Waste foundry sand (WFS) is the by-product of the foundry industry. Utilizing it in the construction industry will protect the environment and its natural resources, and enable sustainable construction. WFS was employed in this research as a fractional substitution of natural sand by 0%, 10%, 20%, 30%, and 40% in concrete. Several tests, including workability, compressive strength (CS), splitting tensile strength (STS), and flexural strength (FS), ultrasonic pulse velocity (USPV), Schmidt rebound hammer number (RHN), and residual compressive strengths (RCS) tests were performed to understand the behavior of concrete before and after exposure to elevated temperatures. Test findings showed that the strength characteristics were increased by including WFS at all the phases. For a substitute rate of 30%, the maximum compressive, splitting tensile, and flexural strength were observed. Replacement with WFS enhanced the 28-day compressive, splitting tensile, and flexural strength by 7.82%, 9.87%, and 10.35%, respectively at a 30% replacement level, and showed continuous improvement until the age of 91 days. The RCS of foundry sand concrete after one month of air cooling at ambient temperature after exposing to 300 °C, 400 °C, 500 °C, 600 °C, 700 °C, and 800 °C was found to be in the range of 67.50% to 71.00%, 57.50% to 61.50%, 49.00% to 51.50%, 38% to 41%, 31% to 35% and 26% to 31.5% of unheated compressive strength values for 0% to 40% replacement of WFS, respectively. The RCS decreases with increasing temperature; however, with increasing WFS, the RCS was enhanced in comparison to the control samples. In addition, the replacement of 30% yielded excellent outcomes. Hence, this study provides a sustainable construction material that will preserve the Earth’s natural resources and provide a best use of WFS. The construction industry plays a vital role in the economic development of any country. Concrete can be classified as the most abundantly used material of the construction industry. The only material used more than concrete by man is water . Current6 tons of foundry sand is used in production in a year; out of this amount, about four to seven million tons are wasted per annum and offered for recycled use [Foundry sand is a molding sand that is used by the foundry industry owing to its easy accessibility, low cost, heat damage resistance, and bonding with other binders and organic materials. This sand is quite higher in quality than natural sand. Foundry industries utilize this sand time and again. When this sand remains no longer able to be used further in foundry industries, then it is removed and termed as waste foundry sand (WFS). Waste foundry sand is also referred to as used foundry sand (UFS) or spent foundry sand (SFS) . Fine pacled use ,9.Numerous researchers investigated the use of used foundry sand in various civil engineering applications such as highway applications , controlSiddique et al. ,14 evaluIn the previous study, Khatib et al.  substituCompressive, splitting tensile strengths and flexural strengths tests were measured at the ages of 7, 28, 56, 91, and 365 days, and noticed an incremental trend of up to 15% replacement level for mutual (M20 and M30) grades of concrete. Ultrasonic pulse velocity (USPV) tests were evaluated at 28, 91, and 365 days of age. Ultrasonic pulse velocity (USPV) values also exhibited increment in values, with an increment in replacement level up to 15%. Singh and Siddique et al. ,18 evaluThe residual strength of hardened concrete after fire when it cools down changes depending upon the maximum temperature attained, mix proportion, aggregate type, fire exposure intensity, and duration of fire ,29,30. GChang et al.  used conThe already published literature such as Bhardwaj et al. , BradshaOrdinary Portland cement  was provided by the Fauji cement company in Pakistan with the chemical composition and physical properties complying with the standard specification of ASTM C-150 . The cheSieve analysis of WFS and natural fine aggregate (NFA) was carried out to observe the particle size distribution pattern of WFS and NFA. The sieve analysis evaluation of WFS and normal sand showed that the WFS is a finer material than NFA. The sieve analysis pattern of WFS and NFA is presented in Sieve analysis of coarse aggregate was carried out to observe the particle size distribution pattern of coarse aggregate. The sieve analysis pattern of coarse aggregate is presented in Five mixtures incorporating WFS as a fractional substitution of natural sand were prepared. Normal sand was substituted by WFS by weight. The proportion of replacement ranged from 0% to 40% at the accretion of 10%. The mix proportions to be used are provided in Wet/fresh state characteristics of concrete such as slump and compacting factor tests have been idenfied according to ASTM C143/143M  and BS 1The mean net value of three specimens was used for all the calculations at all the ages and replacement levels. All the samples were casted at ambient temperature. Casted samples were protected with plastic sheets and left in a molding yard for 24 h at ambient temperature, and then demolded and kept in water for the required age of curing and test. Compressive strengths, splitting tensile, and flexural strengths tests were performed as per ASTM standards C39/C39M , C496/C4(i)After the completion of standard curing (28 days) the samples were carried out from the curing tank and then dried at ambient temperature for seven days.(ii)The USPV test was conducted at the seventh day after the completion of standard curing.(iii)After that, the samples were then exposed to elevated temperatures of 300, 400, 500, 600, 700, 800, 900, and 1000 °C for one-hour at peak temperature level.(iv)After being exposed to elevated temperatures, the samples were placed in surrounding air/open to sky environment for 30 days.(v)A USPV test was conducted again at the 30th day after being exposed to the surrounding air/open to sky environment.The USPV test mostly involves measuring the electronic wave velocity passing through the concrete specimen, which is used to diagnose the quality of concrete. A USPV test for concrete incorporating WFS as a partial substitute of sand was measured in the way discussed bleow.The ultrasonic pulse velocity of the concrete samples were measured by implementing the technique specified in BS EN 12504-4:2004 [(i)After the completion of standard curing (28 days), the samples were carried out from the curing tank and then dried at ambient temperature (25 °C) for seven days.(ii)The RHN test was conducted on the seventh day after completion of standard curing.(iii)After that, the samples were then exposed to elevated temperatures of 300, 400, 500, 600, 700, 800, 900, and 1000 °C for 1 h at a peak temperature level.(iv)After being exposed to elevated temperatures, the samples were placed in the surrouding air/open-sky environment for 30 days.(v)An RHN test was conducted again at the 30th day after being exposed to the surrounding air/open-sky environment.The test of the rebound hammer number (RHN) is appropriate for both the laboratory and the field. The surface smoothness influences the rebound number. An RHN test for concrete incorporating WFS as a partial substitute of sand was measured in the way discussed bleow.The rebound hammer test was performed by implementing the techniques specified in BS EN 12504-4:2004 .After completing the period of 28 days of standard curing/watering, the entirely cured samples were picked out from the curing tank and dried out at ambient temperature for seven days. The concrete specimens (cylinders of 150 × 300 mm size) were fired/heated in an electric furnace for the temperature levels of 300, 400, 500, 600, 700, 800, 900, and 1000 °C at a mean rate of 4.5 °C/min. The level of temperature/hotness was increased in accordance with the fire curve of ISO-834-12 . The higWet concrete workability is the combination of composite properties that contains the necessities of ease in compaction, mobility, finishibility, and placeability. Slump is the indicative measurement of consistency or workability of concrete. The compacting factor is also in correspondance with the slump values. The slump value was noted to decrease with the incorporation of WFS because of the finer particles present in foundry sand. Water demand escalated with the escalating percentage substitution of foundry sand. Beyond 30% replacement, water demand increased in order to achieve the desired workability. As observed, the slump values decreased with the increase in replacement level. This might be due to the void-filling act of the WFS, as its particles are finer than the natural sand, which contributes high unity to the mix. The mix comprised of a high level of substitution of waste foundry sand content tends to become harsh, sticky, and stiff/inflexible beyond 30% replacement. Up to 30%, the mix was not so harsh, as we observed in mixing and placing. At a replacement rate of 30%, nearly a 15% decrease in slump value was noted. At the replacement point of 40%, the decrease in slump value was boosted up to around 31%. This reduction in workability is likely owing to the existence in WFS of water absorbing finer particles, i.e. clay-type fine material, ashes, and impurities, etc., which are accountable for reducing the fluidity of wet concrete and escalating the water demand. Similarly, a reducing trend in compacting factor (CF) values has also been noted with the increasing WFS level. The findings of this research are in agreement with those observed by ,54,55,56The compressive strength (CS) for all the mixtures consisting of WFS as a partial substitute of sand i.e., 0–40% at the increment of 10% was performed at the age of 7, 28, 56, and 91 days. The CS increased by up to 30% substitution level in linear behavior, and at the substitution level of 40%, the strength is nearly equal to the strength of the control mixture at all the ages. There is an increase in compressive strength at each replacement level, and a maximum increase in compressive strength was observed at a 30% replacement level. At 7 days of age, the percentage increase in CS as compared to the control mixture was 2.53%, 4.56%, 7.62%, and 1.45% for mixtures comprising 10%, 20%, 30%, and 40%, respectively. The concrete mixture containing 30% WFS at 7 days of age had a maximum compressive strength of 23.30 MPa, i.e., 7.62% higher than that of the control concrete. Concrete mixtures comprised of WFS of up to 10%, 20%, 30%, and 40% at 28 days of age gained 2.67%, 4.72%, 7.82%, and 1.65%, respectively, higher CS than that of the control mix.At 56 days of age, the enhancement in CS of concrete comprising of 10%, 20%, 30%, and 40% WFS respectively over that of control mixture was 7.13%, 11.31%, 12.59%, and 5.86%, respectively. Similarly, at the level of 91 days, there were 11.18%, 14.78%, 16.65%, and 9.59% increases in CS for concrete mixtures comprising of 10%, 20%, 30%, and 40% WFS respectively over that of control concrete. From This is may be due to the existence in WFS of more fine particles that acted as excellent packing material and eventually resulted in a denser concrete mix . The voiThe findings of distinct mixtures for compressive strength (CS) incorporating WFS at various ages are shown in The splitting tensile strength (STS) for all the mixtures consisting of WFS as a partial substitute were performed at the age of 7, 28, 56, and 91 days. The STS behavior of the control and WFS concrete mixtures are shown in At 56 days of age, concrete mixtures comprised of 10%, 20%, 30%, and 40% WFS achieved an increase of 5.48%, 11.17%, 13.14%, and 4.80%, respectively, over the STS of control concrete. At the age of 91 days, increments of 6.18%, 9.09%, 13.87%, and 16.07% were observed for mixtures comprising 10%, 20%, 30%, and 40% of WFS, respectively compared to the control concrete mixture. A maximum increase in STS for a concrete mixture containing 30% WFS was observed. As observed, the STS of WFS concrete mixtures increased with the age and with the WFS content up to a 30% level of substitution.The change in STS with the content of WFS was similar to that observed for CS. The results of the present study are in good agreement with the findings of ,10,11,12The splitting tensile strength (STS) tests results of different mixtures consisting of WFS at various ages are shown in Concrete tensile strength in terms of flexural strength (FS) is quite essential. The FS for concrete incorporating WFS as a partial substitute of sand was measured after the completion of 7 days, 28 days, 56 days, and 91 days of standard curing in accordance with ASTM C293 . The resThe flexural strength (FS) tests findings of different mixtures incorporating WFS at various ages are shown in This section provides information about the variation in test results at all ages. It is important to mention here that the variance in the test results of different samples is within the limits prescribed by ASTM standards. As a case study, the variance in the results of one batch i.e., M-1, is specified and given in The concrete cylindrical specimens have been heated to 300, 400, 500, 600, 700, 800, 900, and 1000 °C. The specimens were put in an open-sky environment for 30 days before assessing the compressive strength. After exposure to elevated temperatures, the concrete cylinders were then evaluated for their compressive strength. The residual compressive strength (RCS) after fire exposure was calculated as the percentage of the respective unfired/unheated specimen’s compressive strength.2O4Si starts to degrade into CaO and SiO2. This is a permanent decomposition that results in a higher loss of strength [2 follow-on in additional cracking and a drop in the concrete’s RCS [All the specimens were tested for RCS at ambient temperature in this experimental work after being exposed to a one-month cooling period in an open-sky environment. At the moment of heating/cooling, no superimposed compressive load was applied. Since the maximum strength reduction occurs in unstressed concrete rather than stressed concrete at higher temperatures , It is mstrength . The RCSte’s RCS ,64,65. MThe residual compressive strength (RCS) of various concrete mixtures incorporating WFS at various elevated temperature levels are shown in The USPV values of various concrete mixtures incorporating WFS as a partial substitute of sand after being exposed to various levels of elevated temperatures are shown in The USPV tests results are shown in The RHN tests results are shown in The RHN values after 30 days of cooling in surrounding air after exposure to 500 °C were found to be 21, 22, 23, 24, and 25 for 0%, 10%, 20%, 30%, and 40% replacement levels of WFS, respectively. The RHN values after 30 days of cooling in surrounding air after experience to 600 °C were found to be 20, 21, 22, 23, and 21 for 0%, 10%, 20%, 30% and 40% replacement levels of WFS, respectively. The RHN values after 30 days of cooling in surrounding air after experience to 700 °C were found to be 16, 17, 18, 20 and 16 for for concrete mixtures consists of 0%, 10%, 20%, 30%, and 40% WFS, respectively. The RHN values after 30 days of cooling in surrounding air after exposure to 800 °C were found to be 14, 15, 16, 18 and 14 for 0%, 10%, 20%, 30%, and 40% replacement levels of WFS, respectively. It can be seen from the very low rebound hammer number of 2 exceeds 0.94, an association in the form of {0.756 × 2.458, R2 = 0.97} seems to be fit the data connection. A higher value of coefficient of determination shows that the CS has a strong connection with the USPV test. In general, an increase in the compressive strength with the inclusion of WFS increases the value of the USPV test, which is the indication of the concrete’s quality and homogeneity.2O4Si starts to degrade into CaO and SiO2. This is a permanent decomposition that results in a higher loss of strength [2 follow-on in additional cracking and a drop in the concrete’s RCS [strength . Maximumte’s RCS ,64,65.2 exceeds 0.94, a polynomial association in different forms seems to be the best data connection with the various values of temperature and WFS contents. A coefficient of determination of R2 = 0.99 shows a strong data connection. A higher coefficient of determination value shows that compressive strength has a strong connection with various WFS content and temperature levels. Equations for each level of replacement and temperature are given below in Equations (1)–(5).As the value of RIt can be seen that the RHN decreases inconsequentially to a temperature level of 300 °C. Beyond 300 °C, it was observed that the reduction was very sharp because above 450 °C, there was a breakage of CSH and some volumetric conversions within the structure of concrete. In addition, crakes and void generation occurs due to elevated temperature damage in the concrete matrix, which leads to a decrease in RHN values.2 exceeds 0.94, a polynomial association in different forms seems to be the best data connection with the various values of temperature and WFS contents. A coefficient of determination of R2 = 0.99 shows a strong data connection. A higher value of coefficient of determination shows that the RHN value has a strong connection with various WFS content and temperature levels. Equations for each level of replacement and temperature are given below (Equations (6)–(10)).As the value of RConcrete spalling is a major parameter when concrete is to be exposed to elevated temperatures. Due to the significant loss of concrete strength at elevated temperatures, explosive spalling can cause a complete or abrupt failure. The temperature range is in between 300–650 °C. Many factors were identified as affecting explosive spalling. These factors including the age, moisture content, type of gravel and sand used, curing method, and rate of heating. Low heating rates reduced the risk of spalling.It is considered that pore pressure stresses play a major contribution in explosive spalling. Due to low tensile strength, chances of explosive spalling could be more in normal strength concrete . In thisThe fresh properties for all replacements were observed to be almost similar with the control mixture up to a 30% replacement level. The compacting factor values and slump values were decreased with the inclusion of waste foundry sand. Up to 30%, no severe effect on the slump and compacting factor tests results were observed.The strength properties i.e., compressive strengths, splitting tensile strengths, and flexural strengths values of foundry sand concrete mixtures at all ages were found to be higher than those of the control mixtures. The maximum values for strength properties were observed at a 30% replacement level. The substitutional level of normal sand with WFS was found to be optimum at 30%, and should not exceed 40%. The inclusion of waste foundry sand increases the rebound number and USPV values, which is the indication of the quality, homogeneity, and impermeableness of foundry sand concrete.The residual compressive strength of concrete decreases with increasing temperature. Air curing results in a further reduction of residual compressive strength. The residual compressive strength of the concrete containing waste foundry sand as a partial replacement of natural sand on the 30th day of air/open-sky cooling at ambient temperature after exposure to 300, 400, 500, 600, 700 and 800 °C was reduced in the range of 29.00% to 32.5%, 38.5% to 42.5%, 48.5% to 51.00%, 59.00% to 62.00%, 65.00% to 69.00%, and 68.5% to 74% of unheated compressive strength values for 0% to 40% replacement of WFS, respectively.The pattern of increase in USPV, rebound hammer, compressive strengths tests at ambient temperature before exposure to elevated temperatures, and the pattern of reduction in USPV, rebound hammer, and residual compressive strength test of foundry sand concrete was found to be similar with the increasing temperature.The maximum value for all the tests was observed before and after exposure to elevated temperatures for a 30% replacement level of waste foundry sand.In this study, concrete mixtures were prepared by the inclusion of WFS as a partial replacement of natural/regular sand, and then its effect was investigated on the fresh properties i.e., slump and compacting factor tests and strength properties i.e., compressive strength, splitting tensile strength, and flexural strength at the age of 7, 28, 56, and 91 days. The effect of inclusion of waste foundry sand as a partial replacement of sand was also investigated in terms of the effect of elevated temperatures ranging from 300 to 800 °C at the increment of 100 °C on the compressive strength of foundry sand concrete. The USPV and rebound hammer tests were performed at the age of 28 days before exposure to elevated temperatures and on the 30th day after being exposed to elevated temperatures. The spalling phenomenon in foundry sand concrete and the control samples was carefully observed in this investigation. The findings are summarized as follows.Based on the above findings, it can be concluded that waste foundry is a suitable candidate for the partial replacement of natural sand up to 30% in making concrete.


D) and in the absence of blue light at midnight (SMCN). The samples were obtained after rinsing the mouth with tap water and were analyzed for SMC by immunoassay . RQ measurements (n = 12) were realized with a portable breath to breath metabolic system , between 8:00 PM and 10:00 PM, once at either location. At SL, SMCD, and SMCN values (mean ± SD) were, respectively, 2.14 ± 1.30 and 11.6 ± 13.9 pg/ml (p < 0.05). Corresponding values at HA were 8.83 ± 12.6 and 13.7 ± 16.7 pg/ml (n.s.). RQ was 0.78 ± 0.07 and 0.89 ± 0.08, respectively, at SL and HA (p < 0.05). Differences between SMCN and SMCD (SMCN–SMCD) strongly correlate with the corresponding RQ values at SL (r = -0.74) and less tight at HA (r = -0.37). Similarly, mean daily SMC values (SMC) tightly correlate with RQ at SL (r = -0.79) and weaker at HA (r = -0.31). SMCN–SMCD, as well as, SMC values at SL, on the other hand, respectively, correlate with the corresponding values at HA (r = 0.71 and r = 0.85). Acute exposure to HA appears to loosen relations of SMC with RQ. A personal profile in daily SMC variation, on the other hand, tends to be conserved at HA.High altitude (HA) exposure may affect human health and performance by involving the body timing system. Daily variations of melatonin may disrupt by HA exposure, thereby possibly affecting its relations with a metabolic parameter like the respiratory quotient (RQ). Sea level (SL) volunteers  were examined for daily changes in salivary melatonin concentration (SMC). Sampling was successively done at SL  and, on acute HA exposure, at nearby Caspana . Saliva was collected in special vials  at sunny noon (SMC Contemporary working conditions, tend to challenge the human body internal timing system. Jet-lag , and extZeitgebers, among them the daily light/dark cycle synchronize endogenous time keepers, the biological clocks , an ubiquitous, pleiotropic, and multitasking indoleamine , all of them students enrolled in Physical Education Pedagogy at University of Antofagasta, volunteered for the present study in the context of a wider HA research project (FONDECYT 1100161). Having previously been approved by the Ethics Committee of the Faculty of Medicine, University of Chile, the latter project was also endorsed by Bioethical Committee of Faculty of Health Sciences, University of Antofagasta, considering the principles and practices stated in the Declaration of Helsinki for studies of human beings. A written informed consent was obtained from each subject finally participating in the study.Fourteen healthy volunteers (Table 2). Corresponding measurements at HA were done in the context of a pedagogic field trip, on the day after arriving by bus, at Caspana , a small village located in the Andes, 300 km east from Antofagasta.The volunteers were examined for salivary melatonin concentration (SMC) at SL, the site of their usual residence. Cardio-respiratory parameters could be obtained in only 12 of them (D) and dim, ordinary bulb light, at midnight (SMCN). After rinsing the mouth with tap water, samples of saliva (1.5 ml aprox.) were collected into special vials , The saliva samples were handled using gloves, coded and stored in liquid nitrogen, to be later on analyzed for SMC with an ELISA kit  in an independent commercial laboratory . SMCN–SMCD and SMC are, respectively, assumed to represent the amplitude of daily SMC change and the average of both day and night SMC value per subject.At SL, as well as, at the HA site, the subjects were required to provide saliva samples for SMC determination, with sun light at midday . RQ was calculated as the ratio between mean CO2 flux and mean O2 flux.Cardio-respiratory parameters were determined under resting conditions, after sitting for 5 min. The measurements were done between 8:00 and 10:00 PM, both at SL and HA, once at either location. Evening meals consisted of bread and cheese at SL, as well as at HA. Along a 3 min equilibration period, respiratory COD and SMCN at SL and HA. Pearson’s correlation coefficient and Student’s t-test were, respectively, applied for analysis of correlations and for comparison between SL and HA. Calculations were done with the aid of SPSS 22 IBM software package. Statistic significance was established at the p < 0.05 level.Mean values are expressed ± SD. ANOVA for repeated measurements was applied for comparisons between SMCTable 1). Cardio-respiratory parameters of the volunteers significantly changed on HA exposure as compared to SL (Table 2). Figure 1 shows mean values of SMC at day and night, both at SL  and HA . Mean SMC values in either those conditions were similar in women and men (data not shown). Daily variations of SMC observed at SL vanish at HA. SMCN–SMCD and SMC, respectively, depict, for the present work, the amplitude of circadian melatonin rhythm and the average value around which the oscillation occurs. These parameters strongly correlate one with the other at SL. At HA, on the contrary, this correlation weakens . RQ–SMCD relation appears to be strong at SL and weak at HA . Similarly, the RQ–SMCN relation appears to be tighter at SL than at HA . Both, SMCN–SMCD , as well as, SMC , also correlate with RQ more strongly at SL than at HAAge and body mass index were rather similar in women and men volunteering in the present study . Similarly, SMCN–SMCD at SL also tightly correlate with the corresponding values at HA . As also shown in Figure 4, the former and the latter relation, respectively, locate mainly above and below the middle line (y = x).SMCN and SMCD values differ at SL but not at HA . SMCN and SMCD, as well as, SMCN–SMCD and SMC, correlate with RQ strongly at SL and much less so at HA . Melatonin circadian rhythm, thus, may lose at HA its synchronizing grip on aspects related with energy metabolism. Individual SMC and SMCN–SMCD values at SL, on the other hand, strongly correlate with the corresponding ones at HA . Although being distorted at HA , an individual profile of circadian melatonin rhythmicity, thus, seems to persist under the latter condition . Such an individual profile of circadian melatonin rhythmicity may in the future be explored for its potential to predict the capacity for adequately dealing with challenges of the body timing system.Mean SMCSalivary melatonin has been validated as an adequate marker for phase typing of circadian regulation . AlthougN and SMCD values differ at SL but not at HA . SMCN–SMCD considered, in the present study, as the amplitude of daily melatonin variation, correlates with SMC  more strongly at SL than at HA . Distortions of SMC rhythm as shown to occur at HA  may implicate a deregulation of melatonin-dependent periodic processes. High amplitudes in circadian melatonin rhythmicity may prevent and/or delay the development of diabetes  could mean a decoupling of energy metabolism from circadian control, a possibility that certainly has further to be elucidated. It may be noticed, however, that even acute adequation of energy metabolism to HA exposure is yet far from reaching a consensus . Individual patterns in melatonin circadian rhythmicity as observed at SL, thus, appear largely to be conserved at HA. Individual circadian melatonin rhythmicity seems, indeed, to remain relatively stable (Individual values of SMCy stable . With exy stable , neithery stable . From ony stable . Some pey stable . SimilarTo summarize, a rapid ascent to an altitude of about 3,000 m a.s.l., as usual under working conditions in the Andes, tends to override the night-day difference of SMC and to weaken the relations between SMC with RQ, thus, potentially deregulating melatonin-dependent timing of body functions, affecting energy metabolism. Individual SL circadian profile of SMC tends, on the other hand, to be maintained at HA. The SL profile of melatonin circadian rhythm may be further on explored for its potential to predict individual tolerance to challenges of the body timing system at HA.CB, CW-Z, JS-U, ML, and MT were mostly implicated in the experimental design, logistics, and development of the experimental work at SL and HA. MT, CW-Z, NDG, ML, HV, MS-F, EV, OA, JS-U, H-CG, and CB substantially contributed to the conception of the work, data analysis and manuscript revision, approved the final version, and agree to be accountable for the whole work. The M.Sc. thesis of MT at the Faculty of Health Sciences, University of Antofagasta, is mainly based on this work.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.


Five different dosages of nano-SiO2 particles and five volume dosages of steel fiber were used. The durability of concretes includes permeability resistance, cracking resistance, carbonation resistance, and freezing-thawing resistance, and these were evaluated by the water permeation depth, number of cracks, total cracking area per unit area of the specimens, carbonation depth of the specimens, and the relative dynamic elastic modulus of the specimens after freezing-thawing cycles, respectively. The results indicate that the addition of nano-SiO2 particles significantly improves the durability of concrete when the content of nano-SiO2 is limited within a certain range. With the increase of nano-SiO2 content, the durability of concrete first increases and then decreases. An excessive number of nano-SiO2 particles could have an adverse effect on the durability of the concrete. The addition of the correct amount of steel fibers improves the carbonation resistance of concrete containing nano-particles, but excessive steel fiber reduces the carbonation resistance. Moreover, the addition of steel fibers reduces the permeability resistance of concrete containing nano-particles. The incorporation of steel fiber enhanced the freezing-thawing resistance and cracking resistance of concrete containing nano-particles. With increasing steel fiber content, the freezing-thawing resistance of the concrete containing nano-particles increases, and the cracking resistance of the concrete decreases gradually.An experimental study was conducted to investigate the effect ofnano-SiO Concrete has been widely used in structural engineering because of its superior characteristics, such as simple preparation techniques, low energy consumption, high durability, low price, and good bonding performance with reinforcing steel bars and plates. However, there are also a number of disadvantages when using concrete materials, including high weight, low toughness, and low tensile properties, which restrict their widespread application. One important method for modifying concrete is incorporating fiber materials into concrete composite, which can significantly enhance the mechanical performance, deformation behavior, and anti-cracking performance . Typical2 and nano-TiO2, and their results indicated that the incorporation of nano-SiO2 and nano-TiO2 significantly enhanced the durability and fatigue properties of concrete [2 and nano-Al2O3 together with polypropylene fibers can enhance freeze-thaw resistance and compressive strength of pavement concrete because of the reduced penetration and porosity of concrete [2O3 and SiO2 nano-particles on bonding properties between steel and concrete, and reported that the addition of nano-particles resulted in an enhancement in bonding strength on concrete with higher cement dosages [3 [Although the durability of concrete composite could be enhanced by the incorporation of steel fibers, it remains necessary for the concrete used in severe and highly corrosive environments to enhance its durability. In particular, after a number of cracks appear, the durability of concrete structures is significantly decreased because of disease caused by the cracks ,15,16. Wconcrete ,20,21. Sconcrete . Ismael  dosages . Wu et asages [3 .2 [3O4 [2O3 [3 [2 [2 is most commonly used in concrete. SiO2 nano-particles can accelerate generation of calcium silicate hydrate (C-S-H) gel and dissolution of tricalcium silicate (C3S) because of their hot activity, which is significantly affected by the size of SiO2, and nano-SiO2 can supply nucleating placefor the inclusion of C-S-H [2 nano-particles on mechanical, and fracture properties, and bonding performance of steel fiber reinforced concrete [2 on the durability of concrete composite reinforced by steel fibers. In this study, durability experiments  were conducted to determine the influence of nano-SiO2 and steel fibers on the durability of the concretes composite, which is the novelty of this study.The results of this study could provide design guidance for the application of concrete composite containing nano-SiO2 reinforced by steel fibers in actual engineering structures. In this study, the durability of steel fiber reinforced concrete containing nano-SiO2 is investigated.These nano-particles, together with silver nano-particles, carbon nano-tubes, and nano-fibers, are typically used for the production of commercially available building products containing nano-objects . To date2 , nano-Fe2 [3O4 , nano-Al3O4 [2O3 , nano-Ca [2O3 [3 , and nanO3 [3 [2 . Of thesof C-S-H . The durconcrete ,23. Howe2 and steel fiber on the durability of concrete.Systematic durability experiments  were conducted to determine the influence of nano-SiO2 added in the experiments was in loose amorphous powder form, and the content of SiO2 was greater than 99%. 2 and steel fiber used in concrete in other studies and our previous study [2 particles  and five volume dosages of steel fiber  were used. The total binder content was controlled as 543.4 kg/m3. 2 exhibits the greatest increase in the mechanical properties and fracture performance of concrete composites [2 was unchanged at 5%.Chinese Class 42.5R Ordinary Portland cement (Mengdian Cement Factory in Xinxiang City of China) was used, and its primary performance parameters are presented in us study ,13,33, fmposites ,13. Ther2 to be dispersed uniformly in the concrete mixture. The nano-particles and steel fibers cluster if the mixing procedure of the concrete composite is not appropriate. In this experiment, a horizontal agitator was applied to prepare fresh concrete in order to prevent clustering of the nano-particles and steel fibers. The appropriate mixing program was determined by trial and error. The fine and coarse aggregates were mixed together for 30 s, and then the nano-materials, cement, and fly ash were poured into the mixture to be stirred for a further 30 s. The steel fibers were then added and mixed for 30 s. Finally, the water containing the water reducing agent was incorporated and mixed for a final 60 s. The distribution of the fibers and nano-particles clearly affect the workability of fresh concrete and the durability of hardened concrete. During the course of the mixing, the fresh concrete mixture was randomly sampled to observe the dispersion of the nano-materials and fibers. From the workability of the fresh concretes and fracture surface of the specimens, the uniform distribution of steel fibers and nano-particles could be determined.Because of the miniscule size of nano-particles, it is difficult for nano-SiO2, and it can monitor the concentration of CO2, which should be 20%. The CO2 gas was supplied from the steel cylinder through a pipe to the carbonation box. The size of the cube carbonation specimen was 100 × 100 × 100 mm [Carbonation resistance test was carried out in the carbonation box (CCB-70A), which was manufactured by Suzhou Donghua Test Instrument Co., Ltd., Suzhou City, China. × 100 mm . The depThe dimensions of the circular truncated cone specimens for the permeability resistance test were Φ175 × 150 × Φ185 mm . The perFreeze-thaw resistance of concrete can be evaluated by the quick-freezing method after a certain number of freeze-thaw cycles of specimens. The size of the prism freeze-thaw samples was 100 × 100 × 400 mm . The spe± 2 °C) and relative humidity (60% ± 5%). The fresh concrete composites were leveled using a trowel immediately after they were poured into the mould with the surface higher than the upper surface of the mould frame. The surface of the plate specimen should be smooth. Then, the specimens were covered using a piece of plastic cloth, which was taken away after the specimens were maintained at a temperature of 20 ± 1 °C for 2 h. The electric fan standing 150 mm away from the short edge of the mould was turned on immediately after the fresh concrete composite was cast in the mould. The wind speed on the transverse center line of the specimen should be controlled as 4–5 m/s when the electric fan was blowing to the specimen surface. An iodine-tungsten lamp with the power of 1000 W was fixed 1.2 m over the transverse center line of the specimen to shine the surface of the specimen. The electric fan and iodine-tungsten lamp were continuously working for 24 h and 4 h, respectively, before they were turned off. Then the widths of the cracks on the specimen surface were measured one by one using crack width measuring device. According to the measured crack widths, the crack lengths were measured hierarchically. During the test, the initial cracking time, crack length, crack width, and number of crack were recorded. The average cracking area of a single crack, the crack numbers per unit area of the specimen, and the total cracking area in unit area of the specimen can be calculated, respectively, as follows [a is the average cracking area of a single crack, mm2; N is the total number of cracks; Wi is the maximum width of the ith crack, mm; Li is the length of the ith crack, mm; b is the number of cracks per unit area of the specimen; A is the area of the specimen surface, 0.36 m2; and C is the total cracking area per unit area of the specimen, mm2/m2.The cracking resistance test was carried out according to the standard , and the follows :(1)a=12N2 nano-particles content. As can be seen, the carbonation depth of the sample increases with increasing carbonation age. The carbonation depth first decreases, but then increases incrementally with increasing nano-particle dosage for similar carbonation ages. The minimum carbonation depth is observed when the nano-particle content reaches 7%, where the depth is 22.7% smaller than that of basic concrete without nano-SiO2.2 reacts not only with portlandite, but possibly also with other cement hydrates, primarily the calcium silicate hydrate (C-S-H) gels [2 is generated, and most of them have adverse effect to the mechanical properties and durability of concrete. There will be a second hydration reaction due to the addition of nano-SiO2. In the reaction, an amount of Ca(OH)2 inside the composite is consumed, and C-S-H gels are generated. Large amounts of C-S-H gel can increase the density of the concrete composite. There is an optimal content of nano-SiO2 for reinforcement in carbonation resistance of concrete. After the dosage of SiO2 nano-particles increases beyond the optimal content, the nano-particles are difficult to be dispersed uniformly. Therefore, the excessive nano-SiO2 content may have an adverse effect on the density of concrete, which results in an increase in carbonation depth of the sample. The influence of nano-SiO2 is similar to silica fume on carbonation resistance of concretes. Yang reported that the carbonation depth of the sample will decrease stepwise as the silica fume content increases from 0% to 5%, while the depth increases as the silica fume content increases from 5% to 10% [2 in silica fume can react with the cement hydration products, which decrease the alkalinity of the concrete. However, a significant amount of calcium silicate gel from the reaction can fill macropores inside the concrete, which could reduce the porosity of concrete and improve the strength and density [During the complex carbonation process, CO-H) gels . During % to 10% . The act density .2, is shown in The relationship between the carbonation depth of the specimens and the steel fiber dosage, containing 15%fly ash and 5% nano-SiO2 in concrete—were observed in the cement paste because of the evaporation of free water and chemical shrinkage. The incorporation of steel fiber can efficiently block the diffusion channel of CO2 and increase the resistance to CO2 diffusion. Consequently, this decreases the carbonation speed of concrete [2 to penetrate the concrete. Therefore, an excessive steel fiber fraction would decrease the carbonation resistance of concrete.After the concrete specimen was cast, a significant number of small holes—which facilitate the diffusion of COconcrete . In otheconcrete . An exce2 are shown in 2 can improve the permeability resistance of concretes. With the dosage of nano-SiO2 increasing from 0% to 5%, the permeability resistance of concretes is improved significantly with increasing nano-particle dosage. The water permeation depth of concretes incorporating 5% nano-SiO2 is decreased by 55.6% compared to concrete without nano-SiO2. However, the water permeation depth of the concrete increases gradually with increasing nano-SiO2 content when the dosage of nano-SiO2 exceeds 5%, which indicates that the permeability resistance of the concrete starts to decrease at nano-SiO2 dosages greater than 5%. This suggests that the permeability resistance of the concrete starts to decrease when the nano-SiO2 content is greater than 5%.Permeability is a fundamental material property for characterizing concrete durability because it determines the penetration of aggressive substances responsible for degradation under a pressure gradient . Concret2 with small particle size, which significantly improves the density of concrete and block the water permeability channels. The characteristic of the interfacial transition zone (ITZ) between the aggregate and cement paste has a significant impact on the permeability resistance of concrete composites. Large amounts of nano-SiO2 will significantly improve structural characteristics of the ITZ in concrete composites [2 particles, or by being cured in a colloidal solution of water-diluted nano-SiO2 oxide [2 particle can be regarded as a type of catalyzer in accelerating cement hydration because of the large free energy of nano-particles and it also acts as kernels to reduce the crystal size of Ca(OH)2 [The interspaces between cement particles can be filled by nano-SiOmposites . ArdalanO2 oxide . The nan Ca(OH)2 . As a re2 and 15% fly ash. From the variations, it can be seen that the addition of steel fiber into concrete composite incorporating nano-SiO2 and fly ash considerably increases water permeation depth.The elastic modulus of steel fibers is significantly greater than that of concrete; therefore, the addition of steel fibers would increase the tensile properties of concretes. This would effectively restrict the formation and development of initial cracks, and the porosity of the concrete could be reduced, which would be beneficial to improving the permeability resistance of concrete . In addi2 with different nano-particle dosage is shown in 2 exhibits the highest relative dynamic elastic modulus. After 25 freeze-thaw cycles, the relative dynamic elastic modulus of concrete containing 3% nano-SiO2 increased by 4.8% compared to concrete containing no nano-SiO2. When the nano-SiO2 content is greater than 3%, the relative dynamic elastic moduli increase with increasing nano-SiO2 content. The concrete containing 9% nano-SiO2 has the lowest relative dynamic elastic modulus.The relative dynamic elastic moduli of concrete incorporating nano-SiO2 is added to the concrete, the increased density is beneficial to improving the freeze-thaw resistance of concretes [2. However, the amount of internal defects in concrete could increase because of clustering of the nano-SiO2 particles if an excessive dosage is used, which would have an adverse effect on the freeze-thaw resistance of concrete.Freeze-thaw resistance is one of the most significant evaluated durability properties of concrete structures in cold environments. The freeze-thaw damage to concrete is a result of small internal cracks that are full of water that freezes in each freeze-thaw cycle, and the greater volume of ice enlarge the small cracks. The strength of concrete structures after a certain number of freeze-thaw cycles is dependent primarily on the cement paste structure, including the micropore type, pore distribution, micropore size, number of capillaries, and porosity factor . After aoncretes . As a re2 and 15% fly ash under various freeze-thaw cycles. As can be seen, the relative dynamic elastic moduli of each group are similar when the number of freeze-thaw cycles is less than 50. However, there is a clear decrease in the relative dynamic elastic modulus when the number of freeze-thaw cycles exceeds 50. With increasing steel fiber dosage, the relative dynamic elastic moduli of samples increased gradually. Compared to the concrete without steel fiber, the relative dynamic elastic modulus of concrete reinforced by 2.5% steel fibers was improved by 59.2% after the specimens were subjected to 50 cycles. When the number of cycles reached 100, the specimens without steel fibers and the specimens incorporating 0.5% steel fibers were all destroyed.Steel fibers have remarkable bonding properties with the concrete matrix. The presence of steel fibers in concrete delays and restricts the occurrence and development of cracks. The volume of the water in the cracks will expand when frozen, which increases the crack development. With increasing freeze-thaw cycles, the cement paste wrapping the coarse aggregate is desquamated, and the dense structure of concrete is destroyed. The appearance quality of the concrete reinforced with 2.5% steel fiber is significantly better than that of the concrete reinforced with 1% steel fiber.2 nano-particles on the evaluation parameters in cracking resistance of concretes. From 2 nano-particles dosage. In particular, there is a sharp decrease in the total cracking area when the SiO2 nano-particles dosage increases from 1% to 3%. With further increases from 3% to 7%, the total cracking area remains approximately unchanged. The minimum total cracking area was observed on concrete specimens incorporating 5% SiO2 nano-particles. Compared to concretes containing 5% nano-SiO2, the concrete containing 9% nano-SiO2 exhibited a smaller total cracking area, and the total cracking area increased by 71.8%. As can be seen in 2 content increasing from 0% to 7%, the number of cracks decreased from 10 to 3, whereas the number of cracks increased to 5 with further increases in nano-SiO2 content. It can be concluded that 5% to 7% nano-SiO2 could be the optimal dosage to restrict shrinkage cracking of the concrete.2 restricts shrinkage of hydration products to a certain extent and reduces the possibility of crack formation [2 particles can absorb part of the free water in the concrete and decrease the plastic shrinkage of concrete because of the large specific surface area of the nano-particles. However, excessive amounts of nano-SiO2 absorb a large amount of water, and water evaporation on surface of the concrete could also consume significant quantities of water. Therefore, the concrete shrinkage could be increased by excessive amounts of nano-SiO2.When hydration occurs, the hydration product exhibits a significantly smaller volume than the volume of each component before hydration, and chemical shrinkage in the concrete occurs. The incorporation of nano-SiOormation . The nan2. From 2 to 248.3 mm2, a decrease of 68.1%, when the dosage of steel fiber increases from 0% to 2.5%. As can be seen in 2 enhances the bonding performance between steel fibers and the concrete matrix and is beneficial for the fibers to play an anti-cracking role. Shen et al. reported that the cracking stress, ratio of cracking stress to tensile strength, and increasing steel fiber fraction resulted in greater concrete cracking resistance [The steel fibers in the concrete matrix are distributed randomly, which can support the aggregates and prevent the aggregates from sinking. The surface disintegration of the composite was reduced and the uniformity of the concrete could be improved. As a result, the fibers can effectively prevent the concrete cracking. In addition, steel fibers offer significant reinforcement on the early-stage hardened concrete, and the tensile strength of concrete can be enhanced because the concrete composite exhibits lower elastic moduli than steel fibers, which restricts the generation of cracks. The stress field inside the concrete is more continuous and uniform, and the stress concentration on the micro-crack tip can be weakened, because they can restrict further crack propagation . The ducsistance . The earsistance .2 nano-particles on the durability of concrete composite incorporating fly ash was investigated. Based on the results obtained, the following conclusions can be drawn:2 particles can significantly improve the permeability resistance, cracking resistance, freeze-thaw resistance, and carbonation resistance of concrete on condition that the SiO2 nano-particle dosage is within a certain limit. By increasing nano-SiO2 content, the permeability, cracking, freeze-thaw, and carbonation resistance of concrete were first enhanced, but then decreased. An excessive number of nano-SiO2 particles could adversely affect the durability of concrete.Application of nano-SiO2; however, an excessive fraction of steel fiber would reduce the carbonization resistance of the specimens. In addition, the addition of steel fiber reduced the permeability resistance of the composite reinforced by nano-SiO2. Reinforcement of steel fibers enhanced the freezing-thawing and cracking resistance of concrete incorporating nano-SiO2. By increasing steel fiber volume content, the freeze-thaw resistance of concrete incorporating nano-particles exhibited an increasing trend, and the cracking resistance of the concrete decreased gradually.Incorporation of the correct amount of steel fibers improved the carbonation resistance of the concrete containing nano-SiOIn this study, the influence of steel fibers and SiO


We found a significant correlation between c-MET expression, EGFR expression (p = 0.010) and EGFR mutations (p = 0.013), as well as a trend (p = 0.057) with regards to TP53 mutant activity. In conclusion this study demonstrated a strong correlation between EGFR mutations, TP53 and c-Met expression in therapy-naïve primary resection samples. Moreover, we found two new c-Met mutations that warrant further studies.The c-Met receptor is a therapeutically actionable target in non-small-cell lung cancer (NSCLC), with one approved drug and several agents in development. Most suitable biomarkers for patient selection include c-Met amplification and exon-14 skipping. Our retrospective study focused on the frequency of different c-Met aberrations  in 153 primary, therapy-naïve resection samples and their paired metastases, from Biobank@UZA. Furthermore, we determined the correlation of c-Met expression with clinicopathological factors, Epidermal Growth Factor Receptor (EGFR)-status and TP53 mutations. Our results showed that c-Met expression levels in primary tumors were comparable to their respective metastases. Five different mutations were detected by deep sequencing: three  previously described and two never reported . I333T, a new mutation in the Sema(phorin) domain of c-Met, might influence the binding of antibodies targeting the HGF-binding domain, potentially causing innate resistance. E168D and S203T mutations showed a trend towards a correlation with high c-Met expression ( The therapeutic landscape of non-small-cell lung cancer (NSCLC) harboring oncogenic driver alterations has revolutionized by the introduction of tyrosine kinase targeted inhibitors (TKIs), such as Epidermal Growth Factor Receptor (EGFR) , and AnaThe L858R mutation and exon 19 deletion in EGFR as well as Anaplastic Lymphoma Kinase (ALK) translocation have been demonstrated as reliable biomarkers for the response to EGFR , respectFor c-Met, it has been established that its aberrations  represent oncogenic drivers  and resiSeveral clinical trials with c-Met TKIs  and not by fluorescence in situ hybridization (FISH) or mutation analysis. Therefore, we aimed to determine the correlation between c-Met expression and other c-Met aberrations  or EGFR mutation status.With regards to EGFR-targeted agents, exon 19 deletions and exon 21 L858R substitutions, termed classic mutations, represent the most common genetic alterations, accounting for approximately 90% mutations in NSCLC adenocarcinomas and resulting in a high sensitivity to the first generation of EGFR-TKIs ,33.The main resistance mechanism to the first- and second-generation TKIs is the occurrence of the T790M mutation detected in more than 50% of the patients after disease progression . OsimertTP53 is a tumor suppressor that is mutated in 50% of lung cancers . Three tIn the present study, we aimed to investigate the c-Met-biomarker status of targeted therapy-naïve NSCLC patients, thus assessing the patient population potentially eligible for c-Met-TKIs as a first-line treatment. Subsequently, given the intertwining of the c-Met, EGFR and TP53 pathways, we addressed our efforts to determine both the gene-  and protein-expression status (c-Met and EGFR) of these targets in a TKIs-naïve NSCLC patient population, and correlate these different results with each other.Of note, these studies detected five different mutations of c-Met: three  previously described, and two never reported . In particular, I333T, a new mutation in the Sema (phorin) domain of c-Met, might influence the binding of antibodies targeting the HGF-binding domain, such as onartuzumab, potentially causing innate resistance. These results support that a deep tumor profiling will be an important part of clinical management of NSCLC patients, when using new c-Met inhibitors, and warrant further investigation.The expression level and amplification status of c-Met were determined in 153 primary formalin fixed paraffin embedded (FFPE) NSCLC tumors from EGFR-TKI naïve patients. In total, 151/153 of the IHCs were eligible for scoring. Forty-eight percent (72/151) of samples showed high c-Met expression (2+/3+).p = 0.016), with a high c-Met expression in 56% of adenocarcinomas versus 35% of squamous and 9% of large cell carcinomas or not otherwise specified (NOS). The expression was independent of smoking history (p = 0.725), gender (p = 0.497), tumor differentiation (p = 0.160), invasiveness (p = 0.377), tumor status/T (p = 0.544), lymph node status/N (p = 0.061) and metastatic status/M (p = 0.380). The Kaplan-Meier curve shows no influence on the survival time (p = 0.785) (This expression was correlated with the tumor histology (= 0.785) .A total of 108 out of 153 samples for chromogenic in situ hybridization (CISH) were interpretable, out of which only four (3.7%) displayed c-Met amplification: ratios c-Met/CEN7 4.54, 2.61, 2.05 and 2.00. Only the sample with a ratio of 4.54 showed focal amplification of c-Met. Half of the c-Met amplified samples, including the sample with a ratio of 4.54, showed a high c-Met expression (3+), the others had a score of 0. The internal controls were positive in all samples.p = 0.006) in c-Met expression in primary tumor samples vs metastases.Forty-one paired metastases (27 synchronous and 14 metachronous) were tested. The Cohen’s kappa test (high: (3+ and 2+) vs low (1+ and 0)), with a kappa-value of 0.430, showed a moderate agreement  between the c-Met expression and the timing of the metastasis (synchronous/metachronous). One patient showed c-Met amplification in the primary tumor (ratio 2.05), but not in the synchronous lymph node metastasis. From the other c-Met-amplified tumors, no metastatic tissue was available. Another patient showed amplification (ratio 2.31) in a metachronous liver metastasis but not in the primary tumor itself.There was no significant correlation  were positive (2+/3+) for EGFR-IHC, while 14/45 (31%) had EGFR mutations: L858R (eight cases), exon 19 deletion (three cases) and exon 20 insertion (three cases). This high percentage might be explained by the high percentage of non-smokers in this cohort of patients.p = 0.010) between EGFR and c-Met expression was found. Here, 20% of samples with EGFR-IHC 0 show high c-Met expression, versus 35% of EGFR 1+, 84% of EGFR 2+ and 92% of EGFR 3+ samples.A significant correlation (p = 0.436) between the types of EGFR mutation and c-Met expression. The two EGFR-tested c-Met-amplified samples were EGFR-WT. The sample with a ratio of 2 showed an EGFR expression of 1+, whereas the sample with a ratio of 4.54 showed an expression of 2+.In EGFR-mutated samples, a high c-Met expression (2+ and 3+) was found in all 14/14 samples , versus Exon 14 skipping of c-Met was found in two patients, with an allelic ratio of 12% and 39%. Both samples showed a high c-Met expression. The first sample also had a co-occurring c-Met S203T mutation.In 14/69 sequenced primary tumor samples, five non-synonymous mutations in c-Met  were fouN375S is a germline mutation  within tThe germline E168D mutation leads to a higher affinity for HGF and higher susceptibility of c-Met for SU11274 . The E16https://zhanglab.ccmb.med.umich.edu/I-TASSER/), in which the position of this residue and the structure of the interface region are predicted to be not substantially unaffected by the isoleucine to threonine mutation . When comparing the different mutations separately, there was a strong trend (p = 0.058) towards an association between two c-Met mutations and c-Met expression. Here, two patients with an E168D mutation both showed 3+ c-Met expression. The S203T mutation was found in seven patients, one showed no c-Met expression, one showed 1+ and five showed 2+ expression. All other patients with c-Met mutations showed no to low expression. c-Met mutations did not correlate with EGFR status.There was no association between the c-Met expression and the mutation status (p = 0.381). The TP53 mutations were divided into partial-active and non-functional groups according to the TP53 Mut Assessor tool of the TP53 database [Inactive TP53 mutations were found in 43% of patients (30/69) . The TP5database , based op = 0.057) was found, with 72% of p53 non-functional samples presenting with a high c-Met expression as compared to 36% of p53 partially-functional samples. Invasiveness [p = 0.131). Here, 75% of tumors with non-functional TP53 showed an invasive phenotype, versus 40% of tumors with partially active TP53.When comparing c-Met expression with TP53, a strong trend  rabbit monoclonal antibody (9.75 µg/mL antibody)  or the ready-to-use anti-total EGFR (3C6) mouse monoclonal antibody , as exemplified by the representative images in The DNA was isolated with a Reliaprep FFPE gDNA tissue kit . High-resolution melting (HRM) was performed . 2 µL ofTM) assay  with MID for Illumina Miseq .with a MiSeq Reagent Kit v2 (500 cycles).A library containing all exons of c-Met and TP53, including known mutation hot-spots, was prepared with the custom designed TPME Multiplex amplification of Specific Targets for Resequencing (MASTRhttp://www.biomina.be/app/variantdb/) was used to identify Single Nucleotide Variants (SNV). The NM_000245.2 sequence was used for c-Met, while NM_000546.5 was used for TP53 sequences. Mapping on crystal structures was performed with Yasara view (yasara.org). Statistical analysis was performed with SPSS  using the Chi2-test, Kaplan-Meier test, log-rank Mantel-Cox and Cohen’s kappa test.An in-house annotation and filtering tool VariantDB  (availabIn conclusion, this study revealed a strong correlation between EGFR expression and EGFR mutations, as well as TP53 mutations and c-Met expression, in therapy-naïve primary resection samples. Secondly, we found a moderate agreement in the c-Met status between the primary resection tissues and the paired metastases. Finally, we identified a new mutation in the ligand-binding domain of c-Met, I333T, which might influence the binding of antibodies targeting the HGF-binding domain. This evidence supports the notion that c-Met represents a primary potential target in NSCLC, also demonstrating a high clinical relevance in the treatment with EGFR-TKIs, since previous research showed that mutations in the c-Met receptor might cause innate resistance to antibodies .


Matrix-assisted laser desorption ionization time-of-flight (MALDI-TOF) mass spectrum of POSS-S-PA acquired in a dithranol matrix, which has specifically designed for intractable polymeric materials. The observed characterization results signposted that novel organo-inorganic hybrid POSS-S-PA would be an efficacious material for fuel cells as a proton exchange membrane and high-temperature applications due to its thermal stability of 380 °C.Herein, we demonstrate a facile methodology to synthesis a novel methacrylic phosphonic acid (PA)-functionalized polyhedral oligomeric silsesquioxanes (POSSs) via thiol-ene click reaction using octamercapto thiol-POSS and ethylene glycol methacrylate phosphate (EGMP) monomer. The presence of phosphonic acid moieties and POSS-cage structure in POSS-S-PA was confirmed by Fourier transform infrared (FT-IR) and nuclear magnetic resonance ( In recent years, polyhedral oligomeric silsesquioxanes (POSSs), a family of nanostructured inorganic components with size tunability and functionality, have fascinated global research communities due to their wide range of potential applications in viscosity modifiers, catalysis, coating, drug-delivery vehicles, electronics, and renewable energy sources ,2,3. AddIn this communication, we report on the development of a novel type of methacrylic phosphonic acid-functionalized POSSs for fuel cells. To the best of our knowledge, there is no report available based on the synthesis and characterization of methracrylate phosphate-functionalized POSSs (POSS-S-PA). Via thiol-ene click reaction chemistry, octamercapto thiol POSSs were functionalized with 7∼8 phosphonic acid (PA) groups, paving the way for use as a potential candidate for proton exchange membrane fuel cells due to its anhydrous proton conduction group, high thermal, hydrolytic, and oxidative stabilities ,22.2,2′-Azobis(isobutyronitrile) (AIBN) was purchased from Fischer, Seoul, Korea and used after purification. 3-Mercaptopropyl trimethoxysilane , anhydrous dichloromethane (DCM), triethyl amine (TEA), and methanol  were donated by Sigma Aldrich, Yongin, Korea. Ethylene glycol methacrylate phosphate  was purchased from Shanghai Angewchem Co., Ltd. .The synthesis of POSS-S-PA involves two steps. The first step includes the synthesis of POSS-SH from 3-mercaptopropyl trimethoxysilane by acid hydrolysis reaction , which i2 atmosphere for about 2 h at 40 °C. Then, freshly distilled EGMP  was injected into the reaction mixture to carry out the polymerization reaction for 5 h at 40 °C. In order to retain the POSS-cage structure, EGMP was added slowly, dropwise, for up to 30 minutes. The obtained product was kept in a refrigerator overnight, and white precipitate was then separated from DCM using rotatory evaporation. The obtained white precipitate, designated as POSS-S-PA, was further purified by dissolving in methanol and re-precipitation in diethyl ether to remove unreacted POSS-SH, and then filtered and dried. The yield of light yellow POSS-S-PA was 64% and a schematic for the synthetic route is shown in The second step for the synthesis of POSS-S-PA from POSS-SH is explained as follows: The methacrylic PA-terminated hybrid-network polymer POSS-S-PA was synthesized by the so-called “thiol-ene” reaction ,23,24 usA novel methacrylic POSS-S-PA has been synthesized using octamercapto thiol-POSS and ethylene glycol methacrylate phosphate (EGMP) monomer via thiol-ene click reaction. Further, as-prepared POSS-S-PA was characterized by NMR, FTIR, MALDI-TOF, TG-DTG, and SEM analyses to confirm their hybrid structure.1H-NMR and 13C-NMR spectra of precursor MPTS and product POSS-SH are given in 1H-NMR spectra of POSS-SH and POSS-S-PA. From the 1H NMR spectrum of POSS-SH, three signals are observed at 0.72, 1.68, and 2.52 ppm due to methylene protons on the mercaptopropyl arm and another triplet signal is exhibited at 1.34 ppm, which is attributed to thiol proton. The peak analysis provides an integral of 2:2:2:1 for an eight-armed thiolated POSS peak of 1, 2, 3, and 4, respectively. In POSS-S-PA, the successful completion of reaction between POSS-SH and EGMP has been confirmed by the absence of thiol triplet peak at 1.34 ppm as well as the absence of resonance from the ethylene proton in the range 4.5–6.5 ppm as shown in H2), 1.62 , 2.31 , 0.93  2.09  1.83  4.14 , 4.25 , 2.60 .The m/z. In addition, some other unassigned signals are observed along with main peaks, but the ultimate product for a building block of the octamer SQ cage is confirmed by elemental and NMR analyses. The unassigned peaks observed may be due to the hexamer and heptamer of the SQ cage, which could not be isolated selectively during the synthesis. The elemental analysis data of both POSS-SH and POSS-S-PA are as follows: POSS-SH: Calculated—C 47.9, H 9.39 and S 42.67; found—C 47.82, H 10.20 and S 42.60%; POSS-S-PA: Calculated—C 45.35, H 6.82, O 33.80 and S 14.03; found—C 45.12, H 6.82, O 33.98 and S 14.08%. These observations are strongly consistent with earlier results [Besides, the MALDI-TOF MS spectrum shows two strong signals at 1018 and 2474 m/z for POSS-SH and POSS-S-PA, respectively, as displayed in  results ,26.31P-NMR analysis, and it is displayed in 29Si NMR spectrum of 3 region, which confirms the presence of the POSS cage structure. The main signals are observed from −66.10 to −66.38 ppm and from −66.40 to −66.70 ppm and assigned to the cage-like octamer (T8) and the cage-like decamer (T10), respectively. Moreover, the absence of a silanol group signal in the 29Si NMR spectrum of POSS-S-PA confirms the stable SQ cage structure without any degradation during the course of reaction.The presence of PA terminal groups in the synthesized sample is further confirmed by −1 attributed to characteristic Si–O–Si stretching and S–H stretching vibrations of POSS-SH, respectively [thiol-ene click reaction formed POSS-S-PA is confirmed by the presence of C=O, C–H stretching and P–OH peaks are at 1732, 2850–3050, and 3600 cm−1, respectively, as well as the absence of an S–H peak in the region of 2620 cm−1. The observed FTIR peaks and its corresponding assignments of POSS-SH and POSS-S-PA are tabulated in FTIR spectroscopy analysis is performed to confirm the various structural organization in POSS-S-PA functional groups as well as to distinguish thiol and double bonds conversion individually ,28. Figuectively ,30. The TG-DTA curves of POSS-SH and POSS-S-PA hybrids are provided in In summary, a novel strategy of a PA-functionalized SQ cage was successfully prepared with high yields by a rapid one-pot synthesis via thiol-ene click reaction. The excellent purity of the as-prepared POSS-S-PA framework was confirmed by NMR, FTIR, and MALDI spectral analyses. Our hybrid structure of POSS-S-PA possessed good thermal stability, which was exposed by TG-DTA. From the observed results, POSS-S-PA would be an excellent inorganic–organic hybrid material for high-temperature applications and as a proton exchange membrane in fuel cells to help to increase the protonic transport, which in turn improves its protonic conductivity and cell performance.