IgG4-related disease (IgG4-RD) is distinguished by the infiltration of IgG4-positive plasma cells in a variety of tissues and organs. Even so, central nervous system lesions associated with IgG4-RD are scarce. We present a case of IgG4-related brain parenchymal lesions that mimics multiple sclerosis in a young girl.The patient was followed by our neurology and rheumatology teams. Clinical information was recorded, and the brain was screened using magnetic resonance imaging (MRI). During follow-up, we examined serum IgE, IgG and IgG4 and lymph node biopsy.Here, we presented details of a 14-year-old Chinese girl suffering from diplopia, left eyelid ptosis, right facial numbness, and right lower limb weakness admitted to our institute. Brain MRI revealed multiple sclerosis-like lesions in the brain parenchyma and spinal cord. During the follow-up, she developed lymphadenopathy. Elevation of serum, IgG, IgG4 and IgE and lymph node biopsy favors a diagnosis of IgG4-RD. The patient had a good response to glucocorticoids and mycophenolate mofetil. The literature review summarized eight previously reported IgG4-RD involving brain parenchyma.Our case expands the known age spectrum of IgG4-RD. The intracranial IgG4-RD is rare and could mimic multiple sclerosis. Careful examination and dynamic review of disease history are crucial in the differential diagnosis. The hlebitis . It can hlebitis . Multipl+ cells was over 220/HPF. Serum IgG4 was elevated . The patient was diagnosed as “IgG4-RD” and received oral glucocorticoid combined with cyclosporin but stopped 3 months later. The patient's family history was not remarkable. Based on the symptoms and MRI findings, the patient was suspected of MS and was given prednisone and intravenous immunogloblin (IVIG). Her diplopia and ptosis improved significantly and was discharged. One month later, she was administered 1 g of methylprednisolone for 5 days, followed by 70 mg of prednisone daily since her abnormal gait and lower limb weakness persisted. The prednisone was tapered to stop while recombinant interferon (IFN) β-1b was given every 2 days subcutaneously for 6 months. She did not receive any treatment for over 1 year until the development of enlargement of lymph nodes in the submaxillary and inguinal areas. Fourteen milligrams of Teriflunomide was given daily; however, her symptoms persisted. Six months later, the patient came to our department with lymph node enlargement and right-side numbness and weakness, but she denied any fever, unintentional weight loss, fatigue, or change in appetite. Laboratory tests revealed normal counts of leukocytes and platelets, the hemoglobin level, the albumin level, the serum creatinine level, and C-reactive protein. Antinuclear antibodies, extractable nuclear antigen antibodies, anti-neutrophil cytoplasmic antibodies, and anti-phospholipid antibodies were all negative. Serum IgG was 70.7 g/L , IgG4 was 28.5 g/L, and IgE was 4,810 mg/L , while IgA and IgM were within the normal range (+ plasma cells (>200/HPF) and an elevated ratio of IgG4+ cells to CD138+ plasma cells (~80%)  . No mycos (~80%) , 3.Our case illustrates an intracranial IgG4-RD mimicking MS in a 14-year-old girl, which has been rarely reported in the literature. In this case, it is important to make differential diagnoses among some relevant diseases including CNS tumor, infectious encephalitis, and immune-mediated encephalitis, such as MS.Some mimickers, especially idiopathic multicentric Castleman's disease (CD), are sometimes difficult to be differentiated from IgG4-RD  and shouIgG4-RD can affect almost every organ system, where 31% of patients were affected by hepato-pancreato -biliary diseases, 24% by retroperitoneal fibrosis and aortitis, 24% by head and neck-limited disease, and 22% by classic Mikulicz syndrome with systemic involvement . Nearly IgG4-RD can also involve the nervous system, including the central nervous system (CNS) and the peripheral nervous system. Neurological IgG4-RD has two main mechanisms: infiltration in the substance of the nervous system and compression of neurological structures by the mass effect of nearby diseased tissues . It mostNeural symptoms and white matter plaques on MRI of this patient  usually In addition to MS, the differential diagnosis of pseudo-tumoral brain lesions includes infection neoplastic, including primary CNS lymphomas and metastatic cancers; congenital, metabolic, or vascular diseases; and non-MS idiopathic inflammatory demyelinating diseases, which include neuromyelitis optica (NMO) spectrum disorders (NMOSD), opticospinal MS, and acute disseminated encephalomyelitis. NMOSD is characterized by simultaneous or consecutive attacks of acute optic neuritis and transverse myelitis . IgG autSimilar to MS, the exact pathogenesis of IgG4-RD remains elusive but aberrant innate and adaptive immunity are considered to be involved , 16. B cThis case report in conjunction with those in the literature indicates that IgG4-RD represents a great mimicker of many neoplastic, inflammatory, and infectious conditions. Histopathology remains critical to diagnosis because reliable biomarkers are lacking. IgG4-RD responds promptly to glucocorticoids and DMARDs, but prolonged courses are often needed because the disease relapses in most patients. This case illustrates the importance of dynamic monitoring and pathological examination to distinguish cerebral IgG4-RD from other CNS disorders and underscores the need for clear clinical guidelines to establish a diagnosis of IgG4-RD.The original contributions presented in the study are included in the article/This study was approved by the Ethics Committee of West China Hospital of Sichuan University. Written informed consent was obtained from the patient and her parent for the publication of any potentially identifiable images or data included in this article.PQ and BY collected the clinical information. CLiu interpreted the brain MRI findings. CLu made literature review and drafted the article. DF, YZ, YL, and CT interpreted the data and revised the article. All authors contributed to the article and approved the submitted version.This study was supported by the National Natural Science Foundation of China (Nos. 81501412 and 82104484), the Natural Science Foundation of Sichuan Province (2022NSFSC1542), the Post-Doctor Research Project, West China Hospital, Sichuan University (2021HXBH014), West China Hospital, Sichuan University 1.3.5 Project for Disciplines of Excellence, and West China Hospital, Sichuan University (No. ZYGD18015).The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.All claims expressed in this article are solely those of the authors and do not necessarily represent those of their affiliated organizations, or those of the publisher, the editors and the reviewers. 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Providers without formal training deliver healthcare and antibiotics across rural India, but little is known about the antibiotics that they stock. We conducted a cross-sectional survey of such informal providers (IPs) in two districts of West Bengal, and assessed the availability of the antibiotics, as well as their sales volumes, retail prices, percentage markups for IPs and affordability. Of the 196 IPs that stocked antibiotics, 85% stocked tablets, 74% stocked syrups/suspensions/drops and 18% stocked injections. Across all the IPs, 42 antibiotic active ingredients were stocked, which comprised 278 branded generics from 74 manufacturers. The top five active ingredients that were stocked were amoxicillin potassium clavulanate (52% of the IPs), cefixime (39%), amoxicillin (33%), azithromycin (25%) and ciprofloxacin (21%). By the WHO’s AWaRe classification, 71% of the IPs stocked an ACCESS antibiotic and 84% stocked a WATCH antibiotic. The median prices were in line with the government ceiling prices, but with substantial variation between the lowest and highest priced brands. The most affordable among the top five tablets were ciprofloxacin, azithromycin, cefixime and amoxicillin , and the most affordable among the syrups/suspensions/drops were azithromycin and ofloxacin , which are mostly WATCH antibiotics. IPs are a key source of healthcare and antibiotics in rural communities; practical interventions that target IPs need to balance restricting WATCH antibiotics and expanding the basket of affordable ACCESS antibiotics. E. coli, and 30% or more of Klebsiella in rural and urban settings, which are resistant to ciprofloxacin (a quinolone), and first-, second- and third-generation cephalosporins [The recognition of antimicrobial resistance (AMR) as a public health emergency has drawn attention to the need for the sustainable use of antibiotics . Globallosporins ,6,7, whiThe excessive and inappropriate use of antibiotics in humans and animals is an important driver of AMR . HoweverACCESS antibiotics should be available widely as first- and second-choice antibiotics for the management of common clinical syndromes; WATCH antibiotics should be used sparingly and should be carefully monitored; and RESERVE antibiotics should be used as a last resort to treat drug-resistant infections when all other antibiotics have failed.Furthermore, to reduce antibiotic misuse, the WHO’s Global Action Plan for Antimicrobial Resistance  recommenFor the large numbers of people in LMICs who lack access to the formal health system, informally trained private healthcare providers are an important source of primary care at first contact, especially for mild illnesses . Even phData on the availability and use of antibiotics from nonformal sources in India, or in other countries, remain scarce. The standardised data collection approaches for antibiotic availability and use are limited to registered retail outlets and health facilities ,37,38 anIn India, the role of IPs as a key source of antibiotics is well documented, but only one study has quantified the antibiotics that are dispensed/prescribed by a small number of IPs (12 IPs over 18 months) . MoreoveWe identified 291 IPs across our two study sites: 147 in Birbhum and 144 in South24Parganas. Of the 291 IPs, 16 said that they only prescribed and did not dispense antibiotics; a further 42 usually dispensed but did not have any antibiotics in stock on the day of the visit; and 37 were unwilling to disclose their stock. We therefore collected antibiotic stock data from 196 IPs: 104 in Birbhum and 92 in South24Parganas. Nearly all the IPs were male (98%) and 54% were between the ages of 35 to 55 years . A totalAmong the 196 IPs, 84% had antibiotic tablets in stock, 74% had syrups/suspensions/drops and 18% had injections. The IPs stocked a median of two antibiotic active ingredients in tablet form (IQR: 1 to 3), and one syrup/suspension/drops (IQR: 0 to 2) . As relaAcross all IPs, we documented 42 antibiotic active ingredients, across all formulations. The top five are shown in We grouped all of the available antibiotics by their anatomical therapeutic chemical (ATC) classification, which is a system that classifies drugs by their pharmacological and therapeutic properties  Figure . The mosWe further compared all of the available antibiotics with the WHO’s AWaRe list ; with thBeta lactam antibacterials, penicillins (J01C): examples include amoxicillin, ampicillin and amoxicillin + potassium clavulanate.Other beta-lactam antibiotics (J01D): examples include cefixime, cefpodoxime and cefadroxil.Quinolone antibacterials (JO1M): examples include moxifloxacin, norfloxacin, ciprofloxacin, ofloxacin and levofloxacin.Macrolides, lincosamides and stretogramins (J01F): examples include roxithromycin, erythromycin, lincomycin and azithromycin.Combinations of antibacterials (J01R): examples include azithromycin + cefixime, ofloxacin + ornidazole, cefixime + ofloxacin and ciprofloxacin + tinidazole. However, only two of these combinations—ciprofloxacin + tinidazole and norfloxacin + metronidazole—are listed under the J01R combinations. The rest are irrational combinations.Tetracyclines (J01A): examples include doxycycline, oxytetracycline and tetracycline.Aminoglycoside antibacterials (J01G): examples include amikacin and gentamycin.Note * Including antibiotics in Schedule H1 of the Indian Drugs and Cosmetics Act. This Schedule contains a restricted set of 46 prescription drugs, which include third- and fourth-generation cephalosporins, carbapenems, newer fluoroquinolones and first- and second-line antitubercular drugs. Sales of Schedule H1 drugs are more strictly monitored than those of Schedule H drugs [Banned drugs include drugs that are prohibited for manufacture and sale through gazette notifications under Section 26a of the Drugs and Cosmetics Act (1940) by the Ministry of Health and Family Welfare [ H drugs . Banned  Welfare .For each of the top five antibiotics for the different formulations , we presWe documented a total of 278 brands stocked : 118 for tablets, 141 for syrups/suspensions/drops and 19 for injections, which were produced by 74 different manufacturers from both Indian and global pharmaceutical companies. These were brands of off-patent generic products. The median retail prices for standard courses of treatment for an adult for the five most common antibiotics, for tablets and for syrups/suspensions/drops, are presented in There was substantial variation in the median price across the lowest and highest priced brands, particularly for some of the top five antibiotics, for both tablets and syrups/suspensions/drops . Among tThe median percentage mark-ups /sales price)) × 100) for the IPs for the top five antibiotics ranged from 15 to 22% for tablets, and from 10 to 20% for syrups, when all brands were included . HoweverWe estimated the local affordability of each of the top five antibiotics (tablets and syrups/suspensions/drops) by calculating the number of days’ wages of an unskilled agricultural worker in West Bengal in 2017  that wouAntibiotic stewardship efforts are hampered by a lack of data on antibiotic availability and usage, particularly from informal markets that are a major source of antibiotics in LMICs. There are several challenges that are involved in collecting medicine data from informal markets , includiThis single cross section has some limitations, as it does not capture seasonality and other temporal variations in antibiotic use, and, being limited to two districts in West Bengal, is not easily generalizable to IPs in other parts of the state and in India. The strength of our study lies in the collection of robust physically observed data on the antibiotics stocked in a cross section of IP clinics, which is a challenging task. A third limitation was that the data on the antibiotics that had been dispensed in the last seven days were based on recall. These could have been subject to recall bias, or they could have been underestimated by the IPs since they are not legally authorized prescribers. However, relative to the total daily patient load reported (median of 25), the scale of antibiotic dispensing is quite plausible. These sales data were collected towards the end of the survey, after our researchers had established good rapport with each IP, in order to minimize bias.The IPs in our study stocked 42 different types of antibiotics, which included both ACCESS (71%) and WATCH (83%) antibiotics . There wIn India, the central government caps the prices of 851 essential drugs , including several antibiotics . The medIn addition, we found low availability of older first-line ACCESS antibiotics, such as co-trimoxazole (trimethoprim/ sulfamethoxazole), ampicillin and doxycycline. Less than 10% IPs stocked these, and none stocked penicillin. These antibiotics have low overall availability in India. One recent study commented that few companies in India manufacture older ACCESS antibiotics . The autThe presence of the ‘not recommended’ irrational antibiotic combinations that were found in our study also reflected the wider Indian medicine market. Stocked by 21% of the IPs , these aWe found a large number of brands  in our study sites, and several different brands with the same antibiotic ingredients. This too reflects the nature of the medicine market in India, which abounds in branded generics. These are off-patent medicines that companies package and sell under different brands in order to promote brand loyalty . Growth A large percentage of the IPs in our study stocked both tablets (84%) and syrups/suspensions/drops (74%). In general, the syrups/suspensions/drops in our study cost more per adult treatment course than tablets, but, as many of these were paediatric formulations, a smaller (and more affordable) dose would have been required for most users. As paediatric DDDs are not available, we used adult DDDs in our analysis, but the fact that 74% of the IPs stocked syrups/suspensions/drops is indicative of the IPs’ key role in the management of childhood illnesses with antibiotics, as confirmed by other studies . Only 18The IPs in our study were low-volume stockists and dispensers, as was evident from the small numbers of DDDs that they stocked and dispensed. This is also suggestive of suboptimal dispensing, which has implications for fueling AMR. In our affiliated study , we descThis study was conducted in the state of West Bengal in eastern India. The state is divided into 19 districts; in 13 of these, more than 70% of the population is rural . We purpGiven the lack of an existing sampling frame of IPs, we chose to randomize clusters instead of IPs. Districts in India are divided into administrative blocks, and each block consists of a cluster of villages that is known as a ‘gram-panchayat’. We defined the clusters as gram-panchayats and adopted a census approach  by surveThe survey tool consisted of a provider questionnaire and an antibiotic stock sheet. The provider survey collected information on the IPs’ sociodemographic characteristics, backgrounds, training and the health services provided. The stock sheet collected information on all of the antibiotics stocked by the IPs, including tablets, syrups/suspensions/drops and injections; their brand names and manufacturers’ names; their pack sizes; their retail prices; the IPs’ purchase prices; the amounts dispensed in the last seven days; and the number of patients that were dispensed each antibiotic. The researchers requested that the IPs show all the antibiotics in their stock and transferred information from the packs onto the stock sheet. The purchase price of each antibiotic  and the sales volume, and the patients who received that antibiotic in the last seven days, were based on the IPs’ recall. The principal investigator (PI) trained the data collection team over four days of classroom training, which was followed by a round of field training. The team practiced developing rapport with the providers; the provider survey was completed before filling out the stock sheet because the latter was expected to be more sensitive. The tool was piloted twice in a nonstudy district with 17 IPs, and the final survey was conducted during February–May 2017. Each completed stock sheet was reviewed by the study coordinator, and a random sample was reviewed by the PI.The data were entered into Microsoft Excel and were analysed for the two districts by using Excel and Stata 14. This analysis only included IPs who had antibiotics in stock on the day of the visit and who provided consent (196 out of 291 IPs).Availability and Sales: The availability was calculated as the percentage of outlets stocking a specific type of antibiotic: by formulation , by active ingredient and by the ATC classification . The antFor the five most commonly stocked tablets and the five most commonly stocked syrups/suspensions/drops, we analysed the quantities that were in stock on the day of the visit and that had been dispensed in the last seven days, in terms of the defined daily doses (DDDs). The DDD is the assumed average maintenance dose per day for a drug for its main indication in adults . By the Price: For each of the five most stocked antibiotics, the median prices were calculated for a standard treatment dose for an adult for tablets and for syrups/suspensions/drops. For example, for amoxicillin, the assigned DDD is 1500 mg per day, so a standard course of treatment lasting 7 days will include 10,500 mg of amoxicillin. In practice, the duration of antibiotic therapy should depend on the nature of the infection and the response to treatment , and it The median prices are reported across all brands with a given active ingredient, and for the lowest priced, most stocked and highest priced brands in that category. These data are presented for the five most stocked antibiotics in their tablet and syrup formulations. The prices for injections were calculated per DDD, and not for full courses. Because of the small number of products, these data are presented in the text but not in Percentage markup for the IP: We calculated the percentage markup as the ((retail price–purchase price)/purchase price)) × 100 for the standard treatment dose for an adult for tablets and syrups/suspensions/drops.Affordability: The WHO/HAI propose assessing the affordability by comparing the median price for a standard adult dose with the daily wage of the lowest paid government worker. In the setting of rural West Bengal, we felt that the minimum daily wage of an unskilled agricultural worker   would beOur study provides new insights into the antibiotics that are stocked by rural IPs in India. The products that were available in the IP clinics reflected many of the characteristics of the larger medicine market in India, including the greater variety of affordable WATCH antibiotics, and several branded generics to choose from. The most stocked brands were priced in between the lowest and highest priced ones and they had more uniform provider markups across the brands, which suggests that markups were not the only consideration in the choice of antibiotics that were stocked; the price-to-user and the perceived product quality were also important factors. Potential interventions to improve the antibiotic practices in this setting will need to address the providers’ economic and social interests in dispensing drugs and antibiotics, and the lack of antibiotic use guidelines for providers at this primary level. Market factors, such as pricing policies for ACCESS and WATCH antibiotics and the restrictions on the number of irrational combinations, will need to be addressed by the government. Antibiotic regulations could be simplified through a closer alignment between the Indian H/H1 schedules and the WHO’s AWaRe classification. National and state governments could consider developing evidence-based policies to increase the availability of older-generation ACCESS antibiotics, and to restrict the use of WATCH antibiotics, corresponding to the local resistance patterns. To enable the responsible use of antibiotics by IPs, health and regulatory authorities will need to enable them to use some ACCESS antibiotics in the right way, while restricting the use of a large variety of broad-spectrum WATCH antibiotics, which is a practical approach that could lead to more effective antibiotic stewardship in LMIC community settings. This needs to be supplemented with market research on the low availability of some ACCESS antibiotics, and the measures to address this gap.


Concrete is known as the most globally used construction material, but it releases a huge amount of greenhouse gases due to cement production. Recently, Supplementary Cementitious Materials (SCMs) such as fly ash and Ground Granulated Blast Furnace Slag (GGBFS) have been widely used in concrete to reduce the cement content. However, SCMs can alter the mechanical properties and time-dependent behaviors of concrete and the early age mechanical properties of concrete significantly affect the concrete cracking in the engineering field. Therefore, evaluation of the development of the mechanical properties of SCMs-based concrete is vital. In this paper, the time development of mechanical properties of concrete mixes with various fly ash and GGBFS was experimentally investigated. Four different cement replacement levels including 0%, 20%, 30%, and 40% by fly ash and GGBFS as well as ternary binders were considered. Compressive strength, splitting tensile strength, flexural strength, and elastic modulus of concrete were measured until 28 days. Three additional concrete mixes with ternary binders were also cast to investigate the early-age autogenous shrinkage development until 28 days. In addition, prediction models in existing standards were used and compared to experimental results. The comparison results showed that the prediction models overestimated the compressive strength but underestimated the splitting tensile strength development and autogenous shrinkage. As a result, a model capturing the effect of fly ash and GGBFS on the development of compressive and splitting tensile strength is proposed to improve the prediction accuracy for current standards and empirical models. Concrete is known as the most globally used construction material due to its excellent performance of compressive strength and workability. The tensile strength of concrete can also be improved using rebar and fibres . Due to Numerous researchers have focused on the incorporation of SCMs such as fly ash and Ground Granulated Blast Furnace Slag (GGBFS) in concrete, which have an environmental affinity ,9. DepenIt has been reported that the addition of fly ash in concrete can alter the mechanical properties and time-dependent behaviours of concrete. Concrete mixes with fly ash at the content level of 50% can also provide advantages, including strong resistance to chloride and sulphate attack, less alkali–silica expansion, and low heat . AccordiOn the other hand, the report showed that adding GGBFS to concrete enhanced the long-term mechanical strength while also promoting the elastic modulus marginally. Furthermore, GGBFS can improve the concrete engineering properties by lowering shrinkage and creep as well as change the durability by enhancing abrasion resistance, reducing permeability, and greatly promoting the interactions between alkali–silica and sulfate . In addiThe mechanical properties of concrete at early age significantly affect the concrete cracking in the engineering field . In exisIn this study, 12 concrete mixes including various fly ash and GGBFS content were cast to investigate the mechanical properties and autogenous shrinkage of concrete. Four different cement-replacement levels  by fly ash and GGBFS were used to examine the influence of cement-replacement levels on the mechanical properties of concrete until 28 days. Three additional concrete mixes including ternary binders were also utilised to evaluate the early age concrete autogenous shrinkage. Prediction models in existing standards were utilised and compared to the time development of mechanical properties and autogenous shrinkage of concrete.2/kg in accordance with Chinese Standard GB 175-2020 [The raw materials in this study included Ordinary Portland cement (strength class 42.5) with a Blaine fineness of 375 m175-2020 . Two typ175-2020 , respectThe mix proportion of concrete in this paper is shown in The mechanical properties including compressive strength, splitting tensile strength, flexural strength, and elastic modulus of concrete for all mixes were conducted according to Chinese Standard GB/T 50081-2019 . The comThe size of autogenous shrinkage specimens is 100 mm × 100 mm × 400 mm. The specimens were demoulded at 24 h after casting and stored in an environmentally controlled room at a temperature of 20 °C ± 2 °C and RH of 60 ± 5%. As shown in The development of flexural strength of concrete was provided in The 7- and 28-day elastic modulus of concrete was provided in The development of the compressive strength of concrete in Eurocode 2 and FIB 2010 models ,32 is exThe development of the splitting tensile strength of concrete in Eurocode 2 and FIB 2010 models ,32 is exThe development of the elastic modulus of concrete in Eurocode 2 and FIB 2010 models ,32 is exThe incorporation of SCMs can influence prediction results as per ,32,57. Atandards ,32. TherRegarding autogenous shrinkage of concrete mixes with SCMs, three empirical models from standards are assessed in this study ,32,58. TThe expression of autogenous shrinkage of concrete in Eurocode 2  is shownThe autogenous shrinkage in FIB 2010  is estimIn AS3600-2018 , the autGGBFS used in concrete. It should also be noted that the Equations (10) and (11) can be used not only for concrete with fly ash or GGBFS, but also extend to concrete with ternary binders.As mentioned in the previous section, the effect of fly ash and GGBFS on concrete mechanical properties development should be considered in existing models. As shown in The evaluation and error values have been widely interpreted in many studies ,60,61. TFly ash and GGBFS reduced the early age mechanical properties of concrete, but the compressive strength and splitting tensile strength of fly ash concrete were similar to OPC concrete at 28 days, while GGBFS increased the compressive strength of concrete at 28 days. Both fly ash and GGBFS decreased the flexural strength and elastic modulus of concrete. When ternary binders were incorporated, the concrete also exhibited low mechanical properties.The model in existing standards overestimated the early age of compressive strength development but underestimated the splitting tensile strength of concrete, leading to an unreliable calculation for design purposes. As such, it is recommended to consider the effect of fly ash and GGBFS on concrete’s mechanical properties development.A model capturing the effect of fly ash and GGBFS on the development of compressive and splitting tensile strength was proposed. The statistical analysis of the comparison between predicted and measured compressive strength and splitting tensile strength showed a good agreement. The mean value and CoV are 1.00, 0.10, and 0.95, 0.17 for the The autogenous shrinkage of concrete mixes with fly ash and GGBFS was different from that of OPC concrete. The model in existing standards failed in predicting the early-age autogenous shrinkage development of fly ash and GGBFS concrete. As a result, a broader database of concrete containing fly ash and GGBFS values is recommended to improve and establish optimal parameters in existing models.The results presented in this work provide insight into the mechanical properties and autogenous shrinkage development of concrete mixes with various fly ash and GGBFS content. The observed trends and patterns of behaviour could be utilised to reflect the early-age behaviour of concrete. The main observations are as follows:


Scytosiphon lomentaria (SL) is a brown seaweed with antioxidant and anti-inflammatory properties; however, its effects on obesity are unknown. In this research, we investigated the anti-obesity properties and underlying mechanisms of the SL extract in vitro and in vivo. In 3T3-L1 preadipocytes, SL extract inhibited lipid accumulation, decreased the expression of Acc1, C/ebpa, Pparg mRNA and p-ACC1, and increased the expression of Ucp1 mRNA, UCP1 and p-AMPK. In animal experiments, mice were fed a chow diet, a high-fat diet , and high-fat diet with SL extract (150 and 300 mg/kg body weight) for eight weeks (n = 10/group). SL extract reduced HF-induced weight gain, epididymal fat weight, fat cell size, LDL-C, leptin, fasting glucose, and glucose tolerance. In addition, SL extract had comparable effects on mRNA expression in WAT and liver to those observed in vitro, thereby inhibiting p-ACC1/ACC1 and increasing p-AMPK/AMPK and UCP1 expression. Furthermore, SL extract decreased HF-induced Firmicutes/Bacteroidetes ratio and reversed HF-reduced Bacteroides spp., Bacteroides vulgatus, and Faecalibacterium prausnitzii. These findings suggest that SL extract can aid in weight loss in mice fed a high-fat diet by altering adipogenic and thermogenic pathways, as well as gut microbiota composition. Obesity is a chronic condition with energy imbalance and adipose tissue inflammation . AccordiScytosiphon lomentaria (SL) is a brown coastal alga with anti-inflammatory, antioxidant, and anti-cancer properties [It has been reported that seaweeds, particularly brown seaweeds, have anti-diabetic, anti-hypertensive, antioxidant, and anti-inflammatory properties, and they are associated with reduced hyperglycemia, cardiovascular disease mortality, and increased life expectancy ,8. Seaweoperties ,13. In poperties ,14. In Roperties . Until noperties . Regardioperties . All theMultiple pathophysiological mechanisms contribute to the development of obesity and metabolic syndromes. Adipogenesis increases cell number by inducing C/EBPα and PPARγ to promote the differentiation of preadipocytes , whereasS. lomentaria polyphenols, and their effects on gut microbiota have not been investigated.In addition, gut bacterial composition has been reported to be linked to obesity through modulation of energy production, storage, and consumption ,23. WestThe mechanisms underlying the effects of SL extract on 3T3-L1 cells and animal models of obesity caused by a high-fat diet were explored in this study. We hypothesized that SL extract reduces obesity by suppressing adipogenesis and lipogenesis, enhancing thermogenesis, and modulating gut microbiota.S. lomentaria purchased from ParaJeju . The levels of total phenolics and flavonoids were measured using the Folin-Ciocalteu [The 70% ethanol-extracted SL extract was obtained from Marine Biobank  or was isolated from dried iocalteu  and the iocalteu . The samiocalteu .2 in DMEM with 10% FBS, 2.5% HEPES, and 1% penicillin/streptomycin . The cell viability was quantified by Cell Titer Solution . The cells were seeded at 5000 cells/well (96-well), and next day, the cells were treated with SL extracts (0–100 mg/L) for 48 h. The MTS solution was then added for 2 h, and the absorbance was measured using a microplate reader at 490 nm  [3T3-L1 cells were supplied by the Korea Cell Line Bank . The cells were cultured at 37 °C and 5% COMA, USA) .3T3-L1 cells were cultured until they reached 100% cell confluency. Then, the cells were differentiated for 2 days in DMEM containing 10 µg/mL insulin, 0.5 mM IBMX, and 1 µM dexamethasone  (Days 0–2). The cells were then cultured in DMEM containing 10 µg/mL insulin (Days 3–6). The SL extract (0–20 mg/L) was added to the medium throughout the 6 days of cell differentiation period . Oil RedThe animal experimental design was approved by the Ethics Committee of PNU . Forty C57BL/6J mice , aged six weeks and weighing approximately 18–22 g, were supplied by Oriental Bio Co. . After acclimating for one week, mice were randomly separated into four groups: (1) chow diet (Con), (2) high-fat diet (HF), (3) HF with low-dose SL , and (4) HF with high-dose SL . The Con group was fed multigrain diet  for eight weeks, whereas the HF and experimental SL groups were administered an HF  . For eigAdipose tissue and liver were preserved in 4% formalin for 24 h and embedded in paraffin. After staining the sections with hematoxylin and eosin (H&E) and ORO reagents, four images were acquired of each stained slide using an Olympus microscope (JP/BXFLA). ImageJ was used to compute the area of fat cells  .Total triglyceride (TG), cholesterol (TC), and HDL-C levels in the serum were measured using kits . Total cholesterol levels were subtracted from HDL-C levels to determine LDL-C concentrations. Serum levels of leptin and adiponectin were detected using a kit  .RNA was extracted from differentiated 3T3-L1 cells, mice liver, and epididymal tissues of the mice using the RNeasy Mini Kit  and TRIzol (Thermo Fisher). Total RNA was reverse-transcribed to generate cDNA, which was synthesized with SYBR Green (Bio-Rad) using a CFX real-time instrument  for RT-qPCR. β-actin was used as the reference. The primers used are listed in n = 3–4/group) for 16S rRNA sequencing. The samples were purified and sequenced using the iSeq platform . Trimmomatic (ver. 0.39) was used to clean the sequences, and then the data were organized into operational taxonomic units and aligned with QIIME2 (version 1.9.5) (accessed on 15 December 2022) [n = 10 per group) [Bacterial DNA was isolated from feces using the PowerFecal Pro DNA Kit (QIAGEN). DNA from two mice was combined in equivalent proportions (er 2022) . In addir group) .g for 5 min at 4 °C. Then, 10 μg of cell protein and 50 μg of protein from mouse liver were loaded into SDS-PAGE and transferred onto membranes. Membranes were first treated in a blocking solution (5% nonfat milk), then with primary antibodies UCP1, AMPK, p-AMPK, p-ACC1, ACC1 (All 1:2000 dilution), and β-actin  at 4 °C overnight. After incubating with a secondary antibody, band intensities were calculated by utilizing a camera  and ImageJ software [Protein was extracted from the liver tissue and 3T3-L1 cells using M-PER and T-PER reagents (Thermo Fisher) with a protease inhibitor (Thermo Fisher) . After hsoftware .t-test was used to compute the p-values, and two-way ANOVA (Dunnett’s test) was performed to examine the effects of treatment and time on the change in mouse body weight. The non-parametric Kruskal–Wallis test was used for calculating the prevalence of certain gut bacteria. The significance level was established at p < 0.05.GraphPad Prism 9  was used for the statistical analysis. The findings are reported as the mean ± SD. One-way ANOVA (Dunnett’s test) or Student’s The total polyphenol content of the SL extract was 13.17 ± 0.48 mg GAE/g extract and the total flavonoid content was 23.75 ± 3.12 mg CE/g extract. LC-MS analysis of the SL extract identified active compounds, such as sinapic acid, catechins, quercetin, hydroxytrifuhalol A, acacetin, and caffeic acid .When we treated 3T3-L1 cells with the SL extract at concentrations ranging between 0 and 100 mg/L, their cell viability was higher than 80% at concentrations lower than 20 mg/L A. ConcenAcc1 by 63% and 40%, respectively , and the trend continued until Week 8. Compared to the HF group, SL extract consumption decreased body weight beginning at Week 6 in the HF-SLH group and at Week 7 in the HF-SLL group  and Srebp1 (28%) in WAT compared to the HF group. The low concentration of SL extract reduced the adipogenesis-related gene C/ebpa in the liver by 86% ; Con vs. HF-SLH: R = 1 (p = 0.028); HF vs. HF-SLH: R = 0.25 (p = 0.15); p = 0.02). At the genus level, the populations of Bacteroides spp. were reduced by the high-fat diet and increased by the SL treatment  [C/ebpa and Srebp-1c, by and enhancing the phosphorylation of AMPKα and ACC-1 [Seaweed extracts are an excellent source of bioactive compounds that aid weight loss . Catechi and Fas  and upred Prdm16 ,47. Cate, Pgc1a) ,49. Acacnd ACC-1 ,51. SL eC/ebpa, Pparg, Acc1 mRNA, and pACC1 protein while increasing Ucp1 mRNA, UCP1, and pAMPK protein. The accumulation of lipid droplets in adipocytes causes obesity. The suppression of the master regulators of adipogenesis, Pparg, C/ebpa, and Acc1 by SL extract is indicative of its potential anti-adipogenic and anti-obesity effects. In this mouse model fed a high-fat diet, SL extract lowered fat mass, body weight, and adipocyte size compared to the HF group. In epididymal fat tissue, lipogenesis-  and adipogenesis -related genes were decreased in the HF-SLH group compared to the HF group, although thermogenesis-related Ampk, Ppara, and Ucp1 genes were enhanced by SL extract. This reveals that SL extract can inhibit adipogenesis and lipogenesis similarly to 3T3-L1 cells. However, SL extract had minimal effects on adipogenesis and lipogenesis-related genes in the liver, and SL extract at a high dose only increased energy metabolism and thermogenesis-related genes Ampk, Pgc1a, Ppara, and Ucp1 compared to the HF group. This is likely because the liver has not yet accumulated lipids, as evidenced by histological scoring, but SL extract still had the potential to promote energy metabolism in the liver compared to the HF group. Consequently, by inhibiting lipogenesis and adipogenesis and promoting thermogenesis, SL extract may help prevent obesity.3T3-L1 cell differentiation is a well-established model of adipogenesis with lipid accumulation. During adipocyte differentiation, a number of transcriptional cascades are activated. PPARγ and C/EBPα, which are involved in differentiation and govern adipogenesis at an earlier level ,53, are Treating hyperlipidemia and hyperglycemia has the potential to treat and prevent obesity . In thesF. prausnitzii and B. vulgatus was only significantly decreased by the high-fat diet but increased by SL extract. B. vulgatus, belonging to the phylum Bacteroides, is the predominant gut microbial species depleted in obese individuals and plays a crucial role in maintaining a healthy gut ecosystem [F. prausnitzii is a probiotic that generates butyrate, an anti-inflammatory molecule that regulates the intestinal immune system, oxidative stress, and metabolism of colon cells [F. prausnitzii and B. vulgatus were negatively correlated with a number of obesity-related markers. In addition, the abundance of F. prausnitzii and B. vulgatus was significantly decreased by the high-fat diet but increased by SL extract. Therefore, SL extract exhibited anti-obesity effects by modulating gut microbiota composition.Dysbiosis of the gut microbiota is intimately associated with obesity and promotes the genesis and progression of obesity by increasing appetite, chronic inflammation, and fat storage in the host . Recent cosystem . F. prauon cells . In thisEcklonia cava ethanol extract (ECE), which has undergone extensive toxicity testing in conjunction with other brown algae. The NOAEL value for ECE is 750 mg/kg, which does not indicate toxicity [Prior to identifying the underlying mechanism of action, it is essential to establish the optimal dosage of bioactive chemicals. However, SL ethanol extract has only been tested on cells and zebra fish ,14,15,17toxicity . Accorditoxicity . In othetoxicity . In a setoxicity . This reOne of the experimental limitations was that that the analysis of the identified compounds in SL extract was a preliminary screening that requires additional experiments. Currently, we are in the process of establishing a library of components found in brown algae by conducting a literature review and estimating the substance by comparing the molecular weight and fragment pattern of the library based on the results of LC-MS analysis. Only six substances that could be clearly estimated have been identified in this study and the remaining peaks are still in the process of confirmation. On the basis of the peak area, the six substances were considered to be the primary components in SLE, as compared to other components, and to be most correlated with observed biological activity. However, additional confirmation is necessary. Another limitation was that this animal study lasted only eight weeks. There were no differences in liver weight among the groups, and there was no evidence of fat deposition in the liver. A recent study demonstrated that feeding mice an HF diet for 12 weeks induced hepatic steatosis , suggestScytosiphon lomentaria suppressed the expression of genes and proteins involved in adipogenesis, lipogenesis, and thermogenesis. In addition, treatment with SL extract ameliorated gut microbiota changes caused by a high-fat diet. Based on these changes, SL extract may have the potential to reduce obesity by altering adipogenesis, lipogenesis, thermogenesis, and gut microbiota composition, and SL extract can be used as anti-obesity agents.This investigation revealed that the SL extract reduced weight gain and WAT weight, reduced LDL-C, leptin, and improved glucose intolerance.


Immunoglobulin G4-related disease (IgG4-RD) is a systemic immune-mediated fibro-inflammatory disorder. Coronary IgG4-RD has been scarcely reported and may present as “tumor-like” lesions. These pseudo-masses may be underdiagnosed mainly due to a vague clinical picture that can vary from complete lack of symptoms to acute coronary syndrome or sudden cardiac death. Early recognition of coronary IgG4-RD is essential to monitor disease activity and prevent life-threatening complications. We report a comprehensive non-invasive imaging evaluation of a patient affected by coronary IgG4-RD, which was diagnosed as an incidental finding during routine pre-laparoscopic cholecystectomy checkup. Non-invasive imaging revealed the presence of a peri-coronary soft-tissue mass that was stable at 12 months follow-up. Immunoglobulin G4-related disease (IgG4-RD) is an emerging fibro-inflammatory condition with unknown etiology, characterized by lymphoplasmacytic infiltrate rich in IgG4-positive plasma cells, storiform fibrosis, tumor-like lesions and elevated serum IgG4 concentrations in 60–70% of patients . RecentlPeriarteritis, with involvement of large-to-medium-sized vessels, may also be a manifestation of IgG4-RD as well as inflammatory aneurysm formation. More rarely, this condition has been reported to affect small-sized vessels such as coronary arteries, leading to potentially life-threatening complications, such as acute coronary syndrome or sudden cardiac death. Histopathologic assessment is considered the method of choice to confirm the diagnosis of IgG4-RD; however, it can be challenging to perform biopsy or to obtain surgical samples when this disease involves vital structures. In these cases, non-invasive imaging evaluation of coronary IgG4-RD may play a crucial role both for the diagnosis and management of this condition .Since IgG4-RD involvement of coronary arteries has been scarcely described, our aim is to report multimodality non-invasive imaging findings of this rare entity and to present a review of the literature.A 63-year-old man came to our observation in May 2021 to perform a chest CT study for suspected pulmonary nodule previously detected on a chest X-ray during a routine pre-laparoscopic cholecystectomy checkup. The patient was asymptomatic for angor and dyspnea. Past medical history was significant for multiple comorbidities including obesity, dyslipidemia, arterial hypertension, gouty arthritis, multi-district arthrosis, chronic renal failure, phlebopathy of the lower limbs with dyschromia and trophic ulcerations and multinodular thyroid goiter. The patient reported remote tobacco use, past episodes of chest pain and no history of coronary artery disease.Chest CT did not reveal lung nodules but a peri-coronary “pseudotumor” as an incidental finding. Dual-energy coronary computed tomography angiography (DE-CCTA) was subsequently performed, and showed a soft-tissue mass within the anterior interventricular sulcus, which encased the distal tract of left main stem (LM), the proximal and the middle segment of the left anterior descending artery (LAD), the first diagonal (D1) and the proximal segment of the left circumflex artery (LCx), without causing any stenosis of the involved coronary segments and configuring the typical “pigs-in-a-blanket” sign . All corThe pseudo-mass did not show early enhancement or iodine uptake during arterial phase but had a tenuous late-enhancement at delayed phase A,B. Extended laboratory tests revealed mildly elevated IgG  and IgG4 levels  at turbidimetric assays, normal erythrocyte sedimentation rate, normal C-reactive protein levels, normocomplementemia, negative VDRL test and negative rheumatoid factor (RF) and antineutrophil cytoplasmic antibodies (ANCAs). Slightly high serum IgG4 levels raised suspicions of an immune-mediated disease.Cardiac MRI (CMR) was subsequently performed for a non-invasive characterization of the pseudo-mass. The lesion was isointense to myocardium in bSSFP cine-images, heterogeneously hypointense in T2-weighted sequences, and hypointense in T1-weighted sequences. The pseudo-mass did not present early enhancement during arterial first-pass perfusion imaging, but it showed late gadolinium enhancement (LGE), supporting the provisional diagnosis of a fibrotic/granulomatous lesion .In the suspicion of coronary IgG4-RD, the patient underwent a 18F-fluorodeoxyglucose (FDG) positron-emission tomography (PET) scan, which did not show an increased FDG uptake of the cardiac pseudo-mass C.In consideration of the complete absence of symptoms, the patency of coronary vessels and the good cardiac function, a biopsy was contraindicated because of the high procedural risk. Moreover, since the non-invasive imaging characteristics of the pseudo-mass were not consistent with active inflammation or malignancy, no surgical or pharmacological treatment was planned.The patient underwent DE-CCTA follow-up studies at 6 months and 12 months, which demonstrated substantial stability of radiological findings and good clinical condition .IgG4-RD is a systemic immune-mediated inflammatory disease typically associated with high serum IgG4 concentration and IgG4+ plasma cell infiltration that can involve several organs. The most common sites are the pancreas, salivary glands, retroperitoneal organs, and liver ,3.Cardiovascular system involvement may manifest with arteritis or periarteritis and inflammatory aneurysms of large-to-middle-size vessels. Coronary artery involvement  has rarely been reported in the literature, but over the past years its frequency has increased, probably due to the increasing availability of advanced cardiovascular imaging techniques. When this occurs, clinical presentation may vary from complete lack of symptoms to potentially fatal conditions such as acute coronary syndrome or sudden cardiac death .Currently, IgG4-RD diagnosis is defined by the Comprehensive Diagnostic Criteria proposed in 2012 by Umehara et al. and revised in 2020, which refer to specific clinical, radiological, serological and pathological findings [Serological findings imply detection of IgG4 serum levels > 135 mg/dL, which were considered critical for the diagnosis of IgG4-RD. Nonetheless, almost 30% of patients shows normal or mildly elevated IgG4 serum and their increase has shown to depend on the number of involved organs, and it is more common in case of pancreatic disease. Increased IgG4 concentration is also not specific for IgG4-RD, since other entities have also been associated with this laboratory finding  .Biopsy has always been considered the gold standard for the diagnosis of IgG4-RD, since it allows confirmation of the presence of the typical histological features characterized by lymphoplasmacytic infiltrate rich in IgG4-positive plasma cells and storiform fibrosis . AccordiIn our case, the lack of clinical symptoms and the benignity of the lesion assessed by comprehensive multimodality imaging suggested a biopsy should not be performed in such a critical anatomical site. As matter of fact, 2019 ACR/EULAR IgG4-RD classification criteria do not require confirmation by biopsy when there is a strong suspicion of IgG4-RD by clinical, serological and radiological findings [In our case, coronary CTA allowed for the direct visualization of the soft-tissue mass completely encasing the coronary vessels without causing their luminal narrowing. This finding configures the typical “pigs-in-a-blanket” sign, which is considered to be specific for coronary IgG4-RD .Dual-energy CCTA also provides additional parameters for non-invasive characterization of cardiac lesions ,13,14,15CMR findings in coronary IgG4-RD have been scarcely described , despiteConversely, in case of active perivascular inflammation, increased iodine density during arterial first-pass in DECT or increased signal intensity in T2-weighted sequences and early gadolinium enhancement in CMR would have been expected findings . Moreove18F-FDG PET/CT represents a remarkable tool to evaluate a systemic inflammatory disease and to highlight IgG4-RD localization for guiding the biopsy, or to monitor treatment response . Its maiThe first-line therapy in patients with symptomatic active IgG4-RD is glucocorticoids, which are extensively used for remission induction and disease relapse, but they can also be used for maintenance therapy. Steroid-sparing agents can also be used for remission maintenance when long-term therapies expose patients to glucocorticoid toxicities. A “watchful waiting” strategy is also suitable in asymptomatic patients and in case of highly fibrotic inactive lesions that are weakly responsive to pharmacologic treatments. In our case, the lack of clinical symptoms, together with laboratory and imaging findings, excluded the presence of active inflammation, and the patient did not require any pharmacological treatment. Moreover, in these patients, the risk/benefit balance may not encourage any therapeutic courses .Coronary IgG4-RD diagnosis is a rare and potentially fatal condition whose diagnosis is generally challenging. Non-invasive multimodality imaging plays a pivotal role for its diagnosis, since performing a biopsy might not always be an option due to the critical location of these lesions. Finally, non-invasive imaging is crucial to monitor disease activity and guide treatment.


Plant height (PH), spike length (SL) and spike compactness (SCN) are important agronomic traits in wheat due to their strong correlations with lodging and yield. Thus, dissection of their genetic basis is essential for the improvement of plant architecture and yield potential in wheat breeding. The objective of this study was to map quantitative trait loci (QTL) for PH, SL and SCN in a recombinant inbred line (RIL) population derived from the cross ‘PuBing3228 × Gao8901’ (PG-RIL) and to evaluate the potential values of these QTL to improve yield.QPh.cas-5A.3, QPh.cas-6A, QSl.cas-6B.2, QScn.cas-2B.2 and QScn.cas-6B explained 5.58–25.68% of the phenotypic variation. Notably, two, three and three novel stable QTL for PH, SL and SCN were identified in this study, which could provide further insights into the genetic factors that shape PH and spike morphology in wheat. Conditional QTL analysis revealed that QTL for SCN were mainly affected by SL. Moreover, a Kompetitive Allele Specific PCR (KASP) marker tightly linked to stable major QTL QPh.cas-5A.3 was developed and verified using the PG-RIL population and a natural population.In the current study, Five, six and ten stable QTL for PH, SL, and SCN, respectively, were identified in at least two individual environments. Five major QTL KASP8750 will facilitate future studies involving positional cloning and marker-assisted selection in breeding.Twenty-one stable QTL related to PH, SL, and SCN were identified. These stable QTL and the user-friendly marker The online version contains supplementary material available at 10.1186/s12870-022-03968-0. Triticum aestivum L.) is one of the most important crop worldwide and provides approximately 20% of the calories in the humans diet [Common wheat  has result in several new cultivars that, were not prone to lodging under increased fertilizer application, thereby successfully achieving increased yield [Rht-B1b and Rht-D1b also decreased KNS and TKW while reduce PH [PH is closely associated with lodging resistance and grain yield in wheat . The apped yield . Howevereduce PH . To dateeduce PH . TherefoRht genes distributed on 11 wheat chromosomes have been identified and formally named [Rht-B1b, Rht-D1b, Rht8, Rht13 and Rht24 were widely used in modern cultivars [Rht genes regulating PH have been cloned in wheat. Among them, Rht12 encodes a gibberellin (GA) 2-β-dioxygenase [Rht23 likely encodes an AP2 transcription factor [Rht24b encodes a GA 2-oxidase [Rht8 encodes a ribonuclease H-like protein [TaDEP1 [TaCOLD1 [TaTB1 [TaARF12 [QTL mapping is an efficient strategy for detecting QTL and genes for PH . Twenty-ly named . Rht-B1bultivars , 13–14. xygenase , Rht23 ln factor , Rht24b -oxidase , and Rht protein , 19. Add [TaDEP1 , TaCOLD1[TaCOLD1 , TaTB1 [1 [TaTB1 , 22, andQ encodes AP2 domain transcription factor, which interact with miRNA172 to regulate brittle spike, SL, SCN, and grain shattering [Rht24b, Rht8, and TaARF12 have multiple functions and could regulate PH and SL [QSpl.nau-2D, a major QTL for SL on chromosome 2D, was found to affect SL, SCN, and TKW [SL and SCN are important spike morphology traits closely related to KNS and TKW in wheat . To dateattering . Rht24b,H and SL , 23. ManH and SL , 28, 29. and TKW , 31. SinThe wheat germplasm PuBing 3228 (P3228), which has superior features such as large spikes, was widely used in the main growing areas of winter wheat of China. Gao 8901 (G8901) is a commercial cultivar in Yellow and Huai River valley winter wheat region of China with a shorter PH and medium size spike when comparing with P3228. Here, we aimed to (i) identify QTL for PH, SL, and SCN using a RIL population derived from ‘P3228 × G8901’ (PG-RIL); (ii) reveal the effect of SL to PH and to SCN, respectively, using conditional QTL analysis; (iii) detect QTL clusters or pleiotropic loci associated with those traits and (iv) develop a Kompetitive Allele Specific PCR (KASP) marker for stable QTL to be used in marker-assisted selection (MAS) in wheat breeding.The 176 RIL population and the two parents were planted in four environments. The two parents P3228 and G8901 had significant differences in PH, SL, and SCN. Compared with G8901, P3228 had a taller PH and longer SL but a lower SCN  ranged from 9.98% to 17.04%  in the Nanda2419 × Wangshuibai RIL population [HL2 can increase the SL and KNS, and decrease SCN and, that is a favored morphological trait for Fusarium head blight resistance and beneficial to wheat breeding [QPh.cas-2B.2, QPh.cas-4B.1 and QPh.cas-6B.3 mapped only one environment coincided with the documented QPH.caas-2BL.1, QPH.caas-4BL and QPH.caas-6BL in the Doumai × Shi 4185 RIL population, respectively, reflecting highly reliable QTL identification in our study. [QPh.cas-1A and QPh.cas-6A were likely novel stable QTL for PH identified in the present study.In the current study, we identified 21 QTL for PH that, five stable QTL were mainly distributed on chromosomes 1A, 5A, 6A and 7D Table . Comparer study. . Due to QSl.cas-6B.2 and QScn.cas-6B were located in the interval AX-108874447–AX-108763535  reference population, respectively [QSl.cas-2D.2 in the interval AX-110462142–AX-110168677 on chromosome 2D has also been reported in a previous study [QSl.cas-2B.2, QSl.cas-4A.1 and QSl.cas-6D.2 were likely novel QTL for SL.Six stable QTL for SL were identified and, located on chromosomes 2B, 2D, 4A, and 6B Table . The stakgrounds . Notablypulation . These rectively . The QTLus study . NotablyQScn.cas-2B.2 overlapped with QSC.cib-CK1-2B and QSd.sicau-2B.2 [QScn.cas-6A.1 overlapped with QSC.cib-CK1-6A from the Chuanmai42 × Kechengmai1 RIL population [QScn.cas-6A.1 was located in the same QTL cluster as QTkw.cas-6A.1 and QKw.cas-6A in the PG-RIL population, which might be the major focus for breeding selection [QScn.cas-5D coincided with QSC.cib-CC-5D from the Chuanmai42 × Chuannong16 RIL population [QScn.cas-3D.1, QScn.cas-6A.2 and QScn.cas-7A were likely novel stable QTL for SCN. Based on the above results, the stable QTL detected in multi-genetic background should be important selection locus in wheat breeding. Of course, the new QTL with accurate locations detected in our study need to be further verified for their genetic effects and further used in molecular assisted breeding.Ten stable QTL for SCN were identified on chromosomes 2B, 3D, 4D, 5D, 6B, 6D, and 7A , a basic helix–loop–helix transcription factor, was located in this interval. Several studies showed that loss-of-function Talax1 mutations confer compact spikes [QScn.cas-4D.1 was mapped to the 466.62–476.32 Mb interval on chromosome 4DL according to the Chinese Spring reference genome v1.0 [SVP3-4D (TraesCS4D02G301100) was located in 469.304–469.319 Mb on 4DL. SVP3-4D is an important gene regulating flowering as well as wheat spike, spikelet development, and PH [QScn.cas-6D.2 in the interval AX-111694627–AX-109997558, was mapped to 291.14–301.71 Mb on chromosome 6D. A gene TaPRR1-D1 (TraesCS6D02G207100) was located in this interval. TaPRR1-D1 is a circadian clock gene regulating heading date, PH and TKW [The release of the hexaploid wheat reference genome has significantly accelerated the cloning of important QTL candidate genes ,43,44. It spikes . The staome v1.0 . The gen, and PH . The staRht8 and Rht25 both regulate PH and SL [qPH-6B for PH was not affected by SL [QPh.cas-5A.4 and QPh.cas-6A were mainly contributed by SL, while QPh.cas-5A.3 was independent of SL , 1D (1), 2A (1), 2B (1), 6B (1) and 7D (2) using conditional QTL analysis Table . Fourtee, 1D (1),SL Table . In concKASP8750 linked to the stable QTL QPh.cas-5A.3 was developed and verified in PG-RIL and a natural population. Recent studies show that Rht8 and Rht24b have no significant negative effect on yield while reducing PH, and these dwarf genotypes have been widely used by breeders in wheat breeding [KASP8750-T allele decreased PH but did not affect SL or KNS in either PG-RIL or a natural population , long SL (mean 10.58 cm), and low SCN (mean 2.20), whereas G8901 is a commercial cultivar with a short PH (mean 83.66 cm), short SL (mean 8.22 cm), and high SCN (mean 2.68)  of the tallest culms for each plot. SL was measured from the first rachis node to the top of the uppermost spikelet excluding the awns. SCN was calculated by dividing the number of spikelets per spike by the SL.A combined analysis of variance, mean values, standard deviations, and covariance of variation (CVs) was performed over environments for three traits were computed with SPSS Statistics v20.0 software . Transgressive segregants were identified using least significant difference test. For each trait, the best linear unbiased predictor mean (BLUP) was calculated using the mixed linear model with the fitting of both line and environment as random effects in the lme4 package . Correlag, the number of environments is equal to e, and the number of blocks is equal to r. Assuming yijk is the oberservation of the Ith genotype in the kth block in the jth environment. Multiple comparison tests were conducted for genotypic means in each environment by the least significance difference (LSD). Broad-sense heritability (H2) was calculated using the following formula H2 = VG/VP; where VG and VP are the genetic variance and phenotypic variance, respectively.For the combined ANOVA for each trait, we assume the number of genotypes is equal to http://www.biometris.nl/uk/Software/MapChart/) was used to construct the genetic map. The QTLs were named based on McIntosh et al. [http://202.194.139.32/blast/viroblast.php) was performed to align the QTL-associated flanking SNP marker sequences with the Chinese Spring reference genome v1.0 [A high-density bin map has been constructed in our previous study . QTL anah et al. , where ‘ome v1.0 .(PH|SL)) of PH and (y(SCN|SL)) of SCN in wheat were obtained by the mixed-model approach. The conditional phenotypic value can be divided into y(SCN|SL) = μ(SCN|SL) + G(SCN|SL) + E(SCN|SL) + e(SCN|SL), Conditional phenotypic values y(SCN|SL) suggest the value of SCN without the influences of SL; μ(SCN|SL) is the conditional population mean; G(SCN|SL) is the conditional general genotypic effect; E(SCN|SL) is the conditional effect for the environment; and e(SCN|SL) is the conditional residual error. y(SCN|SL) and y(PH|SL) was obtained from each environment . Conditional QTL analysis was performed to analyse the genetic contributions of SL to SCN in QTL IciMapping v4.1.Conditional genetic analysis was conducted based on the phenotypic values of PH conditioned on SL and SCN conditioned on SL, which were obtained by the method described by Zhu . The conThe KASP markers were designed based on the identified SNPs obtained from the Affymetrix wheat 660 K SNP array , and werAdditional file 1:Supplementary file 1.Additional file 2: Supplementary file 2.


The partial replacement of the mineral components of concrete with natural renewable analogues in full possession of the performance characteristics of the final material, allows not only the concrete-production process to be made more environmentally friendly and inexpensive, but also to solve an important task for the agricultural industry, which is that associated with waste disposal. The scientific novelty of the work is in the obtaining of new concrete compositions by the partial replacement of coarse aggregate with a natural analogue in the form of a walnut shell, which has the maximum ratio of the strength of the composite to its density, as well as in identifying new dependencies of strength and density and their ratio on the amount of replacement of mineral coarse-aggregate walnut shell. The main goal of this article was to analyze the effect of composition factors on characteristics of concrete with partial replacement of large aggregates with walnut shells and to search for the optimal compound that would make it possible to obtain concrete with a minimum decrease in strength characteristics with a maximum decrease in concrete density. Cubes and prism laboratory samples were made from concrete of normal density with the replacement of coarse aggregate by 5, 10, 15, 20, 25 and 30%, by volume. The main mechanical properties, such as density, strength  of the concrete samples were studied. The investigation used standard methods and scanning electron microscopy. An increase into strength characteristics up to 3.5%, as well as the maximum ratio of strength to density of concrete, was observed at a walnut-shell dosage of 5%. Effective partial replacement of coarse aggregate with walnut shells leads to a reduction in the consumption of crushed stone by up to 10% and a decrease in the mass of concrete by up to 6%. The growth in global-construction volume is directly related to the growth in the production of building structures and, as a result, to the growing demand for building materials . ConcretIn addition, in the agricultural industry there are a number of problems associated with the disposal of waste from production processes, the volume of which is growing every day ,5. The pOne of the main candidates for replacing coarse aggregate in concrete is machined walnut shells. The walnut shell is a byproduct of the production of shelled walnuts, produced on a huge scale and sold all over the world. The fruit of the walnut is a pseudo-monomeric drupe-type nut. The lignified endocarp is a strong spherical or ovoid bone with several (from two to five) incomplete partitions, inside of which there is an edible seed. It is enclosed in a fibrous mesocarp, topped with a leathery exocarp. When ripe, the peel of the fruit dries up and bursts into two parts, separating from the stone, which does not open by itself ,17,18. TAlmost all walnut-processing enterprises experience difficulties with the sale and disposal of the shell. Along with this, the walnut shell has a sufficiently high strength, does not rot, practically does not lose its properties over time, quickly renews in nature and is an environmentally friendly and safe product for humans and animals . The harTo create the most massive need for walnut shells, which could allow large-scale and environmentally safe disposal of its entire volume, is possible only by integrating the recycling process into large and fundamental industrial sectors. The most important candidate for this is the construction industry and the production of building structures . The walIn order to use the walnut shell as a coarse aggregate in concrete, it is first necessary to subject it to mechanical and chemical treatment. It is necessary not only to crush it to a fraction of the required size modulus, but also to keep the resulting material in hot water to extract water-soluble sugars, which can adversely affect the cement-hydration process. For these purposes, soaking quicklime in solution is also used, but it requires more time and additional costs for quicklime, which makes this method less effective ,18,21,22Analyzing the process of processing walnut shells to obtain organic coarse aggregate for concrete, we can conclude that, despite the use of water in it and taking into account the potential energy costs for its heating, it is much more environmentally friendly and less energy-intensive than the production of a mineral coarse-aggregate placeholder. It is also important to note that, as mentioned above, the walnut shell is a rapidly renewable natural raw material for which the issue of mass disposal has not been resolved, while mineral aggregates are exhaustible and non-renewable resources that require energy-intensive and environmentally unsafe technological processes for production ,26,27,28The study  was devoIn , the autThe study presented in this article develops the ideas of the concept of sustainable environmentally friendly concrete, which implies the partial and complete replacement of the mineral components of concrete with natural and rapidly renewable analogues. Replacing large-mineral aggregate with walnut shells will partially eliminate complex mechanized and energy-intensive production processes associated with high greenhouse-gas emissions ,40,41,42Therefore, the main goal of the work was to study the effect of partial replacement of coarse mineral aggregate with mechanically processed and prepared-for-use walnut shells on the structure and characteristics of concrete and the selection of the optimal amount of walnut shells, which would make it possible to obtain an environmentally friendly building material with the highest ratio of strength to density.Raw materials such as Portland cement, crushed stone, and sand and walnut shells were used to make concrete samples. The main physical and mechanical characteristics of raw materials are presented in 3S, 15% of C2S, 7% of C3A and 11% of C4AF.The mineral content of Portland cement is as follows: 67% of CThe walnut shell underwent the necessary mechanical processing to achieve a grain size of 5 to 20 mm, and was purified from water-soluble sugars. Shell cleaning was carried out in water at a temperature of 60 °C, in which it was kept for 24 h for better extraction of water-soluble sugars. Then, the water with dissolved sugars was drained and the walnut shell was dried in an oven at a temperature of 50–55 °C. The content of the fraction from 5 mm to 10 mm was 70.4%. A photograph of a walnut shell is shown in The production of concrete samples was carried out in laboratory conditions using concrete of normal density class B30 (CS ranging from 37.5 MPa to 50 MPa), according to GOST 26633-2015 . The conMixing of concrete components was carried out using a BL-10 laboratory concrete mixer . Vibration of the concrete of the samples during their manufacture was carried out on the vibrating platform SMZh-539-220A , and the vibration time was 60 s. Testing of prototypes was carried out using the following equipment: testing machine P-50 , tensile testing machine R-50 .The walnut shell was crushed on the ShchD-6 jaw crusher manufactured by Vibrotechnik . Grains less than 5 mm and more than 20 mm were screened out using a set of sieves for coarse aggregate with mesh sizes of 5, 10 and 20 mm, manufactured by Vibrotekhnik . The walnut shell was dried in an oven SNOL 67/350 .The production of the concrete mixture, molding, demolding and hardening of the samples were carried out according to the method already described by the authors earlier in the work . The walThe microstructure of the samples was analyzed using a ZEISS CrossBeam 340 electron microscope (Carl Zeiss Microscopy GmbH (Factory), Jena, Germany), as in . Seven sThus, for the compression test, 42 cubes were made (6 cubes for each mixture), for axial compression—21 prisms (3 prisms each), for bending—21 prisms (3 prisms each), and for axial tension—21 prisms (3 prisms each).The purpose of axial CS test is to correct and verify the CS. As a rule, cubic strength is a standardized normative concept that characterizes the class of concrete as a building material. However, a number of normative and technical sources in the territory of the CIS countries and some countries of Eurasia also recommend the use of an additional indicator, “axial compressive strength”, if it is necessary, to calculate reinforced-concrete structures and determine precisely the structural characteristics of concrete.Rb.cub—compressive strength determined on concrete cube samples; ρ—density of concrete samples.The indicator characterizing the ratio of the CS of concrete to its density, called the coefficient of constructive quality (CCQ), was calculated by the formula:Graphs in R2The dependencies presented in Discussing the resulting graphs in Changes in the characteristics of concrete depending on the amount of mineral coarse aggregate replaced by walnut shell are shown in According to the test results presented in However, a further increase in the percentage of replacement of coarse aggregate with a vegetable analogue led to a decrease in SC. This trend is due to the fact that the properties of the walnut shell are closer to coarse aggregates for lightweight concrete and the partial replacement of the mineral aggregate in heavy concrete with walnut shell will inevitably lead to a certain degree of reduction in SC, which is in good agreement with the works ,22,25,29The best value for the CCQ is for concrete with a walnut-shell content of 5%, and the CCQ values for concrete with the control composition and with 10% walnut-shell content are approximately equivalent. The dependence of CCQ on the WS content is well approximated by a polynomial of the third degree, and is shown in Equation (7) with a determination coefficientThe analysis of the results of experimental studies of the characteristics of concrete samples with the partial replacement of crushed stone with walnut shells, including plotted-graphical dependencies and data on the effect of the amount of coarse aggregate from walnut shells in concrete on its physical and mechanical characteristics, as well a comparison of the results obtained with the results obtained on the control composition, found that not only the presence of organic coarse aggregate, but also its quantity in relation to the volume of coarse mineral aggregate, significantly affected the characteristics of concrete. It was found that the optimal amount for replacing dense aggregate with walnut shells is 5%, which roughly coincides with ,28, wherFor the study of the microstructure, samples of hardened cement paste were selected at the boundaries of the contact zones with coarse aggregate. However, with a rational dosage, the replacement of a part of the mineral coarse aggregate with an organic one positively affects the SC of the composite (5%) or leads to a slight decrease (10%), while reducing the weight of the final composite material. Thus, the addition of walnut shells to concrete as an alternative to coarse mineral aggregate is acceptable to lighten the weight of concrete and reinforced concrete structures and to dispose of waste in the form of walnut shells.The results obtained during the study are important for construction practice, but they need to be explained and discussed according to the scientific fundamental principle of a composition-structure characteristics. Thus, in the course of the experiment, increments, or the preservation of the values of the CCQ at the proper level, were established, due to the fact that the study analyzed lightweight concretes, that is, those having a reduced mass, and thereby expanded their universal operational ability.Let us analyze the obtained results in the context of scientific justification. Due to the fact that the walnut shell has an advantageous rough surface which is similar to that of low-density crushed stone, and, in principle, by its very nature is similar to the interaction inside concrete of those concrete components with lightweight aggregates, such a walnut and its shell can be compared to these aggregates. The increased roughness and angularity of some forms allow them to achieve better adhesion of such an aggregate with hardened cement paste. This provides better structure formation and improves the formation of the composite at the stage of hardening, which ultimately leads to a more perfect structure and a sufficiently high mechanical strength inherent in such lightweight concretes. It is the rational ratio of strength and density properties in such concretes that ensures the creation of a high CCQ. This is confirmed not only by experimental tests, but also by microscopic studies using the method of scanning electron microscopy. Thus, the applied CCQ is confirmed by the fundamental principle of a better structure, from which high-performance properties follow, and all this is initially justified by a rational choice of composition. Of course, an inefficient dosage of walnut shells can lead to a deterioration in mechanical properties and structure in the cases below. With an excessive dosage of walnut shells, due to its roughness, the need for additional wetting of the surface of such a filler will occur, which will lead to excessive water consumption. Such a factor will lead to a deterioration in the structure and, accordingly, the properties of concrete. If we assume the insufficient introduction of walnut shell in an amount less than rational, then this may lead to the under-formation of the proper structure in terms of a deterioration in operational properties, that is, an unreasonable increase in the weight of the structure and a discrepancy between its operational density in relation to its strength. Thus, in order to achieve an effective balance between structural perfection and operational properties, one should strictly adhere to the experimentally established rational dosage of walnut shells used as aggregate for lightweight concrete, with an increased CCQ. This is in good agreement with the works ,27,28.In , variousAnalyzing the above, we can conclude that the characteristics of the walnut shell make it possible to use it as a partial replacement for the mineral coarse aggregate of light and heavy concrete for the production of concrete and reinforced-concrete structures, small architectural forms, and elements of decoration, decor and landscaping. For the construction industry, this would significantly reduce the cost of concrete, as well as from avoid a number of processes that pollute the environment, while almost completely preserving the strength and physical and mechanical characteristics of concrete. From the point of view of the agricultural industry, this would allow for the mass environmentally friendly, efficient and sustainable disposal of large volumes of waste. This also corresponds to the idea of introducing environmentally friendly “green” technologies into production processes, which provide for waste-free production and the use of natural, environmentally friendly, completely renewable materials that are safe for humans and animals. Thus, the presented work is both of an applied technological nature and opens up prospects for further research in the field of economic efficiency and ecology.Based on the study, the following conclusions were made.(1)In the course of the study, the main parameters and characteristics of the organic large-walnut-shell aggregate used to partially replace the mineral components of the concrete mixture, were determined.(2)According to the results of the experiments, the dependences of the physical and mechanical characteristics of concrete on the amount of added walnut shell and the microstructure of the composite, were established. Improving the properties of concrete, due to the partial replacement of coarse mineral aggregate with a vegetable analogue from walnut shells, is expressed in a decrease in its weight and an increase in the CCQ. The maximum increase in strength parameters for concrete with 5% replacement of a part of the mineral coarse aggregate was: for cubic CS—2.7%, for axial CS—3.3%, for TS in bending—3.4%, and for axial TS—3.3%. The maximum decrease in the weight of concrete, at which a decrease in SC of no more than 10% was observed, reached 6%.(3)The optimal percentage for the replacement of mineral coarse aggregate with walnut shell was in the range of 5% to 10%. Increasing the CCQ in this case amounted to 6%.(4)An increase in the dosage of walnut shells from more than 10% to 30% leads to a decrease in SC of up to 45%, in weight of up to 17% and in CCQ of up to 37%.(5)The study of the resulting composition using electron-microscopy methods showed that the resulting concrete composition is effective both in terms of the characteristics of the hardened composite and in terms of its economic and environmental efficiency, compared to the control composition of concrete without the introduction of walnut shells.The significant advantage of the proposed composition of concrete for economics and ecology, while maintaining its overall strength compared to conventional concrete, will open up broad prospects for further research and practical application. The presented work has an applied technological character and also opens up prospects for further research in the fields of economic efficiency and ecology.


In order to explore the damage and mechanical properties of ballastless track after a fire, the uniaxial compressive strength, shear strength, peak strain, and elastic modulus changes due to temperature were obtained through uniaxial compressive and shear tests of concrete after exposure to high temperatures. The test results showed that with increases in temperature, the uniaxial compressive strength, shear strength, and elastic modulus of concrete all presented a decreasing trend, while the peak strain had an increasing trend. Then, based on the classical damage theory model and the strength probability distribution function of concrete micro-units, the high-temperature damage constitutive equation for concrete was established, and the compressive stress–strain curve of concrete after exposure to high temperature was reproduced. Finally, using the CFD numerical simulation software, the temperature field of a ballastless track structure in a tunnel during a fire was obtained, and the temperatures at different positions of ballastless track bed were acquired. Combined with the high-temperature damage constitutive equation for concrete deduced from tests and theoretical analysis, the strength and damage values of the ballastless track bed at different positions after a tunnel fire were obtained. Concrete is one of the most important building materials, and its mechanical properties are an important factor in determining its service performance. After exposure to a high-temperature environment, the mechanical properties of concrete are very different from those at normal temperatures ,2,3,4. TIn recent years, tunnel fire accidents have occurred frequently, often causing serious casualties and property losses. Tunnel fire research ,19,20,21These studies have not only greatly deepened the understanding of the damage and mechanical properties of concrete after exposure to high temperatures but have also achieved fruitful work on smoke flow and temperature fields of tunnel fires. However, there is still a lack of targeted research on the temperature field distribution of the ballastless track and the damage and mechanical properties of the concrete track bed in a tunnel after a fire. Therefore, this paper carried out tests of the mechanical properties of concrete after exposure to high temperatures. Starting from the classical damage theory model and the strength probability distribution function of concrete micro-units, the high-temperature damage constitutive equation for concrete was established. Then, the temperature field of the ballastless track structure in a tunnel during a fire was simulated using the computational fluid dynamics (CFD) numerical software FLUENT, and finally the damage and mechanical properties of a ballastless track structure in a tunnel after a fire were obtained.The materials and mix properties used in preparing the concrete related to the experimental part of this paper were as shown in The concrete was made into a cube specimen of 150 mm × 150 mm × 150 mm and cured in a standard curing room for 28 days after demolding. Before the mechanical properties were tested, a resistive heating furnace (model: KSY-12-T), produced by Changsha Changcheng Electric Furnace Factory, was used to heat the concrete specimens , as showCompressive strength and shear strength are important indicators to measure the mechanical properties of concrete, which are greatly affected by temperature. In order to study the influence on the mechanical properties of concrete after exposure to high temperatures, uniaxial compressive and shear tests were carried out on the heated specimens at 20 °C, 100 °C, 200 °C, 400 °C, 600 °C, and 800 °C. The compression test used a uniaxial compression form; the location of strain gauges is shown in In order to obtain a more accurate stress–strain curve, during the experiment the instrument could automatically record the force and displacement, and then divide the force by the loading area to obtain the stress and divide the displacement by the height to obtain the strain. The converted curve is the stress–strain curve, and the stress–strain curves of concrete specimens after different heated temperatures are shown in m equals 1, while the descending segment after ε/εm equals 1 has greater discreteness and has varying degrees of smoothness.In this paper, the stress–strain curves after different heated temperatures were normalized without dimensionality , that isAt the same time, in order to quantitatively describe the relationship between elastic modulus and temperature, on the basis of obtaining the full stress–strain curve, stress and the corresponding strain at the ordinate of 0.4 on the full stress–strain curve were taken. Finally, the elastic modulus of the concrete specimens after different heated temperatures were obtained by dividing the strain by the stress obtained through the above method , as showThere are two limitations on the use of this formula: first, the type of concrete was ordinary concrete, and the concrete strength grade was C35; second, the test type was a uniaxial compression test.There are two limitations on the use of this formula: first, the type of concrete was ordinary concrete, and the concrete strength grade was C35; second, the test type was a uniaxial compression test.(1)Damage calculation using “residual strength” thermal damage modelThis paper uses two ways to evaluate the damage of concrete:cf0 is the uniaxial compressive strength of concrete at room temperature, fc0 = 36.15 MPa, and D1(T) is the damage value. The damage value D1(T) calculated by Formula (4) is shown in Luo et al.  studied (2)Damage calculation using elastic modulusD2(T) of concrete structure based on elastic modulus, as shown in Formula (5). In combination with Formula (1), the damage Formula (6) can be obtained.TE is the elastic modulus of concrete after high-temperature heating, and E0 is the initial modulus of concrete at room temperature, E0 = 3.23 × 104 MPa.Jiang et al.  determinSimilarly, the damage value calculated by Formula (6) is shown in The damage to concrete is caused by the initiation, expansion, and connection of its internal cracks; both temperature loads and external forces may cause the generation of internal cracks, which constitute damage. Based on the classical damage theory model and the strength probability distribution function of concrete micro-units, an equation describing the whole process of concrete compressive damage at high temperature is obtained in this paper.D is the damage value, and Taking the representative concrete volume unit used in the research and based on Lemaitre’s hypothesis of “equivalent strain”, the Formula (7) based on concrete damage mechanics can be obtained :(7)σ=E0(TK is introduced as shown in Formula (8):TK is the temperature softening factor; cf(T) is the uniaxial compressive strength of concrete at high temperature, as shown in Formula (2); cf0 is the uniaxial compressive strength of concrete at room temperature, and cf0 = 36.15 MPa.After the concrete was heated to high temperature, its mechanical properties weakened, and the stress–strain curves transitioned from sharp to flat, indicating that peak stress, uniaxial compressive strength, and elastic modulus decreased while peak strain increased. For this reason, the temperature-softening factor Therefore, when the influence of temperature is considered, the high-temperature damage constitutive equation for concrete can be described as follows :(9)σ=E0 :(10)φ(ε)The damage process of concrete can be divided into yield damage and fracture damage. When describing the damage evolution of concrete, the probability density of damage and fracture obey a three-parameter Weibull distribution, and the probability density of yield damage and fracture damage obedience is consistent. The formula is listed as follows :(11)φ(ε)Combining Formulas (10) and (11), the expression of damage value D is shown in the following :(12)D=∫0A is added before the right side of the equal sign of Formula (13), so Formula (14) can be obtained by combining Formulas (2), (8), (9), and (13):In addition, in order to improve the accuracy of fitting, the corresponding coefficient Through the regression and analysis of the test data, the values of A, It can be seen from Shear strength is the basic mechanical property of concrete. In this paper, a shear test was carried out on concrete after being heated to a high temperature, and the test results are shown in In addition, in order to express the relationship between shear strength and the temperature of the concrete, MATLAB was used to fit the data. The fitting Formula (16) was obtained, and the fitting results are shown in It can be seen from During a fire, different positions of a ballastless track structure in a tunnel will have different temperatures. In order to obtain the temperature field, the CFD numerical simulation software FLUENT was used.3 in size, and the carriages were 1 m apart [A numerical model was built. The total length of the tunnel was 100 m, the thickness and the inner diameter of the tunnel lining were 0.3 m and 4.9 m, respectively, and there were 7 carriages, each of which was 12 × 3 × 4 m m apart . The sub m apart . Figure 3, the specific heat capacity was 1100 J/(kg·K), and the thermal conductivity was 1.2 W/(m·k) [In this model, the grid size was 0.1 m × 0.1 m × 0.1 m within 20 m before and after the fire source, and the grid size was 0.4 m × 0.1 m × 0.1 m at other locations. It was assumed that in the initial state before the fire, the temperature of each element inside and outside the model was the same and equal to the temperature of the external environment, and the initial air pressure was a standard atmospheric pressure. In the model, the inlet boundary condition was the velocity inlet boundary, the outlet boundary condition was the pressure outlet boundary, the wind speed was set as 2 m/s, the heated boundary had heat convection and heat radiation, and the non-heated boundary only had heat radiation. In addition, the density of the concrete material was 2400 kg/m W/(m·k) , and thi W/(m·k) . It was The temperature cloud of the tunnel vault along the longitudinal direction is shown in The overall temperature of the concrete track bed is shown in In addition, the overall temperature field of the cast-in-place C35 concrete track bed was symmetrical with respect to the X axis (width) of the track bed, so half of it was taken for study in the following. The temperature distribution at different positions in the track bed are shown in Combined with 1D(T) and 2D(T) at the surface, middle, and bottom of the track bed were 0.63 and 0.79, respectively. The higher the temperature, the lower the uniaxial compressive strength, shear strength, and elastic modulus, while the greater the damage value. Therefore, according to the high-temperature damage constitutive equation for concrete and the temperature field of the track bed, the strength and damage of the track bed at different positions after a tunnel fire can be accurately obtained, which can provide a theoretical basis for post-disaster assessment and reinforcement of the track structure.It can be seen from ▪Taking 20 °C as the benchmark, when the temperature reaches 100 °C, 200 °C, 400 °C, 600 °C, or 800 °C, the uniaxial compressive strength, elastic modulus, peak strain, and shear strength of concrete changes after the increase in temperature as follows: the uniaxial compressive strength decreases by 34.00%, 36.85%, 49.68%, 71.09%, or 79.70%, respectively; the elastic modulus decreases by 43.03%, 46.44%, 71.21%, 81.42%, or 91.95%, respectively; the peak strain increases by 44.17%, 112.27%, 223.31%, 357.67%, or 479.75%, respectively; and the shear strength decreases by 2.52%, increases by 9.86%, or decreases by 35.78%, 53.90%, or 62.61%, respectively.▪Based on the mechanical testing of concrete after exposure to high temperatures, the high-temperature damage constitutive equation for concrete was established, and the stress–strain curves of concrete under uniaxial compressive after exposure to high temperatures were accurately simulated.▪FLUENT was used to simulate the temperature field of the cast-in-place C35 concrete track bed when a fire occurs in a tunnel. The surface of the track bed near the fire carriage had the highest temperature. Combined with the high-temperature damage constitutive equation for concrete and the formula for damage fitting, the strength and damage values of the track bed slab at different positions after a tunnel fire can be obtained quickly and accurately, which can provide a theoretical basis for post-disaster assessment and reinforcement of the track structure.