CMS'deki CASTOR kalorimetresinde kullanılan fotoçoğaltıcı tüplerin kalite kontrol testlerinin yapılması ve sonuçlarının incelenmesi

TEZ7814Tez (Yüksek Lisans) -- Çukurova Üniversitesi, Adana, 2010.Kaynakça (s. 73) var.xi, 74 s. : res. (bzs. rnk.) ; 29 cm.CASTOR, is a sub-detector of the CMS experiment. Cherenkov light is produced by relativistic electrons and positrons passing through quartz plates. This light will be detected by PMTs. Before being mounted on CASTOR, this photomultiplier tubes were tested in Çukurova University laboratory and functional parameters such as time parameters and gain, dark current were analyzed and discussed. This thesis contains the results of quality control tests of the CMS-CASTOR's PMTs.CASTOR, CMS deneyinin bir alt dedektörüdür. Relativistik elektronlar ve pozitronlar kuvars plakalardan geçerken Cherenkov ışınımı oluştururlar. Bu ışınım foto-çoğaltıcı tüpler tarafından dedekte edilecektir. Bu foto-çoğaltıcı tüpler CASTOR'a monte edilmeden önce Çukurova Üniversitesi Yüksek Enerji Fiziği laboratuvarında test edildi ve yanıtlama zaman parametreleri, kazanç, karanlık akım gibi işlevsel parametreler analiz edilerek sonuçları tartışıldı. Bu tez CMS-CASTOR foto-çoğaltıcı tüplerinin kalite kontrol test sonuçlarını içermektedir.Bu çalışma Ç.Ü. Bilimsel Araştırma Projeleri Birimi tarafından desteklenmiştir. Proje No: FEF2009YL29

Effect of Storage Time on Nutrient Composition and Quality Parameters of Corn Silage

This study was carried out to determine the effects of storage duration on nutrient composition and silage quality parameters. Corn was used as silage material. Corn (31.41% dry matter) was harvested at the dough stage and fermented for 90, 104, 118, 132, 146, 160, 174, 188 and 202 days in three trench silos. The samples were brought to laboratory every 14 days. This process was repeated 9 times. After the 132th day, whereas silage crude protein (CP), ether extract (EE), ash and crude fiber (CF) contents decreased, nitrogen free extract (NFE) content increased. Lactic acid concentration of corn silage increased until the 118th day but decreased between the 118th and the 160th days. On the contrary, of decrease in LA concentration, acetic acid concentration increased depending on storage time. Ammonia nitrogen and CO2 concentration of silage increased decreased with progressing time. Storage time had significant influence on Flieg scores. The lowest score was found between days the 104th-118th. In this research, it was observed that there was a change in silage nutrient contents and fermentation characteristics with increasing storage time

Can Ultrasound-Guided Femoral Vein Measurements Predict Spinal Anesthesia-Induced Hypotension in Non-Obstetric Surgery? A Prospective Observational Study

Background and objectives: To investigate whether ultrasound (US)-guided femoral vein (FV) and inferior vena cava (IVC) measurements obtained before spinal anesthesia (SA) can be utilized to predict SA-induced hypotension (SAIH) and to identify risk factors associated with SAIH in patients undergoing non-obstetric surgery under SA. Methods: This was a prospective observational study conducted between November 2021 and April 2022. The study included 95 patients over the age of 18 with an American Society of Anesthesiologists (ASA) physical status score of 1 or 2. The maximum and minimum diameters of FV and IVC were measured under US guidance before SA initiation, and the collapsibility index values of FV and IVC were calculated. Patients with and without SAIH were compared. Results: SAIH was observed in 12 patients (12.6%). Patients with and without SAIH were similar in terms of age [58 (IQR: 19–70) vs. 48 (IQR: 21–71; p = 0.081) and sex (males comprised 63.9% of the SAIH and 75.0% of the non-SAIH groups) (p = 0.533). According to univariate analysis, no significant relationship was found between SAIH and any of the FV or IVC measurements. Multiple logistic regression analysis revealed that having an ASA class of 2 was the only independent risk factor for SAIH development (p = 0.014), after adjusting for age, sex, and all other relevant parameters. Conclusions: There is not enough evidence to accept the feasibility of utilizing US-guided FV or IVC measurements to screen for SAIH development in patients undergoing non-obstetric surgery under SA. For this, multicenter studies with more participants are needed

Learning curve of septoplasty procedure

Objectives: The aim of this study was to investigate possible relationship between surgical experience and septoplasty-related data and to determine the learning curve based on surgery duration. Patients and Methods: The first 60 septoplasty patients of four Ear, Nose and Throat residents who completed an 18-month residency training in our clinic between August 2015 and December 2017 were included in the study. A total of 240 patients (155 males, 85 females; mean age 32.8±10.6 years; range, 17 to 60 years) were evaluated. The first 10 patients were grouped as Group A, 11-20 patients as Group B, 21-30 patients as Group C, 31-40 patients as Group D, 41-50 patients as Group E, and 51-60 patients as Group F. The patients’ files were retrospectively reviewed to obtain information on demographics, postoperative hospital stay, complications, revision operation requirements, and operation time. The mean operation time was calculated. Duration of surgery was used to evaluate the maturity of surgical skills. Results: The mean operation time was 60.0±17.3 min. The mean operation times of the patients in Group A and Group B were significantly longer than that of the patients in Group C, Group D, Group E, and Group F. There was no significant difference between the groups in terms of length of hospital stay, complications, and revision rates. Conclusion: As the surgeon's experience increases, the operation time decreases, and after 20 patients, it reaches the plateau level. Based on these data, it can be concluded that ENT residents should practice more than 20 patients to learn the septoplasty procedure sufficiently

Correlation of Treponemal Chemiluminescent Microparticle Immunoassay Screening Test Signal Strength Values With Reactivity of Confirmatory Testing

Background Automated chemiluminescent microparticle immunoassays (CMIAs) are the most common first step at high-volume laboratories for syphilis screening. If the initial screening test is reactive, 1 more treponemal test is required, resulting in increased cost. In this multicenter study, we aimed to determine the correlation between the CMIA signal-to-cutoff ratio (S/Co) and the confirmatory tests to reduce unnecessary confirmatory testing. Methods Eight hospitals from 5 provinces participated in this study. All laboratories used Architect Syphilis TP CMIA (Abbott Diagnostics, Abbott Park, IL) for initial screening. Treponema pallidum hemagglutination (TPHA), rapid plasma reagin (RPR), and fluorescent treponemal antibody absorption (FTA-ABS) were used as confirmatory tests according to the reverse or European Centre for Disease Prevention and Control algorithms. A receiver operating characteristic analysis was used to determine the optimal S/Co ratio to predict the confirmation results. Results We evaluated 129,346 serum samples screened by CMIA between January 2018 and December 2020. A total of 2468 samples were reactive; 2247 (91%) of them were confirmed to be positive and 221 (9%) were negative. Of the 2468 reactive specimens, 1747 (70.8%) had an S/Co ratio >= 10.4. When the S/Co ratios were >= 7.2 and >= 10.4, the specificity values were determined to be 95% and 100%, respectively. In a subgroup of 75 CMIA-positive patients, FTA-ABS was performed and 62 were positive. Among these FTA-ABS-positive patients, 24 had an S/Co ratio = 10.4, obviating the need for secondary treponemal testing in about 71% of the screening-reactive samples. This would substantially reduce the confirmatory testing volume and laboratory expenses. However, in high-risk group patients with CMIA positive results, S/Co ratio <10.4, and negative TPHA and RPR, FTA-ABS may be used for confirmation

Push and Pull Factors of Why Medical Students Want to Leave Türkiye: A Countrywide Multicenter Study

Phenomenon: Physician immigration from other countries is increasing as developed countries continue to be desirable destinations for physicians; however, the determinants of Turkish physicians’ migration decisions are still unclear. Despite its wide coverage in the media and among physicians in Türkiye, and being the subject of much debate, there is insufficient data to justify this attention. With this study, we aimed to investigate the tendency of senior medical students in Türkiye to pursue their professional careers abroad and its related factors. Approach: This cross-sectional study involved 9881 senior medical students from 39 different medical schools in Türkiye in 2022. Besides participants’ migration decision, we evaluated the push and pull factors related to working, social environment and lifestyle in Türkiye and abroad, medical school education inadequacy, and personal insufficiencies, as well as the socioeconomic variables that may affect the decision to migrate abroad. The analyses were carried out with a participation rate of at least 50%. Findings: Of the medical students, 70.7% had emigration intentions. Approximately 60% of those want to stay abroad permanently, and 61.5% of them took initiatives such as learning a foreign language abroad (54.5%) and taking relevant exams (18.9%). Those who wanted to work in the field of Research & Development were 1.37 (95% CI: 1.22–1.54) times more likely to emigrate. The push factor that was related to emigration intention was the “working conditions in the country” (OR: 1.89, 95% CI: 1.56–2.28) whereas the “social environment/lifestyle abroad” was the mere pull factor for the tendency of emigration (OR: 1.73, 95% CI: 1.45–2.06). In addition, the quality problem in medical schools also had a significant impact on students’ decisions (OR: 2.20, 95% CI: 1.83–2.65). Insights: Although the percentage of those who want to emigrate “definitely” was at the same level as in the other developing countries, the tendency to migrate “permanently” was higher in Türkiye. Improving working conditions in the country and increasing the quality of medical faculties seem vital in preventing the migration of physicians

Can we predict patients that will not benefit from invasive mechanical ventilation? A novel scoring system in intensive care: the IMV mortality prediction score (IMPRES)

KUCUK, Ahmet Oguzhan/0000-0002-6993-0519; Kirakli, Cenk/0000-0001-6013-7330; KUCUK, Mehtap PEHLIVANLAR/0000-0003-2247-4074; Aksoy, Iskender/0000-0002-4426-3342WOS: 000504051300010PubMed: 31655511Background/aim: The present study aimed to define the clinical and laboratory criteria for predicting patients that will not benefit from invasive mechanical ventilation (IMV) treatment and determine the prediction of mortality and prognosis of these critical ill patients. Materials and methods: The study was designed as an observational, multicenter, prospective, and cross-sectional clinical study. It was conducted by 75 researchers at 41 centers in intensive care units (ICUs) located in various geographical areas of Turkey. It included a total of 1463 ICU patients who were receiving invasive mechanical ventilation (IMV) treatment. A total of 158 parameters were examined via logistic regression analysis to identify independent risk factors for mortality; using these data, the IMV Mortality Prediction Score (IMPRES) scoring system was developed. Results: The following cut-off scores were used to indicate mortality risk: 8, very high risk. There was a 26.8% mortality rate among the 254 patients who had a total IMPRES score of lower than 2. The mortality rate was 93.3% for patients with total 1M PRES scores of greater than 8 (P < 0.001). Conclusion: The present study included a large number of patients from various geographical areas of the country who were admitted to various types of ICUs, had diverse diagnoses and comorbidities, were intubated with various indications in either urgent or elective settings, and were followed by physicians from various specialties. Therefore, our data are more general and can be applied to a broader population. This study devised a new scoring system for decision-making for critically ill patients as to whether they need to be intubated or not and presents a rapid and accurate prediction of mortality and prognosis prior to ICU admission using simple clinical data

Atrial Fibrillation Management in Acute Stroke Patients in Türkiye: Real-life Data from the NöroTek Study

Objective: Atrial fibrillation (AF) is the most common directly preventable cause of ischemic stroke. There is no dependable neurology-based data on the spectrum of stroke caused by AF in Turkiye. Within the scope of NoroTek-Turkiye (TR), hospital-based data on acute stroke patients with AF were collected to contribute to the creation of acute-stroke algorithms.Materials and Methods: On May 10, 2018 (World Stroke Awareness Day), 1,790 patients hospitalized at 87 neurology units in 30 health regions were prospectively evaluated. A total of 929 patients [859 acute ischemic stroke, 70 transient ischemic attack (TIA)] from this study were included in this analysis.Results: The rate of AF in patients hospitalized for ischemic stroke/TIA was 29.8%, of which 65% were known before stroke, 5% were paroxysmal, and 30% were diagnosed after hospital admission. The proportion of patients with AF who received "effective" treatment [international normalization ratio >= 2.0 warfarin or non-vitamin K antagonist oral anticoagulants (NOACs) at a guideline dose] was 25.3%, and, either no medication or only antiplatelet was used in 42.5% of the cases. The low dose rate was 50% in 42 patients who had a stroke while taking NOACs. Anticoagulant was prescribed to the patient at discharge at a rate of 94.6%; low molecular weight or unfractionated heparin was prescribed in 28.1%, warfarin in 32.5%, and NOACs in 31%. The dose was in the low category in 22% of the cases discharged with NOACs, and half of the cases, who received NOACs at admission, were discharged with the same drug.Conclusion: NoroTekTR revealed the high but expected frequency of AF in acute stroke in Turkiye, as well as the aspects that could be improved in the management of secondary prophylaxis. AF is found in approximately one-third of hospitalized acute stroke cases in Turkiye. Effective anticoagulant therapy was not used in three-quarters of acute stroke cases with known AF. In AF, heparin, warfarin, and NOACs are planned at a similar frequency (one-third) within the scope of stroke secondary prophylaxis, and the prescribed NOAC dose is subtherapeutic in a quarter of the cases. Non-medical and medical education appears necessary to prevent stroke caused by AF

Gastrostomy in hospitalized patients with acute stroke: "NoroTek" Turkey point prevalence study subgroup analysis

Objective: Nutritional status assessment, dysphagia evaluation and enteral feeding decision are important determinants of prognosis in acute neurovascular diseases. Materials and Methods: NöroTek is a point prevalence study conducted with the participation of 87 hospitals spread across all health sub regions of Turkey conducted on 10-May-2018 (World Stroke Awareness Day). A total of 972 hospitalized neurovascular patients [female: 53%, age: 69±14; acute ischemic stroke in 845; intracerebral hematoma (ICH) in 119 and post-resuscitation encephalopathy (PRE) in 8] with complete data were included in this sub-study. Results: Gastrostomy was inserted in 10.7% of the patients with ischemic stroke, 10.1% of the patients with ICH and in 50% of the patients with PRE. Independent predictors of percutaneous endoscopic gastrostomy (PEG) administration were The National Institutes of Health Stroke Scale score at admission [exp (β): 1.09 95% confidence interval (CI): 1.05-1.14, per point] in ischemic stroke; and mechanical ventilation in ischemic [exp (β): 6.18 (95% CI: 3.16-12.09)] and hemorrhagic strokes [exp (β): 26.48 (95% CI: 1.36-515.8)]. PEG was found to be a significant negative indicator of favorable (modified Rankin’s scale score 0-2) functional outcome [exp (β): 0.032 (95% CI: 0.004-0.251)] but not of in-hospital mortality [exp (β): 1.731 (95% CI: 0.785-3.829)]. Nutritional and swallowing assessments were performed in approximately two-thirds of patients. Of the nutritional assessments 69% and 76% of dysphagia assessments were completed within the first 2 days. Tube feeding was performed in 39% of the patients. In 83.5% of them, tube was inserted in the first 2 days; 28% of the patients with feeding tube had PEG later. Conclusion: The NöroTek study provided the first reliable and large-scale data on key quality metrics of nutrition practice in acute stroke in Turkey. In terms of being economical and accurate it makes sense to use the point prevalence method.Amaç: Akut nörovasküler hastalıklarda nütrisyonel durum ve disfaji değerlendirmesi ve enteral beslenme kararı önemli prognoz belirleyicilerindendir. Gereç ve Yöntem: NöroTek, 10 Mayıs 2018’de (Dünya İnme Farkındalık Günü) Türkiye’nin tüm sağlık alt bölgelerine yayılmış 87 hastanenin katılımıyla gerçekleştirilen bir nokta prevalans çalışmasıdır. Hastanede yatan ve bu alt çalışma için toplanan verisi tam olan toplam 972 nörovasküler hasta (kadın: %53, yaş: 69±14 yıl; 845’i akut iskemik inme; 119’u intraserebral hematom ve 8’i post-resüsitasyon ensefalopatisi) analiz edildi. Bulgular: Gastrostomi iskemik inmeli hastaların %10,7, intraserebral kanamalıların %10,1 ve post-resusitasyon ensefalopatisi olanların %50’sine uygulanmıştır. Perkütan endoskopik gastrostomi (PEG) gereksiniminin bağımsız belirleyicileri, iskemik inme grubunda kabul NIHSS [exp (β): 1,09, %95 güven aralığı (GA): 1,05-1,14, puan başına] ile hem iskemik hem de hemorajik inmelerde mekanik ventilasyon uygulanmış olmasıdır [iskemik için: exp (β): 6,18, %95 GA: 3,16- 12,09] ve hemorajik inme için: [exp (β): 26,48, 95% GA: 1,36-515,8]. İnme olgularında PEG uygulaması hastane içi mortalite için bağımsız belirleyici değildi [exp (β): 1,731, 95% GA: 0,785-3,829]. Ancak, PEG uygulanmış olması taburculuk esnasında iyi prognoza (modifiye Rankin skoru 0-2) sahip olabilme için anlamlı bir negatif etmen olarak bulundu [exp (β): 0,032, %95 GA: 0,004-0,251]. Hastanede yatan nörovasküler hastaların yaklaşık üçte ikisinde malnütrisyon ve yutma bozukluğu açısından değerlendirme yapılmıştı. Nutrisyonel status değerlendirmesinin %69’u ve disfaji değerlendirmesinin %76’sı ilk 48 saat içinde gerçekleştirilmişti. Tüple enteral nütrisyon uygulama oranı %39’du. Beslenme tüplerinin %83,5’i ilk 2 gün içinde yerleştirilirken beslenme tüpü olan hastaların %28’ine daha sonra PEG açılmıştı. Sonuç: NöroTek çalışması ile Türkiye’de hastanede yatan akut inme hastalarında nutrisyonel uygulamaların temel kalite ölçütlerine ilişkin ilk güvenilir ve büyük ölçekli veri sağlanmıştır. Ekonomik olması ve doğruluğu açısından nokta yaygınlık yönteminin bu tip verilerin temini için daha fazla kullanılması mantıklıdır