Earthquake environmental effects and ESI 2007 of the 6th February 2023 Kahramanmaraş earthquakes along the East Anatolian Fault Zone (Türkiye)

The February 6, 2023 Kahramanmaraş earthquake doublet resulted in a range of devasting impacts on the built and natural environments. Here the macroseimic intensity of the event is assessed using the Environmental Seismic Intensity Scale (ESI 2007), which considers a range of primary and secondary earthquake environmental effects (EEEs) resulting from the causative earthquakes. These features were documented as part of the hybrid Earthquake Engineering Field Investigation Team (EEFIT) mission and by numerous other studies in the aftermath of the earthquakes. The primary fault ruptures along segments of the East Anatolian Fault Zone exceeded 350 km along the Pazarcık segment (the first fault to rupture) with a maximum displacement (Dmax) of ∼8 m, and 150 km with a Dmax ∼7–8 m along the Çardak-Sürgü Fault, which subsequently ruptured later the same day in an event termed the Elbistan or Ekinözü earthquake. In addition, a range of other secondary effects such as landslides and rockfalls, liquefaction and lateral spreading, changes to springs, tsunami and widespread damage were reported over an area \u3e35,000 km2. These data indicate epicentral intensities of XI and X for the Pazarcık and Elbistan earthquakes, respectively, consistent with the intensity inferred from measured offsets along these faults. Whereas site intensities based upon various secondary effects range from VIII – XI. Given the close association in time and space of the two main shock events it is difficult to attribute the wider off-fault secondary features to either event, especially where the faults converge in the north, but there is good correlation with: a) the mapped fault traces and many documented EEEs occur with 10–15 km of the rupture; and b) measured peak ground acceleration (PGA), where ESI 2007 intensities of \u3e X correspond to regions experiencing \u3e0.2 g PGA, and there are a few EEEs where PGA did not exceed 0.05 g. However, both maximum reported moment magnitude intensity (MMI) and Did You Feel It (DYFI) reports are 1–3° lower than the ESI 2007 values derived here, possibly resulting from bias towards urban areas. These data not only highlight the utility of using environmental effects in earthquake intensity studies but also suggest that the Kahramanmaraş earthquakes are unprecedented within the historical record of the region

Earthquake environmental effects and ESI 2007 of the 6th February 2023 Kahramanmaras¸ earthquakes along the East Anatolian Fault Zone (Türkiye)

The February 6, 2023 Kahramanmaraş earthquake doublet resulted in a range of devasting impacts on the built and natural environments. Here the macroseimic intensity of the event is assessed using the Environmental Seismic Intensity Scale (ESI 2007), which considers a range of primary and secondary earthquake environmental effects (EEEs) resulting from the causative earthquakes. These features were documented as part of the hybrid Earthquake Engineering Field Investigation Team (EEFIT) mission and by numerous other studies in the aftermath of the earthquakes. The primary fault ruptures along segments of the East Anatolian Fault Zone exceeded 350 km along the Pazarcık segment (the first fault to rupture) with a maximum displacement (Dmax) of ∼8 m, and 150 km with a Dmax ∼7–8 m along the Çardak-Sürgü Fault, which subsequently ruptured later the same day in an event termed the Elbistan or Ekinözü earthquake. In addition, a range of other secondary effects such as landslides and rockfalls, liquefaction and lateral spreading, changes to springs, tsunami and widespread damage were reported over an area >35,000 km2. These data indicate epicentral intensities of XI and X for the Pazarcık and Elbistan earthquakes, respectively, consistent with the intensity inferred from measured offsets along these faults. Whereas site intensities based upon various secondary effects range from VIII – XI. Given the close association in time and space of the two main shock events it is difficult to attribute the wider off-fault secondary features to either event, especially where the faults converge in the north, but there is good correlation with: a) the mapped fault traces and many documented EEEs occur with 10–15 km of the rupture; and b) measured peak ground acceleration (PGA), where ESI 2007 intensities of > X correspond to regions experiencing >0.2 g PGA, and there are a few EEEs where PGA did not exceed 0.05 g. However, both maximum reported moment magnitude intensity (MMI) and Did You Feel It (DYFI) reports are 1–3° lower than the ESI 2007 values derived here, possibly resulting from bias towards urban areas. These data not only highlight the utility of using environmental effects in earthquake intensity studies but also suggest that the Kahramanmaraş earthquakes are unprecedented within the historical record of the region

Hybrid EEFIT mission to february 2023 Kahramanmaraş earthquake sequence

The southwestern part of Türkiye was hit on 6 February 2023 by an Mw 7.8 (epicentre:Pazarcık) and then an Mw 7.5 earthquake (epicentre: Elbistan). The event was followed by tensof thousands of aftershocks including the Mw 6.3 event on 20 February (epicentre: Uzunbağ).This paper reports on the preliminary findings of the mission organised by the UK’s EarthquakeEngineering Field Investigation Team (EEFIT) to the Kahramanmaraş Earthquake sequence ofFebruary 2023. This mission followed a hybrid model, combining field and remote investigationtechniques, to investigate the characteristics of the earthquake sequence, its impact on buildingsand infrastructure, as well as the efficacy of relief, response and recovery operations. The keymessages include that the building stock is hard to categorise which brings along difficulties withdamage assessment, that the recovery and reconstruction require multi-sectoral engagement ofkey stakeholders, and that the auditing and quality control mechanisms within the constructionindustry need revisiting in the way forward for better disaster resilience in Türkiye

The Türki̇ye earthquake sequence of February 2023: A longitudinal study report by EEFIT

On 6 February 2023 at 4:17 am local time, a large area in southeastern Türkiye and northern Syria was hit by an Mw 7.8 earthquake, which was followed by an Mw 7.5 earthquake at 1:24 pm local time, causing the loss of more than 50,000 lives, some 100,000 injuries and significant damage to buildings and infrastructure, estimated to be in the range of 84.1 billion USD for Türkiye alone. The largest earthquake in Türkiye since the deadly 1939 Erzincan earthquake with however much larger losses, the sequence immediately attracted the attention of the global post-disaster reconnaissance/engineering communities. This included the Earthquake Engineering Field Investigation Team (EEFIT), who, within one week of the event, gathered a team with 30 people from academia and industry in the UK (19), Türkiye (5), New Zealand (1), Hungary (1), Bulgaria (1), Greece (1) and USA (1) with two support members from the UK and the Netherlands, to study the events and their impacts, and also to develop suggestions to reduce the existing vulnerabilities in the future. The team was organised in the form of 6 working groups as shown below, which were (1) strong ground motions and seismotectonics, (2) geotechnics, (3) structures, (4) infrastructure, (5) remote sensing and (6) relief response and recovery

Effect of bleaching on sound enamel and with early artificial caries lesions using confocal laser microscopy

The aim of this study was to evaluate effect of bleaching agents on sound enamel (SE) and enamel with early artificial caries lesions (CL) using confocal laser scanning microscopy (CLSM). Eighty blocks (4 × 5 × 5 mm) of bovine enamel were used and half of them were submitted to a pH cycling model to induce CL. Eight experimental groups were obtained from the treatments and mineralization level of the enamel (SE or CL) (n=10). SE groups: G1 - unbleached (control); G2 - 4% hydrogen peroxide (4 HP); G3 - 4 HP containing 0.05% Ca (Ca); G4 - 7.5% hydrogen peroxide (7.5 HP) containing amorphous calcium phosphate (ACP). CL groups: G5 - unbleached; G6 - 4 HP; G7 - 4 HP containing Ca; G8 - 7.5 HP ACP. G2, G3, G6, G7 were treated with the bleaching agents for 8 h/day during 14 days, while G4 and G8 were exposed to the bleaching agents for 30 min twice a day during 14 days. The enamel blocks were stained with 0.1 mM rhodamine B solution and the demineralization was quantified using fluorescence intensity detected by CLSM. Data were analyzed using ANOVA and Fisher's tests (α=0.05). For the SE groups, the bleaching treatments increased significantly the demineralization area when compared with the unbleached group. In the CL groups, no statistically significant difference was observed (p>0.05). The addition of ACP or Ca in the composition of the whitening products did not overcome the effects caused by bleaching treatments on SE and neither was able to promote remineralization of CL.Department of Restorative Dentistry UNOPAR - University of North Paraná, Londrina, PRDepartment of Restorative Dentistry Dental School University of Illinois at Chicago, Chicago, ILDepartment of Dental Materials and Prosthodontics Araçatuba Dental School Universidade Estadual Paulista (UNESP), Araçatuba, SPDepartment of Restorative Dentistry Piracicaba Dental School UNICAMP - University of Campinas, Piracicaba, SPDepartment of Dental Materials and Prosthodontics Araçatuba Dental School Universidade Estadual Paulista (UNESP), Araçatuba, S

In vitro evaluation of the microhardness of bovine enamel exposed to acid solutions after bleaching

Acid erosion is a superficial loss of enamel caused by chemical processes that do not involve bacteria. Intrinsic and extrinsic factors, such as the presence of acid substances in the oral cavity, may cause a pH reduction, thus potentially increasing acid erosion. The aim of this study was to evaluate the microhardness of bleached and unbleached bovine enamel after immersion in a soda beverage, artificial powder juice and hydrochloric acid. The results obtained for the variables of exposure time, acid solution and substrate condition (bleached or unbleached enamel) were statistically analyzed by the ANOVA and Tukey tests. It was concluded that a decrease in microhardness renders dental structures more susceptible to erosion and mineral loss, and that teeth left unbleached show higher values of microhardness compared to bleached teeth

2023 Türki̇ye deprem sekansi deprem mühendi̇sli̇ği̇ saha çalişmalari eki̇bi̇ (EEFIT) Misyonu: Türkçe geni̇şleti̇lmi̇ş özet

Türkiye'nin güneydoğusunda ve kuzey Suriye'de geniş bir alan, 6 Şubat 2023 tarihinde yerel saatle sabaha karşı 04:17'de gerçekleşen 7.8 büyüklüğünde yıkıcı bir depremle sarsıldı, aynı gün içerisinde 13:24’te meydana gelen 7.5 büyüklüğündeki deprem ile yıkımın boyutu ve etki alanı büyük ölçüde arttı. Bu depremler, yalnızca Türkiye'de 84.1 milyar $’ı (≈2.5 trilyon ₺) aşan ekonomik kayba, bina ve altyapı stokunda ciddi hasara, 100,000'den fazla yaralı ve 50,000'den fazla can kaybına neden oldu

Method to obtain platelet-rich plasma from rabbits (Oryctolagus cuniculus )

Abstract: Platelet-rich plasma (PRP) is a product easy and inxpesnsive, and stands out to for its growth factors in tissue repair. To obtain PRP, centrifugation of whole blood is made with specific time and gravitational forces. Thus, the present work aimed to study a method of double centrifugation to obtain PRP in order to evaluate the effective increase of platelet concentration in the final product, the preparation of PRP gel, and to optimize preparation time of the final sample. Fifteen female White New Zealand rabbits underwent blood sampling for the preparation of PRP. Samples were separated in two sterile tubes containing sodium citrate. Tubes were submitted to the double centrifugation protocol, with lid closed and 1600 revolutions per minute (rpm) for 10 minutes, resulting in the separation of red blood cells, plasma with platelets and leucocytes. After were opened and plasma was pipetted and transferred into another sterile tube. Plasma was centrifuged again at 2000rpm for 10 minutes; as a result it was split into two parts: on the top, consisting of platelet-poor plasma (PPP) and at the bottom of the platelet button. Part of the PPP was discarded so that only 1ml remained in the tube along with the platelet button. This material was gently agitated to promote platelets resuspension and activated when added 0.3ml of calcium gluconate, resulting in PRP gel. Double centrifugation protocol was able to make platelet concentration 3 times higher in relation to the initial blood sample. The volume of calcium gluconate used for platelet activation was 0.3ml, and was sufficient to coagulate the sample. Coagulation time ranged from 8 to 20 minutes, with an average of 17.6 minutes. Therefore, time of blood centrifugation until to obtain PRP gel took only 40 minutes. It was concluded that PRP was successfully obtained by double centrifugation protocol, which is able to increase the platelet concentration in the sample compared with whole blood, allowing its use in surgical procedures. Furthermore, the preparation time is appropriate to obtain PRP in just 40 minutes, and calcium gluconate is able to promote the activation of platelets

Microcomputerised tomography evaluation of 10% carbamide peroxide applied to enamel

Objectives. There is still some controversy in the dental literature whether carbamide peroxide bleaching causes demineralization of teeth. One of the reasons for this controversy is that there is as yet no reliable, non-destructive in vitro metod for assessing mineral loss in bleached teeth. The objective of this study was to investigate the possible demineralization effect of 10% carbamide peroxide bleaching agent on enamel and dentine non-destructively