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Risk factors for omental metastasis and the effect of omentectomy on survival in type 2 endometrial cancer patients
No full textTo investigate the risk factors for occult omental metastasis and the effect of omentectomy on the survival of type 2 endometrial cancer (EC) patients. This study enrolled patients who were diagnosed with high-risk (grade 3, serous, clear cell, undifferentiated, carcinosarcoma, or mixed type) EC between 2000 and 2021 and underwent surgery in our center. Data from 482 patients were analyzed retrospectively. Omentectomy was performed in 405 (84.0%) patients. Omental metastases were detected in 61 (12.7%) patients. Eighteen (29.5%) of these metastases were occult. Adnexal involvement, malignant cytology, and peritoneal spread were independent risk factors for omental metastasis. The 5-year overall survival (OS) rate was 59.5% in patients who underwent omentectomy and 64.7% in those who did not (P = 0.558). In patients with and without omental metastases, the overall 5-year OS rates were 34.9% and 63.5%, respectively (P < 0.001). The 5-year OS rates of patients with a normal omentum, gross tumors, and occult metastases were 63.5%, 26.9%, and 52.5%, respectively (P < 0.001). Omental metastases is not uncommon in type II endometrial cancer; approximately one third of patients have occult metastases. Factors - positive cytology, adnexal involvement, and peritoneal involvement are associated with higher probability of omental metastase
Response spectrum shapes implied by earthquakes in Turkey: comparisons with design spectra
No full textDesign spectrum shape in many recent standards and codes is defined by spectral accelerations for two periods, Ts,(~0.2s) and T1,(~1 s), modified by multiplicative factors that account for the site class and strength of the ground shaking. This article draws attention to apparent discord between spectra from actual recordings at a number of stations of the national strong motion network of Turkey with the design spectra for the same location and site characteristics as given by the national seismic hazard map. We find that, for deep basins with Site Class D or E profiles, the design spectrum seems not to recognize consistently the constant velocity and longer period demand. If this conjecture is true, it may foreshadow unsafe designs for the building stock in Turkey in similar environments. Many more earthquake recordings than are currently at hand are needed to verify the applicability of using the two-point design spectrum that is embedded in the regulation. This is not a unique problem only to the Turkey Building Earthquake Regulation (TBER 2018). The recently recorded strong ground motion records from the 06 February 2023, M 7.7 and M 7.5 Kahramanmaraş, earthquakes support the conjecture of this study and provide strong evidence for a need to revise the corner periods of the design spectrum in the Regulation
Macro- and microplastic abundance from recreational beaches along the South Aegean Sea (Türkiye)
No full textThis study aimed to evaluate the abundance and diversity of macro- and microplastics in sand samples collected during summer and winter from eight different beaches used for recreational purposes located on the South Aegean coasts of Türkiye. According to the results, microplastic in fiber shape was dominant on all the beaches. The highest microplastic abundance was determined at Ölüdeniz Kumburnu Beach (360.00 ± 237.66 particles kg−1 dw) in summer and at Aktur Beach (358.33 ± 397.24 particles kg−1 dw) in winter. A significant positive correlation was found in the winter between microplastic amounts and wind speed. The study area is an important touristic center faraway from major cities and industrial areas. Thus, plastic pollution in this area may be the result of tourism activities in the summer, discharge waters from wastewater treatment plants or transportation by meteorological factors (like waves, wind or river flows)
The reliability and validity of the 3-m backward walk test in people with Parkinson's disease
No full textBackgroundPeople with Parkinson's disease (PwPD) lose the ability in backward walking which is an important part of mobility in daily life. The 3-m backward walk test (3MBWT) evaluates backward walking; however, its reliability and validity have not been examined in PwPD yet.AimsTo examine (1) the test-retest reliability of the 3MBWT in PwPD; (2) the minimum detectable change in the 3MBWT times; (3) the concurrent and known-groups validity of the 3MBWT; and (4) the optimum cutoff time which best discriminates fallers from non-fallers with Parkinson's disease (PD).MethodsThis cross-sectional study included 36 PwPD and 33 healthy people. The 3MBWT was conducted with the 10-m walk test, timed up and go test, Berg Balance Scale, four square step test, activity-specific balance confidence scale, Movement Disorders Society Sponsored Unified Parkinson's Disease Rating Scale, and Hoehn and Yahr Scale.ResultsThe 3MBWT demonstrated excellent test-retest reliability (ICC = 0.965). The MDC of 2.13 s was determined. The 3MBWT had moderate to high correlations with the other outcome measures (correlation coefficient ranged from -0.592 to 0.858). On the 3MBWT times, there were significant differences between PwPD and healthy people, and between fallers and non-fallers with PD (p < 0.001 and p < 0.001, respectively). A 3MBWT time of 10.31 s was found to best discriminate fallers from non-fallers with PD.ConclusionsThe 3MBWT is a reliable, valid, and easy to administer outcome measure to assess backward walking performance in PwPD, indicating it to be used in practice and research
Degradation of Phenol in the System TiO2 Nanoparticles and N-Containing Compound
No full textThe purpose this research was to study the decomposition of phenol in water under the influence of UV radiation in the presence of nanoparticles TiO2 and methyl-3-amicrotonate. The photochemical decomposition of phenol in the presence of UV in a system of TiO2+N containing substances was carried out. The TiO2 nanoparticles used in the reaction had a size from 10 to 30 nm and belonged to the rutile phase. Nano-TiO2 was studied by X-ray diffraction, TEM and SEM methods. All the XRD peaks were well-defined and corresponded to rutile phase TiO2. From the line broadening of the (101) diffraction peak by Scherrer’s method, the average crystal size TiO2 is about 10.3. The specific surface areas for TiO2 is 159.6 m2/g. X-ray structure analysis Fig of the studied nanocomposite materials were recorded on the Rigaku Mini Flex 600s powder diffractometer. X-ray tube with copper anode (Cu-Kα radiation, 30 kV and mA) was used to draw the diffraction specters at room temperature. At 2θ = 20°- 80° with discrete growth mode these specters were obtained as Δ2θ = 0.05° and the exposure time was τ =5 seconds. The photochemical process lasted 1 hour using a very small amount of white powder and 0.05 gr of TiO2 nanoparticles synthesized by the sol-gel method and N-containing substance. For the process 1 mgL-1of phenol solution was used. The process was monitored with a spectrophotometer “Varian Cary 50”. After the photochemical decomposition of phenol, the reaction product was analyzed on an Agilent 6980N/5975 by the method GC-MSD. The goal was to determine the percentage of photochemical decomposition of phenol in TiO2+N system and 60% decomposition of phenol was defined
Synthesis, Structural Investigations, DNA/BSA Interactions, Molecular Docking Studies, and Anticancer Activity of a New 1,4-Disubstituted 1,2,3-Triazole Derivative
No full textWe report herein a new 1,2,3-triazole derivative, namely, 4-((1-(3,4-dichlorophenyl)-1H-1,2,3-triazol-4-yl)methoxy)-2-hydroxybenzaldehyde, which was synthesized by copper(I)-catalyzed azide-alkyne cycloaddition (CuAAC). The structure of the compound was analyzed using Fourier transform infrared spectroscopy (FTIR), 1H NMR, 13C NMR, UV-vis, and elemental analyses. Moreover, X-ray crystallography studies demonstrated that the compound adapted a monoclinic crystal system with the P21/c space group. The dominant interactions formed in the crystal packing were found to be hydrogen bonding and van der Waals interactions according to Hirshfeld surface (HS) analysis. The volume of the crystal voids and the percentage of free spaces in the unit cell were calculated as 152.10 Å3 and 9.80%, respectively. The evaluation of energy frameworks showed that stabilization of the compound was dominated by dispersion energy contributions. Both in vitro and in silico investigations on the DNA/bovine serum albumin (BSA) binding activity of the compound showed that the CT-DNA binding activity of the compound was mediated via intercalation and BSA binding activity was mediated via both polar and hydrophobic interactions. The anticancer activity of the compound was also tested by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay using human cell lines including MDA-MB-231, LNCaP, Caco-2, and HEK-293. The compound exhibited more cytotoxic activity than cisplatin and etoposide on Caco-2 cancer cell lines with an IC50 value of 16.63 ± 0.27 μM after 48 h. Annexin V suggests the induction of cell death by apoptosis. Compound 3 significantly increased the loss of mitochondrial membrane potential (MMP) levels in Caco-2 cells, and the reactive oxygen species (ROS) assay proved that compound 3 could induce apoptosis by ROS generation
Detailed thermodynamic analysis of the boiler-bubble pump region of a diffusion absorption refrigeration system: experimental and numerical study
No full textGlobal warming, inadequate natural sources and an energy crisis are significant concerns in this century. In this context, it has become important to use efficient energy technologies and reduce energy consumption in the cooling industry. In recent years, Diffusion Absorption Refrigeration (DAR) systems have been widely studied as good alternatives to vapor compression cooling systems. In this article, the heat exchanger part located in the boiler-bubble pump region of the DAR system was numerically modeled to determine its behavior. In addition to modeling, five different working fluids were utilized in the DAR system experimentally. The first test was performed utilizing 25% NH3-H2O by mass without nanoparticles. The other four tests were repeated by adding 1% and 2% (by weight) zinc oxide (ZnO) and graphene oxide (GO) nanoparticles into 25% NH3-H2O solution, respectively. The numerically obtained results showed no significant increase in the use of ZnO nanoparticles by 1% or 2%. It was seen that GO nanoparticles made a more meaningful difference in the heat transfer increment than the ZnO nanoparticles. Furthermore, experimental results showed that the utilization of nanoparticles in a 25% NH3-H2O solution assists in disappearing refrigerant. Generally, it was determined that adding nanoparticles to the base fluid eliminates the effects of temperature changes in the system
Characterization of 1–3 piezocomposites from PNN-PZT piezoceramics
No full textPiezocomposite materials combine best properties of components while minimizing their disadvantages to provide desired properties. This study reports on piezocomposites with 1–3 connectivity prepared from 0.5Pb(Ni1/3Nb2/3)O3-0.5Pb(Zr0.3Ti0.7)O3 (0.5PNN-0.5PZT) fibers and polyurethane matrix. The PNN-PZT powder was synthesized by solid-state reaction method. PNN-PZT green fibers were drawn using the alginate gelation method. Dense sintered fibers with 500–800 µm diameter were embedded in an ordered arrangement in a polyurethane passive matrix. Structural, electrical and electroacoustic properties of PNN-PZT piezocomposite and bulk ceramic were both reported. Bulk PNN-PZT ceramics were found to have properties that are superior than the commercial soft PZT counterparts. The maximum TVR value was measured as 142.5 dB at 444 kHz for the piezocomposite, corresponding to the thickness mode resonance. The FFVS response with 3 dB variation had an average FFVS value of − 210 dB between 250 and 450 kHz band for the piezocomposite
Tuning the magnetic and magnetocaloric properties of a compound via mixing (1–x).La0.67Ca0.33MnO3 +x.La0.67Sr0.33MnO3 (x = 0, 0.25, 0.50, 0.75, 1): Composite materials or composite compounds?
No full textThis study aims to optimize the magnetic and magnetocaloric properties of composite materials (or compounds) produced by mixing different ratios of two manganite compounds having different structural, magnetic, and magnetocaloric properties. The parent compounds were prepared using the sol–gel production method and the ultrasonic bath mixing technique was involved to prepare desired composite materials. SEM analyses revealed that the parents and composite materials have the same surface morphologies except for their grain sizes. EDS analyses were performed to identify the possible/candidate phases in the composite materials. These candidate phases are involved in refining XRD data. The fact that the Curie temperatures (TC) of the composite materials were found to be much higher than those of the parent compounds was another proof that composite compounds were obtained instead of composite materials by using the ultrasonic bath mixing technique. Although the TC of the composite compounds was higher than those of the parent compounds, the maximum magnetic entropy values were found to vary between the maximum magnetic entropy valuesof the parent compounds
Design and experimental analysis of a parallel-flow photovoltaic-thermal air collector with finned latent heat thermal energy storage unit
No full textIn this work, it is aimed to improve the performance of a photovoltaic-thermal (PVT) air collector using finned latent heat thermal energy storage unit. In this regard, four different types of parallel-flow PVT (PPVT) systems have been designed, manufactured and tested including a conventional PPVT, a PPVT with paraffin-based thermal energy storage unit, a PPVT with 3-finned storage unit and a PPVT with 6-finned storage unit. A parallel-flow collector geometry has been designed to convey excess heat from both surfaces of the photovoltaic panel in the systems. Moreover, the effect of increasing the number of fins in the storage system in the PPVT on the performance has been analyzed within the scope of this work and the developed systems have been tested simultaneously. According to the experimentally obtained findings, overall efficiency value of the PPVT was improved from 55.83% to 76.79% using thermal energy storage with 6-fins. The performance ratio and sustainability index values were obtained between 0.64-0.76 and 1.0277–1.0474, respectively. Enviro-economic analysis has been performed and payback periods of the systems were attained between 0.991 and 1.146 years. Also, employing 6-finned storage unit in the PPVT upgraded the annual carbon dioxide savings as 33.71% in comparison to the unmodified PPVT