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The investigation of variations in the microcrack frequency and microcrack length in andesites with different weathering grades: an example of İzmir, Bayraklı andesite quarries
No full textzmir, Bayraklı ilçesi, Çiçek mahallesinde bulunan terkedilmiş andezit taş ocakları günümüzde yerleşim alanı içerisinde kalmaktadır. Farklı ayrışma derecelerindeki andezitlerde artan boşluk suyu basıncı ve ayrışma derecesine bağlı olarak duraylılık sorunları meydana gelmektedir. Bu çalışmada, ayrışma derecesiyle, ince kesitler üzerinde ölçülen mikrokırıkların uzunluklarının ve en önemlisi farklı yönlerdeki mikrokırık sayısının ilişkisinin incelenmesi amaçlanmıştır. Bugüne kadar yapılan çalışmalarda, mikrokırık ölçümleri gerek ince kesit gerekse taramalı elektron mikroskobu görüntüleri üzerinde yapılarak ayrışma derecesi tayini yapılmıştır. Ancak, birçok çalışmada, mikrokırık uzunluğunun belirlenmesinde kullanılan yöntem öklid uzunluğu (iki nokta arasındaki doğrusal uzaklık) eşitliğine dayanmaktadır. Aslında mikrokırıklar nadiren doğrusaldır ve çoğunlukla yüzeyde pürüzlü çizgiler olarak görülür. Bu nedenle, az, orta ve ileri derecede ayrışmış andezit örnekleri üzerinde mikrokırıklar bilgisayar programında sayısallaştırılarak, kartezyen obje uzunluğu hesaplamasıyla gerçeğe yakın, yüksek hassasiyette mikrokırık uzunlukları ölçülmüştür. Mikrokırık uzunluklarının, ayrışma derecesiyle pozitif ve güçlü bir korelasyona sahip olduğu belirlenmiştir. Mikrokırık yönelimlerinin ince kesit üzerinde yatay ve düşey traverslerde ölçülen mikrokırık sayılarını etkilediği ve iki yöndeki farkın ayrışma derecesinin artmasıyla birlikte arttığı görülmüştür.The abandoned andesite quarries in İzmir, Bayraklı, Çiçek district remains in the settlement area at present time. Stability problems occur in andesites with various weathering grades due to the increasing pore pressure and weathering grade. In this study, it was aimed to investigate the relationships between the microcrack length, especially the number of microcrack measurements on thin sections, and the weathering grade. To date, studies on weathering grade determination with microcrack measurements either on the thin section or scanning electron microscope images have been performed. However, in most of the previous studies, the method that based on Euclidian distance (linear distance between two points) equation was utilized to measure the microcrack length. Indeed, the microcracks are barely linear and they present mostly rough lines on the surface. For the reason, the microcracks in slightly, moderately, and highly weathered andesite samples were measured with high precision and a realistic approach by digitizing them via computer software in cartesian object length computation. It was determined that the length of the microcracks has a positive and significant correlation with the weathering grade. It was revealed that the orientations of microcracks effect the number of microcracks that measured along horizontal and vertical traverses and the difference between two traverses increases with the increasing weathering grade
Electrospun modified PAN-porphyrin nanofiber electrode for caffeine detection
No full textIn this work, caffeine sensitive electrospun polyacrylonitrile-(5,10,15,20-tetra(4-tert butylphenyl)-porphyrin)/carbon felt electrode (PAN-Por/CFE) nanofiber (NF) electrochemical sensor was fabricated. In this manner, this work presents a new approach for simple, improvable and cost-effective electrochemical caffeine sensor by including coating of CFE with PAN-Por NF via electrospinning method. To the best of our knowledge, this is the first study that covers the fabrication of caffeine sensitive electrospun electrochemical sensors that included (5,10,15,20-tetra(4-tert butylphenyl)-Por). In order to obtain this modified electrode, PAN-Por precursors were prepared and then deposited on CFE via electrospinning. Physicochemical characterizations of NFs obtained by adding pure PAN and different ratios of Por were conducted by using scanning electron microscopy, fourier transform infrared, ultra violet visible and polarization optical microscope techniques. Electrochemical characterization of PAN-Por/CFE was performed by cyclic voltammetry, linear sweep voltammetry and differential pulse voltammetry. For the developed caffeine sensor, limit of detection was calculated as 14.06 μM in the linear range of 15–1000 μM. Meanwhile, the limit of quantification was defined as 42.60 μM while for 50 μM caffeine, the relative standard deviation value was calculated as 0.58%. Accordingly, the proposed method was successfully applied for the determination of caffeine in different coffee samples with recoveries ranging from 99.3% to 102.4%
Outcomes of high-risk breast lesions diagnosed using image-guided core needle biopsy: results from a multicenter retrospective study
No full textPURPOSE The clinical management of high-risk lesions using image-guided biopsy is challenging. This study aimed to evaluate the rates at which such lesions were upgraded to malignancy and identify possible predictive factors for upgrading high-risk lesions. METHODS This retrospective multicenter analysis included 1.343 patients diagnosed with high-risk lesions using an image-guided core needle or vacuum-assisted biopsy (VAB). Only patients managed using an excisional biopsy or with at least one year of documented radiological follow-up were included. For each, the Breast Imaging Reporting and Data System (BI-RADS) category, number of samples, needle thickness, and lesion size were correlated with malignancy upgrade rates in different histologic subtypes. Pearson's chi-squared test, the Fisher-Freeman-Halton test, and Fisher's exact test were used for the sta-tistical analyses. RESULTS The overall upgrade rate was 20.6%, with the highest rates in the subtypes of intraductal papilloma (IP) with atypia (44.7%; 55/123), followed by atypical ductal hyperplasia (ADH) (38.4%; 144/375), lobular neoplasia (LN) (12.7%; 7/55), papilloma without atypia (9.4%; 58/611), flat epithelial atypia (FEA) (8.7%; 10/114), and radial scars (RSs) (4.6%; 3/65). There was a significant relationship between the upgrade rate and BI-RADS category, number of samples, and lesion size Lesion size was the most predictive factor for an upgrade in all subtypes.CONCLUSION ADH and atypical IP showed considerable upgrade rates to malignancy, requiring surgical excision. The LN, IP without atypia, pure FEA, and RS subtypes showed lower malignancy rates when the BI-RADS category was lower and in smaller lesions that had been adequately sampled using VAB. After being discussed in a multidisciplinary meeting, these cases could be managed with follow-up instead of excisio
Preventing False Memories and Revitalizing Collective Memory with the Help of Historical Cartographic Materials and GIS: An Examination of the Lost Piers of Mersin
No full textPiers are vital elements in the formation of collective memory in Mediterranean port cities and they played an important role in Mersin's urban life until the 1950s. Although there are some oral history-based studies attempting to spatialize them, they lack any measure of accuracy and reliability, and carry the risk of leading to false memories. In this context, the aim of this paper is to illustrate that collective memory can be properly reconstructed by using historical maps only if appropriate methods of analysis and reliable maps are used. In this study, which is based on various historical maps of Mersin city, the locations of the lost piers have been determined by using georeferencing tools available in QGIS. The study reveals that the tendency to construct false memories could be prevented by using reliable maps and appropriate tools in GIS in combination with the archive records
Rectus abdominis and rectus femoris muscle thickness in determining nutritional risk in critically ill patients: a prospective cohort study in Turkey
No full textObjectives: Malnutrition is a clinical condition that is frequently seen in critically ill patients in the intensive care unit (ICU). Although there are many scoring systems and tools used to determine nutritional risk, those that can be used in critically ill patients in the ICU are very few. The scoring systems used are insufficient to identify ICU patients with malnutrition or at risk.Malnutrition is generally presented with a decrease in skeletal muscle mass and muscle strength. Therefore, in many recent studies, attention has been drawn to the relationship between nutritional status and loss of muscle mass.
Design: A cohort study.
Setting: Forty-five patients hospitalised in an anaesthesia ICU in Turkey were included in the study.
Participants: Patients aged 18 years and older.
Interventions: Demographic data of patients included in the study, and Nutritional Risk Screening 2002 (NRS-2002) and Modified Nutrition Risk in Critically ill (mNUTRIC) scores in the first 24 hours of ICU admission were noted. Rectus abdominis muscle (RAM) and rectus femoris muscle (RFM) thicknesses were measured by the same person (intensive care specialist) with ultrasonography (USG).
Outcome measures: Finding a quantitative and practical evaluation method by determining the correlation of measurement of RAM and RFM thickness with USG with NRS-2002 and mNUTRIC score, which are scoring systems used to assess nutritional risk.
Results: The performance of RAM and RFM thickness in determining nutritional status was evaluated by receiver operating characteristic (ROC) analysis. Area under the ROC curves were calculated as >0.7 for RFM and RAM measurements (p<0.05). Specificity and sensitivity percentages of RAM were found to be higher than RFM in determining nutritional status.
Conclusion: This study showed that RAM and RFM thickness measured by USG can be a reliable and easily applicable quantitative method that can be used to determine nutritional risk in the ICU
Using Alprazolam before phacoemulsification cataract surgery reduces complications and duration of the surgery
No full textPurpose: To evaluate the effect of preoperative Alprazolam on complications of phacoemulsification cataract surgery, duration of surgery and early reoperation rate. Methods: Records of 1026 eyes of 1026 consecutive patients underwent phacoemulsification with topical and intracameral anesthesia between 2016 and 2020 years were retrospectively reviewed. Patients were divided into two groups, with or without using Alprazolam before surgery. Patients with planned first-time surgery for senile cataract and at least three months follow-up postoperatively were included. Those who had pseudoexfoliation, small pupil, zonular weakness, corneal and hearing problem as well as traumatic, brown, mature, hypermature, and posterior polar cataracts were excluded. Main outcome measures were duration of surgery, posterior capsule rupture, rapid posterior capsule opacification (PCO) formation requiring the neodymium: yttrium–aluminum-garnet (Nd:YAG) laser and reoperation rate in early postoperative periods. Results: Alprazolam and control groups included 490 and 536 eyes, respectively. Mean surgical time was shorter in Alprazolam group (10.2 ± 3 versus 12.2 ± 4 min; < 0.001). Rate of posterior capsule rupture was higher in control group (4 versus 15 eyes; = 0.02). Four eyes (0.8%) in control group underwent unplanned secondary surgical procedures in early postoperative period (P = 0.126). Rate of rapid PCO formation was higher in control group (1 versus 9 eyes; = 0.027). Conclusions: Using Alprazolam before phacoemulsification can lead to less posterior capsule rupture, short operation time and prevent repetitive surgery. It also reduces rapid PCO formation and, thus, early Nd:YAG laser intervention due to better cleaning the posterior capsule during surgery. We conclude that Alprazolam not only reduces intraoperative complications, but also facilitates their management
Enhancing the performance of an unglazed solar air collector using mesh tubes and Fe3O4 nano-enhanced absorber coating
No full textIn the current article, it is intended to improve the performance of an unglazed solar air collector using mesh tubes as extended heat transfer surfaces and nano-enhanced black paint as a thermal conductivity booster of the absorber coating material. In this regard, three types of unglazed solar air collectors have been designed, produced and simultaneously tested containing a conventional (unmodified) system, a system with only mesh tube modification and a system with combined usage of mesh tubes and nano-enhanced absorber coating. It should be stated that Fe3O4 nanoparticles have been utilized within the scope of this work. Integrating nanoparticles to the absorber coating material (industrial matt black paint) averagely improved the thermal conductivity as 0.031 W/mK. The experimental process was tested at fixed air flow rate (0.0115 kg/s) in winter climatic conditions. As result of the experimental analysis, average thermal efficiency values were attained between 45.11 and 63.36%. Combined usage of mesh tubes and nano-enhanced black paint upgraded the mean thermal performance as 40.45% in comparison to the unmodified system. Also, obtained exergetic efficiencies are in the range of 5.49–9.96%. In addition to the energy-exergy analysis, enviro-economic survey was performed within the scope of the current work. Payback periods of the analyzed systems were found between 0.31 and 0.34 years
Letter to the Editor: “Translation and validation of Cerebral Palsy Quality of Life Questionnaire‐Teen in Hong Kong Chinese population [CP QoL‐Teen (HK)]”
No full textLetter to edito
The Historical, Topographic and Architectural Definitions of "GELaNDEMAUER" City Walls in Karia
No full textIn the early 4th Century BC, the systematical constructions of 'Gelandemauer' city walls began in Karia under the Hekatomnid rule. Henceforth, 'Gelandemauer' city walls became the most advanced and sophisticated fortification system in Western Anatolia, both in tactical and topographical points, until the end of the 3rd century BC. On this type of city wall, defined by scholars as "Gelandemauer" circuits, the traces of walls follow the high ridges and summits of the lands, aiming to gain the topography's natural defense advantage. Therefore, the city walls built according to the "Gelandemauer" planning model surround larger areas than those required for civic buildings. These fortifications' topographical layout, tactical design, and construction method demonstrate the concept of advanced territorial defense. At the same time, the tradition of rural "Lelegian" residential architecture and stonework, entirely existing in the Halikarnassos Peninsula before the Hekatomnid rule in Karia, gave shape to the rustic appeal and economic character of the Hekatomnid 'emplekton' technique which would be adopted to requirements of the art of the 'poliorketic' siege warfare in Hellenistic period. In many cases, the initial construction of "Gelandemauer" city walls was also carried out using various masonry techniques based on distinct variants of 'emplekton' (ashlar, trapezoidal, polygonal, pseudo-polygonal) while considering the different topographical conditions, except for later repair. On the other hand, the architectural characteristics of 'Gelandemauer' in the region emerged as the consequence of the fact that Hekatomnids had supported the urbanization process and had undertaken the reconstructions of the prominent sanctuaries of the Karian League while installing an extent fortification network for defending the territory of the Karian Satrapy. In this regard, the Hekatomnid building program in military architecture has distinct characteristics that had a long-term influence on the design of Hellenistic fortifications. Maussollos' settlement policy based on urbanization by 'synoecism' that radically transformed the rural residential organization in Karia essentially determined the development of 'Gelandemauer' in the region. Since the end of the 4th century BC, adopting a similar settlement policy to the synoecism of Maussollos, many of the Macedonian leaders (Eupolemos, Pleistarkhos, Demetrios Poliorketes, Lysimakhos) principally fortified their 'metropoleis' with 'Gelandemauer' city walls. Accordingly, as appeared in the City of Herakleia ad Latmum (Pleistarkheia), reestablished by Pleistarkhos at the end of the 4th or the beginning of the 3rd century BC, this fortification technique was promoted by being modified to the advanced siege warfare engineering (poliorketic). It could be reasonably said that both cities carry the architectural memory of 'Gelandemauer' in Karia. Considering the transference of the architectural technique of Hekatomnid 'emplekton' in the city walls of Halikarnassos to the Early Hellenistic fortification of Herakleia ad Latmum, in this respect, Halikarnassos and Herakleia ad Latmum are significant cities of which the city walls could be taken as descriptive patterns to define the architectural and topographic details of 'Gelandemauer'; at the same time, it is also essential to emphasize the fact that these ancient Karian cities experienced similar settlement processes depending on 'synoecism' and in this manner, they were fortified with similar 'Gelandemauer' city walls.
Fortification building projects planned for the defense of Halikarnassos in the second quarter of the 4th Century BC and Herakleia ad Latmum at the end of the 4th - early 3rd century BC contributed to the continuity of 'Gelandemauer' in Karia. Therefore, it should be considered that Karia is among the places where the architectural improvements in the design of 'Gelandemauer' city walls could uninterruptedly be pursued during the period from Maussollos' rule to the end of the 3rd - the beginning of the 2nd century BC when Philippos V. and Antiokhos III attempted to invade this region. Ancient cities fortified with "Gelandemauer" are mostly the centers of the political confederations called "koina" (e.g., Messene), or administrative centers of a kingdom or a regional political power (e.g., Syracuse in Sicily, Samos in Ionia, Halikarnassos, Herakleia ad Latmum in Karia, Demetrias in Thessalia, Antiokheia in Kilikia). Studying the evolution of "Gelandemauer" city walls in Karia to classify the ancient defense systems according to their architectural techniques, topographical designs, and chronological phases will undoubtedly contribute to the knowledge about urbanization and resettlement patterns in the region during the Classical and Hellenistic periods