly extract the broken intramedullary nail using the novel minimally invasive broken nail extractor. The extraction outcome was assessed. The broken nail extractor was applied to 3 patients with broken intramedullary nails remaining in the medullary cavity of the distal tibia. In the lower-leg specimens, the extraction success rate was 100%, the median number of extraction times was 1.9 (range 1–3.5), and the median duration of extraction was 38 s (range 20–52 s). All the broken intramedullary nails in the 3 patients were successfully extracted without complications related to the surgery. The study shows that our technique is simple, reproducible, and has a high extraction success rate, but more case applications are needed to verify its effect. Therefore, it is not uncommon for intramedullary nails to break in clinical practice. Broken nails remaining in the medullary cavity can be combined with bone nonunion or union. For postoperative nonunion of the fractured tibia and femur, closed replacement of the nail, including removal of the broken distal end of the nail, is becoming one of the preferred methods.,5 For postoperative bone union, removal of internal implants, including broken implants, is also in line with the customs of some ethnic groups. Multiple techniques have been used to extract a broken distal end of the nail.–12 Nevertheless, there is no guarantee that a particular extraction technique will be most effective for any given case. Therefore, it is incumbent on the surgeon to be familiar with a variety of intramedullary nail extraction techniques and have all potentially required equipment available. In this paper, we describe a simple reproducible extraction method for the broken distal end of cannulated nails using a novel minimally invasive broken nail extractor, which mainly reports trial results in cadaver specimens and their application in a few cases.Intramedullary nailing of long bone fractures is an accepted technique with the advantages of not disturbing the fracture hematoma and biomechanical superiority over plating. However, the incidence of nonunion or delayed union of long bone fractures after intramedullary nailing is 10% to 18%.The novel minimally invasive broken nail extractor for the broken distal end of cannulated intramedullary nails includes a guide wire and spear. The diameter of the guide wire is 2.8 mm. The spear consists of two Φ 1.0 mm Kirschner wires, with a barb with a diameter of 1 mm and a length of 2.5 mm on one side. The guide wire and spear were connected by welding. The diameter of the broken nail extractor at the barb can be adjusted according to the specific situation  age >18 years old. Exclusion criteria: previous tibial surgery; complicated with fracture of the tibia; 1.9 m < height <1.5 m; and structural abnormality of tibia caused by congenital development or acquired disease.This study including trial and clinical application was approved by the ethics committee of our hospital. Informed consent was obtained from all subjects. All experiments were performed in accordance with the relevant guidelines and regulations. From January 1, 2019, to May 30, 2021, seven adult calf specimens were collected and cryopreserved, of which 5 met the inclusion criteria and were used. The age of the adults from which the specimens were obtained ranged from 20 to 58 years, with an average of 41 years. After thawing the specimens to room temperature, the lower leg was placed in a supine position on the OT table. A skin incision was made from the lower pole of the patella to the tibial tuberosity. A midline patellar tendon splitting approach was performed, and the entry portal was made on a soft spot with a curved awl, followed by guide wire insertion into the distal tibia. Sequential reaming of the canal with a Φ 11 mm drill bit along the guide wire. A Φ 10 mm tibial intramedullary nail  with a broken front was placed distal to the tibial medullary cavity along the guide wire. The guide wire and intramedullary nail were pulled out, and the distal end of the broken nail was left in the distal medullary cavity of the tibia, which was confirmed by X-ray images , and the median extraction duration was 38 s (range 20–52 s). All broken cannulated intramedullary nails in the 3 cases were successfully extracted, the bone at the broken nail site was not fenestrated, and no adverse complications related to the surgery occurred (Fig. .5, and tA forty-eight-year-old male patient was admitted for the removal of all internal implants in his body. He had a closed tibial shaft fracture caused by a collision 15 years previously and was treated with closed reduction and intramedullary nail fixation. Delayed healing occurred after the surgery. The nail broke at the distal locking screw hole. The fracture healed after plaster fixation for 3 months. The internal implant was removed 3 years after the fracture, but the distal end of the broken intramedullary nail could not be removed using the hook extraction method and remained in the medullary cavity. Both surgeries were performed in another hospital. One year prior to admission, the patient underwent open reduction and internal fixation in our hospital due to a fracture of the right distal radius, which healed 2 months after the operation. His lower and upper limb function recovered well. It was known that the outer diameter of the broken nail was 10 mm, and the internal diameter was 3 mm from the medical documents of the hospital where the patient was treated. It can be seen from the preoperative X-ray film that the broken nail remaining in the intramedullary was hollow, and the internal diameter was larger than the isthmus of the medullary cavity Fig. a and b. –12 According to whether the bone at the broken nail site is fenestrated, these techniques can be divided into two categories: minimally invasive and fenestration extraction methods.Different techniques and methods have been described for extraction of the distal end of a broken cannulated intramedullary nail.The fenestration extraction method has a high success rate and basically avoids radiation exposure, but the disadvantage is that it creates relatively large area of surgical trauma.,7,12,13 The interference fit-guide wire method entails passing a ball-tipped guide wire and a nontipped guide wire or Kirschner wire through the nail canal, filling the canal as much as possible and extracting the broken nail using the resistance generated by the friction between the enlarged ball at the front of the wire and the canal wall.,7 The disadvantage of this method is that it is very difficult for the nontipped guide wire and the Kirschner wire to pass through the canal of the broken nail along with the ball-tipped wire. The hook extraction method involves hooking a guide wire through the broken nail canal and then extracting the broken nail. The disadvantage of the hook method is that it is very difficult for the hooked guide wire to pass through the broken nail canal. The typical case in the study was a patient that experienced failed hook extraction. Minimally invasive extraction methods require multiple X-ray fluoroscopies, which subject operators and patients to large doses of X-ray radiation, and their extraction success rate is not high.The interference fit guide-wire method and hook removal methods are the main invasive extraction methods.Our technique is simple to manufacture, and only one guide pin and one Kirschner wire must be welded. Its design is not only reasonable, but the success rate of extraction is also high. The tip of the extractor is relatively small and is located in the center of the front of the extractor so that it can easily enter the canal of the broken nail and guide the wide spear into the canal. The diameter of the spear at the barb could be reduced and expanded. After compression, the reduced diameter was ≤3 mm, allowing the body to pass smoothly through the canal of the broken nail. After passing through the canal, the body diameter increased to >3 mm, and the barb could easily hook the canal wall of the broken nail. The width of the barb is increased by nearly 2.0 mm after full expansion of the barb, not exceeding the thickness of the wall of the broken nail, so the barb does not hook the medullary cavity wall and get stuck. The connection between the barb and Kirschner wire provides appropriate resistance or supporting force to allow the broken nail to be extracted.The key points of operation are as follows: when it is expected that the broken nail extractor will encounter great resistance when passing through the medullary cavity, especially at the isthmus, a drill must be used to ream the medullary cavity. Second, the diameter of the broken nail extractor at the barb should be adjusted according to the internal diameter of the broken nail to be consistent with or slightly larger than the internal diameter of the broken nail. Otherwise, if the diameter is too large, it is not easy to enter the canal of the broken nail tube; if the diameter is too small, it is not easy to hook the tube wall.There was no comparison with other methods; only a few cases were used in this study. Therefore, comparisons with other methods and more case applications are needed to verify its effect.Our technique is a simple reproducible alternative that has a high extraction success rate, but more case applications are needed to verify its effect.Conceptualization: Zihong Zhou, Yan Jiang, Changbao Wei.Data curation: Beichen Dai, Guoshu Mao.Methodology: Yu Liu.Resources: Zihong Zhou, Guoshu Mao.Supervision: Yan Jiang.Writing – review & editing: Chnagbao Wei.Changbao Wei: 0000-0002-1381-0710


Young children are frequently exposed to antibiotics, with the potential for collateral consequences to the gut microbiome. The impact of antibiotic exposures to off-target microbes  and antibiotic resistance genes (ARGs) is poorly understood.We used metagenomic sequencing data from paired stool samples collected prior to antibiotic exposure and at 1 year from over 200 infants and a difference-in-differences approach to assess the relationship between subsequent exposures and the abundance or compositional diversity of microbes and ARGs while adjusting for covariates.Bacteroides vulgatus relative abundance increased by 1.72%  while Bacteroides fragilis decreased by 1.56% . Bifidobacterium species also exhibited opposing trends. ARGs associated with exposure included class A beta-lactamase gene CfxA6. Among infants attending day care, Escherichia coli and ARG abundance were both positively associated with antibiotic use.By 1 year, the abundance of multiple species and ARGs differed by antibiotic exposure. Compared to infants never exposed to antibiotics, Novel findings, including the importance of day care attendance, were identified through considering microbiome data at baseline and post-intervention. Thus, our study design and approach have important implications for future studies evaluating the unintended impacts of antibiotics.The impact of antibiotic exposure to off-target microbes and antibiotic resistance genes in the gut is poorly defined.We quantified these impacts in two cohort studies using a difference-in-differences approach. Novel to microbiome studies, we used pre/post-antibiotic data to emulate a randomized controlled trial.Compared to infants unexposed to antibiotics between baseline and 1 year, the relative abundance of multiple off-target species and antibiotic resistance genes was altered.Escherichia coli and antibiotic resistance genes; a novel finding warranting further investigation.Infants who attended day care and were exposed to antibiotics within the first year had a higher abundance of  This is a particular concern in the human gut, a known reservoir for antimicrobial resistance genes (ARGs).20 Indeed, multiple studies have found that antibiotic exposures lead to the proliferation of ARGs that confer resistance to the antibiotic prescribed and to other antibiotics.24Infants and young children are exposed to more antibiotics than any other age group25 leading to further risk of antibiotic-resistant microbial infections. Integrated strategies that consider the microbiome are increasingly becoming useful for improving the surveillance of ARGs and providing clinical recommendations to prevent antimicrobial-resistant infections.26 Commensal bacteria can harbor ARGs and carriage prevalence of potentially pathogenic microbes can lead to antimicrobial-resistant infections. Thus, there is an urgent need to conduct epidemiologic studies and build quantitative models to understand how antibiotics affect off-target microbes, antimicrobial resistance, and unintended health outcomes.Mitigation of antimicrobial resistance is a global health priority as the incidence of infections requiring second or third-line broad-spectrum antibiotics for treatment is on the rise,27 The advantage of this design is that it uses baseline information  to account for intra-subject variation over time and a comparison group to assess differences among those exposed and unexposed to an intervention. This approach is equivalent to assessing the interaction effect between the exposed group and the post-intervention time point.28 As antibiotics are often prescribed for respiratory illnesses and ear infections unnecessarily,29 this study offers insight that can support antibiotic stewardship practices in light of the effect of antibiotics on commensal gut microbes and ARGs.The goal of the current study was to quantify the population-level effects of antibiotics on the abundance and diversity of off-target microbes and ARGs. Specifically, we use pre/post-antibiotic data to estimate average population-level changes to individual microbes, ARGs, and compositional diversity metrics emulating a randomized controlled trial. This difference-in-differences approach is frequently used in health services and policy research but has not been previously applied to microbiome studies.32 but, in brief, enrollment began in 2009 to study the effects of environmental exposures on pregnant women and young children. Extensive data are available for the first year of life and include delivery and pediatric medical records, as well as interview data for 4, 8, and 12 months post-delivery. Stool samples have been collected and undergone shotgun sequencing from a subset of children throughout the first year of life but predominantly at the 6-week and 1-year timepoints. Pregnant women and their children were recruited using the NHBCS’s current Dartmouth Institutional Review Board-approved procedures by the Center for the Protection of Human Subjects.The New Hampshire Birth Cohort Study (NHBCS) is an ongoing prospective cohort study of over 2250 pregnant women and their young children from New Hampshire and Vermont. A detailed description of the cohort has been published,33 We used data from infants in a DIABIMMUNE sub-study that aimed to examine the role antibiotics play in microbiome development over the first 3 years of life.23 The sub-study included 39 infants from Finland having either 0 or at least 9 antibiotic exposures within their first 3 years of life. Children in this cohort had stool samples collected throughout their early life starting at about 2 months of age. We accessed quality-controlled shotgun sequencing FASTQ files and covariate data through their publicly available website.34The DIABIMMUNE Study is a cohort of infants in Finland, Estonia, and Russia focused on the hygiene or microbiota hypothesis and its potential role in the development of autoimmune diseases.We were interested in systemic antibiotic exposures between the 6-week and 1-year timepoints (to match available stool samples) with a goal of studying both exposure (yes/no) and the frequency of antibiotic courses given to all infants. A unique advantage of the NHBCS is that antibiotic prescriptions, including indication, are captured in both medical records and caregiver questionnaires administered at 4, 8, and 12 months of age.As outlined in Supplementary Fig. 33 Infants from the DIABIMMUNE Study were added to NHBCS sub-cohorts to make combined cohorts, referred to respectively as the Antibiotic Exposure and Antibiotic Frequency Cohorts  v3.1.1.39 In CARD, model names are sometimes annotated by microbes that they have been identified in, but this may not necessarily reflect the microbial origin. Information on the ARGs profiled is available in Supplementary Table Details on stool collection and metagenomic DNA shotgun sequencing have previously been described for the NHBCS cohort40 with additional details on overall ARG abundance and correlation analysis in the Supplementary Notes.All statistical analyses were performed using R version 3.6.0,27 Assumptions required for the difference-in-differences approach28 were assessed prior to use.The difference-in-differences approach is frequently used in health services and policy research to estimate the effect of change due to an intervention or policy on a population when a randomized controlled trial is not possible or ethical.41 Our general formula was:The difference-in-difference estimate was performed using Microbiome Multivariable Associations with Linear Models (MaAsLin2).Where abundance is the relative abundance of the microbe or ARG in each sample, sample age is the time in days of the sample collection, antibiotic exposure is a dichotomous indicator of if the infant was exposed or not exposed to an antibiotic ever, and sampling interval is a binary variable used to denote that the measurement was from baseline (~ 6 weeks or 2 months) or 1-year. Antibiotic exposure × sampling interval represents the difference-in-difference estimate or interaction between exposure and time interval. We considered intercept random effects at the infant level (1|infant).23We used rigorous classification rules (Supplementary Notes) to retrospectively assess antibiotic exposure and frequency in 238 infants in the NHBCS that had shotgun sequencing data from stool samples collected at both ~6-week and ~1-year timepoints . Infants from the DIABIMMUNE Study were more likely than infants from at least one NHBCS sub-cohort to be vaginally delivered . The average baseline age and days breastfeeding of infants from the DIABIMMUNE Study was approximately 20 days greater than that of infants from the NHBCS .Comparisons between the DIABIMMUNE and NHBCS Antibiotic Exposure and Antibiotic Frequency sub-cohorts indicated that the proportions of infants that were female and that were born full-term were similar  more than it would have if the infant was never exposed to an antibiotic, while the relative abundance of Actinomyces odontolyticus decreased by 0.008% . Relative abundance changes based on antibiotic exposure went in opposing directions for Bacteroides and Bifidobacterium species. While B. vulgatus abundance increased, Bacteroides fragilis decreased by 1.42% . Similarly, Bifidobacterium bifidum relative abundance increased 1.41%  more than it would have if the infant was never exposed, but Bifidobacterium longum and Bifidobacterium breve decreased by 1.56%  and 1.14%  respectively.Since all antibiotic exposures were for non-gut-associated infections, we classified all microbes as off-target. Looking specifically at antibiotic-exposed versus unexposed infants from the NHBCS and the DIABIMMUNE Studies Fig. , we foun44 and is time variant (see Supplementary Notes), we stratified NHBCS infants in the Antibiotic Exposure Cohort by day care attendance by 1 year to attempt to separate the effect of day care attendance and antibiotic exposure on off-target microbes   more than if the infant was not exposed to antibiotics , tetM (ARO: 3000186), and mdtO (ARO: 3003549)  Fig. .Fig. 3VoTo investigate this further, we looked at overall ARG abundance in the same infants  among infants unexposed to antibiotics and 60 pairs and 19 clusters for exposed infants with 49 pairwise associations overlapping  testing. Across the 41 species and 55 ARGs analyzed, 111 pairs and 47 clusters were identified as having a statistically significant correlation  antibiotic exposures prescribed for otitis media. This largely correlates with other studies from similar demographic groups that have estimated approximately 30–40% of infants are exposed to antibiotics in the first year.52 and (2) inhibiting pathogen colonization directly through nutrient competition and bacteria-bacteria attacks53 as well as indirectly by stimulating the development of cells necessary for innate and adaptive immunity.54 Thus, decreased presence or abundance due to antibiotic exposure is a major concern. However, previous studies inconsistently identify particular commensal microbial abundances that have increased or decreased as a result of antibiotic exposure and often only profile results at the genus level.55 While the majority of our results did not indicate statistically significant differences between antibiotic-exposed and unexposed infants, our results justified the need to evaluate differences below the genus level especially for Bifidobacterium and Bacteroides.Commensal microbes have many roles in the infant gut microbiome that include: (1) degrading polysaccharides into useable sugars and short-chain fatty acids for other gut microbesBifidobacterium species exhibited conflicting trends in our study. The relative abundance of two species, B. longum and B. breve, consistently decreased in the antibiotic-exposed population. However, B. bifidum increased in relative abundance after antibiotic exposure. This trend suggests that antibiotic exposure may lead to long-term selection changes to favor certain species of Bifidobacterium. Limited studies have specifically assessed Bifidobacterium species,55 but a prior study in 1.5-year-old children found that B. bifidum concentration decreased by 23% in amoxicillin exposed children compared to 54.5% in unexposed children while B. longum concentration remained consistent immediately following exposure.56 Differences identified between studies may be a result of differences in population demographics including the age of the children as well as the time period post antibiotic exposure.B. vulgatus relative abundance increased in antibiotic-exposed children but B. fragilis decreased. These results are interesting in context to the DIABIMMUNE Study that identified B. fragilis as a “single-colonization species” and B. vulgatus as a “multiple-colonization species” based on the dominance of one vs. multiple strains across time.23 Species with multiple strains in an environment are thought to contribute to a more resilient microbiome.58 While we did not assess strain diversity and at least one previous study suggests these species may have a similar sensitivity to amoxicillin-based antibiotics,59 our results underscore the need to consider differential sensitivity to antibiotics as a result of strain-level diversity, differences in biogeographical niches,60 and variation in ARG carriage by species. Regarding ARG carriage, the CARD continually tracks the prevalence of antibiotic resistance phenotypic profiles in reference sequences for many non-pathogenic microbes. According to the CARD prevalence 3.0.9 update, there is wide variability in ARG phenotypes between commensals from the same and different genera.39 These data, in combination with the results from this study and others assessing antimicrobial susceptibility in bacteria often considered off-target,62 provide further evidence that intra- and inter-species variation is important to consider.We consistently identified that 67 but have been conducted in predominantly preterm infants22 or contained relatively small cohorts (<30 infants) of antibiotic-exposed infants.66 We found two distinct patterns in our study, but, regardless of antibiotic exposure, found that E. coli was the microbe most frequently correlated with ARGs  as ARG markers of interest. CfxA genes work via antibiotic inactivation39 and have been identified in a wide range of microbes from Bacillota  and Bacteroidota (Bacteroidetes) including Bacteroides, Prevotella, and Capnocytophaga with point mutations differing between CfxA2 and CfxA6.71 The DIABIMMUNE Study found the CfxA6 gene marker persisted in children long after antibiotic exposure.23 Although some of these infants were included in our study, we independently found that the gene increased in abundance in infants in the NHBCS only -llla to be increased among infants exposed to a beta-lactam inhibitor compared to infants not exposed to any antibiotic. For CfxA2, they found that it was also increased among infants given another antibiotic compared to no antibiotic exposure. Although they did not have resistome measurements taken before antibiotic exposures to establish baseline ARG abundances, the results of our study aligned with these results and those presented previously in our cohort.35 In addition, a study of healthy adults exposed to a 7-day treatment of cefprozil found specific point mutations in CfxA6 were enriched in multiple participants68 and another study identified CfxA6 to be an important discriminator of gestational age.21 Given all this data, further detailed investigations of the CfxA6 gene at the sequence level are warranted.In our Antibiotic Exposure Cohort, only ARO: 3003730 nts Fig. . Accordised Fig. , this prnly Fig. . The mosE. coli relative abundance increased in antibiotic-exposed infants . We also used exposure data with more precision on a smaller sample group of infants via a medical record review to assess timing and type of antibiotic exposure. Although statistical tools have used mixed-effects models to assess microbiome composition longitudinally,Our results support the notion that microbiota and the resistome should be considered when weighing the costs and benefits of antibiotic interventions. Moreover, we apply an established framework used to emulate a randomized controlled trial to the microbiome space. This enabled quantification of the magnitude of the population-level effects of antibiotic exposure in the context of other pressures impacting the developing microbiome in early life. We imagine that this novel application can be used to evaluate the potential impact of new or current antibiotic prescription practices on gut microbiota and residual impacts on ARGs.Supplementary Figures and NotesSupplementary Tables


The results of ANN models showed a better prediction of the compressive strength with regression (R) equal to 0.928 and 0.986. The optimum mixture includes CKD 10–20% and FA 0–30%. Predicting the compressive strength of green concrete is a non-destructive approach that has sustainable returns including preservation of natural resources, reduction of greenhouse gas emissions, cost, time, and waste to landfill as well as saving energy.Integrating artificial intelligence and green concrete in the construction industry is a challenge that can help to move towards sustainable construction. Therefore, this research aims to predict the compressive strength of green concrete that includes a ratio of cement kiln dust (CKD) and fly ash (FA), then recommend the optimum sustainable mixture design. The artificial neural network (ANN) and multiple linear regression techniques are used to build prediction models and statistics using MATLAB and IBM SPSS software. The input parameters are based on 156 data points of concrete components and compressive strengths that are collected from the literature. The developed models have been trained, validated, and tested for each technique. TOPSIS method is used to assign the optimum mixture design according to three sustainable criteria: compressive strength, carbon dioxide (CO Green building is classified under three criteria which are energy, material, and resource conservation. Therefore, a sustainable design is essential and lies under the green building criteria which are related to the material that is used in the design. Eventually, the use of industrial waste material could be the potential solution for energy and material issues. Industrial residues can be utilized as a part of concrete innovations to make eco-friendly concrete.Construction is one of the main processes of evolution that never stops. Sustainable construction has been a topic discussed in the last century to minimize the negative effect of construction on the environment such as the depletion of natural resources and waste or reuse of any waste material that comes from different industries2 and greenhouse gas due to the combustion of fossil fuels for heating the cement-making process, and the thermal decomposition of calcium carbonate for producing cement clinker process. About 88% of the concrete mix emissions are related to cement. Therefore, there is a direct relationship between the CO2 emission from concrete production and the cement content used in it. Moreover, cement industry emits a considerable amount of air-pollutant such as Dust, sulfur dioxide (SO2), and nitrous oxides (NOx). On the other hand, cement production is considered as one of the most energy intensive manufacturing process of all industries2.Concrete has been one of the main materials that are used in almost all structures. The concrete industry causes some environmental problems such as global warming, natural resource depletion, air pollution, and waste. Cement, which is the major component of concrete, is a main producer of CO2 emissions and air pollution from cement manufacturing. In addition, wastes can be replaced by aggregate, called alternative aggregates, that leads to conserving more natural resources3. However, estimating the properties of the produced green concrete is a big challenge because the mechanical properties and durability of concrete is very important. Determining these properties only through laboratory testing consumes a lot of energy and materials besides those tests are destructive approach. Therefore, artificial neural network (ANN) can help to predict the concrete properties in nondestructive approach with saving in energy consumption, materials, and time4.Consequently, green concrete was used as an eco-friendly concrete. Green concrete is made from waste materials that are produced from construction waste or other industrial wastes. Supplementary cementitious materials (SCM) are those wastes which replacing a portion of cement in the concrete mixture. Hence, reducing the quantities of cement can reduce CO5. Cement kiln dust (CKD) is a by-product waste material resulting from cement manufacturing. Fly ash (FA) is a fine powder that is generated from gases produced by coal-fired electric power generation, and usually discarded in landfills.Solid waste management has a significant importance because there is an increase of the generated quantities of by-products. The disposal of industrial by-products is a big concern for industries due to the increasing amount of by-product waste generated and increasing costs of landfills. There are various waste materials and by-products that can be used as replacement of cement in the concrete mixture, such as cement kiln dust, blast furnace slag, fly ash, silica fume, recycled glass, date palm ash, granite waste, and others2) emission, and cost. The methodology of this study can be summarized in the following steps:Reviewing of the different research that used CKD and FA as waste materials in green concrete mixtures as well as the different artificial intelligent techniques that are used to predict the compressive strength of concrete.Establishing the model database by gathering the necessary information about the components and compressive strength of the concrete mixtures that contain CKD and FA from previous research.Applying statistical analysis for the collected data using IBM SPSS software.Developing the prediction models using two methods: Artificial Neural Networks (ANN) and multiple linear regression (MLR) using MATLAB and IBM SPSS software. The processes include models training, validation, testing, comparing and analysis of results.Performing permutation analysis to get the correlations and importance of input variables of the resulting compressive strength.2) emission, and cost criteria using TOPSIS method as a multicriteria decision making (MCDM) technique.Assigning the recommended optimum green concrete mixture design based on the compressive strength (CS), carbon dioxide (COThis research aims to predict the compressive strength of green concrete that includes a ratio of cement kiln dust (CKD) and fly ash (FA), as industrial by-products, using two methods: artificial neural network (ANN) and multiple linear regression (MLR). In addition, assign the recommended optimum green concrete mixture design based on three sustainable criteria: compressive strength (CS), carbon dioxide  in terms of weights. Prediction models are created using two techniques: artificial neural networks (ANN) and multiple linear regression (MLR). Permutation and statistical analysis are performed to evaluate the importance of the input variables on the predicted compressive strength as well as the accuracy of the developed models. The recommended mixture design is assigned after optimization based on technical, environmental, and economic criteria. The benefits of this approach may include the preservation of natural resources, reduction of greenhouse gasses emissions, cost, time, and waste to landfill as well as saving energy.6. Therefore, several research investigated the properties of green concrete that uses industrial wastes and byproducts. For example, cement kiln dust18, fly ash22, blast furnace slag26, silica fume29, recycled glass31, granite waste33, and Date Palm Ash36.The increasing of green concrete research is due to environmental awareness, economic benefits, and laws16 used the cement kiln dust CKD that helped filling the micro voids in mixture with proportions of 1, 2, 3, 4 and 5% replacement rations of cement by weight. It improved the mechanical properties such as the compressive strength, direct tensile strength and flexural strength16. Omrani and Modarres17 studied the effect of CKD and coal waste ash in the emulsified cold recycled mixture. It is concluded that there were high economic and environmental benefit by substituting 1 and 2% of cement content17. Yoobanpot et al.18 used CKD and the fly ash FA that helped changing the structure of the mortar by adding 10% of CKD & FA as replacement to the same portion of the ordinary portland cement content. The structure was enhanced and densified as the compressive strength developed with time and the voids in the mortar structure were reduced which made it stronger18. As mentioned by Abdel-Gawwad et al.7 used of CKD and FA helped improving the production of the pozzolan materials as the different reactivity and whiteness were investigated. First materials were treated at 1000 degree then they were used in ratios which affect the strength directly as one of the samples which had fly ash cement kiln dust 80/20 (FA/CKD) produced about 89% whiteness and 100% amorphous content. They replaced 30% by weight of white Portland cement. It resulted in improving the compressive strength after 28 days and enhanced the whiteness7.Kadhim et al.8, the effect of replacing portions of ordinary Portland cement and sulphate resisting Portland cement in concrete mix using certain percentage of cement kiln dust was similar, the substitution of 10% and 20% by weight cement kiln dust as replacement of cement. Another experiment added 10% kiln dust to cement. And finally, another experiment added 20% CKD along with superplasticizer additives. The results showed that the increase of cement kiln dust in the mix and accordingly the decrease in water/cement ratio, the two samples with 10% and 20% additional CKD had increased the compressive strength unlike the replacement samples which showed a decrease in the compressive strength as CKD increased8. Al-Rezaiqi et al.10 studied the effect of replacing cement by cement kiln dust (CKD) and burnt clay on the concrete properties. It was concluded that replacing cement up to 20% CKD had a non-significant effect on concrete strength and durability10.According to Abdulabbas38. Teixeira et al. found that incorporating by-product waste of power/heat production sectors as fly ashes in concrete as cement replacement can improve the environmental performance of the concrete39. Bagheri et al.40 used different amounts of CKD and FA as a replacement of cement and used Taguchi method to determine the optimal mixing design considering the environmental and economic parameters.Strength, segregation, and ease of pumping of concrete can be improved using FA. Using fly ash (FA) from coal-fired power plants has two major benefits. The first is solving the waste problems; the second is reducing overall energy use. The use of fly ash as SCM in various concrete applications has been investigated by many researchers. It can be used as a cement replacement in concrete mix because it contains silica. Fly ash increases concrete strength, improves both sulfate resistance and workability, and decreases both permeability and water ratio required. The utilization of different types of fly ash for artificial sintered aggregate in order to produce lightweight high strength concrete is studied44 and regression analysis46. Khademi et al.47 predicted compressive strength of recycled aggregate concrete at 28 days using three different models which are the (ANFIS) adaptive neuro-fuzzy inference system, (ANN) Artificial neural network, (MLR) Multiple linear regression. It was found that ANN and ANFIS models were better and more accurate than the MLR model and proved that the effect of using the non-dimensional parameters increased the performance of the models47. Verma and Kumar4, used ANN to forecast the compressive strength of concrete mix including two different cement types: Sulphate resisting Portland cement and Portland cement, and two different types of aggregates: manufactured sand and natural sand, for four different water-cement (w/c) ratios. The predicted strength results were compared to the laboratory results. It was found that the optimum results were obtained for Sulphate resisting Portland cement with manufactured sand4.Recently, many artificial intelligence systems have been widely applied to predict the concrete strength such as neural networks44, proposed a neural network model that to forecast the compressive strength of rubber concrete. Duan et al.48 developed an ANN model that can forecast the compressive strength of concrete that includes recycled aggregate instead of natural aggregate. Shahmansouri et al.49 constructed an ANN model to predict the compressive strength for geopolymer concrete containing ground granulated blast-furnace slag, silica fume and natural zeolite. The model is verified using different multiple accuracy metrics such as including the mean squared error and correlation coefficient49. Chou et al.50 proposed an ANN model that can predict the compressive strength of high-performance concrete.Bang Ly et al.54. Moreover, multi expression programming, firefly algorithm, multilayer perceptron neural networks, adaptive neural fuzzy detection systems, genetic programming, random forest regression, individual and ensemble machine learning approaches are utilized to forecast the compressive strength of concrete, carbon fiber-reinforced polymer confined concrete, lightweight foamed concrete, silica fume concrete, and high-performance concrete including waste materials59.On the other hand, several researchers have worked on developing prediction models using several artificial intelligence techniques to predict the compressive strength of concrete and showed high accuracy towards the prediction of outcomes. For example, using machine learning algorithms of gene expression programming, artificial neural network, ensemble random, and support vector machine to develop predictive models for compressive strength of concrete containing fly ash, lightweight foamed concrete, high strength concrete, self-compacting concrete, and density3) of concrete to improve the usability of the model.All prediction models revealed high-accuracy predictions and consistent behavior. It was also concluded that predicting concrete strength shall be conducted using ANN or other machine learning techniques. Finally, an artificial neural network (ANN) is one of the capable techniques that can predict concrete compressive strength, therefore, it is used by several researchers for that objective. Based on the reviewed literature, most studies developed their predictions to the 28-days compressive strength of concrete. However, the research gap can be defined as there is a lack of studies that predict the strength of green concrete containing CDK or CDK with FA as cement replacement waste materials. Furthermore, most studies used input parameters (W/C ratio or % fine aggregate to coarse aggregate) in their models as ratios. In this study, the input variables are inserted in terms of the weight  that fits a straight line that minimizes the discrepancies between predicted and actual output values. It can estimate the level of correlation between on dependent variable (compressive strength) from independent variables (input mixture components). It is relatively simple and provides an easy-to-interpret mathematical formula that can generate predictions and compare them to the results of the ANN models. MATLAB and IBM SPSS software have been used to apply ANN and MLR prediction models due to their user friendliness and power.In this study, two prediction tools are used separately—to prepare the prediction model of the compressive strength of green concrete to compare their results. Firstly, Artificial neural networks (ANN) technique is selected because it is a computing system that simulates the function of the neurons in the human brain. It works as a self-learning system that helps it to solve complex problems. Just like the human brain, Artificial neural network, contains numerous artificial neurons which are the processing units that is being joined by links, these are connected in the form of a web which process the input and the output informationFor each tool (ANN and MLR), two prediction models are developed to predict the compressive strength (CS) of green concrete mixture after 28 days of pouring. The first model is developed for the concrete mixture that includes CKD only as partial replacement. While the second model is developed for the concrete mixture that includes CKD and FA as partial replacement. Both ANN models are trained with different layers to get the optimum number of hidden layers that produce the best regression graphs and prediction results to be used in the final models. The output for each model is similar, which is prediction of the concrete compressive strength. Model (1) includes six inputs representing the components of the green concrete mix including fine aggregate, coarse aggregate, water, cement, CKD, and superplasticizer. While model (2) includes seven inputs representing the components of the green concrete mix by adding FA to the six components of model (1) mixture. Training, testing, and validation samples for each model include 70%, 15%, and 15% of the model data respectively. Figure The ANN is trained to recognize data in patterns. During this process the artificial neural network compares the actual output with the estimated then it adjusts network weights by the difference between both outputs using the backpropagation, after the adjustment, the network produces the lowest error that could occur. Regression graphs for both ANN models are generated and presented in Fig. The models that were built using MLR have similar inputs and outputs to the ANN models. Model (1) has six inputs and one output; Model (2) has seven inputs and one output. The model selection method for MLR is Forward Stepwise. Figure Figure Seven parameters are employed as inputs: fine aggregate, coarse aggregate, water, cement, cement kiln dust (CKD), fly ash (FA), and superplasticizers (SP). Permutation analysis is performed to determine the most influential parameters affecting the compressive strength of concrete. Table In addition, ANN models are created using IBM SPSS to validate the results and get the contribution of each variable in the predicted compressive strength. Sum of squares error of are 1.847 and 1.0 (for training), and 3.228 and 0.194 (for testing) for models 1 and 2 respectively. The relative errors are 0.059 and 0.047 (for training), and 0.193 and 0.028 (for testing). The importance of each input parameter to the construction of ANN models is presented in Table 2) emissions. The quantity of CO2 emissions from cement manufacturing is 852 kg/ton70. Finally, the cost of cement, fine aggregate, and coarse aggregate can reflect the economic factor. The cost of these components is collected from the local market. It is assumed that waste materials have zero cost. Therefore, the optimization of the mixture design is based on three sustainable criteria: compressive strength, CO2, and cost. Table Selecting the optimum percentage of CKD in the mixture and consequently finding the optimum mixture design is a sustainable challenge to produce green concrete. Therefore, the optimization process can be achieved by optimizing technical, environmental, and economic factors to get the recommended sustainable mixture. Maximizing the compressive strength of the mixture reflects the technical factor. Minimizing the cement contents can reflect the environmental factor because cement is the responsible of the most carbon dioxide  is assigned to each alternative mixture within a range between 0 and 1. The final order is obtained sorting the set of alternatives decreasingly in terms of Ri+71. The following steps of TOPSIS method are followed for an alternative i under evaluation criterion j and its weight wj:ij and rij are evaluation and normalized evaluation matrix R (respectively)Technique for Order Preference by Similarity to the Ideal Solution (TOPSIS) is used as one of the popular MCDM methods. In TOPSIS, the rank of alternative mixtures is calculated according to their separation from an ideal point. The best measure is that has the shortest distance to the positive ideal solution and the longest distance from the negative ideal solution. The distance Ri2 and cos to notice and compare results. To assign weights for the three criteria (CS:CO2:Cost), four scenarios are assumed as presented in Fig. 2 using 25:50:25 ratios respectively, and the fourth scenario maximizes the weight of the cost using 25:25:50 ratios respectively.Bh actual and predicted compressive strengths and considered iividually with COThe optimum mixtures are listed in Table Green concrete is highly recommended to be used in the construction industry because it has many environmental, technical, and economic advantages. Green concrete can be produced by re-using different wastes in concrete mixtures as cement replacement, resulting in reduction of its negative environmental impacts in addition to increasing its compressive strength. In order to get results of green concrete compressive strength, laboratory works are needed which consumes materials, equipment as well as time and cost. Therefore, the artificial neural networks (ANN) technique and multiple linear regression (MLR) are used to develop models that can predict the compressive strength of concrete including cement kiln dust and fly ash. After that, TOPSIS method is used to get the optimum sustainable mixture design. The developed prediction model is based on the data collected from literature including 156 data points. MATLAB and IBM SPSS software are used to create models and statistical analysis.2) emission, and cost. It is found that the optimum mixture includes CKD 10–20% and FA 0–30%.Using artificial inelegance applications in construction industry can open the door for development of more innovative approaches that contribute to sustainable construction. Most studies have emphasized increasing the number of samples to enhance ANN training and reduce prediction error. Consequently, samples were developed during training and more than one training model was conducted. Therefore, artificial neural networks can be taught in order to obtain the lowest percentage of error prediction based on trial and error. Training, validation, and testing samples were developed in two models. The first model for green concrete contains CKD. The second model for green concrete contains CKD and FA. It is concluded that ANN model has accuracy better than MLR model. The results of ANN models showed a better prediction of the compressive strength of green concrete with regression (R) equal to 0.928 and 0.986. Finally, TOPSIS method is used to select the optimum mixture design according to three sustainable criteria: compressive strength, carbon dioxide  in concrete mix instead of disposal to landfill, and saving energy by replacing cement with waste materials.The proposed approach may reflect several advantages including: reduction in COThe future trends in green concrete applications are various and more research have to encourage its usage. For future research, it is recommended to develop prediction models that focus on other properties of green concrete such as flexural strength, splitting tensile strength, density, workability, resistance to chloride penetration, resistance to sulphate attack penetration, or strength under elevated temperatures. On the other side, prediction models for different concrete mixtures including several wastes such as construction and demolition waste, glass waste, recycled tire rubbers, waste silica, spent foundry sand, steel slag, granulated blast furnace slag, copper slag, marble waste, or quarry dust can be investigated.


Oryza sativa were identified, and the structure of the enzyme at the protein level was studied. The genes controlling PHO2 were found to be more conserved than those controlling PHO1; the variations were mainly due to the variable sequence and length of introns. Cis-regulatory elements in the promoter region of both genes were identified, and the expression pattern was analyzed. The real-time quantitative polymerase chain reaction indicated that PHO2 was expressed in all tissues with a uniform pattern of transcripts, and the expression pattern of PHO1 indicates that it probably contributes to the starch biosynthesis during seed development in Zea mays. Under abscisic acid (ABA) treatment, PHO1 was found to be downregulated in Arabidopsis and Hordeum vulgare. However, we found that ABA could up-regulate the expression of both PHO1 and PHO2 within 12 h in Zea mays. In all monocots and dicots, the 3D structures were highly similar, and the ligand-binding sites were common yet fluctuating in the position of aa residues.Starch phosphorylase (PHO) is a multimeric enzyme with two distinct isoforms: plastidial starch phosphorylase (PHO1) and cytosolic starch phosphorylase (PHO2). PHO1 specifically resides in the plastid, while PHO2 is found in the cytosol. Both play a critical role in the synthesis and degradation of starch. This study aimed to report the detailed structure, function, and evolution of genes encoding PHO1 and PHO2 and their protein ligand-binding sites in eight monocots and four dicots. “True” orthologs of PHO1 and PHO2 of  Zea mays) is one of the three major cereal crops globally and the largest in food crops, with a yield second to rice (Oryza sativa). The major part of the yield is known as starch, which is the most important form of reserve polysaccharide synthesized in cellular organelles in plants called plastids [Maize  to growing α-1-4 linked glucan chain in a reversible reaction that depends on the available substrate level . In planZea mays , Oryza sa sativa  Triticum vulgare , and Soluberosum . PHO2 cauberosum . In addiuberosum .Ipomoea batatas [Solanum tuberosum maintains its intact structure in young tubers, however steadily degrades into smaller peptides as the tubers become mature [Vigna radiata. Interestingly, both forms were identified to make active catalytic complexes [Oryza sativa [Zea mays [Hordeum vulgare [Triticum aestivum [Hordeum vulgare PHO1 crystal structure has been characterized [These two enzymes are highly similar to each other, however they differ in the presence of transit peptides in the N-terminal and an extra stretch of 78–82 amino acid (aa) residues (L80 domain) in the middle region of PHO1. The presence of this extra peptide can be responsible for varied biochemical activities . Previoue mature . Both thomplexes . In conta sativa ,25, Zea Zea mays , Hordeum vulgare , and Triaestivum  is not daestivum ,27. The aestivum . Quantitcterized .PHO may play a role under different stresses. However, the regulation pattern found variables among the main cereal crops, especially in Arabidopsis thaliana, where PHO1 seemed to play a role in the tolerance of abiotic stress rather than the degradation of starch [PHO1 of Hordeum vulgare suggested no effect of ABA on the expression of PHO1, although there was up-regulation of PHO2 [Arabidopsis thaliana significant down-regulation for both isoforms were detected. Considerable information about PHO and its gene is available. However, detailed information about gene diversity, structure variation, function, evolution, and PHO responding to phytohormones is unclear in some important crops, including Zea mays. In recent years, significant progress has been made by scientists in sequencing plant genomes. The availability of genome data is essential to answer the biological questions through comparative analysis [Oryza sativa as a reference (as these are well characterized and closely related to Zea mays) to identify and characterize its orthologs from eight important monocots and four important dicots. The obtained results are presented in this communication, including “true” orthologs of PHO1 and PHO2 genes, evolution of gene structure for both isoforms across mentioned species, synteny and collinearity analysis, identification of conserved and variable domains with subtle differences between both isoforms and among the monocots and dicots, promotor analysis, and expression analysis with the effect of ABA treatment on the expression of both isoforms of PHO in Zea mays.Several reports on microarray based analysis combined with promoter sequences indicated that f starch . A study of PHO2 . In contanalysis . TherefoO. sativa were identified from the 12 different species using the criteria mentioned in the Materials and Methods section. Thus, the genome, coding DNA sequence (CDS), and cDNA of PHO1 and PHO2 from the mentioned orthologs were obtained and are presented in O. sativa (used as reference) ranged from 78.1% to 81.7% in monocots and 42.2% to 65.0% in dicots. Likewise, the similarity of cDNA of PHO2 ranged from 80.4% to 81.7% in monocots and 62.9% to 65.9% in dicots. The CDS similarity of PHO1 ranged from 90.4% to 91.9% in monocots and 80.5% to 81.6% in dicots. Likewise, the CDS similarity of PHO2 ranged from 86.0% to 93.5% in monocots and 82.8% to 85.1% in dicots. The similarity index of gene sequences was low compared with that of cDNA and CDS; it ranged from 49.2% to 63.0% in monocots and 45.9% to 46.3% in dicots; for PHO2 it ranged from 36.7% to 62.4% in monocots and 11.8% to 47.6% in dicots.The “true” orthologs of the PHO1 and the PHO2-encoding genes of PHO1) and PHO2 (PHO2) from different species were compared using O. sativa as a reference. The length of the genes was a major difference, which ranged from 2.92 Kb to 9.02 Kb in PHO1 and 5.24 Kb to 34.54 Kb in PHO2. PHO1 was the longest for Z. mays and smallest for S. tuberosum  and PHO2 of P. hallii, where the CDS length was the longest . Therefore, the detected cDNA variations were due to the length of untranslated regions (UTRs) in the cDNAs.The gene structures for PHO1 . However, each PHO2 had 15 exons with 14 introns  in monocots and 16 exons with 15 introns in dicots.The number of introns and exons also displayed some differences among  species . Each PHPHO1 were generally shorter than those of introns in PHO2 where these were found to be larger in size ranging from 77 to 4638 bp (except for the first intron of PHO1 in monocots). The intron 11 of the PHO1 of Z. mays was found to be the longest among all PHO1 of monocots and dicots (2092 bp). Likewise, the intron 13 of the PHO2 of S. tuberosum was found to be the longest among all PHO2 of monocots and dicots (4638 bp). The variations in the exon length were found to be relatively low, ranging from 77 to 476 bp for PHO1 and 77 to 492 bp for PHO2. The Exon 12 of the PHO1 in S. lycopersicum was the shortest (77 bp), whereas the exon 15 was the longest (476 bp). Likewise, the exon 4 of PHO2 was the shortest (77 bp) and the exon 15 of PHO2 was the longest (492 bp) in O. sativa.The difference in the size of introns and exons was also observed. The introns in PHO1 of all monocots and dicots. However, only intron phase 0 and intron phase 2 were found in the PHO2 of all monocots and dicots (PHO1 and the PHO2 (except the PHO1 of S. bicolor). For both PHO1 and PHO2 phases, phase 0 was the most dominant in all the examined species, ranging from 71.42–78.57% for PHO1 and 78.57–80% for PHO2. The average sequence similarity for exons in PHO1 was found to be higher in monocots (82.84–85.31%) than in dicots (33.18–69.50%). However, the average sequence similarity for introns was low in both monocots (36.15–39.40%) and dicots (23.23–33.47%)  and 20% to 32.1% in dicots (Each type of intron phase was found in the d dicots . An iden–33.47%) . For PHOn dicots .PHO1 and PHO2 of O. sativa on chromosome number 3 and 1, respectively. For PHO2, some degree of synteny conservation was observed for Z. mays, S. italica, T. aestivum, H. vulgare, B. distachyon, and S. bicolor. However, for PHO1, some degree of synteny conservation for only Z. mays. and P. hallii was observed. The synteny of 12 of the 30 genes flanking on the PHO1 of O. sativa was shared on the parallel chromosome 1 in Z. mays and chromosome 9 in P. hallii. Similarly, the synteny of 16 of the 30 genes flanking on O. sativa PHO2 was shared on the parallel chromosome 3 in Z. mays, 16 of the 30 genes on chromosome V in S. italica, 19 of the 30 genes on chromosome 3A in T. aestivum, 17 of the 30 genes on chromosome 3H in H. vulgare, 19 of the 30 genes on chromosome 2 in B. distachyon, and 21 of the 30 genes on chromosome 3 in S. bicolor. The microsynteny analysis in terms of the nucleotide for PHO1 and PHO2 has already been described earlier in the gene structure comparison section  apparently responded to hormones such as abscisic acid (ABA) and abiotic stress. Regulatory elements that induced the tissue-specific expression such as “endosperm expression” were also identified .Cis-regulatory elements were identified through promotor analysis of about 1 kb upstream region of both entified . TATA boO. sativa showed higher similarity for PHO2 (89.2–90.4% in monocots and 75.0–77.8% in dicots) than for PHO1 (84.3–87.5% in monocots and 67.0–69.3% in dicots). PHO2 is found to be more conserved than PHO1.An extra stretch of about 78–82 aa residues was found in the middle region of PHO1 and not in PHO2; while for both PHO1 and PHO2, the length of the protein sequences was almost similar in all monocots and dicots, ranging 962–985 aa in PHO1 and 832–897 aa in PHO2 . The extS. bicolor than in other species. PHO1 had two conserved domains (CDs): GT-35-Glycogen-Phosphorylase (97–950 aa) and a unique L80 domain (500–600 aa). The L80 domain was hyper-variable and predicted to consist of a PEST motif  [P. halli  ,32. SimiP. halli . The traP. hallii than in any other species. Unlike the lower conservation for PHO1, aa residues in PHO2 were more conserved for each of the 12 examined species. However, just like PHO1, PHO2 also possessed hyper-variable N-terminal residues in all species (PHO2 was relatively longer in  species . PHO2 waH. vulgare (PDB id: 5lr8.1.A) and the PHO2 of A. thaliana (PDB id: 4beq.1.A) as templates, respectively. All generated structures had a high level of confidence, as evident from the following observations  structures of PHO1 and PHO2 for all 12 species were generated using the PHO1 of rvations : (a) relrvations .O. sativa ranging from 85.23% to 94.34% for PHO1 and 89.12% to 94.34% for PHO2. In addition, a high similarity level of intrinsic physical and chemical properties was also observed, ranging from 56.56% to 97.94% for PHO1 and 70.45% to 99.27% for PHO2 in each of the mentioned species. For PHO1, the root mean square deviation (RMSD) value was 2.04–5.68 Å in monocots and 2.10–3.87 Å in dicots. For PHO2 this was 0.04–1.63 Å in monocots and 0.25–0.37 Å in dicots. The main protein core regions of PHO1 and PHO2 were favorably superimposed to the reference structure except for the L80 domains in PHO1  analysis indicated that the expression level of PHO1 was the highest in the endosperm and the lowest in the anthers. Unlike PHO1, the expression level of PHO2 was the highest in the embryo and the lowest in the pollens. The results indicated that the expression level of PHO1 was low in the early stages of seed development, highest at 12 days after pollination, and then decreased until the end of the seed development. However, the expression level of PHO2 remained the same throughout the seed development and peaked at 24 DAF  during the seed development in Z. mays, as the availability of PHO1 correlates with these enzymes [PHO2 was found to be primarily expressed during seed germination. Various motifs were identified in the promoter regions of starch phosphorylase genes. The expression level of both isoforms of PHO under ABA treatment could be upregulated in Z. mays as suggested by the experimental results. In contrast, the expression level under different stress conditions varied much among several species.Among both isoforms, PHO1 has been intensively investigated due to its main role in the growth and development of plants. In the present study we isolated the  enzymes ,34,35, wH. vulgare (only known structure of dimeric PHO1) and PHO2 over the PHO2 of A. thaliana (only known structure of dimeric PHO1) showed the accuracy of the structures and confirmed the identity of the true orthologs identified in the study.PHO2 is found to be more conserved than PHO1 at both protein and gene levels. The higher similarity in PHO2 might be due to its functional conservation, which was nearly reported as similar in various species. Moreover, the variations in PHO1 could be attributed to its varying functions ,28,36. TPHO1 remained constant during evolution, except in S. tuberosum (seven exons and six introns). An additional exon and intron were found in the PHO2 of dicots. After the divergence of monocots and dicots from a common ancestor [The sequences of genes for PHO1 and PHO2 of monocots and dicots varied and were found to be more conserved in monocots. The number of introns and exons of ancestor , exon loancestor , which wZ. mays, S. bicolor, P. hallii and S. italica, suggested that the chromosomes carrying the genes for PHO1 had undergone a massive reshuffling during evolution. The retention of some degree of synteny and collinearity in S. bicolor, S. italica, and P. hallii was understandable as these were more related to Z. mays compared with other evaluated species [H. vulgare, T. aestivum, and B. distachyon was surprising as extensive conservation was reported in grasses [The lack of shared gene content (synteny) and gene order (collinearity) in most of the monocots and dicots, except in  species . However grasses , as seen grasses ,45 also  grasses ,45,46,47cis-regulatory elements have been prospected previously in the promotor region [PHO1 and PHO2 might be responsible for the high expression level during the endosperm development. The prospected response elements in the present study need to be validated using wet-lab to determine the functional significance.Several r region ,37. We aPHO1 transcripts in various tissues and seed developmental stages among H. vulgare, O. sativa, and A. thaliana. The higher expression of PHO1 in the developing endosperm during the anthesis and grain filling period, and the lower expression in vegetative tissues, suggested its role in starch metabolism in Z. mays. Similar results were reported in T. aestivum [O. sativa [H. vulgare [PHO2 of Z. mays suggested that it could mainly involve the degradation and maturation of starch, as the expression pattern was found to be relatively higher in the lateral stages of endosperm development. These results are agreeable with the PHO2 of H. vulgare [T. aestivum [PHO1 was similar in the reported cereal crops, indicating that PHO1 might play the identical role/activity in the metabolic pathways in each of the examined species, as the availability of PHO1 correlates with the expression levels of other starch biosynthetic enzymes in higher plants [PHO1 and PHO2 in leaves have not been properly characterized. However, a study on the knockout mutant of A. thaliana (lack of PHO1) have found no alteration in starch and sugar metabolism and suggested that hydrolysis, rather than phosphorylsis, may be the major route of degradation in the chloroplast [Microarray-based data have indicated the uniform pattern of aestivum , O. sati. sativa , and H.  vulgare . The exp vulgare  and T. aaestivum  and it waestivum . In addir plants . The expr plants , howeverr plants . The imporoplast . In addiPHO1 and PHO2 are proposed to have the regions (in promotors) that have functions in ABA-induced expression, but a study on PHO1 of H. vulgare suggested no effect of ABA on the expression of PHO1 but up-regulation of PHO2 [A. thaliana significant down-regulation for both isoforms were detected. In contrast, it is found that ABA can up-regulate the expression of both the PHO1 and PHO2 in Zea mays. The effect of abiotic stresses on the expression of PHO has not been determined for various crops and could be worthy of investigation. For PHO1 and PHO2 in maize, ABA-induced expression changes might be the same according to phylogenetic analysis and aa residue alignments.All studied  of PHO2 . HoweverO. sativa were used as a reference in tBLASTx to identify “true” orthologs of PHO1 and PHO2 encoding genes in various monocots: Zea mays (Z. mays), Setaria italica , Panicum hallii , Brachypodium distachyon (B. distachyon), Oryza sativa (O. sativa), Hordeum vulgare (H. vulgare) and dicots; Arabidopsis thaliana , Solanum lycopersicum (S. lycopersicum), Solanum tuberosum (S. tuberosum), and Capsicum annuum (C. annuum) according to the criteria described in [https://www.ncbi.nlm.nih.gov/, accessed on 5 January 2022), EMBL , and Ensembl .Full-length cDNA and protein sequences of PHO in ribed in . Brieflyhttps://www.sciencebuddies.org/, accessed on 1 January 2022). To evaluate the simple sequence repeats (SSRs) and retro-elements, a repeat masker 4.0.5  was used with the default setting. The cis-regulatory response elements were identified in 1 kb upstream genomic regions of the translation start site using the PlantCare bioinformatics tool [Genomic DNA and CDS were used to determine the intron–exon junctions in full- length gene sequences. The intron phases  were marked according to their position relative to the reading frame: intron insertion between two codons (phase 0), intron insertion after the first base pair of the codon (phase 2), or intron insertion after the second base pair of the codon (phase 3). Both exon and intron regions were employed to measure the GC content by GC calculator . An aa present in all orthologs at a specific position was used in consensus sequence generation. Maize aa was used in consensus sequence if a different aa was found at the position. Insertions were also added to the consensus sequence that was relative to reference species [http://www.ncbi.nlm.nih.gov/Structure/cdd/wrpsb.cg, accessed on 1 January 2022).All orthologs for PHO1 and PHO2 were used in multiple sequence alignment to generate the consensus amino acid (aa) sequence through DNAMAN software with default settings , PROCHECK to check the aa in favored regions relative to other regions [H. vulgare and the PHO2 of A. thaliana, respectively.The Swiss model of the automated mode was used to generate the 3D structures of PHO1 and PHO2 using their aa sequences. The generated 3D structures were subjected to geometric and energetic verifications, and for this purpose, the following servers were used; structure analysis and verification server (SEVES)  online software [Scrutiny for the ligand-binding sites was conducted for both PHO1 and PHO2 using the 3DligandSite  using blocks of genes associated with the PHO1 and PHO2 of O. sativa.MEGA7  was emplZ. mays was selected to identify the expression level and the effect of ABA treatment on the expression level of PHO1 and PHO2. The inbred line was grown under the normal field conditions at Chongzhou Research Base of Sichuan Agricultural University, China. The materials were collected at 2-day intervals and preserved at −80 °C for experiments.Mo17 inbred line of O. sativa, H. vulgare, and A. thaliana) was carried out using the “Genevestigator” microarray database. In the case of Z. mays, the expression analysis in different tissues was carried out using the expression level data determined by RT-qPCR. The extraction of RNA, cDNA synthesis, and expression analysis were carried out as described by Jian M. [GAPDH gene encoding glycerinaldehyde-phosphate dehydrogenase was used as internal reference. The following primers were used to measure the transcript level of PHO1: Fwd: CTAACAGGACAATATGCA; Rev: GCTTCATTGGCCTTGGCA. The following primers were used to measure the transcript level of PHO2: Fwd: ATGAGTGCGGCGGCGAA; Rev: CTTGGCAATGCGCTGCTTCA. In silico expression analysis of the genes for PHO1 and PHO2 of the main cereal crops ( Jian M. . The GAPThe middle seed of corn cob 15 days after self-pollination of Mo17 was placed in a liquid MS medium containing 50 μmol/L ABA to slowly shake (50 rpm) for 24 h. At the same time, the seeds were cultured in the MS medium without ABA as the control. Some seeds were taken out at indicated time points , quickly frozen with liquid nitrogen, and stored for an RT-qPCR experiment.


Therefore, the dual objectives of improving the mechanical properties of pervious concrete with favorable permeability and reusing solid waste were achieved.The recycling of waste ceramic foams as fine aggregates to prepare a high strength pervious concrete (HSPC) was investigated. The as-obtained pervious concrete that was made using the waste ceramic foams presented promising results, with a high compressive strength of 36.54 MPa at 28 d and a favorable permeability of 3.8 mm s The recycling of waste ceramic foams as fine aggregates to prepare a high strength pervious concrete (HSPC) was investigated. While vigorously developing the ceramic foam, waste accumulation has progressively formed from discarded ceramic foam, leading to serious impacts on the surrounding environment.Ceramic foams have become popular porous materials owing to the combination of being lightweight, their incombustibility, heat and sound insulating, as well as being chemically stable.11 All the coarse aggregates are wrapped in paste and are then bonded together to form an entity with interconnected macro-voids.12 Therefore, pervious concrete can feature strong permeation and effective noise absorption.13,14 These exceptional advantages make pervious concrete one of the promising materials for sustainable infrastructure applications, including in sidewalks, alleys, plazas, gardens and in parking lots.15,16 However, pervious concrete with a porosity of 10–35% presents an unsatisfactory strength (28 d compressive strength hardly exceeds 35 MPa), and thus a high strength pervious concrete with acceptable permeability remains a tough challenge. Although extensive work has been done to improve the strength, most of the previous research has focused on the concrete porosity,17,18 the water to cement ratio,19 paste characteristics,20 the content and size of the coarse aggregates,21 and few studies exist that explore the role of fine aggregates, which are especially important for the structure and strength of pervious concrete.Pervious concrete is obtained from coarse aggregates and minor paste with little or no sand.The purpose of this paper is thus to carry out an innovative study to increase the compressive strength without causing deteriorating porosity or permeability. To this end, discarded ceramic foam was crushed and used as fine aggregates for making a high strength pervious concrete (HSPC). For comparison, traditional pervious concrete (TPC) without fine aggregates was prepared as well. The compressive strength, porosity and permeability of both samples were characterized and were analyzed in detail.2.2.1−3 and water absorption of 0.2% were employed. The crushed waste ceramic foams with a particle size of 0.5–4 mm were selected as the recycled fine aggregates (RFA), as shown in the inset of 2, PDF No. 46-1045) and tridymite , as seen from the XRD pattern in The as-received ordinary Portland cement (OPC) 42.5 R was used. Natural coarse aggregates (NCA) with an average size of 5–10 mm, a specific gravity of 2810 kg m2.23. Subsequently, the concrete specimens were stored with a relative humidity of 95 ± 5% at 20 ± 2 °C. After 24 h, the samples were removed from the molds and were then cured for 28 days.The preparation process of the HSPC sample is described in 2.3via the cold-water saturation method, according to ASTM C642-2006. The water permeability was measured by the constant hydraulic testing method, based on CJJT135-2009. The compressive strength of the samples was obtained, according to GB/T 50081-2002. A mean and standard deviation were obtained from the five measurements, to ensure the accuracy of the reported results.The porosity of the pervious concrete specimen was tested 3.−1 to 3.1 mm s−1. Thus, the incorporation of discarded ceramic foam as a fine aggregate did not affect the porosity and permeability much, but it produced a significant increase in the compressive strength. Such a result is exciting, because the as-obtained HSPC had more desirable permeability even at a much lower porosity in comparison to TPC, and this could be due to the structural change as a result of the incorporation of RFA. Meanwhile, the waste ceramic foams exhibited porcelain quality with high strength after firing at a high temperature,22,23 thus contributing to the improvement of the whole strength of HSPC.et al.14 prepared pervious concrete that displayed favorable mechanical strength, accompanied with ample thermal- and sound-absorption, by replacing natural coarse aggregates with recycled concrete and coal bottom ash. Meanwhile, Yeih et al.16 investigated that pervious concrete with coarse aggregates of electric furnace slag showed desirable mechanical and permeable properties compared to that made with gravels.Recent reports on the recycling of solid wastes instead of natural coarse aggregates in pervious concrete have been documented. For example, Ngohpok 24 and various strategies have been employed by researchers aiming to improve the strength of pervious concrete, including the construction of physical interconnected pores for prefabricated reactive powder concrete,25 the optimization of aggregate type and size,26 air-cooling electric arc furnace slag as aggregates instead of natural river gravels,27 the use of polymeric composites28 and an ultra-high performance matrix,29 as well as the incorporation of silica fume and ultra-fine silica powder,28etc. It is worth noting that the possibility of recycling discarded ceramic foams as fine aggregates and producing a pervious concrete with high strength and favorable permeability has been achieved, however the porosity of the pervious concrete has remained underdeveloped. Despite this, such a pervious concrete with a multi-level porous structure stands a good chance in finding broad prospects for applications.In contrast to the previous reports, the typical compressive strength of conventional pervious concrete with porosities between 15% and 30% ranges from 7 to 25 MPa,4.−1 compared to the traditional pervious concrete without fine aggregates, achieving the dual objectives of improving the mechanical properties of pervious concrete with favorable permeability whilst reusing solid wastes. In contrast to previous reports on pervious concrete, the possibility of recycling waste ceramic foams and producing a pervious concrete with high strength and favorable permeability has been presented, and further research regarding the effect of type and size of waste foam ceramics, as well as the durability of HSPC, will be carried out in the future.High strength pervious concrete (HSPC) was fabricated by recycling discarded ceramic foam as fine aggregates. It has been demonstrated that the as-obtained HSPC presented promising results with a high compressive strength of 36.54 MPa at 28 d and favorable permeability of 3.8 mm sThere are no conflicts to declare.


Concrete production consumes enormous amounts of fossil fuels, raw materials, and is energy intensive. Therefore, scientific research is being conducted worldwide regarding the possibility of using by-products in the production of concrete. The objective is not only to identify substitutes for cement clinker, but also to identify materials that can be used as aggregate in mortar and concrete productions. Among the potential alternative materials that can be used in cement composite production is rock dust of different geological origin. However, some adversarial effects may be encountered when using rock dust regarding the properties and durability of mortars and concrete. Therefore, comprehensive research is needed to evaluate the adequacy of rock dust use in cementitious composite production. This paper presents a comprehensive review of the scientific findings from past studies concerning the use of various geological origins of rock dust in the production of mortars and concrete. The influence of rock dust as a replacement of fine aggregates on cementitious composites was analyzed and evaluated. In this assessment and review, fresh concrete and mortar properties, i.e., workability, segregation, and bleeding, mechanical properties, and the durability of hardened concrete and mortar were considered. The industrialization and advancement of society generate large quantities of waste, creating a significant impact on the environment. Worldwide, waste generation has increased greatly in recent years and shows no signs of slowing down, other than the temporary effects of the COVID19 pandemic in construction. Each year, approximately 2.01 billion tons of municipal solid waste are generated worldwide, at least 33% of which is not well managed in terms of being environmentally friendly [Industrial and economic development has intensified activities in the construction industry, demanding an increase in the production of building materials. It is undeniable that concrete is the most extensively and generally used construction material worldwide. The continuous rapid growth of urban areas and infrastructure has led to an increase in demand, and this puts excessive pressure on the concrete industry for the production of large quantities of concrete to meet that demand. According to data compiled by the U.S. Geological Survey in 2019, the yearly global production of Portland cement was about 4.1 billion mt and it is forecasted to increase to 5.8 billion mt in 2050 ,4. AssumThere is a sort of material that can be utilized not only as a substitute for cement clinker, but also as a substitute for natural raw materials for the production of building materials ,7,8,9. IThe following sections of the manuscript present and synthesize the findings of various studies when rock dust is to be used as a replacement of fine aggregate in mortars and concrete.Aggregate is defined by the European standard EN 12620  as granuApproximately 4 billion mt of aggregates are produced and consumed in Europe and almost 91% of these aggregates are obtained from natural deposits . In the According to the European standard EN 12620 , naturalStandards adopted by agencies in various countries contain guidelines regarding the limit content of dust in aggregate to be used in the production of concrete. The European standard, EN 12620 , presentThe characteristics of mineral dusts presented in this review were limited to dusts from limestone, marble, granite, and basalt rocks, which represent the most rock dust in concrete production and thus examined on past studies. Marble is formed by the metamorphism of limestone and dolomite over a wide range of pressures and temperatures. In the process of grain recrystallization, carbonate sedimentary rocks are transformed into crystalline rocks. Thus, petrographically, marble is a limestone. However, in published studies on the use of rock dust in cement composites, a distinction is made between limestone dust and marble dust. Therefore, in this paper, it was also decided to keep such a division. The oxide composition of rock dusts is presented in Natural rock dust from rock fragmentation has a rough surface, sharp edges, and irregular shapes. Examples of the texture of limestone, marble, and basalt rock dusts observed under a scanning electron microscope are shown in A question arises whether, in light of the applicable standards, rock dust can be used and classified as additive for mortars and concrete. In the case of fillers or fine aggregates, their suitability for use in concrete is determined on the basis of EN 12620  and EN 1Thus, it should be stated that, considering the applicable standards, the addition of dusts as mineral fillers in the composition of mortars and concretes is determined by these cement composites properties, which may not be affected by the addition of dusts.The use of stone dusts as filler in concrete has a significant effect on workability. Fine filler additives in appropriate quantity improve the workability of cementitious materials and may not increase the water requirement ,60. HoweSegregation and bleeding in cement-based materials are two effects related to the loss of homogeneity. Segregation is observed as the settlement of aggregates within the mortars and concrete. Bleeding is associated with excess water rising to the surface of a highly fluid concrete mixture. Bleeding and segregation can be controlled by using well graded aggregates, finer cement, proper water to cement ratio, entraining agents, and mineral additives . UniformFurther, air content is a very important ingredient for cementitious materials because it directly affects the mechanical and durability properties cementitious materials. Cementitious based composites contain two types of air, namely entrapped and entrained. Entrapped air occurs naturally in the mix during mixing operations. These voids are convoluted and interrelated. On the other hand, entrained air is formed by the addition of air entrained admixture into the mixture. Those voids are spherical in form and independent from each other. In a conventional concrete (non-air entrained concrete) with a suitable mixture and sufficient compaction, the air content is around 1.5–2%. Air content can be increased up to 4–8% by using air entrained admixture for the improvement of freeze-thaw resistance for cold weather concreting ,75. The It is seen that there are conflicting interpretations in the literature on workability, but in general, the use of fillers affects the workability negatively by effectively changing the water/cement in the concrete. For this reason, when stone dust is used, preliminary tests must be performed, and water/cement adjustment must take into account the stone dust used instead of the fixed water-cement ratio. In addition, it is seen that there is a consensus in the literature that the effect of stone dust on segregation and bleeding resistance is very significant. It is also seen that the use of stone dust reduces the air content by filling the voids in the concrete. Although this situation seems positive in terms of reducing the permeability of concrete, it should also be investigated in terms of durability problems, such as freezing and thawing.The introduction of stone powder, which partially replaces fine aggregate, affects the properties of mortar and concrete physically and mechanically. The relative compressive strength of mortar and concrete with rock powder addition at a different curing age are shown in The filler role of stone powder is primarily responsible for the improvement in strength in cement composites with rock dust addition. As mentioned earlier, the process of the heteronucleation of cement clinker hydrates on dust particles mechanically improves the cement matrix microstructure and interfacial transition zone ,114,115.Rock dust is an inert filler and thus contributes in filling a greater range of the intergranular free space in cement composites. This results in the densification of the cement matrix, which leads to lower porosity and therefore higher strength ,106,118.Uchikawa et. al.  indicate3 and alite C3A available in the cement [In the case of limestone and marble powder, the development in concrete’s compressive strength is connected with the physical and chemical effects of dust. The dominant reason is due to the physical filler effect of mineral powder. This results in filling the spaces between the cement grains and refining the pore structure, enhancing the concrete matrix microstructure, and thereby a strength increase. The chemical effect of limestone and marble powder concerns the reaction of calcium carbonate CaCOe cement  and resue cement ,92. Thise cement ,123,124.e cement ,126.However, with a certain rock dust content replacing fine aggregate, decreases in the mortar and concrete strength were observed ,127,128.In general, the addition of rock dust has a positive effect on the strength as it fills the concrete voids and reduces the porosity. In addition, when the water/cement ratio is not modified according to the added stone powder, since the water required for cement hydration is used by rock dust, it can significantly reduce the compressive strength as well as the workability of the concrete.Few studies have addressed the impact on tensile and flexural strength of cement composites with rock dust addition as a fine aggregate. Overall, an increase in the rock powder replacing fine aggregate, an increase in tensile and flexural strength were observed ,130,131.However, above a certain amount of stone dust replacing sand , a decrease in h is observed. The increased fine content may also increase the pores in the concrete, which explains the flexural strength reduction ,136.Results similar to compressive strength in tensile and flexural strength appear in the literature, but the most important issue here is the rough surface texture and irregular shape of rock dust used.Galetakis and Soultana , as wellAs mentioned earlier, the water absorption of concrete affects concrete durability. The ability of water absorption depends mainly on the distribution, size, shape, and tortuosity of pores, as well as their continuity . StudiesFurther, the dissolution of compounds or chemical reactions between concrete and substance constituents occurs due to a chemical attack . The mosKępniak et al.  noticed Concrete production is associated with environmental concerns since it consumes large amounts of raw materials, energy, and labor. Thus, worldwide there is an urgent demand to use by-products in building material production. In addition to materials that can be used as aggregate in the production of mortar and concrete, materials that can be substituted with cement clinker are also sought. The potential alternative materials that can be used in cement composites production as fine aggregate substitution include rock dust of different geological origin. The management of this waste is currently a serious problem for producers of mineral aggregates, asphalt mixture plants, and dimension stone industry. This indicates that more research concerning the management and utilization of these waste products in cement composites production is required. The review of past studies in this area synthesized in this manuscript provided the following valuable conclusions that can be considered in further studies.The addition of rock powder significantly affects fresh concrete and mortar properties. The substitution for fine aggregate with rock dust leads generally to a significant decrease in workability. The much greater specific surface area of rock dust compared to fine aggregate results in a significant increase in water required by wet the particle surfaces, and thus poor workability. The solution to this problem is to use high water reducing admixtures to improve the workability of concrete. Therefore, there is a need to conduct research concerning the analysis of the influence of admixtures on concrete workability when the rock dust is used for fine aggregate substitution. As rock powder is very fine material, its addition leads to a reduction in bleeding and segregation. This is mainly the result of mix cohesion improvement by fine particles of rock dust and water retention enhancement.Improved mechanical properties of cement composites are due to the use of rock powder as a partial replacement for fine aggregate. The most important and dominant mechanism of beneficial rock dust interaction is connected with the filler effect, i.e., physical interaction. The space between the cement and aggregate grains is filled with very small particles of stone powder, which results in reducing the cement matrix porosity. With the addition of stone dust, the number of large capillary pores decreases and the content of small pores increases, which leads to sealing in the microstructure of the hardened cement paste and, accordingly, to a less permeable structure. As a result, cement composites with rock dust additive feature higher strength. Aside from the physical influence of stone dust on the cement matrix microstructure, other phenomena also occur. The rock dust grain surface is mainly the active center, which leads to the improvement of the properties and durability of cement composites from which heteronuclei of the C-S-H phase are formed. The heteronucleation on rock dust particles is much more favored by the fineness than geological origin of rock powder. As mentioned earlier, basalt dusts have some pozzolanic activity, which results in the increase of cement matrix density and thus strength improvement. In the case of using rock dust for fine aggregate substitution, the dominate role in property improvement is played by the filler effect, while the rock origin from which stone powder comes is less of importance. That is because analysed rock dust is in any case much finer than fine aggregate and possesses the greater specific surface area. The optimum fine aggregate replacement is about 20–30% and it depends more on rock dust fineness than its geological origin. With such a substitution level, an approximately 30% increase in mortar and concrete strength is observed.Reported results confirmed the positive effect of rock dust on concrete with an increase in the permeability and decrease in water absorption. Generally, the outcome is a result of the densification of cement matrix with fine rock powder particles, i.e., the filler effect. However, there were some contradictions regarding the influence of rock dust on permeability of concrete mainly to chloride ions. This depends on the finesses of the rock dust particles as compared to capillary pore and substitution level of fine aggregate with rock powder. In the case of sulphate attack, the addition of stone powder leads mainly to an improvement of sulphate resistance. Undoubtedly, further research is necessary to analyse effect of rock dust on cement composites durability, especially regarding chloride and sulphate corrosion, carbonation, and freeze-thaw resistance. Profound analysis concerning the influence of the fineness of rock dust on the penetration of chloride and sulphate ions is needed.Rock dust utilization in cement composite production requires the development of concrete design methods that allow to determine the optimal dust content in terms of obtaining the desired properties of both fluid concrete mix properties as well as hardened properties. Profound analysis is necessary to establish the optimum ratio for fine aggregate substitution with regard to the fineness of rock dust and addition of water reducing admixtures.Rock dust, which is currently considered as a by-product, can be used as a partial replacement for fine aggregates or even cement in cement mortars and concrete production. The utilization of rock dust waste is technically, economically, and ecologically justified and addresses the principle of sustainable development as it allows to reduce the consumption and dependency of natural resources for the production of cement composites and to manage the waste effectively.As a result, considering the extensive studies in the literature, it can be concluded that rock dust is an environmentally friendly material that contributes economically to the mixture of cement-based materials. The use of rock dust for fine aggregate replacement at a certain amount in cement-based composites improves many fresh and hardened state properties. Therefore, rock dust should be taken into account in the optimum mix design of cement-based composites. Most of the studies in the literature also mentioned that, in addition to improving the properties of concretes, using stone dust in concrete led to the consumption of by-products, thus providing a twofold benefit.When the results are evaluated for future studies, it is recommended that more research should be conducted on evaluating the usage of rock dust in high-performance concrete production and self-compacting concrete production, besides reactive powder concrete. The use of rock dust in the production process of cement composites requires the development of concrete design methods that allow the determination of the optimal rock dust content in terms of obtaining the desired properties of both the concrete mix and hardened concrete. If a careful analysis of the literature is performed, another important issue comes to the fore for future studies. Generally, the particle size distribution within the stone dust itself has not been taken into account by researchers. As known, it can be encountered in some cases that the particle size distribution in some intervals forms a significant part of the heap compared to other grain intervals. This situation directly affects many important parameters, such as water requirement, workability, gap-filling ability, etc., in concrete containing stone dust. For this reason, specifying the particle size distribution of these powder materials in studies instead of just calling them a material under 150 microns is recommended for future studies. A detailed analysis of particles size distribution can help to better interpret the results of the use of stone powder, as this affects the internal structure and many related properties.