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Enterobacter sp. 3TP2A isolated from a petroleum station was found to produce a novel, highly inducible mesophilic intracellular β -galactosidase in the presence of lactose up to 76.5 U mg-1. The enzyme was purified to 17.3-fold after gel permeation chromatography with a yield of approximately 11 %. The optimum pH and temperature values of the purified enzyme were found to be 8.0–9.0 and 35 °C, respectively. The molecular weight of the enzyme was approx. 60 kDa with a single band by both SDS-PAGE and native-PAGE, and estimated by gel filtration chromatography. The enzyme was inhibited by Zn2+ and EDTA, while Cu2+ had strong inhibitory effect even at low concentrations. Activation by Mg2+ and inhibition by EDTA show that the enzyme is metal-dependent or a metalloenzyme. The enzyme was slightly activated by 2-mer­captoethanol, while slightly inhibited by iodoacetamide. On the other hand, PCMB inhibited the enzymatic activity to a great extent, whereas it was com­pletely inhibited by N -ethylmaleimide. The V max and K m values were calcul­ated as 0.701 μmol min-1 and 0.104 mM, respectively. The results indicated that the β -galactosidase Enterobacter sp. 3TP2A might well be a good candi­date for use in biotechnology, particularly in the area of environment and health.

Irish-type Zn-Pb deposits are important global sources of zinc, but despite a fundamental understanding of ore genesis within the Irish orefield, a detailed understanding of fluid migration and chemical evolution pathways related to sulfide and carbonate precipitation is lacking. We present the first petrographic, paragenetically constrained sulfur isotope and mineral chemistry study of mineralization at the Island Pod orebody, Lisheen deposit. The Island Pod orebody comprises high-grade mineralization that is less deformed than elsewhere in the Irish orefield. Consequently, studies of the Island Pod orebody and its mineralization provide information on the evolving nature of hydrothermal fluids involved in ore deposition. The Island Pod orebody consists almost exclusively of pyrite, sphalerite, and galena, with several stages of calcite and dolomite precipitation. Pre-ore, diagenetic pyrite is commonly overgrown by early main ore-stage pyrite, with both phases frequently replaced by main ore-stage sphalerite. In many cases, early main ore-stage pyrite is texturally zoned and exhibits chemical zoning patterns, reflecting that episodic influxes of hydrothermal fluids contained variable concentrations of As, Co, Ni, and Tl. The main ore stage was dominated by the formation of sphalerite and galena from mineralizing fluids that were depleted in these trace elements (e.g., As, Co, Tl) compared to the early main ore stage. Sulfur isotope analysis reveals four distinctive but slightly overlapping isotopic groupings, corresponding to different mineral and paragenetic stages: (1) δ34S values range from –47.7 to –30.7‰, associated with diagenetic pyrite; (2) δ34S values range from –34.3 to –14.7‰, related to early main ore-stage pyrite; (3) δ34S values range from –15.5 to +1.7‰, corresponding to main ore-stage sphalerite; and (4) δ34S values range from –11.1 to +17.4‰, associated with galena. Large variations in S isotope composition are common at intragrain and at other small spatial scales. The textures, paragenetic sequence, and ranges in δ34S values are consistent with hydrothermal sulfide deposition where the fluids containing bacteriogenic sulfide mixed with metal-bearing fluids. Replacement and remobilization from other Lisheen orebodies may have contributed to some of the higher sulfur isotope ratios observed in the Island Pod orebody. The excellent preservation of sulfide textures in the Island Pod orebody observed during this study demonstrates that it is an ideal location to study hydrothermal fluid evolution, including episodic fluid flow, mixing, precipitation, and compositional variations during the early main ore stage. In other Irish Zn-Pb orebodies, these early-ore textures are often obscured due to more complex dissolution and replacement processes, making interpretation of the early hydrothermal activity challenging. Consequently, the petrographic, mineral chemistry, and sulfur isotope studies of the Island Pod orebody presented here contribute to an enhanced understanding of ore-forming processes in similar deposits, where mineralization is often associated with more complex deformation or repeated pulses of hydrothermal activity.

Pollutant emissions are one of the major problems for the World. In this regard, researchers focus on the studies on emission reduction. Hydrogen is an alternative solution for this problem. Hydrogen produces only water as a result of combustion with oxygen. Therefore, this study examines the combustion stability and emissions of a high hydrogen content fuel mixture. The fuel mixture containing 45% H-2 by volume was supported with 5% CH4 in order to provide stable combustion. In addition, in order to reduce the instabilities caused by the high laminar burning rate of hydrogen, it was diluted with 50% CO2 which equal volume with the fuel mixture. After the fuel mixture containing 45% H-2 -5% CH4 -50% CO2 was burned with air containing 21% O-2, enrichment was applied at the rates of 24% and 27% O-2. The flame that contains different oxygen ratios was acoustically forced through the speakers around the combustion chamber. The stability data, dynamic pressure, and light intensity fluctuation of the flame were recorded under different acoustic resonance frequencies (110 Hz, 190 Hz, 260 Hz). In this way, the oxygen enrichment performance and flame characteristics of hydrogen in a premixed burner, which is promising in zero-emission studies, were investigated. As a result, when the combustion condition of 21% O-2 and 24% O-2 ratios are compared, the instability increased slightly from 801 Pa to 887 Pa, respectively. However, at 27% O-2, the flame could not perform a stable combustion under acoustic enforcement. The flame flashbacked with a dynamic pressure fluctuation of 1577 Pa under an acoustic frequency of 110 Hz. In addition, it was observed that CO emissions have decreased with the increase in oxygen enrichment rate. CO emission measured at 1080 ppm at 21% O-2 decreased to 542 ppm and 276 ppm respectively at 24% and 27% oxygen enrichment levels. While NOx emission was measured at 10 ppm in the case of combustion with air, it was observed that decreased to 4 ppm at the rate of 27% O-2.(C) 2021 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.

ABS TRACT Synthetic gases attract the attention of researchers due to the increase in energy demand. H2 and CO gases are the main components of synthetic gases. In this study, three different gas mixtures were tested according to their H2/CO (3, 1.5, 0.5) ratios. Thermal power (3 kW), swirl number (1) and equivalence ratio (0.7) kept constants for all experiments. Three different oxygen ratios selected for the oxygen enrichment experiments. First, the gas mixture was burned with standard air. After that, the oxygen concentration in the oxidizer was raised to 23 % and 25 % for examining the effect of oxygen enrichment. The stability results showed that an increase of hydrogen content in the synthetic gas mixtures caused decreasing in the oxygen enrichment limit. The mixture, which can be enriched up to 25.8 % O2 while the H2/CO ratios are 0.5, can be increased up to 25.2 % O2 at a medium H2/ CO ratio (1.5). In the case where the H2/CO ratio was increased to the high level (3) by increasing the hydrogen level, the oxygen enrichment limit decreased to 24.1 %. A stable flame did not occur after these oxygen enrichment values. In addition, dynamic pressure data were recorded for all mixtures under external acoustic enforcement. Increases in the hydrogen and oxygen ratio at the same time caused the flame instabilities. Thus, the flame extinguished under acoustic enforcement. In addition to these results mentioned, the emission values showed that oxygen enrichment caused the decrease in CO emissions but the increase of NOx values for all synthetic gas mixtures.(c) 2021 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.

Objective: The aim of our study was to assess the possible short-term effects of topical and oral eugenol on the suppression of experimentally developed myringosclerosis (MS). Methods: Four groups of seven male Wistar albino rats were used in the study. The tympanic membranes (TMs) of all subjects were myringotomized, and group 1 was given no treatment (as control group), group 2 received saline, group 3 had received topical eugenol and group 4 received oral eugenol. Results: In macroscopic evaluation the control and saline groups showed much more MS compared to the topical and oral eugenol groups which had statistically significantly less changes (p

This study aimed to investigate the treatment of paint production industry (PPI) wastewater, which is characterized by low biodegradability and high concentrations of resistant organic matter, by persulfate enhanced electrocoagulation process (EC-PS). A regression quadratic model was developed to describe the removal of chemical oxygen demand (COD) and color number (CN) from PPI wastewater. The effects of independent variables (initial pH, PS dose, current density, and reaction time) on system responses and the interaction between the parameters were determined. Validation experiments were carried out under the optimum conditions determined by the quadratic model (initial pH: 5, PS dose: 5.6 g/L, current density: 21 mA/cm2, and reaction time: 35 min) and 64% COD and 98.1% CN removal were obtained. Pollutant removal efficiencies increased with the increase of PS dose, current density, and reaction time while the highest removal efficiencies were achieved at acidic pH values. The scavenging studies indicated that although the sulfate radicals were the dominant radical type, both hydroxyl and sulfate radicals were involved in the process. In the synergistic effect studies performed under optimum conditions, the highest reaction rate was obtained in the EC-PS process with a value of 0.074 1/min. Specific energy consumption under optimum conditions was calculated as 20.4 kWh/kg COD. The results of the study showed that the EC-PS is an effective process for the treatment of PPI wastewater and response surface methodology is an applicable technique for the optimization of the variables.

In this study, the intracellular β-galactosidases of Bacillus subtilis 4NK and Bacillus paralicheniformis 5NK isolated from Bingöl Binkap hot spring was partially purified and characterized. As a result of purification, the yield of the enzyme for B. subtilis 4NK was 85.2% and the purification fold was 2.8. The yield for B. paralicheniformis 5NK was 76.8% and the purification fold was 2.0. The optimum temperature of the enzyme was determined as 45 oC for B. subtilis 4NK and 55 oC for B. paralicheniformis 5NK and the optimum pH was 6.0 for both. In addition, in the thermal stability experiments even at the end of 120 min both enzymes were stable at 50 oC. It was determined that the partially purified enzyme activity increased in the presence of iodoacetamide and phenylmethylsulfonylfluoride for B. subtilis 4NK, dithiothreitol, N-ethylenemaleimide and phenylmethylsulfonylfluoride for B. paralicheniformis 5NK. The metals were found to activate the enzyme at low concentrations of Co2+, Cd2+ and Mn2+ for B. subtilis 4NK, Cu2+ and Cd2+ were found to inhibit the enzyme at high rates for B. paralicheniformis 5NK. Km and Vmax values for 4NK and 5NK, respectively; 23.80 mM, 1.978 μmol/min and 5.61 mM, 1.869 μmol/min.

Furfural removal by electrochemically activated peroxydisulfate (E-PS) and peroxymonosulfate (E-PMS) was investigated. The effect of different anodes was investigated for the electrochemical activation of oxidants. Box Behnken Design was applied to determine optimum operating conditions, which were determined as follows; PS concentration: 2.3 mM, applied current: 1.15 A, pH: 3.5, and reaction time: 118.3 min for E-PS process; PMS concentration: 1.8 mM, applied current: 1.05 A, pH: 3.3, and reaction time: 107.8 min for E-PMS process. The results of the study showed that the E-PMS process is more advantageous in terms of the chemical and electricity costs to be used.

The thermophilic amylase producing Anoxybacillus ayderensis FMB1 was isolated from Sorgun Hot Spring in Turkey. In order to obtain improved production of the enzyme for cost-effective process, opti...

In this study, a nickel aluminide coating was obtained on CMSX-4 via a chemical vapor aluminizing (CVA) technique. The CVA coating process was carried out for 4 and 6 hours at 1070°C to examine the effects of CVA process time on the properties of the nickel aluminide coating. Heat treatment processes were subsequently applied to nickel aluminide-coated samples for 2 hours at 1050 and 1100°C to examine the effects of heat treatment temperature on the coating. The characterization of coated samples was carried out via SEM, EDS, XRD, GDOES and Vickers hardness analyses. The results showed that the increment in CVA process time induced an increase in inter-diffusion zone thickness due to the increased Ni outward diffusion from the CMSX-4 substrate. The additive layer of the four-hour CVA coating is composed of the δ-Ni2Al3 phase due to the dominance of Al inward diffusion. The phase transformation from δ-Ni2Al3 to the desired β-NiAl was observed in four-hour CVA coating structure subsequent to the heat treatment processes. However, the additive layer of six-hour CVA coating consists of the β-NiAl phase both before and after the heat treatment processes. Heat treatment processes increase the thickness of the coatings because they provide increased Al inward and Ni outward diffusion. The results of the Vickers hardness tests demonstrated that the heat treatment processes cause a decrease in the hardness of the additive layer of the four-hour CVA coating from 754 to 578 HV for heat treatment at 1050°C, and to 522 HV for heat treatment at 1100°C due to phase transformation phenomena.

Oxytetracycline (OTC) is a broad-spectrum antibiotic that resists biodegradation and poses a risk to the ecosystem. This study investigated the degradation of OTC by heat-activated peroxydisulfate (PDS) and peroxymonosulfate (PMS) processes. Response surface methodology (RSM) was used to evaluate the effect of process parameters, namely initial pH, oxidant concentration, temperature, and reaction time on the OTC removal efficiency. According to the results of the RSM models, all four independent variables were significant for both PDS and PMS processes. The optimum process parameters for the heat-activated PDS process were pH 8.9, PDS concentration 3.9 mM, temperature 72.9°C, and reaction time 26.5 min. For the heat-activated PMS process, optimum conditions were pH 9.0, PMS concentration 4.0 mM, temperature 75.0°C, and reaction time 20.0 min. The predicted OTC removal efficiencies for the PDS and PMS processes were 89.7% and 84.0%, respectively. As a result of the validation experiments conducted at optimum conditions, the obtained OTC removal efficiencies for the PDS and PMS processes were 87.6 ± 4.2 and 80.2± 4.6, respectively. PDS process has higher kinetic constants at all pH values than the PMS process. Both processes were effective in OTC removal from aqueous solution and RSM was efficient in process optimization.

Objective: Methotrexate (MTX) is a commonly used chemotherapeutic agent in clinical oncology practice and in treatment of autoimmune diseases. The major side effect during treatment is mucositis. Recently published studies reported that this effect may be due to direct intestinal epithelial injury and disturbance of intestinal microbiota. In this study, we aimed to characterize the intestinal histological changes caused by MTX and to investigate the effects and safety of Sildenafil and probiotic Bacillus clausii on intestinal mucositis in a rat model. Materials and Methods: The rats were divided in 4 groups; Group1(n=8) received MTX + B. clausii, Group 2 (n=8) received only MTX, Group3 (n=8) received MTX + Sildenafil and Group 4 (n=7) was served as control (received no treatment). Results: The rate of villus atrophy, villous fusion and erosion in the MTX + B. clausii group were found to be statistically significantly lower than in the MTX group and the MTX + Sildenafil group. Conclusion: The study demonstrated the effect of B. clausii on repairing of intestinal mucosa after MTX-treatment. The better understanding of the effects of probiotics on intestinal mucosal protection may lead to new therapeutic approaches in chemotherapy-induced mucositis.

In this study, the removal of UV254, phenol, and calcium from paper industry wastewater by persulfate oxidation was investigated. Fe2+ addition and heat application methods were used for persulfate...

In this study, the treatment of nanofiltration (NF) concentrate from a landfill leachate treatment plant through the electrooxidation (EO) process was investigated. Experimental studies were conducted in a batch reactor equipped with multi-metal oxide/TiO2 doped Ti anode and Pt doped Ti cathode. Persulfate was added as the oxidant and the performance of Fe0, Fe2+, and Fe3+ species as catalysts for persulfate activation was compared. Kinetic studies were carried out for chemical oxygen demand (COD) removal from leachate NF concentrate. Maximum COD removal efficiency was obtained by the EO process in which persulfate was added as the oxidant and Fe2+ was used as the catalyst for persulfate activation. Optimum values of the process variables (pH 5, current 2 A, Fe2+ dose 12 mM and persulfate dose: 60 mM) were determined. The COD removal was 77.1% under optimum conditions. The overall COD removal mechanism is well fitted with the pseudo-first-order and second-order kinetic models with R2 values of > 0.80 under all applied current values. Specific energy consumption calculated for optimum conditions were 73.4 kWh/m3 and 14.3 kWh/kg COD. The EO process assisted with Fe2+ activated persulfate can be evaluated as an efficient treatment method for leachate NF concentrate treatment.

BACKGROUND: In many studies, vitamin D has been found to be low in COVID-19 patients. In this study, we aimed to investigate the relationship between clinical course and inhospital mortality with parenteral administration of high-dose vitamin D3 within the first 24 h of admission to patients who were hospitalized in the intensive care unit (ICU) because of COVID-19 with vitamin D deficiency. METHODS: This study included 175 COVID-19 patients with vitamin D deficiency [25(OH) D

In this study, a series of trinitroaniline derivatives (TNA1-8) were synthesized and investigated as potential antitumor agents for enzyme-prodrug therapy. Enzymatic efficiency of Ssap-NtrB on prodrug candidates was determined with HPLC analysis and kinetic studies. The anti-proliferative properties of compounds were determined against four cancer cell lines (Hep3B, PC3, HT-29, and Saos-2) and a healthy cell line (HUVEC) via MTT assay. Intracellular and extracellular prodrug-enzyme treatments were carried out on Hep3B cells. Herewith, the expression of the Ssap-NtrB gene was confirmed with this study. IC50 values of piperidine and 1,3-cyclohexyl derivatives (TNA4 and TNA7) were identified as 1.724 nM and 1.640 nM at extracellular conditions. In intracellular conditions, it was determined as 0.293 mu M and 0.393 mu M, respectively. In summary, 2,4,6-trinitroaniline derivatives, especially compounds TNA4 and TNA7 might be used as prodrug candidates along with Ssap-NtrB for hepatocellular carcinoma therapy and the development of new prodrugs at cancer treatments.

Although Crimean-Congo hemorrhagic fever (CCHF) is mild and self-limited in children, some patients may develop excessive bleeding, massive liver necrosis, and multiple organ failure associated with secondary hemophagocytic lymphohistiocytosis (HLH) induced by cytokine storm. Treatment of CCHF is mainly symptomatic and supportive. The efficacy of ribavirin, which is the only antiviral drug in the treatment of CCHF, remains controversial. Although therapeutic plasma exchange (TPE) has been shown to beneficial in small case series with primary and secondary HLH, there is no pediatric patient with HLH secondary to CCHF treated with TPE in the literature. In this report, we describe the first pediatric patient who was successfully recovered from HLH secondary to CCHF with ribavirin, intravenous immunoglobulin, and TPE.

The present study investigates the toxicity of the herbicide tribenuron methyl (TBM) as an anthropogenic agent and ammonia as an abiotic factor on Daphnia magna at environmentally relevant concentrations. These stressors may coexist in surface waters in agricultural regions. To achieve this objective, D. magna were exposed to TBM at a nominal concentration of 0.81 μg/L in association with a low ammonia (LA) concentration of 0.65 mg/L and a high ammonia (HA) concentration of 1.61 mg/L in acute toxicity tests of 96-h duration and chronic toxicity tests of 21-day duration. The D. magna also were exposed to TBM, HA, and LA singly. The D. magna were analysed for various biomarkers of sublethal toxicity. Glutathione peroxidase (GPx), glutathione S-transferase (GST), cholinesterase (ChE) enzyme activities, and levels of thiobarbituric acid reactive substances (TBARS) and total protein were determined spectrophotometrically. Mitochondrial membrane potential (MMP) was analysed by microscopy with fluorescence staining. Cytochrome c and 5' AMP-activated protein kinase (AMPK) were analysed by Western blotting. Morphometric properties were examined microscopically. This is the first study in which AMPK, an indicator of intracellular energy, was measured in D. magna. GST and ChE enzyme activities and TBARS and total protein levels did not change during acute exposures (i.e., 96 h) in all treatments. GPx activity increased in D. magna from the HA + TBM treatment compared with single-exposure groups. The level of cytochrome c protein was elevated in D. magna from the LA and LA + TBM treatments. AMPK protein levels increased in all treatments with daphnids, except in the LA group. MMP was depolarised in D. magna from all treatments, whereas the most notable change was observed in HA + TBM mixture group in chronic exposures. The results show that GST and ChE may not be sensitive biomarkers for evaluating the sublethal toxic effects to D. magna exposed to environmentally relevant concentrations of ammonia and TBM. Acute and chronic exposure to ammonia and TBM probably caused an energetic crisis in D. magna. Therefore, AMPK and MMP are promising biomarkers for these toxicants.

The sources and fate of antimony (Sb) and arsenic (As) in water resources around antimonite (a.k.a. stibnite) deposits is of great concern due to their adverse effects on the environment and human ...

The aim of the current study was to investigate the pharmacological activity of glabridin on the isolated human saphenous vein (SV) and explore the underlying mechanisms. Samples of patients' SVs were removed during bypass surgery, and 4-mm lengths of the vessels were placed in Krebs solution at +4°C and hung in an isolated organ bath to assess their contraction/relaxation responses. The contraction/relaxation responses were recorded to observe if the cyclic guanosine monophosphate (cGMP)/protein kinase G (PKG) pathway mediates the relaxant effect of glabridin after treatment with blockers like ODQ (a guanylate cyclase inhibitor), KT5823 (a PKG inhibitor), isobutylmethylxanthine [IBMX, a phosphodiesterase (PDE) inhibitor], and cantharidin [Cant, a myosin light-chain phosphatase (MLCP) inhibitor]. Moreover, nitric oxide (NO), cGMP, and PKG levels in SV tissues were determined by ELISA after incubation with glabridin, N(ω)-nitro-L-arginine methyl ester (L-Name, a NO synthetase inhibitor), phenylephrine (PE), ODQ, IBMX, and KT5823. The results showed that glabridin relaxed the vascular smooth muscle of human SV pretreated with PE in a dose-dependent manner, which was independent of the endothelium. The vasorelaxant effect of glabridin was only inhibited by iberiotoxin (IbTX), Cant, and KT5823. Glabridin increased cGMP and PKG levels in SV homogenates, whereas it did not alter the NO level. The enhancing effects of cGMP and PKG levels by glabridin were abolished by ODQ and KT5823. In conclusion, glabridin has a vasorelaxant effect, which is associated with the activation of BKCa channels and inhibition of PDE.

During ethanol fermentation, ethanol accumulates in the medium and becomes a significant stress factor for yeast. Trehalose and glycogen are major carbohydrate storages and presumably protect cells from such stress conditions. In this study, batch cultivations of wild and adapted Saccharomyces cerevisiae were performed to evaluate the fermentation kinetics and carbohydrate storages, interrelatedly. Trehalose and glycogen were determined by both High Performance Liquid Chromatography (HPLC) and Fourier Transform-Infrared (FT-IR) spectroscopy for comparison. The obtained maximum trehalose and glycogen (7.5 and 10.5 %) contents of the adapted strain was remarkably higher compared to the wild strain (5 and 6.5 %). The adapted S. cerevisiae displayed an enhanced fermentation stresses coping ability resulting in a higher ethanol productivity (2.03 vs 1.65 g ethanol/h) as well as higher ethanol titer (7.7 vs 6.4 %). This study contributes to the understanding of the cellular response of S. cerevisiae cells to fermentation stresses in relation to culture history together with the evaluation of fermentation performance, as well as the process kinetics. This study also confirms that FT-IR spectroscopy of whole S. cerevisiae cells for determination of storage compounds without pretreatment has valuable advantages compared to HPLC with intensive sample handling.

Copper ferrite/copper oxide (CuFe2O4/CuO) nanocomposites contents were prepared by using co-precipitation and sol-gel methods. The alternating current impedance and permittivity parameters of the s...

Bu çalışmada, suda çözünür karbonhidrat (SÇK) ve tanen bakımından zengin Gladiçya (Gleditsia triacanthos) meyvesinin, çayırotu silajı yapımında silaj katkı maddesi olarak kullanım olanakları araştırılmıştır. Gladiçya meyvesi, silajların kompozisyonlarına, fermentasyon parametrelerine, in vitro gaz üretim parametrelerine, in vitro organik madde sindirim derecelerine (İVOMSD) ve metabolik enerji içeriklerine (ME) önemli derecede etki etmiştir. Gladiçya meyvesinin silajlara katılma oranına bağlı olarak oluşan silajların kuru madde içeriği (KM), Fleig skorları (FS), in vitro gaz üretimleri, organik madde sindirim dereceleri (OMSD), metabolik enerji içerikleri ve kuru madde sindirim dereceleri (KMSD) önemli derecede artarken, kül içerikleri (HK), asit deterjan fiber (ADF), nötral deterjan fiber (NDF) ve ham protein içerikleri (HP) azalmıştır. Kontrol grubuyla karşılaştırıldığında, %6 oranında Gladiçya meyvesi ilavesi çayırotu silajının amonyak içerikleri %46 oranında, pH’sını ise %13,12 oranında düşürmüştür. Kontrol grubuna göre, %6 oranında Gladiçya meyvesi ilave edilen çayırotu silajının Fleig Skoru 56,0’den 90,46’ya yükselmiştir. Kontrol grubuyla karşılaştırıldığında, %6 oranında Gladiçya meyvesi ilavesi çayırotu silajının ME içeriğini %8,76 oranında, OMSD ise %11,87 oranında kuru madde sindirim derecesini %20,28 artırmıştır. Sonuç olarak; daha kaliteli çayırotu silajı elde etmek için taze çayırotuna en az %3 oranında Gladiçya meyvesi katılması tavsiye edilebilir., In the current study honey locust (Gleditsia triacanthos) pods which is rich in water soluble carbohydrate (WSC) and tannin, was used as a silage additive for grass plant. Honey locust pods had a significant effect on the chemical composition, fermentation parameters, in vitro gas production parameters, in vitro organic matter digestibility (OMD) and metabolisable energy (ME) content of grass silage. Although dry matter content, Fleig score, in vitro gas production, organic matter digestibility (OMD), metabolisable energy (ME) and dry matter digestibility (DMD) of the resultant grass silage increased, crude ash, acid detergent fiber, neutral detergent fiber and crude protein (CP) contents decreased with increasing level of honey locust pods. The inclusion of honey locust pods at %6 into grass material resulted in a decrease in % 46 of the ammonia concentration and13.12% of pH respectively, when compared with control group of grass silage. On the other hand, the inclusion of honey locust pods at 6% into grass material resulted in an increase in 8.76% of the metabolisable energy, 11.87% of organic matter digestibility and 20.28% of dry matter digestibility respectively, when compared with control group of grass silage. In addition, the inclusion of honey locust pods at %6 into grass material resulted in an increase in Fleig score from 56.0 to 90.46. It can be concluded that, at least, 3% of ground honey locust pods on fresh basis should be included into grass forage to obtain high quality grass silage.

Erdogan, Erman/0000-0003-2566-3284 In recent years, ZnO films are among the preferred transparent conductive oxides because of their advantageous properties such as being nontoxic, low cost and abundant in nature. In this study, undoped and Nd doped ZnO films were produced on microscope glass substrates with the spray pyrolysis technique, which is an economical and easily applicable method, at a substrate temperature of 380 degrees C. From the X-ray diffraction patterns, the crystal structures of all films have a preferential orientation (002). It is observed from the XRD peak intensities that the ZnO film with a 3% Nd doping has a (100) preferential orientation. The increase in Nd dopant concentration is the reason for changing the preferred direction of the grains completely. The average particle sizes of the films were calculated using Scherrer and Williamson-Hall method. It was determined that the film with 2% Nd doped crystallized better than other films and the largest particle size belongs to this film. The transmittance spectra of Nd doped ZnO films were taken using a UV-Vis spectrophotometer. The optical transmittance spectrum of the films shows that in the visible region, all films have a value of over 90%. Optical band gap values were calculated using these spectra. According to the results obtained, it was determined that the optical band value of the ZnO film decreased first with the Nd contribution, and started to increase when the amount of dopant increased. The surface morphology of the films was analyzed by optical profilometer and surface roughness values were determined. It indicates that the films grown on the glass substrate, as observed in the XRD analysis of the films, consist of nanoscale particles. It has been observed that the surface roughness of the films varies with the increasing amount of Nd. To investigate the surface conditions of the films, the scanned electron microscopy (SEM) images of the obtained films were taken. From the SEM images, it was observed that the surfaces of the films were similar to each other, were nonporous and homogeneous. With this study, the effect of Nd doping on structural, optical and superficial properties of ZnO films was investigated and it was determined that Nd doping of ZnO films were suitable materials for optoelectronic applications.

In the present study, the effect of an La alloying element with different quantities (1, 3 and 5 wt.-%) on the microstructure, mechanical and dry sliding wear properties of Mg- 3Al-3Sn-3Sb alloy was investigated. The wear tests were done on the alloys using pin on-disk equipment against a 4140 steel disc as counterpart under three different sliding velocities of 0.3, 0.6 and 1.2 ms-1 and four different loads of 5, 10, 20 and 40 N. The microstructural results showed that the new intermetallic phases (La5Sn3 and LaSnSb2) were formed with addition of La to the main alloy. Also, it was observed that the hardness of the Mg-3Al-3Sn-3Sb alloy was raised with increasing La addition. Furthermore, the tensile properties of the Mg-3Al-3Sn-3Sb alloy improved with rising La content at room and elevated temperature. The wear rates of the alloys increase with increasing of the sliding speed and load. In addition to this, the wear rate of the Mg-3Al-3Sn-3Sb alloy was found to be higher than that of the La content alloys for all test conditions.

In this study, the molecular structure, vibrational spectroscopic and electronic properties of Palmitoleic Acid (cis-9-Hexadecenoic acid, C16:1, POA) were investigated using the Gaussian 09 package program at DFT/B3LYP/6-311++G(d,p) level. Since the crystal structure of POA has not been determined yet, the optimized geometric parameters (bond length, bond angles and dihedral angles) were compared with experimental geometric parameters of Oleic acid (OA) which is isomorphous to the POA. The harmonic vibrational frequencies of the POA were calculated and compared with the experimental vibrational frequencies which obtained from the literature. The assignments of the vibrational frequencies were performed by potential energy distribution (PED) analysis by using VEDA 4 program. The calculated structural parameters and vibrational frequencies of POA are in good agreement with the experimental data. The electronic properties of the molecule were defined on the basis of the highest occupied molecular orbital (HOMO) and the lowest unoccupied molecular orbital (LUMO). The high energy gap between HOMO-LUMO energies shows that the molecule has chemical stability and low reactivity. Molecular electrostatic potential (MEP) surface map, mulliken atomic charges and quantum chemical descriptors such as hardness, softness, electronegativity, chemical potential, ionization potential, electron affinity, electrophilic index, dipole moment were calculated to determine interaction sides in the molecule. Besides, the thermodynamic properties such as heat capacity, entropy, and enthalpy of POA at different temperatures were calculated in gas phase. All thermodynamic parameters increased with increasing temperature., Bu çalışmada, Palmitoleik Asit (cis-9-Hekzadekanoik asit, C16:1, POA) ’in moleküler yapısı, titreşimsel spektroskopik ve elektronik özellikleri Gaussian 09 paket programı kullanılarak DFT/B3LYP/6-311++G(d,p) seviyesinde incelenmiştir. POA’ nın kristal yapısının henüz belirlenmediğinden, optimize edilmiş geometrik parametreleri (bağ uzunluğu, bağ açıları ve dihedral açılar), POA’ ya izomorf olan Oleik asidin (OA) deneysel geometrik parametreleriyle karşılaştırılmıştır.POA’ nın harmonik titreşim frekansları hesaplanmış ve literatürden elde edilen deneysel titreşim frekansları ile karşılaştırılmıştır. Titreşim frekanslarının işaretlemeleri, VEDA 4 programı kullanılarak potansiyel enerji dağılımı (PED) analizi ile gerçekleştirilmiştir. POA’ nın hesaplanan yapısal parametreleri ve titreşim frekansları deneysel verilerle uyumludur. Molekülün elektronik özellikleri, en yüksek dolu moleküler orbital (HOMO) ve en düşük boş moleküler orbital (LUMO) temeline dayanılarak belirlenmiştir. HOMO-LUMO enerjileri arasındaki yüksek enerji aralığı molekülün kimyasal kararlılığa ve düşük reaktiviteye sahip olduğunu gösterir. Moleküler elektrostatik potansiyel (MEP) yüzey haritası, mulliken atomik yükleri ve sertlik, yumuşaklık, elektronegatiflik, kimyasal potansiyel, iyonizasyon potansiyeli, elektron afinitesi, elektrofilik indeks, dipol moment gibi kuantum kimyasal tanımlayıcıları moleküldeki etkileşim bölgelerini belirlemek için hesaplanmıştır. Ayrıca, POA’ nın ısı kapasitesi, entropi ve entalpi gibi termodinamik özellikleri farklı sıcaklıklarda hesaplanmıştır. Tüm termodinamik parametreler, artan sıcaklıkla birlikte artmıştır.

In this study, the pKa value of vemurafenib was determined by the dependence of the retention factor on the pH of the mobile phase. The change of pKa in the different acetonitrile fraction ranging between 57.5 and 62.5% (v/v) was studied by using an LC-UV method. Additionally, a simple, reliable, and rapid UPLC method has been developed for the determination of vemurafenib in human urine. Efavirenz was used as an internal standart. For vemurafenib and efavirenz, selectivity factors were found as 1.204. The asymmetry and capacity factors were obtained as 1.100 and 7.532 for vemurafenib. Vemurafenib was exposed to thermal, photolytic, hydrolytic, and oxidative stress conditions, and the stressed samples were detected by LC/MS/MS method.

© 2021, The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.First time in this study, organic@inorganic hybrid copper nanoflowers (Cu NFs) were synthesized by using cherry stem extract as an organic component and Cu2+ ion as an inorganic component. For this purpose, cherry stalk extracts were obtained by using ethanol and water solvents. Cu NFs were synthesized in different amounts of extract (100–1000 µl) and under various pH (7.4–9) conditions. The morphologies of the synthesized Cu NFs were evaluated by field emission scanning electron microscope (FE-SEM). The functional groups in the cherry stem extract, which play an active role for the synthesis process, and the crystal structure of NFs were investigated by Fourier transform ınfrared spectroscopy and X-ray diffraction techniques, respectively. It has been determined by the FE-SEM analysis that ethanol and water based cherry stem extracts are suitable for Cu NFs synthesis in a wide range of pH (7.4–9). This data is crucial for overcoming important limitations for NF synthesis, such as narrow-range medium pH. The catalytic, antioxidant, and antimicrobial activities of Cu NFs were evaluated. It was revealed that Cu NFs have catalytic, antioxidant, and antimicrobial activities. It is recommended that, cherry stem extract and different inorganic components are functional to synthesize numerous NFs and to evaluate the adequacy of use in biomedical fields.

A novel amylolytic enzyme producing thermoalkaliphilic bacterium, the source of industrially used enzymes was isolated. Isolated strain was identified by morphological, physio-biochemical tests and the 16S rRNA gene sequence analysis. The optimal conditions of enzyme activity were determined. For higher α-amylase production, the variables such as yeast extract, starch, CaCl2, (NH4)2SO4, NaCl and MgSO4 in the α-amylase production medium, the temperature and pH were screened by Plackett–Burman design and optimised using response surface methodology (RSM). The optimal conditions were found to be 0.15 g/L for starch, 0.15 mg/L for CaCl2 and 60 °C for temperature. By using RSM model, amylase production increase was achieved sevenfold. It is showed that this method can be utilised to optimize α-amylase production in athermophilic bacteria such as Bacillus paralicheniformis. Keywords: α-amylase; Bacillus paralicheniformis; optimization; response surface methodology.

WOS: 000452499400011, The aim of this work is to investigate the mechanical properties and microstructures of friction-stir welded (FSWed) St52 structural steel joints. In this study, St52 steel plates with a thickness of 4 mm were butt-welded by friction-stir welding (FSW) using a tungsten carbide tool having a conical pin. The microstructure of the welded zone consists of equiaxed fine ferrite, grain boundary ferrite, Widmanstatten ferrite, and aggregates of ferrite + cementite. The microhardness measurements showed that the hardness of the welded zone was significantly higher than that of the base metal. The FSWed St52 joint exhibited a significant strength overmatching in the weld region and a strength performance similar to or slightly higher than that of the base plate.

We investigated the postsurgical effects of splenectomy with additional curcumin therapy, as an antioxidant, anti-inflammatory substance among the lipid profile and histopathological changes.32 rats were randomly divided into four groups: control group (L): laparotomy, sham group: splenectomy (S), splenectomy group treated with curcumin (SC) and splenectomy group treated with corn oil (SCO) for 28 days. The primary outcomes; total cholesterol (TC), triglycerides (TG), high-density lipoprotein (HDL), low-density lipoprotein (LDL), oxidized LDL (ox-LDL) very-low-density lipoprotein (VLDL) and lectin-type oxidized LDL receptor 1 (LOX-1), secondary outcomes: nuclear factor kappa B (NF-кB), malondialdehyde (MDA), glutathione peroxidase (GPx), superoxide dismutase (SOD) were measured. Histopathological changes were examined in vascular, intestinal and lung tissues. The analysis was performed by ANOVA.TG, LDL, ox-LDL, and LOX-1 elevated in S group while reduced by curcumin compared with L group (p 0.05). Serum and tissue levels of NF-кB and MDA were higher in S group and lower in SC group than L group (p 0.05). Serum and intestinal levels of SOD and GPx increased in L group while reduced by curcumin (p 0.05). Total histopathological scores of intestinal tissues were higher in S and SCO groups compared to L and SC groups (p 0.05). No major changes in vascular and lung tissues were observed except the lymphoid follicles which was higher in S and SCO groups compared to L and SC groups (p 0.05).Curcumin partially improved the lipid profile dysfunction by modulating NF-кB, MDA, SOD, and GPx in splenectomized rats while less likely improving any vascular and alveolar regeneration.

Purpose: To evaluate the inner retinal and choroidal thicknesses in patients with early retinitis pigmentosa. Methods: We analyzed spectral-domain optical coherence tomography images of 35 retinitis pigmentosa patients and 40 healthy individuals. We measured macular and ganglion cell complex thicknesses. We took choroidal thickness measurements in the subfoveal region and 500, 1,000, and 1,500 mm from the foveal center. Results: Patients with retinitis pigmentosa had significantly thinner macular thicknesses and choroidal thicknesses in all measurements, and their individual ganglion cell complex thickness measurements were lower than those in healthy individuals. The mean ganglion cell complex thickness was significantly lower in patients with retinitis pigmentosa than that in controls. The mean macular thickness was significantly correlated with the mean choroidal and mean ganglion cell complex thicknesses. (We found no correlation between the mean choroidal thickness and the mean ganglion cell complex thickness). Conclusions: The choroid was mildly affected in our patients with early retinitis pigmentosa. The tendency toward significance in the inner retina was possibly caused by a good visual acuity.

The present study deals with the improvement of the mechanical and dielectric properties of low-density polyethylene (LDPE) by incorporating BiSr2CaCu2O6.5(coded as Bi-1212) ceramic powder. In this context, LDPE/Bi-1212 films with different ceramic weight contents were prepared by hot press technique. The ceramic reinforcing material was produced by a solid-state reaction technique. While the surface morphologies of the films were determined using a scanning electron microscope (SEM), the chemical structure analyses of the samples were performed by Fourier transform infrared (FTIR) spectroscopy. The mechanical performances of the specimens were evaluated by determining the tensile strength, Young’s modulus, percentage strain at break, and energy at the break values obtained by stress-strain curves. The real and imaginary components of the complex permittivity, as well as the alternating current (ac) conductivities of the samples, were measured within in the frequency interval of 1 Hz-1 MHz between 293 K and 353 K. As a result of tensile properties analyses as well as the investigations of ac electrical parameters, it was revealed that the LDPE/1.0 wt.-% Bi-1212 composite has a promising potential in electronic applications due to its improved mechanical durability, charge storage ability and conductivity.

The aim of this study was to investigate the oxidative and apoptotic potential of fluoxetine, a widely used antidepressant in Turkey and the world, and of its metabolite norfluoxetine on a model non-target organism, Daphnia magna to see how exposure to this group of antidepressants (specific serotonin reuptake inhibitors) could affect the aquatic environment in which they end up. Juvenile D. magna specimens were chronically exposed to fluoxetine and norfluoxetine alone and in combination at concentrations found in the aquatic environment (0.091 and 0.011 μg/L, respectively) and to their 10-fold environmental concentrations for 21 days. Another group of 17-day-old animals were subacutely exposed to 100-fold environmental concentrations for four days. After exposure, we measured their glutathione peroxidase (GPx) and cholinesterase (ChE) activities, thiobarbituric acid-reactive substances (TBARS), and total protein content spectrophotometrically, while mitochondrial membrane potential (MMP) was analysed by fluorescence staining, and cytochrome c and ERK1/2 protein content by Western blotting. This is the first-time cytochrome c and ERK1/2 were determined at the protein level in D. magna. We also measured their carapace length, width, and caudal spine length microscopically. At environmental concentrations fluoxetine and norfluoxetine caused an increase in ChE activity and brood production. They also caused a decrease in juvenile carapace length, width, and caudal spine length and depolarised the mitochondrial membrane. At 10-fold environmental concentrations, GPx activity, lipid peroxidation levels, cytochrome c, and ERK1/2 protein levels rose. The most pronounced effect was observed in D. magna exposed to norfluoxetine. Norfluoxetine also decreased brood production. Similar effects were observed with subacute exposure to 100-fold environmental concentrations. However, total protein content decreased. All this confirms that fluoxetine and norfluoxetine have oxidative and apoptotic potential in D. magna. Daphnia spp. have a great potential to give us precious insight into the mechanisms of environmental toxicants, but there is still a long way to go before they are clarified in these organisms.

To evaluate the choroidal and retinal layers with optical coherence tomography (OCT) and retinal microvascular structures with optical coherence tomography angiography (OCTA) in systemic lupus erythematosus (SLE) patients. In this prospective, cross-sectional and comparative study, a total of 35 SLE patients and 35 healthy control participants were included. SLE patients who were using hydroxychloroquine (HCQ) and/or immunosuppressive agents are evaluated with OCT and OCTA. SLE patients who have no HCQ maculopathy observed in OCT were included in the patient group. Mean macular thickness and ganglion cell inner plexiform layer (GC-IPL) thicknesses were thinner in the patient group. When the parameters obtained with OCTA were evaluated, vessel (VD) and perfusion density (PD) were significantly lower in the patient group. Central foveal thickness and foveal avascular zone parameters were negatively correlated. In addition, VD and PD, and GC-IPL thicknesses were positively correlated. Application of OCTA for the evaluation of microvasculature in SLE patients may be useful in subclinical changes.

Objective: Bipolar disorder and unipolar depressive disorder are complex phenotypes. There appear to be phenotypical, mechanistic, and therapeutic differences between bipolar depression (BD) and unipolar depression (UD). There is a need for understanding the underlying biological variation between these clinical entities. The role of oxidative processes underlying bipolar disorder and depression has been demonstrated. Thiol-disulfide homeostasis (TDH) is a recent oxidative stress marker. In this study, we aimed to inspect patients with bipolar depression and unipolar depression in terms of thiol-disulfide balance and to compare them with healthy controls.Methods: Patients admitted to the outpatient clinic of Ankara Numune Training and Research Hospital and diagnosed either as a depressive episode with bipolar disorder (n = 37) or unipolar depression (n = 24) according to DSM-5 criteria, along with healthy controls (HC) (n = 50), were included in the study. Native thiol, total thiol, and disulfide levels were compared across the groups.Results: In comparison to HC, both BD and UD groups had higher disulfide levels, disulfide/native thiol ratio, and disulfide/total thiol ratio. No significant differences between BD and UD were detected in terms of disulfide level, disulfide/native thiol ratio, and disulfide/total thiol ratio.Conclusion: Increased levels of disulfide, native thiol, and disulfide/total thiol ratios compared to healthy controls in both UD and BD groups may be indicative of the presence of oxidative damage in these two clinical conditions. To clarify the role of oxidative stress in the pathophysiology of depressive disorders and investigate TDH, longitudinal studies in patients with medication-free UD and BD are required.

Objectives Hepatic fibrosis is a complex and dynamic process, such as “wound healing”. The effect of 3-deazaneplanocin A (DZNep) via enhancer of zeste homolog 2 (EZH2) inhibition on transforming growth factor, matrix metalloproteinases 2-9 (MMP2, MMP9) and matrix metalloproteinases inhibitor 3 (TIMP3), alpha-smooth muscle actin (α-SMA), collagen 1A1(COL1A1), and collagen 3A1 (COL3A1) genes/proteins in human hepatic stellate cell line were examined. Inhibition effect of EZH2 on colony formation and migration were investigated. Methods 5 μM DZNep was treated to LX2 cells for 3 days. Real time PCR and Western blot method were used for analyses. Results DZNep was shown to reduce colony formation and migration. It increased the α-SMA only in gene expression level but decreased at the protein levels. It down-regulated both gene expression and protein levels of EZH2, while up-regulated gene expression and protein levels of TGF-β. DZNep induced gene expression and protein levels of MMP2 and TIMP3. However, DZNep induced COL1A1 and COL3A1 gene expression levels but reduced protein levels only in COL3A1 but not COL1A1. Conclusion DZNep has a positive anti-fibrotic effect by reducing α-SMA and COL3A1 protein levels in the LX2 cell line, however, we have found that DZNep may also has fibrotic effect because it increases TGF-β both expression and protein levels.

The increase in the occurrence of the pharmaceuticals in the environmental compartments is becoming emerging concern as it reflects their inefficient treatment in the wastewater treatment plants which are the main sources of these micropollutants. Non-steroidal anti-inflammatory drugs (NSAIDs) are one of the most commonly prescribed and frequently detected pain medications in wastewater treatment plants. A lab scale sequencing batch reactor (SBR) was operated for seven months and acute inhibitory effect of NSAIDs on activated sludge was tested with respirometry. Culture amendment with different concentrations of NSAIDs in the presence as well as absence of nitrification inhibitor resulted in considerable variation in the oxygen uptake rate (OUR) profiles. The decrease in OUR and nitrate production rate governed with reduced heterotrophic and nitrification activity. The kinetics of half saturation for growth and maximum autotrophic growth rates are determined to be affected negatively by the acute impact of anti-inflammatory pharmaceuticals even at the environmentally relevant concentrations. High removal of tested NSAIDs was observed even for the first time introduce with these compounds.

The aim of this study is to evaluate the retinal and choroidal structures in r- and nr-axSpA patients using spectral domain optical coherence tomography (SD-OCT) and to compare changes with healthy controls. In this cross-sectional study, 70 axSpA patients (50 radiographic- and 20 nr-axSpA) and 50 healthy control subjects were included. Choroidal thickness (ChT), macular thickness, retinal nerve fiber layer (RNFL), and the ganglion cell complex (GCC) were measured by SD-OCT. For ChT values, seven lines at nasal and temporal were drawn at 500-μm intervals, centering the subfoveal sclerochoroidal junction. Analysis of the data was performed with the SPSS program. Mann–Whitney U test was performed for comparison of non-normally distributed continuous data; Student’s t test was used for normal distributed data. No significant difference was observed between 70 (66% male; mean age 39.7 ± 10.4 years) axSpA patients (50 radiographic and 20 nr-axSpA) and 50 (mean age 41.2 ± 6.2 years) healthy control subjects (p 0.417). R-axSpA and nr-axSpA groups and control group were similar in terms of spherical equivalent, intraocular pressure, axial length, and body mass index (p 0.574, p 0.874, p 0.918, p 0.344, respectively). While mean macular and GCC thicknesses were significantly lower in the patient group than in the healthy group, there was no significant difference between the two groups in terms of RNFL thickness. The present study showed that there was no significant relationship between markers and scores indicating disease activity and ChT, MT, RNFL, and GCC thicknesses. However, an increase in choroidal thickness and involvement of the retinal layers has also been demonstrated in patients with spondyloarthritis. In addition, the relationship between disease activity and retinal layer involvement is remarkable in the r-axSpA group.

Lipases are one of the most important catalysts for several industries such as detergent, dairy, and textile industry due to their bio-catalytic ability in aqueous and non-aqueous media. Stability to extreme conditions is an important property since it makes enzymes suitable to several industrial processes. In this study, lipase producing soil bacteria were screened and identified with 16S rDNA sequencing. A new hyper-thermophilic lipase named as Bacillus subtilis LP2 isolate was partially purified by ammonium sulphate precipitation with 17.8-fold purification and 583 U/mg specific activity. Maximum activity was exhibited at pH 7 and 80 °C with the substrate tween 80 KM and Vmax values were calculated as 18.3 mM and 680 U/mg with a catalytic efficiency (kcat/KM) of 307 s−1M−1. These results indicate that lipase from Bacillus subtilis LP2 can be a valuable candidate for industrial applications such as organic synthesis and fats and oils industry due to their efficient catalysis in higher temperatures.

Theophylline is widely used as a bronchodilator drug in asthma and chronic obstructive lung disease because it is effective and inexpensive. Theophylline blood concentrations should be monitored since its therapeutic index is narrow, its optimum blood levels range from 10 to 20 μg/mL; its serious side effects take place over 20 μg/mL; its efficacy falls below 10 μg/mL blood concentrations. The aim of the present study is to formulate and characterize oil-in-water microemulsion systems for oral delivery of theophylline. Microemulsion formulations represent an interesting delivery vehicle for poorly water-soluble drugs, allowing for improving their solubility and dissolution properties. A simple and reliable UV-Spectrophotometric method was developed and validated for the determination of theophylline in the concentration range of 25- 150 μg/mL. In vitro drug release profile showed that after 1 hour, 40% of the drug released through the formulation in Simulated Intestinal Fluid at pH 6.8 as a release medium and the microemulsion formulations released more than 75% of the drug during the 5 hours study period. The globule size of drug-loaded formulations was in the range of 203.6 ± 0.2 nm. Results confirmed that the proposed microemulsion formulation containing theophylline could improve and control the drug release profile in comparison to the conventional dosage form.

The present study evaluated the bond strengths of prefabricated PolyEtherKetoneKetone (PEKK) posts, PEKK posts custom-configured according to root-canal size, and conventional fiber posts. A total of 30 maxillary incisors were randomly divided into three groups, as follows: Group 1: fiber posts; Group 2: prefabricated PEKK posts; Group 3; custom-made PEKK posts. Following endodontic treatment, post spaces were prepared, and posts were cemented with resin cement. Push-out bond strength testing was performed using a universal testing machine, and fractures modes were examined under a scanning electron microscope. Data were analyzed using One-way ANOVA and Tukey's HSD tests, with the level of significance set at .05. The highest bond-strength values in the cervical section were observed with the custom-made PEKK post (17.3470 MPa), whereas the highest bond-strength values in the middle and apical sections were observed with the conventional fiber posts (11.5375 MPa and 6.8625 MPa, respectively). Bond-strength values for all posts systems decreased in a cervical to apical direction. PEKK posts are a suitable alternative to fiber posts. Although custom-made PEKK posts demonstrated better bond strength than prefabricated PEKK posts, further studies are needed to evaluate their clinical performance.