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Mo-Ni-B-Al as-cast alloys containing 35.5-58.7 wt% Mo, 23.0-57.6 wt% Ni, 3.3-5.2 wt% B, and 2.2-13.5 wt% Al were synthesized by Self-Propagating High-Temperature Synthesis (SHS) using a mixture of MoO3, NiO, B2O3 and Al powders in order to obtain low-cost Mo2 NiB2 containing hard materials. The first series of experiments were performed using 1.05 times the stoichiometric amount of Al. In the second series of experiments, FactSage thermochemical modeling software was used to minimize Al increasing the Mo2NiB2 formation in the as-cast alloys. The products were characterized by using atomic absorption spectrometry (AAS), X-ray diffraction (XRD), scanning electron microscopy (SEM) and micro-hardness techniques.

In this study, Al-Co-Ni ternary alloys were synthesized, in order to obtain low-cost starting material for Ni-based superalloy production, by a self-propagating high temperature synthesis (SHS) both under normal gravity conditions (a = 9.81 m/s2) and under high gravity conditions (up to 1000 g-force) by using a centrifugal machine. The mixture of Co3O4-NiO powder were reduced by Al powder for the production of SHS alloys with the estimated compositions of 5–10 mass% Al, 20–65 mass% Co, 25–75 mass% Ni. The effect of green mixture compositions and centrifugal overload on combustion temperature, alloy/slag separations, chemical composition and microstructure of final alloys were investigated. The chemical analysis results showed that production of SHS alloys were achieved by having up to 86.12% of Co and 92.32% of Ni recoveries. The highest metal recovery value was obtained in SHS alloy with the estimated composition of 10%Al-65%Co-25%Ni by the addition of 20% Al2O3 into the green mixture. The metal/slag separation efficiency increased by increasing the centrifugal overload.

Denisa Ficai,1 Maria Sonmez,1,2 Madalina Georgiana Albu,2 Dan Eduard Mihaiescu,1 Anton Ficai,1 Coralia Bleotu3 1Faculty of Applied Chemistry and Material Science, Politehnica University of Bucharest, 2Leather and Footwear Research Institute, National Research and Development Institute for Textiles and Leather, 3Stefan S Nicolau Institute of Virology, Romanian Academy, Bucharest, Romania Abstract: A layer-by layer technique was successfully used to obtain collagen/hydroxyapatite-magnetite-cisplatin (COLL/HAn-Fe3O4-CisPt, n=1–7) composite materials with a variable content of hydroxyapatite intended for use in the treatment of bone cancer. The main advantages of this system are the possibility of controlling the rate of delivery of cytostatic agents, the presence of collagen and hydroxyapatite to ensure more rapid healing of the injured bone tissue, and the potential for magnetite to be a passive antitumoral component that can be activated when an appropriate external electromagnetic field is applied. In vitro cytotoxicity assays performed on the COLL/HAn-Fe3O4-CisPt materials obtained using a layer-by layer method confirmed their antitumoral activity. Samples with a higher content of hydroxyapatite had more antitumoral activity because of their better absorption of cisplatin and consequently a higher amount of cisplatin being present in the matrices. Keywords: multifunctional materials, antitumoral activity, scaffold, bone grafts

Abdullah Kaya,1 Yakup Aksoy,2 Yıldıray Yildirim,3 Murat Sonmez3 1Department of Ophthalmology, Anittepe Military Dispensary, Ankara, Turkey; 2Department of Ophthalmology, Girne Military Hospital, Girne, Cyprus; 3Department of Ophthalmology, GATA Haydarpasa Training Hospital, Istanbul, TurkeyWe read with great interest the article titled “Value of optical coherence tomography in the detection of macular pathology before the removal of silicone oil” by Rashad et al.1 The authors have evaluated the optical coherence tomography (OCT) findings before the removal of silicone oil (SiO). We congratulate the authors for this well-organized study and would like to contribute to their findings.View original paper by Rashad and colleagues.

Catarina Marques,1 José MF Ferreira,1 Ecaterina Andronescu,2 Denisa Ficai,2 Maria Sonmez,3 Anton Ficai21Department of Materials and Ceramics Engineering, Centre for Research in Ceramics and Composite Materials, University of Aveiro, Aveiro, Portugal; 2Faculty of Applied Chemistry and Material Science, University Politehnica of Bucharest, Bucharest, Romania; 3National Research and Development Institute for Textiles and Leather, Bucharest, RomaniaAbstract: The purpose of this review is to present the most recent findings in bone tissue engineering. Special attention is given to multifunctional materials based on collagen and collagen–hydroxyapatite composites used for skin and bone cancer treatments. The multifunctionality of these materials was obtained by adding to the base regenerative grafts proper components, such as ferrites (magnetite being the most important representative), cytostatics (cisplatin, carboplatin, vincristine, methotrexate, paclitaxel, doxorubicin), silver nanoparticles, antibiotics (anthracyclines, geldanamycin), and/or analgesics (ibuprofen, fentanyl). The suitability of complex systems for the intended applications was systematically analyzed. The developmental possibilities of multifunctional materials with regenerative and curative roles (antitumoral as well as pain management) in the field of skin and bone cancer treatment are discussed. It is worth mentioning that better materials are likely to be developed by combining conventional and unconventional experimental strategies.Keywords: bone graft, cancer, collagen, magnetite, cytostatics, silver

OBJECTIVE: Relapsed/refractory AML cases are much more resistant to chemotherapy. Venetoclax is a highly sensitive BCL-2 inhibitor. It was aimed to evaluate the effects of venetoclax therapy on real-world R/R AML survival outcomes, the effects of the cytogenetic characteristics of the patients and previous clinical applications on treatment response, and venetoclax treatment toxicity. PATIENTS AND METHODS: The study included patients who only received a venetoclax-based salvage on R/R AML patients from Turkey. The study included a total of 62 patients from 6 different centers in Turkey. Response to 2 cycles of venetoclax treatment was assessed by bone marrow blast rate. The demographic data, cytogenetic characteristics, AML type, MDS type, response rates and overall survival of the patients after venetoclax combination treatment were assessed. Median age of the patients was 65 (19-85). Mean number of prior treatments was 2.67 ±1.75. RESULTS: 13 patients (21%) had a history of allogenic stem cell transplantation. 58 (93.5%) had received HMA therapy before venetoclax. 36 patients (58.1%) had de-novo AML, and 25 (40.3%) previously had MDS. Treatment response was evaluated as complete remission (n = 21, 33.9%), partial response (n = 17, 27.4%), and treatment failure (n = 24, 38.7%). Patients in the TF group were significantly more likely to have poor cytogenetic and to have received allogeneic transplants. The mean estimated overall survival after the venetoclax treatment was 9.13 ± 0.75 months. CONCLUSIONS: The study population consisted of a group of patients who had relapsed or primary refractory disease with poor prognosis, despite numerous rounds of chemotherapy. It is our belief that the high response rates obtained with the combination of venetoclax/HMA, and having obtained positive results with poor risk patients, indicated a promising perspective for R/R AML patients. [ABSTRACT FROM AUTHOR]

In the present work, V2O5 thin films were fabricated with both commercial and solution combustion synthesised V2O5 resorting to a single spin coating sol–gel deposition. Structural and morphological properties of V2O5 powder were investigated first, subsequently followed by a detailed investigation of the optical and electrochemical properties of thin films. The film, which was coated from as-synthetised powder onto corning substrate had a transparency of greater than 85% in the visible region for sol–gels exhibited absorption edges at ∼380 nm. The optical band-gap energy was evaluated to be 2.7 eV, while the coloration efficiency of this film was found to be 36.8 cm2 C−1. The film thickness range of 100–300 nm was demonstrated in 1-layer. The main properties of the afore discussed thin films provide further encouragement for application in future nanoscale (opto-) electronic devices as they are reproducible, cost-effective, and quick to fabricate. [ABSTRACT FROM AUTHOR]

The photogrammetry enables to getting high accuracy measurement with low-cost and easy application in documentation of historical structures. The object details are signified with lines in cultural heritage documentation by photogrammetry. The combination of all the lines create 3D wireframe model of the measurement object. In addition, patch surfaces of the wireframe are mapped with the texture from the images for more realistic visualization. On the other hand, the progress on computer vision and image processing techniques is allowing automatically perform the photogrammetric process. A large number of points that are called dense point cloud can be measured from coverage area of multi view images. The dense point cloud represents the object shape with small space measured points while the wireframe photogrammetry is representing the object with lines. In this study these two photogrammetric methods were evaluated with respect to visualization, cost, labour and measurement time through 3D modelling of historical structures of Sultan Selim Mosque and Yusuf Aga Library. [ABSTRACT FROM AUTHOR]

Mehmet Salih Boga,1 Mehmet Giray Sönmez2 1Department of Urology, Antalya Training and Research Hospital, Antalya, Turkey; 2Department of Urology, Meram Medical Faculty, Necmettin Erbakan University, Konya, Turkey Abstract: Partial nephrectomy (PN), also known as nephron sparing surgery, is considered as the first-line treatment in small renal masses, especially in T1/2 tumors, and is applied as a standard treatment in advanced centers. The main expected outcomes from an ideal PN are surgical margin negativity, minimal impairment in renal function, and any surgical complications. Many authors have defined PN techniques as “zero ischemia partial nephrectomy”, where surgery is performed without clamping the main renal artery in order to protect the renal parenchyma from ischemic injury. Various PN techniques employed by surgeons include: selective or segmental renal artery clamping technique; off-clamp, clampless, or unclamped technique; preoperative superselective transarterial tumor embolization technique; sequential/ modified sequential preplaced suture renorrhaphy technique, radio frequency ablation-assisted technique, and combination of these techniques. The common goal of all these techniques is to provide zero ischemia without hilar clamping. This systematic review focuses on the long-term functional outcomes of PNs performed by zero ischemia techniques. Keywords: zero ischemia, partial nephrectomy, renal function, complication, nephron sparing surgery, renal tumor

It has been claimed that artificial insemination (AI) of cows with frozen-thawed semen treated with commercially produced kits, Heiferplus ™ (HP, in favour of female gender) and Bullplus ™ (BP, in favour of male gender), increases the birth chance of calves with desired sex ratio by at least 20-25% and pregnancy rates by at least 5-20%. Hence, this study was conducted to investigate the efficacy of HP and BP kits as combined with AI on the pregnancy rates, foetal sex ratios and some reproductive parameters in cows. For this, a total of 200 cows (100 Holsteins and 100 Simmentals) from three to five years old were used. Fifty Holstein and 50 Simmental cows served as controls. The other half of Holstein and Simmental cows was artificially inseminated with frozen-thawed semen treated with HP and BP, respectively. Findings showed that the AI of cows with frozen-thawed semen treated with HP had no significant effect on the pregnancy rate [52.0% (26/50) in HP group; 56.0% (28/50) in control group], female calf ratio [52.0% (13/25) in HP group; 44.4% (12/27) in control group], embryonic death, abortion, stillbirth, twinning and gestation length as compared to the control group. Similarly, AI of cows with frozen-thawed semen treated with BP did not lead to any significant effect on the pregnancy rate [64.0% (32/50) in BP group; 58.0% (29/50) in control group], male calf ratio [53.1% (17/32) in BP group; 39.3% (11/28) in control group] and other reproductive parameters as compared to the control group. In conclusion, HP and BP treatments of semen used in the AI provided only slight, non-significant increases in female (7.6%) and male (13.8%) calf ratios, respectively. [ABSTRACT FROM AUTHOR]

Purpose: To provide a rapid method to reduce the radiofrequency (RF) E-field coupling and consequent heating in long conductors in an interventional MRI (iMRI) setup. Methods: A driving function for device heating (W) was defined as the integration of the E-field along the direction of the wire and calculated through a quasistatic approximation. Based on this function, the phases of four independently controlled transmit channels were dynamically changed in a 1.5 T MRI scanner. During the different excitation configurations, the RF induced heating in a nitinol wire immersed in a saline phantom was measured by fiber-optic temperature sensing. Additionally, a minimization of W as a function of phase and amplitude values of the different channels and constrained by the homogeneity of the RF excitation field (B1) over a region of interest was proposed and its results tested on the benchtop. To analyze the validity of the proposed method, using a model of the array and phantom setup tested in the scanner, RF fields and SAR maps were calculated through finite-difference time-domain (FDTD) simulations. In addition to phantom experiments, RF induced heating of an active guidewire inserted in a swine was also evaluated. Results: In the phantom experiment, heating at the tip of the device was reduced by 92% when replacing the body coil by an optimized parallel transmit excitation with same nominal flip angle. In the benchtop, up to 90% heating reduction was measured when implementing the constrained minimization algorithm with the additional degree of freedom given by independent amplitude control. The computation of the optimum phase and amplitude values was executed in just 12 s using a standard CPU. The results of the FDTD simulations showed similar trend of the local SAR at the tip of the wire and measured temperature as well as to a quadratic function of W, confirming the validity of the quasistatic approach for the presented problem at 64 MHz. Imaging and heating reduction of the guidewire were successfully performed in vivo with the proposed hardware and phase control. Conclusions: Phantom and in vivo data demonstrated that additional degrees of freedom in a parallel transmission system can be used to control RF induced heating in long conductors. A novel constrained optimization approach to reduce device heating was also presented that can be run in just few seconds and therefore could be added to an iMRI protocol to improve RF safety. [ABSTRACT FROM AUTHOR]

This study was carried out to investigate smoke-induced structural and biochemical changes and protective effects of co-administered melatonin and vitamin C in the kidney. Twenty-four Wistar adult female rats were used in this study. Animals were divided into four groups. The first group rats were used as control. The second group of rats inhaled cigarette smoke. Smile smoke inhaling third and fourth group rats received melatonin and vitamin C, respectively. At the end of experimental study, kidney tissues and blood samples were taken under ether anesthesia. Tissues were prepared and examined by light microscopy. Malondialdehyde and glutathione levels and catalase activity were determined. By light microscopic observation, a decrease of Bowman space of some renal corpuscles, foamy-like tubules, dilatation and congestion of the peritubuler vessels, and atrophy of the some renal corpuscles were observed in group II. In groups III and IV melatonin and vitamin C relatively protected the kidney tissue against smoke intoxication. Biochemical examination showed that malondialdehyde and glutathione levels and catalase activity in group II were higher than in group I. Melatonin and vitamin C injection to group Ill and IV caused a decrease in malondialdehyde and glutathione levels. Catalase activity did not change in these groups. We have shown that cigarette smoke inhalation caused structural changes in the kidney. However, melatonin and vitamin C administration produced in some degree protection against smoke-induced damage. [ABSTRACT FROM AUTHOR]

Recently, cost-efficient nitrate reducing biogranules were suggested as an alternative to axenic microbial cultures for development of microbial self-healing concrete. In a marine environment, biogranule containing microbial self-healing concrete showed simultaneous self-healing of cracks and immunisation against rebar corrosion. Yet, information about the production strategy of these biogranules and their compatibility with a mortar matrix is limited. This study presents the production of biogranules and their compatibility with mortar specimens when incorporated at dosages between 0.36% to 4.30% w/w cement (0.25% to 3% of bacteria w/w cement). In-house produced biogranules composed of 70% bacteria and 30% of minerals w/w of biogranule were used for the compatibility tests. In test mortars, calcium formate (CF) and calcium nitrate (CN) were used as regular nutrient admixtures, and nutrient content was set identical in every batch. Up to 2.9% incorporation, biogranules had no significant influence on the fresh properties of mortar. More than 2.9% incorporation caused poor workability and a 26% decrease in 3-Day compressive strength of biomortar specimens. Overall, the biogranules produced are compatible with a cementitious matrix up to 2.9% w/w cement, and even up to 3.6% if early age strength is not essential, which makes biogranules one of the most compatible microbial healing agents among the suggested agents in the literature.

• V 2 O 5 powder was prepared by SCS using different type of fuels and mix fuel. • Effect of fuel-oxidizer ratio on the structure of V 2 O 5 particles was investigated. • The finest V 2 O 5 particles was synthesised by using mix fuel having T ad of 978 K with the release of 20.5 mol gas products. • Average particle size of V 2 O 5 powders were measured as 158 nm. The present study shows the effects of the process parameters on the combustion synthesised' powder properties using a systematic design of experiments. It describes the fabrication of high purity V 2 O 5 powders with the manipulation of fuel types and fuel-to-oxidizer ratios. Additionally, for the first time the mixture of fuels was used to demonstrate clearly the role of the fuel on the powder properties. Flame temperature of the reaction was calculated for each parameter to understand how the reaction kinetics affect the powder properties especially primary particle size and morphology. Correlation between the physical and chemical properties of the powders and the precursor's condition was successfully built. [ABSTRACT FROM AUTHOR]

Anew series of two types of acyclic binuclear Schiff base complexes, prepared by the template condensation of N-aminopyrimidine and 2,3-butandion in the presence of Cu(II), Ni(II), Co(II) and Zn(II) in n-BuOH solution, were analyzed and characterized by elemental analyses, IR and electronic spectroscopy, conductivity and magnetic measurements. From the conductivity measurements, it is concluded that the complex of NiII is a 1:1 type of electrolyte. All the complexes have sub-normal magnetic moments in accordance with their binuclear nature. The thermal behaviour of the complexes was studied by thermogravimetry.

Aim: We aimed to investigate the effects of immunohistochemical and molecular presence of double-hit lymphomas (DHL) (combined expression of myc and bcl-2) on overall and progression-free survival rates of patients with extranodal diffuse large B-cell lymphoma (DLBCL). Methods: A total of 31 patients (17 female, 14 male; mean age 57 years) with diagnosis of extranodal DLBCL were included into the study. Patients transforming from low grade B cell lymphoma, and patients with HIV positivity were not included. In a retrospective manner, patient characteristics were noted (age at diagnosis, sex, sites of extranodal involvement, stage, high-risk group, histopathological diagnosis, IPI score, LDH level at diagnosis, bone marrow involvement, and treatment modalities). Histopathological specimens underwent immunohistochemical (bcl-6, bcl-2, myc, CD10, Mum-1) and molecular (bcl-2 and myc, by means of PCR) analysis. All patients was treatment with R -CHOP protocol. Results: DHL was observed immunohistochemically in only one patient, while molecular studies found 6 cases. Three-month overall survival rates were 50% and 88% in DHL positive and negative groups, respectively. Six-month overall survival rates were 16% and 76% in DHL positive and negative groups, respectively. Progression-free 3-month survival rates were 51% and 88% in DHL positive and negative groups, respectively. Progression-free 6-month survival rates were 33% and 76% in DHL positive and negative groups, respectively. No relation with histopathological type of the disease was noted. Conclusion: We conclude that DHL presence in patients with extranodal DLBCL was an independent factor leading to shortened overall or progression-free survival. [ABSTRACT FROM AUTHOR]

Abstract Background The field of interventional cardiovascular MRI is hampered by the unavailability of active guidewires that are both safe and conspicuous. Heating of conductive guidewires is difficult to predict in vivo and disruptive to measure using external probes. We describe a clinical-grade 0.035” (0.89 mm) guidewire for MRI right and left heart catheterization at 1.5 T that has an internal probe to monitor temperature in real-time, and that has both tip and shaft visibility as well as suitable flexibility. Methods The design has an internal fiberoptic temperature probe, as well as a distal solenoid to enhance tip visibility on a loopless antenna. We tested different tip-solenoid configurations to balance heating and signal profiles. We tested mechanical performance in vitro and in vivo in comparison with a popular clinical nitinol guidewire. Results The solenoid displaced the point of maximal heating (“hot spot”) from the tip to a more proximal location where it can be measured without impairing guidewire flexion. Probe pullback allowed creation of lengthwise guidewire temperature maps that allowed rapid evaluation of design prototypes. Distal-only solenoid attachment offered the best compromise between tip visibility and heating among design candidates. When fixed at the hot spot, the internal probe consistently reflected the maximum temperature compared external probes. Real-time temperature monitoring was performed during porcine left heart catheterization. Heating was negligible using normal operating parameters (flip angle, 45°; SAR, 1.01 W/kg); the temperature increased by 4.2°C only during high RF power mode (flip angle, 90°; SAR, 3.96 W/kg) and only when the guidewire was isolated from blood cooling effects by an introducer sheath. The tip flexibility and in vivo performance of the final guidewire design were similar to a popular commercial guidewire. Conclusions We integrated a fiberoptic temperature probe inside a 0.035” MRI guidewire. Real-time monitoring helps detect deleterious heating during use, without impairing mechanical guidewire operation, and without impairing MRI visibility. We therefore need not rely on prediction to ensure safe clinical operation. Future implementations may modulate specific absorption rate (SAR) based on temperature feedback.

Abstract Background Multiple Myeloma (MM) is a B cell neoplasm characterized by the clonal proliferation of plasma cells. Skeletal complications are found in up to 80% of myeloma patients at presentation and are major cause of morbidity. Methods 49 patients were enrolled with MM admitted to Black Sea Technical University Hospital between 2002–2005. Pathologic fractures (PFs) were determined and the patients with or without PF were followed up minumum 3 years for survival analysis. Results PF was observed in 24 patients (49%) and not observed in 25 patients (51%). The risk of death was increased in the patients with PF compared with patients who had no fractures. While overall survival was 17.6 months in the patients with PFs, it was 57.3 months in the patients with no PFs. Conclusion These findings suggest that PFs may induce reduced survival and increased mortality in the MM patients, however, larger sample size is essential to draw clearer conclusions added to these data.

The aim of this study was to detect heavy metal concentrations in the creek which passes through Nigde city garbage dump. In this respect, the soil samples collected in the study area by GPS were analyzed using X-Ray Fluorescence Spectrometer. Traces of heavy metals were observed by using statistical programs on analysis results. Geological observations were taken into consideration. According to the heavy metal concentrations in the Creek, the maximum values were as follows; (mg/ kg) Ti: 4960, V: 520, Cr: 120, Mn: 810, Ni: 460, Cu: 410, Zn: 100 and Pb: 480. The concentration levels of heavy metals in soil caused by garbage dump are listed in the following order; Pb > Cu > V > Ti > Cr > Ni > Zn. high positive correlation were observed between Ti-Mn, V-Ni and Cr-Ni. Medium positive correlations were observed between V-Cr, V-Cu and Ni-Zn. It has been found by chemical analysis data collected from stations established throughout the creek that there is an effect of morphological structure and no geological anomaly has been formed. According to chemical analysis results, statistical programs give important accuracy. heavy metals, which give anomaly, differ throughout the creek. The source of these heavy metals was determined as Nigde city garbage dump. For this reason, it was suggested that, in order to refine the study area, a modern, organized storage system must be used instead of wild storage system in storing the urban wastes, and recyclable products must be used in the industry. [ABSTRACT FROM AUTHOR]

Manageable electricity demand capacity and the user activities that make up this demand is crucial for aggregators in residential demand response events. In this study, it was aimed to generate residential electricity power profiles by the enhanced activity-based load models to determine manageable demand potential. A novel method that aggregators may estimate realistic residential manageable demand capacity was presented. The method can also be used to specify which incentives that cause suitable activity changes of the consumer. Studies were performed on several home appliances associated with different activities. Using load models that are based on collected energy consumption data, consumer behaviors, behavioral adaptations, habits, and physical determinants were embedded in both activities and loads' power profiles. It was observed from simulations that deferrable loads had a significant share in total electricity consumption.

Simulated body fluid (SBF) immersion technique is an attractive method for biomaterial synthesis due to the conditions similar to the in vivo synthesis ones. The collagen/hydroxyapatite (COLL/HA) composite biomaterials obtained by immersing the collagen matrices in SBF are usually well mimicking the bone, especially the mineral phase synthesis and properties. Starting from these hypotheses, we have achieved the mineralization of human nasal septum cartilage by SBF immersion technique. For this, nasal septum cartilages were collected from a 33 years old woman and used as obtained. The mineralization was conducted by immersion for 168 hours at ∼37oC and pH=7.4. The cartilage mineralization process by SBF immersion can be compared with the endochondral ossification occurring naturally. When compared with other related materials, the obtained materials have shown better characteristics because the organic phase had been synthesized by the human body and, the mineral phase was deposited by a biomimetic method. Summarizing, the proposed method can be considered an advanced biomimetic method and the obtained materials can be expected to exhibit improved properties. [ABSTRACT FROM AUTHOR]