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The influence of moisture on the physical (density) and mechanical (modulus of rupture-MOR, modulus of elasticity-MOE) properties of Populus x canadensis M. were figured out by three three-point bending tests and ultrasonic testing . Samples were conditioned at 20±1 °C and 45, 65, and 85% relative humidity. The calculated ultrasonic longitudinal wave velocity (VLL) was used to determine dynamic MOE (4549 to 4735 MPa) and compared to static MOE (5461 to 5910 MPa). Static MOE values are around 15.3% to 28.1% higher than dynamic values. MOR values, the most influenced properties, decreased from 70.1 MPa to 51.3 MPa with the increase in moisture. Pearson correlation coefficients ranged from 0.52 (MOR vs VLL) to 0.94 MOEdyn vs VLL). The R² values ranged from 0.187 (VLL vs MOR at 85% RH) to 0.94% (VLL vs Edyn at 65% RH).

Twelve elastic constants (Young’s modulus (EL, ER, and ET,), shear modulus (GLR, GLT, and GRT) and Poisson’s ratios (νLR, νLT, νRT, νTR, νRL, and νTL)) of Populus canadensis M. were determined by ultrasonic testing and evaluation, and the effect of thermal treatment on these constants was figured out. Samples were modified at 110, 160, and 210 °C for 3 and 6 h. The 2.25 MHz pressure and 1 MHz shear waves were propagated to calculate ultrasonic wave velocities, which were used to dynamically predict the constants. The control values for EL, ER, ET, GLR, GLT, GRT, νLR, νLT, νRT, νTR, νRL, and νTL were 4361 MPa, 1438 MPa, 476 MPa, 771 MPa, 480 MPa, 107 MPa, 0.795, 0.296, 0.863, 0.335, 0.19, and 0.027, respectively. Yet, no data for full elastic constants were reported, and some remarkable differences were observed for moduli and Poisson ratios when compared to other poplar species. Elasticity and shear moduli reached their highest at 160 °C 3h and 110 °C 3h conditions, respectively. The common point of the treatment on moduli was that intense application caused the highest adverse effect, particularly for ET and GRT. Contrary to moduli, apart from νRT and νTR, the lowest values for Poisson’s ratios were not obtained at the intense application. In general, none of the properties presented linear-like advancement or worsening by the increase in treatment conditions. Furthermore, not all the properties were significantly influenced by the treatment. Therefore, defining an optimum thermal treatment condition for improving the wood elastic constants is not easy when considering that the response to thermal treatment changes not only between the species but also within the species. Anyhow, preventing extended duration to elevated temperatures provides considerable advances.

The objective of this work was to evaluate the effect of growth ring number (specimens including 2, 4, and 6 rings from the bark) and growth ring width on elastic constants in the radial direction of Populus x canadensis, which has not been revealed before. The longitudinal (2.25 MHz) and transverse (1 MHz) ultrasonic waves were propagated to calculate the longitudinal (VRR) and shear (VRL, VLR, VTR, and VRT) wave velocities and used to determine the elasticity modulus (ER), and shear moduli (GRL and GRT). The average growth ring widths of specimens including 2, 4, and 6 rings were 17.0 mm, 17.8 mm, and 18.2 mm, respectively. According to the results, only VRL steadily increased with increased ring number, while other velocities fluctuated. The same fluctuations were observed for moduli except for GLR, which constantly increased with ring number. The influence of ring number on velocity was statistically significant only for VRL and VRT. However, all moduli were significantly affected by ring number. Linear regression statistics revealed that there were significant relations between the ring width and density, VRL, VLR, VRT, GRL, and GRT.

Aim: Acute kidney injury (AKI) is a clinical syndrome that can cause disturbances in fluid-electrolyte and acid-base balance, resulting in the accumulation of nitrogen and uremic toxins along with the loss of kidney functions within hours or days. In this study, it was aimed to retrospectively examine patients with acute kidney injury to determine whether there is a relationship between infection parameters and urine volume. Materials and Methods: The study included a total of 144 patients with (n=74) and without infection (n=70) out of 294 patients with AKI who received treatment between 1 January 2020 and 31 December 2021 in the nephrology clinic of a tertiary university hospital. Results: The mean age was 66.4±15.7 (range:19-95) in patients with infection and 63.8±15.2 (range:36- 93) in non-infected patients. 51.4% (n=38) of those with infection and 52.9% (n=37) of those without infection were women. There was no difference between the individuals with and without infection in terms of age and gender (p>0.05). Infection was present in 51.4% (n=74) of the patients included in the study. Urinary tract (31.3%) and respiratory tract infections (13.2%) were the most common in those with infection. A moderate negative correlation was observed between admission CRP and discharge creatinine level in patients with infection. There was no correlation between PCT and sedimentation rate, urine volume and admission/discharge creatinine level. Moderate positive correlations were found between admission/discharge PCT and admission/discharge urine volume in patients without infection. In addition, moderate negative correlations were found between admission/discharge sedimentation rate and admission urine volume. Conclusions: No correlation was found between PCT and sediment (incoming/exit) and outflow urine volume in patients with infection.

Abstract There are many parameters that could be used to evaluate the quality of scientific meetings such as publication rates of meeting abstracts as full-text articles after the meeting or scoring with validated quality scales/tools that evaluate individual papers, project proposals, or submitted abstracts. This study aimed to determine the full-text publication rates for abstracts presented at Turkish National Medical Education Congresses and Symposia and to assess the quality of given abstracts. Abstracts presented at national medical education congresses and symposia between 2010 and 2014 in Türkiye were evaluated. Initially, the abstracts were evaluated if they were published as full-text articles in international and national peer-reviewed journals following the meeting. Secondly, the quality of presented abstracts was assessed with the Medical Education Research Study Quality Instrument (MERSQI) scale. Overall publication rate for the abstracts was 11.3%. The publication rate of oral and poster presentations were 26.6% and 8.1%, respectively. Oral presentations had a statistically higher publication rate than poster presentations (p = .000). The mean MERSQI score for abstracts was 7.73 ± 2.59. The oral presentations had higher MERSQI mean scores than poster presentations (8.28 ± 2.46 vs. 7.61 ± 2.6; p = .032). Similarly, published abstracts had a significantly higher score compared to unpublished abstracts (10.07 ± 2.74 vs. 7.43 ± 2.41; p = .000). Interestingly, there was no statistical difference between the mean MERSQI scores of the published oral and poster presentations (9.33 ± 2.45 vs. 10.61 ± 2.72; p = .101). This study showed that the main factor for a meeting abstract to be published as a full-text article is the scientific quality of the study. The quality of presentations at annual medical education meetings in Türkiye were low compared with international meetings which did not improve over five years. An institutional policy that would set quality standards for medical education research and increase the awareness of researchers on the topic might help improve the design, execution, and reporting of such studies in Türkiye. The MERSQI could be a valuable tool to monitor the quality of submitted abstracts and to increase the awareness of novice researchers on high quality research.

In this study, physical and chemical properties of heat treated cedar (Cedrus libani A. Rich.) wood were investigated. Heat treatment was carried out at four different temperatures (120, 150, 180 and 210 °C) and three different time period (2, 5 and 8 hours). The chemical properties of the obtained samples were determined using FT-Infrared spectroscopy. Heat treatment generally causes changes in the cell wall, hemicellulose degradation and reduction, long chain molecule modification, and accessible OH groups in wood. The hydroxyl group changes (H1429/897) were determined, and the crystal structure after 8 hours of heat treatment was 1.21, 1.33, 1.25, and 1.14, respectively. Changes in the cellulose chains were detected at the peak (A1370/670) and showed differences with the control sample at four different temperatures (120,150, 180, and 210°C) and in an 8-hour time period (3.13, 3.60, 3.33, 1.29) values were obtained. Carbonyl peaks at 1740nm increased with time and heating periods. The most apparent changes takes place at 180 and 210 °C for 8 hours treatment.

Wood is a complex, natural structure and an essential source of nutrition, construction and building materials, energy, etc. Because of its microscopic structure, it is difficult to model its composition. In this study, the bio-mimicry of annual rings of the wood was evaluated by modeling and printing four different models with different ring diameters. The CATIA v5 software was used for 3D modeling. The designed models were additively manufactured using a 3D printer via the fused deposition of the acrylonitrile butadiene styrene (ABS) filament. The infill density and type, shell, layer height, and printing speed were evaluated for their influence on the structure of the ring. According to the results of preliminary biomimetic experimental, none of the models were exactly printed using the FDM method and ABS filament. Furthermore, the printing parameters did not significantly improve ring structure formation. Only the earlywood section of Model 4 could be moderately printed. Therefore, using these tools with printing parameters and materials was not found to be suitable for bio-mimicry of tree rings even if the size of the rings was multiplied by ten. In future work, the same models will be printed using different methods and tools to evaluate the printing ability or differences.

Background and Aim: Severe acute respiratory syndrome coronavirus 2 is a novel coronavirus that is responsible for the current pandemic. In earlier studies, loss of respiratory function had been observed in survivors. The degree of respiratory function loss and if any early intervention may reduce or prevent it remains an issue to be clarified. The study aimed to investigate the effects of pulmonary rehabilitation through a supporting device on COVID-19 patients during a follow-up period of 1 month. Materials and Methods: In this study, patients were selected among those who had applied to emergency service, were evaluated by a pulmonary medicine resident or specialist, and were required hospital admission. The admission began on March 29th, and the study concluded on June 1st. Respiratory exerciser and peak flow meters were provided to the patients for respiratory function testing. Results: Eighty-four patients admitted to the ward were evaluated for the study between these dates. Thirty-five patients were found suitable for the study. The median discharge Peak Expiratory Flow (PEF) value was 225 ml/min (180–285), and the median follow-up PEF value was 465 ml/min (312–515) with an absolute difference of 175 ml/min (85–250). No difference between absolute PEF values and percentages was seen between the control and study groups (P = 0.374 and P = 1.0, respectively). A negative correlation between the Charlson Comorbidity Index and follow-up PEF value was observed (P = 0.009). Conclusions: There was no difference in the utilization of respiratory exercise in the initial period of COVID-19 in our study. These results could be interpreted that COVID-19 patients with no respiratory disease history and low morbidity may not require respiratory exercise to return to basal respiratory function (ClinicalTrials ID: NCT04826731).

Heat treatment is one of the environmentally friendly and cost-effective modification methods applied for improvements of wood properties. However, influences of exposure duration and temperature should be known to provide balanced improvements for properties. In this study, effect of temperature (80, 120, 150, 180, and 210°C) and exposure duration (2, 5, and 8 h) on the longitudinal ultrasonic wave velocity, density, dynamic Modulus of Elasticity-MOE (Edyn), MOE in bending, and Modulus of Rupture (MOR) properties of Taurus cedar (Cedrus libani) was figured out. Edyn was predicted using ultrasonic wave velocity of 2.25 MHz longitudinal ultrasonic wave propagated through the longitudinal axis. The three-point bending test was performed to determine static mechanical properties. According to results, the highest adverse effects of extended duration and temperature were observed for MOR and followed by Edyn, and MOE in bending. Up to 150°C and 8 h treatment levels, some remarkable increases (15.3%) were observed particularly for MOE in bending. Coefficients of determinations were calculated as 0.83, 0.38, and 0.37 for Edyn vs MOE in bending, Edyn vs MOR, and MOE in bending vs MOR, respectively.

Abstract Data on health problems and fatal complications associated with coronavirus disease (COVID-19) have consistently been reported. Although immune thrombocytopenia has been associated with multiple viral infections, only few studies have shown its association with COVID-19. Here, we have reported a case series of two cases pertaining to patients diagnosed with COVID-19-associated immune thrombocytopenia, elaborating on the clinical course, management, and response to treatment.

Abstract INTRODUCTION: Sepsis is an important cause of mortality and morbidity, and inflammatory response and oxidative stress play major roles underlying its pathophysiology. Here, we evaluated the effect of intraperitoneal etanercept administration on oxidative stress and inflammation indicators in the kidney and blood of experimental sepsis-induced rats. METHODS: Twenty-eight adult Sprague Dawley rats were classified into Control (Group 1), Sepsis (Group 2), Sepsis+Cefazolin (Group 3), and Sepsis+Cefazolin+Etanercept (Group 4) groups. Kidney tissue and serum samples were obtained for biochemical and histopathological investigations and examined for the C reactive protein (CRP), tumor necrosis factor-alpha (TNF-α), triggering receptor expressed on myeloid cells (TREM), and malondialdehyde (MDA) levels. RESULTS: The levels of TNF-α, TREM, and MDA in serum and kidney samples were significantly higher in rats from sepsis group than in rats from control group (p < 0.05). Group 3 showed a significant reduction in serum levels of TNF-α, CRP, and TREM as compared with Group 2 (p < 0.05). Serum TNF-α, CRP, TREM, and MDA levels and kidney TNF-α and TREM levels were significantly lower in Group 4 than in Group 2 (p < 0.05). Serum TNF-α and TREM levels in Group 4 were significantly lower than those in Group 3, and histopathological scores were significantly lower in Group 3 and Group 4 than in Group 2 (p < 0.05). Histopathological scores of Group 4 were significantly lower than those of Group 3 (p < 0.05). CONCLUSIONS: Etanercept, a TNF-α inhibitor, may ameliorate sepsis-induced oxidative stress, inflammation, and histopathological damage.

Mechanic properties of wood material change depending on lots of natural and environmental factors. Temperature is one of these factors and in this study, effect of temperature on Young’s modulus of Oriental beech wood was investigated. Longitudinal direction (L) compression test samples exposed to 120, 150, 180 and 210°C temperature for 2, 5 and 8 hours. A drying oven that operates in an atmospheric environment was used for temperature treatment. Static and dynamic Young’s modulus values were determined or predicted by compression test and ultrasonic wave propagation method, respectively. Results compared with each other by regression analysis to determine how successful the ultrasonic measurement is. All test samples, 20x20x60 mm, acclimatized at 20 ±2°C and 65% RH conditions. Deformation values of the tested samples were obtained by using bi-axial extensometer and then stress-strain curves were created. Static Young’s modulus was calculated by using stress-strain values from the linear elastic region of these curves. Edyn was predicted by using ultrasonic wave velocity and sample density values. Velocities were calculated by using time of flight values obtained by ultrasonic measurements. Reasonable and good relations between dynamic and static modulus of elasticity were determined by the coefficient of determination results that ranged from 0.78 to 0.94 in terms of temperature and exposure duration. Consequently, L direction Young’s modulus of Oriental beech wood that exposed to temperature can be well predicted by using ultrasonic measurement.

Neoklasik Teori, 1929 Büyük Buhranı ve ardından Genel Teori’nin yayımlanması ile birlikte Kuhn’cu anlamda bir kriz yaşamış, ancak belirli bir süre sonra bu kriz aşılmış, başka bir deyişle paradigma değişimi gerçekleşmemiştir. Başka bir ifadeyle, Neoklasik Teori, geliştirildiği dönemden itibaren kısa süreli kriz dönemi hariç günümüze kadar “normal bilim” olma özelliğini korumuştur. Literatürde oldukça geniş yer bulan eleştirilere rağmen Neoklasik teori ve bu teorinin çağdaş versiyonları iktisat eğitiminde, özellikle lisans düzeyinde, neredeyse geçerli tek yaklaşım olarak okutulmaktadır. Neoklasik iktisat eleştirisi olarak ortaya çıkan Post Otistik İktisat Hareketi’nin önemli özelliği, iktisat eğitiminin öznesi, teknik anlamda “çıktısı” olarak adlandırılabilecek olan öğrenciler tarafından geliştirilmesiydi. 2000 yılında Fransa’da bir grup iktisat öğrencisi tarafından başlatılan Post Otistik İktisat, anaakım ya da Neoklasik iktisadı eleştiren farklı grupların oluşturduğu bir harekettir. Öğrenciler, yayımladıkları bildirilerde kurgusal dünyalardan kurtulmak istediklerini, matematiğin kontrolsüz kullanımına karşı olduklarını ve iktisattaki yaklaşımlarda çoğulculuk taraftarı olduklarını ifade etmişlerdir. Post Otistik İktisat Hareketine göre mevcut iktisat eğitimi, daha doğrusu iktisat eğitiminin büyük bölümünü kapsayan Neoklasik teori ve Neoklasik teoriden türetilen yaklaşımlar, genel olarak bu beklentileri karşılamaktan uzaktır. Öğrenciler bildirilerinde üniversite eğitiminin iki temel özelliği, derslerin çeşitliliği ve öğrencinin eleştirel düşünce ile eğitilmesi gerekliliğini vurgulamaktadır. Ancak Neoklasik yaklaşımda bunların ikisi de mümkün değildir ve ikincisi çoğu zaman aktif biçimde caydırılmaktadır. Hareketin temsilcileri, Neoklasik teorinin yanısıra Marksist, Keynesyen, Kurumsalcı ya da Evrimci iktisat gibi alternatif teorilerin de öğretilmesi gerektiğini savunmaktadır. Post Otistik İktisat yaklaşımına göre, teknik olarak donanımlı, ancak sosyoloji, tarih ve kendi disiplinlerinin gelişimi anlamında yetersiz iktisatçıların yetiştirilmesinin temel nedeni matematiğin aşırı bir şekilde kullanılmasıdır. Bu çalışmanın amacı, Post Otistik İktisat hareketinin görüşlerini açıklamak ve bu anlamda iktisat eğitiminin belirtilen özelliklerini tartışmaktır. Çalışma Giriş ve Sonuç bölümleri dışında üç bölümden oluşmaktadır. Birinci bölümde Post Otistik Hareketi’nin ortaya çıkışı ve temel özellikleri açıklanmaktadır. İkinci bölümün konusu Hareket’in eleştirilerinde temel öneme sahip Neoklasik iktisadın eleştirisi yer almaktadır. Üçüncü ve son bölümde iktisat eğitimine ilişkin tartışmalara yer verilmiştir.

In this study, fatigue strength of red pine (Pinus brutia Ten.) wood was evaluated by applying 15 and 20 cycles per minute and 30% to 70% – 5 different load of static bending strength to small clear wood specimens. The study showed that fatigue life of Turkish red pine wood amounted over 1 million cycles when the stress level was 30 and 40%. In general, there is an inverse relationship between load level (S) and fatigue life (N). This relationship was modeled using nonlinear regression. Fatigue life of red pine wood can be predicted using the equation of Log (N) = A * log (S) + B. Since, fatigue tests are time consuming, only 15 and 20 cycles per minute frequencies were used in the study. By applying more and less frequent loading schemes, the fatigue behavior of red pine wood can be well understood.

Background and objective: Fluid overload is a common and serious problem that leads to severe complications in dialysis patients. We aimed to compare hydration status as measured with bioimpedance analysis (BIA) method in hemodialysis (HD) and peritoneal dialysis (PD) patients, as well as investigating the association between blood pressure, left ventricular mass index (LVMI) and hydration status. Materials and methods: We examined 43 HD and 33 PD patients. Blood pressure was recorded. In each group, echocardiographic examinations were performed on all patients. Hydration status was assessed using multifrequency bioelectrical impedance analysis. Overhydration was defined as an overhydration (OH)/extracellular water (ECW) ratio of >0.15. Results: The OH/ECW ratio was significantly higher in PD patients compared to post-HD patients. Overhydration was statistically more frequent in PD than in post-HD patients (30.3% vs. 11.6%, P = 0.043). Systolic blood pressure (SBP) in both post-HD and PD groups, and LVMI in the PD group were found to be significantly higher in overhydrated patients than non-overhydrated patients. In multiple linear regression analyses, increased OH/ECW ratio was independently associated with higher SBP and LVMI. Conclusions: Fluid overload may be an even more prevalent and serious problem in PD patients. Overhydration is closely associated with increased blood pressure and LVMI. OH/ECW ratio, a derived parameter of fluid load measured by BIA, was a significant and independent determinant of SBP and LVMI.

Aims. Sleep disorders have recently become a significant public health problem worldwide and have deleterious health consequences. Obstructive sleep apnea (OSA) is the most common type of sleep-related breathing disorders. We aimed to evaluate anthropometric measurements, glucose metabolism, and cortisol levels in patients with obstructive sleep apnea (OSA). Materials and Methods. A total of 50 patients with a body mass index ≥30 and major OSA symptoms were included in this study. Anthropometric measurements of the patients were recorded and blood samples were drawn for laboratory analysis. A 24-hour urine sample was also collected from each subject for measurement of 24-hour cortisol excretion. Patients were divided equally into 2 groups according to polysomnography results: control group with an apnea-hypopnea index (AHI)