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Direct aspiration versus follicular flushing in poor responders undergoing intracytoplasmic sperm injection: a randomised controlled trial
No full textObjective To compare follicle flushing three times with direct follicular aspiration in poor responders. Our hypothesis was that follicle flushing three times in poor responders would result in similar oocyte yield compared with direct aspiration in poor responders.
Design A randomised controlled trial performed between January 2015 and June 2015.
Setting University hospital.
Population or sample Eighty eligible poor responders, who were defined as having five or fewer follicles >= 13 mm in average diameter with at least two follicles having maximum diameters >17 mm on the day of human chorionic gonadotrophin administration. Monofollicular cycles, including natural cycles, were excluded from the current trial.
Methods In the double-lumen needle group, oocyte retrieval was performed by flushing three times with 2 ml in each follicle and in the single-lumen group direct follicle aspiration was performed.
Main outcome measure Number of metaphase II oocytes retrieved.
Results The mean number of metaphase II oocytes was similar in both groups (1.9 +/- 0.1 versus 2.1 +/- 0.1, respectively). The clinical pregnancy and live birth rates were similar in both groups (32.5% versus 25% and 25% versus 22.5%, respectively). The only significant difference between the two groups was the duration of oocyte retrieval (178.4 +/- 13.4 versus 236.3 +/- 24.1seconds, respectively, P = 0.01).
Conclusion Follicular flushing is time consuming and has similar results compared with direct follicle aspiration in poor responders
Standardization of adult transthoracic echocardiography reporting in agreement with recent chamber quantification, diastolic function, and heart valve disease recommendations: an expert consensus document of the European Association of Cardiovascular Imaging
No full textAims This European Association Cardiovascular Imaging (EACVI) Expert Consensus document aims at defining the main quantitative information on cardiac structure and function that needs to be included in standard echocardiographic report following recent ASE/EACVI chamber quantification, diastolic function, and heart valve disease recommendations. The document focuses on general reporting and specific pathological conditions such as heart failure, coronary artery and valvular heart disease, cardiomyopathies, and systemic diseases.
Methods and results Demographic data (age, body surface area, blood pressure, and heart rhythm and rate), type (vendor and model) of ultrasound system used and image quality need to be reported. In addition, measurements should be normalized for body size. Reference normal values, derived by ASE/EACVI recommendations, shall always be reported to differentiate normal from pathological conditions. This Expert Consensus document suggests avoiding the surveillance of specific variable using different ultrasound techniques (e.g. in echo labs with high expertise in left ventricular ejection fraction by 3D and not by 2D echocardiography). The report should be also tailored in relation with different cardiac pathologies, quality of images, and needs of the caregivers.
Conclusion The conclusion should be concise reflecting the status of left ventricular structure and function, the presence of left atrial and/or aortic dilation, right ventricular dysfunction, and pulmonary hypertension, leading to an objective communication with the patient health caregiver. Variation over time should be considered carefully, taking always into account the consistency of the parameters used for comparison
Füze üstü telemetre verileri iletim menzilinin sıkıştırma yöntemleri ile arttırılması
No full textTelemetre, kelime anlamı olarak 'uzaktan ölçüm alma' anlamına gelmektedir. Telemetre kavramı, bir sistemin uzaktan kontrol edilmesi ya da izlenmesi amacıyla; sisteme ait çeşitli verilerin anlık olarak elde edilmesini ve bir merkeze iletilerek kaydedilmesini sağlayan uygulamaları kapsar. Telemetre günümüzde; elektrik, su, gaz üretim tesislerinde; haberleşme sistemlerinde; biyomedikal sistemlerde ve bilimsel çalışmalar için dünya üzerinde ve uzayda kurulan sistemlerden ölçüm alınmasında vb. birçok alanda kullanılmakta ve füzeler, uçaklar, tüm hareketli sistemler için; yapılan testlerdeki veri toplama işlemini tanımlamaktadır. Telemetre verileri; füzenin uçuşlu testleri esnasında RF bağlantı ile yer istasyonuna aktarılan sensör verilerini, Küresel Konumlama Sistemi (Global Positioning System, GPS) verilerini ve çeşitli güdüm verilerini içeren veri katarlarıdır.
Telemetre testleri, bir aracın/sistemin kalifikasyonu öncesinde/sonrasında gerçekleştirilen ve tasarım çalışmalarını doğru yönlendirmek amacıyla aracın/sistemin performansıyla ilgili verilerin toplandığı testlerdir. Türkiye’de devlet ve ordunun gereksinimlerine göre farklı türlerde füzeler için tasarım çalışmaları başarıyla sürdürülmekte olup belirli atış alanlarında bu füzelerin telemetre testleri gerçekleştirilmektedir. Bu testlerde elde edilen veriler, tasarım çalışmalarının denetlenmesi ve iyileştirilmesi amacıyla kullanılmaktadır. Telemetre verilerinin tasarım sürecindeki etkisi göz önüne alındığında, testlerin mümkün olduğunca fazla veri toplanarak gerçekleştirilmesi önemlidir. Bu bağlamda telemetre sisteminin, daha çok verinin daha az maliyetle aktarımını sağlayacak biçimde geliştirilmesi bir gereksinimdir. Telemetre verilerinin sıkıştırılarak aktarılması bu gereksinimin karşılanmasında etkili olacaktır. Literatürde yalnızca aktarılan verilerin saklanması sırasında sıkıştırma algoritmalarına başvurulduğu anlaşılmaktadır. Bu durum; yüksek menzile sahip füzelerde, bant genişliği yüksek olan verilerin alınmasına engel teşkil etmekte ve iyileştirilmesi gereken bir haberleşme yöntemi olarak ön plana çıkmaktadır.
Bu çalışmada, veri boyutundaki azalmanın menzil üzerindeki etkilerinin değerlendirilmesi amacıyla; telemetre verileri sıkıştırılarak veri boyutu azaltılmakta ve aktarılması gereken veri miktarındaki azalmanın RF haberleşme menziline etkileri link bütçesi hesabı yapılarak incelenmektedir. Gerçekleştirilen çalışmada, mevcut telemetre formatlarındaki veriler sentetik olarak üretilmiş ve askeri hassasiyette bilgi taşıyan bu verilere çeşitli kayıpsız veri sıkıştırma algoritmaları uygulanarak performansları değerlendirilmiştir. Çalışma kapsamında yapılan hesaplamalarda, RF haberleşmede etkili olabilecek diğer özellikler (örn. modülasyon tipi, almaç özellikleri, anten çeşitleri, vb) sabit tutulmuştur. Elde edilen sonuçlar, aynı sistemlerin kullanılacağı varsayılan testlerde; verinin sıkıştırılması sayesinde veri boyutundaki ve dolayısıyla ihtiyaç duyulan bant genişliğindeki azalmanın haberleşme menzilini arttırdığını göstermektedir.
Dictionary definition of the word ‘telemetry’ is ‘measurement from a distance’. Telemetry notion thus has been used to define the applications aiming to control or observe a system remotely, to record instantaneous data obtained from these systems (via various measurement devices) and to collect all relevant performance data in a data center. Currently, electrical facilities, natural gas production facilities, communication systems, biomedical systems, space stations and vehicles are some of the major areas that use telemetry for their measurements. Also; the design stage of aircrafts, rockets and missiles require telemetry applications as they require validation of design by comparing performance data from actual vehicles.
Telemetry data of a missile in design stage, typically include measurements of various on-board sensors, GPS (Global Positioning System) data, guidance commands created by the missile computer, position of flaps and so on. These data are collected by an internal processor and later transmitted via wireless communication to a ground station, where they can be investigated by the design engineers to see if they align with pre-flight predictions.
In Turkey, there are on-going design and production work for different types of missile projects; created by the needs of Turkish Armed Forces and the state. For the flight tests, different test ranges are assigned according to the requirements of different projects and many telemetry tests are performed with success each year. The collected telemetry data are then used to see if the design engineering was performed in the right way to obtain a missile meeting the requirements of that certain project. This critical role of telemetry tests lead to the importance of collecting as much data as possible with minimum error.
Compression of telemetry data pre-transmission shows itself as an answer to the question of increasing the amount of data obtained per-flight. Literature search for usage of data compression methods for missile/rockets, show results in mostly applications of compression in the data recording/storing stage. However, data bandwidth in missile telemetry tests limit the communication range of the test and amount of information obtained in the test and data compression performed on-board might be a solution for this problem.
This study aims to investigate the effects of data compression, thus decreased data bandwidth on the RF communication range in missile telemetry tests. For this purpose, different data compression methods are performed on fabricated (assumed) telemetry data, the decrease in data amount are compared and effects on RF parameters are investigated using link budget calculations. Other communication parameters such as signal modulation type, receiver specifications, antenna types, etc. are accepted as constants to see the effect of data size only. The results are compatible with the hypothesis; as they show increase in communication range after a decrease in data bandwidth, as expected
İvmeölçer sinyallerinin ileri yöntemlerle analizi
No full textBu çalışmada, titreşim analizi için kullanılan ivmeölçerli sinyallerin ürettiği durağan olmayan sinyallerin tanımlanması ve kestirilmesi amaçlanmıştır. Öncelikle ataletsel ölçüm birimi üzerindeki ivmeölçerden her üç eksende (x, y, z) ivmeölçer değerleri okunarak deneysel veri kümesi oluşturulmuştur. Ataletsel ölçüm birimi aracılığıyla elde edilen bu deneysel verinin çeşitli hatalar içerdiği gözlenmiştir. Bu hatalar deterministik (sistematik) ve olasılıksal (rasgele) olarak iki ayrı grupta incelenmiştir.
Bu araştırmada zaman tanım bölgesinde çalışan yöntemler tercih edilmiştir. Bunun nedeni frekans tanım bölgesine geçerken kullanılan dönüşüm tekniklerinin içerdiği yöntemsel hatalardan (Örneğin Fourier dönüşümünün sınır değerler ve yayılma-smearing problemleri) kaçınmaktır. Bu yöntemsel hatalar her dönüşüm ve ters-dönüşüm operasyonunda katlanarak artmıştır. Öncelikle Kalman süzgeci, iki farklı model için incelenerek deneysel verilerden hız ve konum bilgisi kestirilmiştir.
Ayrıca yakınsama özellikleri, Kalman kazancının ve durum hata ortak değişintisinin normlarının belirli bir değere yakınsadığı, dolayısı ile kestirim hatasının minimize edildiği kanıtlanmıştır. Allan varyans yöntemi kullanılarak zamanla değişen varyans hesaplanarak, olasılıksal hata karakterizasyonu yapılmıştır.
This study aimed to identify non-stationary signals produced by accelerometer used for vibration analysis and prediction. First, the experimental data set was generated by reading the accelerometer values of all three axes (x, y, z) from the accelerometer on the inertial measurement unit. This experimental data obtained through the inertial measurement unit contains various errors. These errors can be studied in two separate groups as deterministic (systematic) and stochastic (random). In this study, the methods are operated in the time domain, are preferred. The reason for this is to avoid methodological errors (such that Fourier transform's boundary value and smearing problems) that are caused by the conversion techniques used in transformation to the frequency domain. These errors increase in each conversion and in the reverse-conversion operation. Firstly, Kalman filter is examined for two different models and speed and position information are estimated from experimental data. In the mean time, by examining convergence properties of the filter, norms of Kalman gain and state error covariance matrix are converged to certain value, that proves the minimization of the estimation error. Characterization of stochastic errors was performed by calculating the time varying variance by Alllan variance method
Ataletsel ölçüm birimi hata analizi ve modellenmesi
No full textAtaletsel navigasyon sistemi, navigasyon denklemleri üzerinden ataletsel ölçüm birimi algılayıcı çıktılarını kullanarak konum, hız, ivme ve yönelim hesaplamaktadır. Hız değerlerin elde edilmesi için gerekli tümlev alma işlemleri sonucu biriken algılayıcı hataları ve sistemin yanlış modellenmesi, uzun süren navigasyon uygulamalarında, bir sonraki durumun kestirilmesinde kritik öneme sahiptir. Bu durum, kestirim için kullandığımız Kalman filtresi yapısını etkilemektedir. Kalman filtresi, durum uzay modeli ile temsil ettiğimiz sistemde, modelin önceki bilgileri ile giriş ve çıkış bilgilerinden sistemimizin durumlarını tahmin edilebilen başarılı bir filtredir.
Bu tez çalışmasının amacı, geliştirilen ve güçlendirilerek adaptif hale getirilen Kalman Filtresi algoritması ile ataletsel navigasyon için kestirim hatalarını minumum değerlere indirerek sistem performansının artırılmasıdır. Unutma faktörü ile adaptif hale getirilen Kalman filtresi algoritması denenip, geleneksel Kalman filtresi ile karşılaştırılacaktır. Hata kompanzasyonu sonrasında, doğruluk analizi ile performans karşılaştırması yapılacaktır. Sistem modelinin hatalı ve hatasız olarak kurulması sonucu iki farklı durum için karşılaştırma yapılmıştır.
Imu01b ataletsel algılayıcısı, Arduino denetleyicisi üzerinden I2C haberleşme protokolü ile alınan ivme değerleri Matlab benzetim ortamına aktarılarak tasarlanan adaptif Kalman algoritmasının performası değerlendirilmiştir.
The working principle of Inertial navigation system, determines acceleration, velocity, position and attitude by using navigation equations and inertial sensor outputs.For calculation of these values, accumulation of sensor errors propagated by integration and wrong modelling of the system become very crucial in long-term applications and estimating the next state.
The Kalman Filter is filtered in a dynamic system, which is represented by the state space model, in which the state of the system can be estimated from input and output information along with the model's previous information. The purpose of this thesis is to developed and enhanced by adapting of the Kalman Filter algorithm, increases the system performance by decreasing the estimation errors for inertial navigation. For this, adaptive Kalman filter algorithm tried and compared to classic Kalman filter. After the error compensation, accuracy analysis and performance comparison will be done.
Imu01b inertial sensor, acceleration values obtained by I2C communication protocol via Arduino controller are transferred to matlab simulation environment so the performance of the adaptive Kalman algorithm has been evaluated
Prevalence of Proteinuria in School-Aged Turkish Children, and Its Association with Obesity and Hypertension
No full textAim: In kidney diseases, renal damage may be mild and initially asymptomatic. Proteinuria, a marker of kidney injury, directly contributes to chronic tubulointerstitial damage. We investigated the prevalence of proteinuria (POP) in school-aged children in Turkey.
Materials and Methods: The cluster sampling method was used to calculate the required size of the study group for this cross-sectional study. Urine samples were randomly obtained to determine urinary protein/creatinine ratio (Upr/Ucr) from 1374 children aged 6 to 18 years. POP was also specifically assessed in hypertensive and obese children.
Results: The mean age of the subjects was 11.68 +/- 3.43 years. The children were from rural (23.9%) and urban (76.1%) regions of Tokat, Turkey. Upr/Ucr >= 0.20 was detected in 92 children, corresponding to a POP rate of 6.7%, without any statistically significant difference between girls and boys. Among 141 obese children, 16 (11.3%) and 76 of 1233 non-obese children (6.2%) had proteinuria (p0.05).
Conclusion: Among school-aged Turkish children POP was 6.7%. POP was higher in obese than in non-obese children. But there was no association between POP and hypertension. While screening programs allow the early detection of renal disease, further cohort studies are required to be able to suggest urinary screening programs
The Effect of Pycnogenol (R) on Spatial Learning and Memory in Rats with Experimental Closed Head Injury
No full textAim: Trauma is a leading cause of emergency admissions. In this study, we investigated the effect of Pycnogenol (R) on spatial learning and memory (SLM) function in rats subjected to closed head injury.
Methods: The study was a randomized, experimental study of four groups, each containing six rats. Pycnogenol (R) was administered to rats in two groups (group three and four) daily for five days starting on day one. A Barnes maze was used to test SLM in the rats in all four groups. Group 1: These rats did not have a closed head injury and were not administered Pycnogenol (R). Group 2: On the day three, closed head trauma was inflicted. Group 3: Pycnogenol (R) was administered to the rats. On day three, closed head trauma was inflicted. Group 4: Only Pycnogenol (R) was administered. At the end of day five, the brain tissue of the 24 rats was removed.
Results: There were no significant differences between the groups in mean SLM durations on days one through five. No significant differences were detected in the pathological examination between of the four groups.
Conclusion: Future studies that employ biochemical markers and free radical levels in the brain are needed
Duodenitis caused by Sarcina ventriculi in a case with Celiac disease and selective IgA deficiency
No full textSarcina ventriculi is a gram-positive, obligate anaerobic bacteria first documented in the human gastrointestinal tract in 1842. Sarcina ventriculi are found to be associated with delayed gastric emptying and gastric outlet obstruction Up to date numerous cases of fatal disease have been attributed to this organism in the veterinary literature, but only a few human cases have been documented. Herein we report a case of a 10-year-old girl patient who was diagnosed Celiac disease, selective IgA deficiency and Sarcina ventriculi duodenitis. To the best of our knowledge the association Celiac disease and Sarcina ventriculi duodenitis has not been previously reported in children. Therefore, in the present study we want to draw attention to the importance of a rare coexistance of Celiac disease and Sarcina ventriculi duodenitis
Effects of Addition of Preoperative Intravenous Ibuprofen to Pregabalin on Postoperative Pain in Posterior Lumbar Interbody Fusion Surgery
No full textObjective. Ibuprofen and pregabalin both have independent positive effects on postoperative pain. The aim of the study is researching effect of 800 mg i.v. ibuprofen in addition to preoperative single dose pregabalin on postoperative analgesia and morphine consumption in posterior lumbar interbody fusion surgery. Materials and Methods. 42 adult ASA I-II physical status patients received 150 mg oral pregabalin 1 hour before surgery. Patients received either 250 ml saline with 800 mg i.v. ibuprofen or saline without ibuprofen 30 minutes prior to the surgery. Postoperative analgesia was obtained by morphine patient controlled analgesia (PCA) and 1 g i.v. paracetamol every six hours. PCA morphine consumption was recorded and postoperative pain was evaluated by Visual Analog Scale (VAS) in postoperative recovery room, at the 1st, 2nd, 4th, 8th, 12th, 24th, 36th, and 48th hours. Results. Postoperative pain was significantly lower in ibuprofen group in recovery room, at the 1st, 2nd, 36th, and 48th hours. Total morphine consumption was lower in ibuprofen group at the 2nd, 4th, 8th, 12th, and 48th hours. Conclusions. Multimodal analgesia with preoperative ibuprofen added to preoperative pregabalin safely decreases postoperative pain and total morphine consumption in patients having posterior lumbar interbody fusion surgery, without increasing incidences of bleeding or other side effects
Does severe osteoarthritis in knees with varus deformity alter the adductor ratio?
No full textObjective: In our retrospective study, we aimed to investigate the differences between the adductor ratio (AR) in knees with and without osteoarthritis, and its validity in determining the articular level.
Methods: Data from 80 knees of 80 patients were retrospectively evaluated. Anteroposterior weight bearing knee radiographs of the patients with and without osteoarthritis (40 knees in each group) were obtained. The adductor ratio was determined using the following formula: ATJL/FW (adductor tubercle-joint line distance/femoral width). All radiographs were evaluated at the baseline and at one-month intervals afterwards. Intraobserver reliability of the two measurements was assessed using interclass correlations (ICC). Pearson's correlation test was used to evaluate the correlation between the ATJL and the FW. The differences between the adductor ratios of the two groups were evaluated by the independent samples two-tailed t-test.
Results: Most of the ICC values were well above 0.95, indicating a very high intraobserver reliability. The adductor ratio was significantly greater in Group 2 in comparison to Group 1 (Mean AR in Group 2: 0.522 +/- 0.031 and Mean AR in Group 1: 0.502 +/- 0.032; p = 0.005). There was a significant correlation between the ATJL and FW in the groups when assessed both separately and combined.
Conclusion: In conclusion, we can assert that if the AR is used to determine the articular level in revision arthroplasty cases, it may be sensible to measure the FW intraoperatively rather than measuring it on primary or contralateral radiographs of arthritic patients. (c) 2017 Turkish Association of Orthopaedics and Traumatology. Publishing services by Elsevier B.V