255 research outputs found
Determinants of Industrial Production in Turkey
The necessity of emphasizing the importance of industrial production for the sustainable growth and development of Turkey has been a topic of discussion in political and academia circles. The growth in industrial production (output) depends on the investment in manufacturing sectors and the demand for the products. Along with internal demand, Turkey tries to support its manufacturing base with export (incentives). Manufacturing items occupy the greatest share of products in export sales. The development of manufacturing capabilities of the country is clearly based on the demand from inside and out. The effect of Turkey’s export on its industrial production throughout 2000’s has been analyzed. For this purpose we developed a VAR model where industrial production index was the dependent variable and export, investment, and interest rate were independent variables. All independent variables were found to be significantly explaining industrial production
Machining strategy development in 5-axis milling operations using process models
Increased productivity and part quality can be achieved by selecting machining strategies and conditions properly. At one extreme very high speed and feed rate with small depth of cut can be used for high productivity whereas deep cuts accompanied with slow speeds and feeds may also provide increased material
removal rates in some cases. In this study, it is shown that process models are useful tools to simulate and compare alternative strategies for machining of a part. 5-axis milling of turbine engine compressors made out of titanium alloys is used as the case study where strategies such as flank milling (deep cuts), point milling (light cuts) and stripe milling (medium depths) are compared in terms of process time by considering chatter stability, surface finish and tool deflections
Terahertz Faraday rotation in a magnetic liquid: High magneto-optical figure of merit and broadband operation in a ferrofluid
We report on the demonstration of a high figure of merit (FOM) Faraday rotation in a liquid in the terahertz (THz) regime. Using a ferrofluid, a high broadband rotation (11 mrad/mm) is experimentally demonstrated in the frequency range of 0.2–0.9 THz at room temperature. Given the low absorption of the liquid, a high magneto-optical figure of merit (5-16 rad.cm/T) is obtained
Terahertz magnetic modulator based on magnetically clustered nanoparticles
Random orientation of liquid-suspended magnetic nanoparticles (Ferrofluids) gives rise to a zero net magnetic orientation. An external magnetic field tends to align these nanoparticles into clusters, leading to a strong linear dichroism on a propagating wave. Using 10 nm-sized Fe3O4, we experimentally realize a polarization-sensitive magnetic modulator operating at terahertz wavelengths. We reached a modulation depth of 66% using a field as low as 35 mT. The proposed concept offers a solution towards fundamental terahertz magnetic modulators
DOES PREOPERATIVE TIBIAL TUBEROSITY – TROCHLEAR GROOVE DISTANCE EFFECT ON POSTOPERATIVE PATELLAR INSTABILITY IN THE PATIENTS WITH KNEE ARTHROPLASTY DUE TO MEDIUM-ADVANCED KNEE OSTEOARTHRITIS?
Objectives: Determining tibial tubercle-trochlear groove distance range as measured before the operation in the patients to whom total knee prosthesis will be applied due to mid to advanced level of osteoarthritic and seeing the post-operative variations in tibial tubercle-trochlear groove distance and evaluating whether it has any impact on the patellofemoral instability that might develop after the operation.46 knees planned to be applied total knee prosthesis due to mid-advanced level of osteoarthritic were examined.
Methods: In the preoperative and postoperative magnetic resonance images MRI routinely taken, tibial tubercle-trochlear groove distance was measured. Later it was examined whether there was correlation between these preoperative and postoperative tibial tubercle-trochlear groove measurements and the data recorded before operation.
Results: Preoperative tibial tubercle-trochlear groove distance was found to be 8.83±3.54, postoperative tibial tubercle-trochlear groovedistance was found to be 8.30±3.89 and preoperative-postoperative tibial tubercle-trochlear groove variation was found to be 0,52±3,64 (p=0,337). In the patients whose alignment was 10 degrees or less, Pre-Op tibial tubercle-trochlear groove distance was measured as 8.74±3.18 and in the patients whose alignment was more than 10 degrees, it was measured as 8.89±3,83 ( p=0.888). In the patients whose alignment was 10 degrees or less, Post-Op tibial tubercle-trochlear groove distance was measured as 8.00±2.85 and in the patients whose alignment was more than 10 degrees, it was measured as 8.52±4.52 (p=0.661). In the patients whose alignment was 10 degrees or less, tibial tubercle-trochlear groove distance variation was measured as 0.74± 3.25 and in the patients whose alignment was more than 10 degrees, it was measured as 0.37± 3.95 (p=0.741).
Conclusion: As a result, although tibial tubercle-trochlear groove distance was observed with a great variation in the osteoarthritic knees at stage 3-4, it was nonetheless measured within normal limits and Post-Op variation was not meaningful. Since this is the first study in the literature on the measurement of tibial tubercle-trochlear groove distance in the total knee prosthesis applications, we hope that it would shed some light on similar studies to be conducted in the future
Skirting terahertz waves in a photo-excited nanoslit structure
Terahertz fields can be dramatically enhanced as they propagate through nanometer-sized slits. The enhancement is mediated by a significant accumulation of the induced surface charges on the surrounding metal. This enhancement is shown here to be dynamically modulated while the nanoslits are gradually shunted using a copropagating optical beam. The terahertz fields are found to skirt the nanoscale photo-excited region underneath the slits, scattering to the far field and rigorously mapping the near field
Stężenia adropiny i albuminy modyfikowanej niedokrwieniem w surowicy w zależności od występowania zespołu policystycznych jajników i wartości BMI
Introduction: The aim of this study was to evaluate the effects of polycystic ovary syndrome (PCOS) and body mass index (BMI) on serum adropin and ischemia modified albumin (IMA) levels.
Materials and methods: This prospective cross-sectional study was performed with a total of 120 women [group1; non-PCOS = 60 (BMI < 25 = 30, BMI ≥25 = 30) and group 2; PCOS = 60 (BMI < 25 = 30, BMI ≥25 = 30)]. Blood samples were collected between the third and fifth days of the women’s menstrual cycles after a night of fasting.
Results: There were no differences between the groups in relation to age, basal follicle stimulating hormone, estradiol, thyroid stimulating hormone, prolactin, high-density lipoprotein cholesterol, total testosterone, dehydroepiandrosterone sulfate levels, systolic and diastolic blood pressures. A significant difference was found in basal luteinizing hormone, fasting glucose, insulin, homeostatic model assessment of insulin resistance, total cholesterol, low-density lipoprotein cholesterol, triglycerides, free testosterone levels, waist-to-hip ratios and the Ferriman-Gallwey scores between the PCOS and non-PCOS patients in the lean and overweight groups (p < 0.05). The serum adropin levels in the lean PCOS group were lower than in the lean non-PCOS group (p < 0.05) and were lower in the overweight PCOS group than in the overweight non-PCOS group (p < 0.05). There was also a statistically significant difference in serum IMA levels in the PCOS group than in the non-PCOS group in both the lean and overweight groups (p < 0.05).
Conclusions: Although serum adropin levels were significantly decreased in the PCOS group, IMA levels increased. Further studies are needed to determine the effects of adropin and IMA in women with PCOS and to use a new marker to monitorize treatment outcomes.
Wstęp: Badanie przeprowadzono w celu oceny wpływu zespołu policystycznych jajników (polycystic ovary syndrome, PCOS) i wskaźnika masy ciała (body mass index, BMI) na surowicze stężenia adropiny i albumin modyfikowanej niedokrwieniem (ischemia modified albumin, IMA).
Materiał i metody: To prospektywne badanie przekrojowe obejmowało 120 kobiet [grupa 1: osoby bez PCOS — n= 60 (BMI < 25 — n= 30; BMI ≥ 25 — n = 30) oraz grupa 2: osoby z PCOS — n= 60 (BMI < 25 — n= 30, BMI ≥ 25 —n = 30)]. Próbki krwi pobierano między trzecim a piątym dniem cyklu menstruacyjnego badanych kobiet, rano na czczo.
Wyniki: Grupy nie różniły się pod względem wieku, podstawowego stężenia hormonu folikulotropowego, stężeń estradiolu, tyreotropiny, prolaktyny, cholesterol frakcji HDL, testosteronu całkowitego i siarczanu dehydroepiandrosteronu ani skurczowego i rozkurczowego ciśnienia tętniczego. Stwierdzono natomiast istotne różnice między grupą z PCOS i bez PCOS w podgrupach osób szczupłych i otyłych w zakresie podstawowego stężenia hormonu luteinizującego, glikemii na czczo, wskaźnika insulinooporności w modelu homeostazy, stężeń cholesterolu całkowitego, cholesterolu frakcji LDL, triglicerydów i wolnego testosteronu, a także wskaźnika talia-biodra oraz oceny w skali Ferrimana-Gallweya (P < 0,05). Stężenia adropiny w osoczu były niższe w grupie szczupłych kobiet z PCOS niż u szczupłych osób niechorujących na PCOS (P < 0,05) oraz były niższe u otyłych osób z PCOS niż u otyłych osób z grupy bez PCOS (P < 0,05). Stwierdzono również statystycznie istotną różnice w stężeniach IMA w surowicy między kobietami z PCOS i bez PCOS, zarówno w podgrupie osób szczupłych, jak i otyłych (P < 0,05).
Wnioski: Mimo że surowicze stężenia adropiny były istotnie niższe w grupie z PCOS, stężenia IMA były podwyższone w tej grupie badanych. Konieczne są dalsze badania w celu określenia wpływu adropiny i IMA u kobiet z PCOS i stosowanie nowych wskaźników do monitorowania efektów leczenia
Breast cancer in association with thyroid disorders
BACKGROUND: The relationship between breast cancer and thyroid diseases is controversial. Discrepant results have been reported in the literature. The incidences of autoimmune and nonautoimmune thyroid diseases were investigated in patients with breast cancer and age-matched control individuals without breast or thyroid disease. METHODS: Clinical and ultrasound evaluation of thyroid gland, determination of serum thyroid hormone and antibody levels, and fine-needle aspiration of thyroid gland were performed in 150 breast cancer patients and 100 control individuals. RESULTS: The mean values for anti-thyroid peroxidase antibodies were significantly higher in breast cancer patients than in control individuals (P = 0.030). The incidences of autoimmune and nonautoimmune thyroid diseases were higher in breast cancer patients than in control individuals (38% versus 17%, P = 0.001; 26% versus 9%, P = 0.001, respectively). CONCLUSION: Our results indicate an increased prevalence of autoimmune and nonautoimmune thyroid diseases in breast cancer patients
Ozone Therapy and Hyperbaric Oxygen Treatment in Lung Injury in Septic Rats
Various therapeutic protocols were used for the management of sepsis including hyperbaric oxygen (HBO) therapy. It has been shown that ozone therapy (OT) reduced inflammation in several entities and exhibits some similarity with HBO in regard to mechanisms of action. We designed a study to evaluate the efficacy of OT in an experimental rat model of sepsis to compare with HBO. Male Wistar rats were divided into sham, sepsis+cefepime, sepsis+cefepime+HBO, and sepsis+cefepime+OT groups. Sepsis was induced by an intraperitoneal injection of Escherichia coli; HBO was administered twice daily; OT was set as intraperitoneal injections once a day. The treatments were continued for 5 days after the induction of sepsis. At the end of experiment, the lung tissues and blood samples were harvested for biochemical and histological analysis. Myeloperoxidase activities and oxidative stress parameters, and serum proinflammatory cytokine levels, IL-1β and TNF-α, were found to be ameliorated by the adjuvant use of HBO and OT in the lung tissue when compared with the antibiotherapy only group. Histologic evaluation of the lung tissue samples confirmed the biochemical outcome. Our data presented that both HBO and OT reduced inflammation and injury in the septic rats' lungs; a greater benefit was obtained for OT. The current study demonstrated that the administration of OT as well as HBO as adjuvant therapy may support antibiotherapy in protecting the lung against septic injury. HBO and OT reduced tissue oxidative stress, regulated the systemic inflammatory response, and abated cellular infiltration to the lung demonstrated by findings of MPO activity and histopathologic examination. These findings indicated that OT tended to be more effective than HBO, in particular regarding serum IL-1β, lung GSH-Px and histologic outcome
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