352 research outputs found
Drying characteristics of bay laurel (Laurus nobilis L.) fruits in a convective hot-air dryer
In this study, drying characteristics of bay laurel (Laurus nobilis L.) fruits were investigated in a laboratory scale hot-air dryer at air temperature in a range of 70 to 100°C. Moisture transfer from the test samples was described by applying the Fick’s diffusion model and the effective diffusivity was calculated. Temperature dependence of the effective diffusivity was described by the Arrhenius-type relationship. The experimental drying data of bay laurel fruits were used to fit page, logarithmic, Twoterm and approximation of diffusion, and Midilli et al. (2002) models and the statistical validity of models tested were determined by non-linear regression analysis. The Two-term model showed a better fit to experimental drying data obtained when compared with other models.Key words: Bay laurel fruits, convective air drying, moisture ratio, effective diffusivity, activation energy
Effect of Low-flow Anesthesia Education on Knowledge, Attitude and Behavior of the Anesthesia Team
AbstractThe aim of this study was to evaluate the effect of education on the knowledge, attitude and behavior of anesthesiology staff and residents towards low-flow anesthesia. The staff and residents in the Department of Anesthesia and Reanimation, Zonguldak Karaelmas University were given theoretical and practical training in delivering low-flow anesthesia. To evaluate their attitudes and behaviors toward low-flow anesthesia, we collected data during the 6 months before training, during the first 3 months after training, and at 4–6 months after training. Anesthesia follow-up records, operation time, volatile anesthetic agent used, and the amount (in liters) of fresh gas low mid-anesthesia were recorded in all three stages. A total of 3,158 patients received general anesthesia and inhalation anesthesia was used in 3,115 of these patients. Our study group consisted of 2,752 patients who had no absolute or relative contraindications to low-flow anesthesia. While the mean fresh gas flow was 4.00 ± 0.00 L/min before training, this level dropped to 2.98 L/min in the first 3 months after training, and to 3.26 L/min in the following 3 months. The mean fresh gas flow was significantly lower at the two post-training assessments than before training (p < 0.05). In conclusion, low-flow anesthesia may be used more frequently if educational seminars are provided to anesthetists. The use of low-flow anesthesia may increase further by allocating more time to this technique in anesthesia training programs provided at regular intervals
Efectos del mantenimiento de varias anestesias sobre los niveles séricos de selenio, cobre, cinc y hierro y la capacidad antioxidante
ResumenJustificación y objetivosInvestigar los efectos del mantenimiento de sevoflurano, desflurano y propofol sobre los niveles séricos de selenio, cobre, cinc, hierro y malondialdehído, las medidas de glutatión peroxidasa y la capacidad antioxidante.MétodosFueron ubicados en 3 grupos 60 pacientes programados para cirugía unilateral de miembros inferiores, realizada con torniquete bajo anestesia general. Fueron recogidas muestras de sangre para determinar los niveles séricos basales de selenio, cobre, cinc, hierro, malondialdehído y glutatión peroxidasa. La anestesia fue inducida con 2-2,5mg/kg−1 de propofol, 1mg/kg−1 de lidocaína y 0,6mg/kg−1 de rocuronio. En el mantenimiento de la anestesia, bajo gas portador de 50% de O2 y 50% de N2O (4L/min−1), sevoflurano a 1CAM fue administrado al grupo S; y desflurano a 1CAM al grupo D y bajo gas portador en mezcla de 50% O2 y 50% aire (4L/min−1), 6mg/kg/h−1 de propofol y 1μg/kg/h−1 de fentanilo fueron administrados al grupo P. En el postoperatorio se recogieron de nuevo muestras de sangre.ResultadosSolamente en los grupos S y P los niveles de malondialdehído disminuyeron en las 48h del postoperatorio; los niveles de glutatión peroxidasa aumentaron en comparación con los valores basales. Los niveles de selenio disminuyeron en el grupo S y en el grupo P, los niveles de cinc disminuyeron en el grupo P, los de hierro disminuyeron en todos los grupos y no hubo alteración en los niveles de cobre en ningún grupo en el período postoperatorio.ConclusiónDe acuerdo con los marcadores de malondialdehído y glutatión peroxidasa, llegamos a la conclusión de que el mantenimiento de la anestesia general con propofol y sevoflurano activó el sistema antioxidante contra el estrés oxidativo y el uso de desflurano no tuvo efectos sobre el estrés oxidativo y el sistema antioxidante.AbstractBackground and objectivesIn this study, we aimed to investigate the effects of sevoflurane, desflurane and propofol maintenances on serum levels of selenium, copper, zinc, iron, malondialdehyde, and glutathion peroxidase measurements, and antioxidant capacity.Methods60 patients scheduled for unilateral lower extremity surgery which would be performed with tourniquet under general anesthesia were divided into three groups. Blood samples were collected to determine the baseline serum levels of selenium, copper, zinc, iron, malondialdehyde and glutathion peroxidase. Anesthesia was induced using 2-2.5mg/kg−1 propofol, 1mg/kg−1 lidocaine and 0.6mg/kg−1 rocuronium. In the maintenance of anesthesia, under carrier gas of 50:50% O2:N2O 4L/min−1, 1MAC sevoflorane was administered to group S and 1MAC desflurane to group D; and under carrier gas of 50:50% O2:air 4L/min−1 6mg/kg/h−1 propofol and 1μg/kg/h−1 fentanyl infusion were administered to group P. At postoperative blood specimens were collected again.ResultsIt was observed that only in group S and P, levels of malondialdehyde decreased at postoperative 48th hour; levels of glutathion peroxidase increased in comparison to the baseline values. Selenium levels decreased in group S and group P, zinc levels decreased in group P, and iron levels decreased in all three groups, and copper levels did not change in any groups in the postoperative period.ConclusionAccording to the markers of malondialdehyde and glutathion peroxidase, it was concluded that maintenance of general anesthesia using propofol and sevoflurane activated the antioxidant system against oxidative stress and using desflurane had no effects on oxidative stress and antioxidant system
Effectiveness of sugammadex for cerebral ischemia/reperfusion injury
AbstractCerebral ischemia may cause permanent brain damage and behavioral dysfunction. The efficacy and mechanisms of pharmacological treatments administered immediately after cerebral damage are not fully known. Sugammadex is a licensed medication. As other cyclodextrins have not passed the necessary phase tests, trade preparations are not available, whereas sugammadex is frequently used in clinical anesthetic practice. Previous studies have not clearly described the effects of the cyclodextrin family on cerebral ischemia/reperfusion (I/R) damage. The aim of this study was to determine whether sugammadex had a neuroprotective effect against transient global cerebral ischemia. Animals were assigned to control, sham-operated, S 16 and S 100 groups. Transient global cerebral ischemia was induced by 10-minute occlusion of the bilateral common carotid artery, followed by 24-hour reperfusion. At the end of the experiment, neurological behavior scoring was performed on the rats, followed by evaluation of histomorphological and biochemical measurements. Sugammadex 16 mg/kg and 100 mg/kg improved neurological outcome, which was associated with reductions in both histological and neurological scores. The hippocampus TUNEL (terminal deoxynucleotidyl transferase dUTP nick end labeling) and caspase results in the S 16 and S 100 treatment groups were significantly lower than those of the I/R group. Neurological scores in the treated groups were significantly higher than those of the I/R group. The study showed that treatment with 16 mg/kg and 100 mg/kg sugammadex had a neuroprotective effect in a transient global cerebral I/R rat model. However, 100 mg/kg sugammadex was more neuroprotective in rats
Clinical effectiveness and cost-effectiveness results from the randomised controlled Trial of Oral Mandibular Advancement Devices for Obstructive sleep apnoea–hypopnoea (TOMADO) and long-term economic analysis of oral devices and continuous positive airway pressure
Uranyum geri kazanılmasında bentonit kullanımının incelenmesi
Nükleer teknolojide, tıpta, değişik sektörlerden kaynaklanan ağır metallerinin uzaklaştırılmasında son zamanlarda adsorpsiyon yöntemi önemli yer tutmaktadır. Çözünen metalik türlerin killer, oksitler ve kolloidal materyallerle adsorpsiyonu, heterojen sistemlerde metal iyon konsantrasyonlarının kontrol edilmesinde önemli görülmektedir. Bu çalışmada, adsorban olarak bir kil çeşidi olan Çankırı doğal bentoniti kullanılmıştır. Çankırı bentonitinin uranyum alım kapasiteleri belirlenmiştir. Isıl işlemlerle aktif hale getirilen, Çankırı bentoniti üzerine, kesikli sistemde, sulu çözeltiden uranyum (VI) iyonlarının adsorpsiyonu incelenmiştir. Çankırı bentoniti üzerine, çözelti pHʼı, uranyumun (VI) başlangıç konsantrasyonu, sıcaklık ve çalkalama süresi, farklı katyon ve anyonların fonksiyonu olarak uranyum (VI) iyonlarının adsorpsiyonu incelenmiş; dağılım katsayıları (Kd) ve adsorpsiyon verimleri (%) saptanmıştır. Adsorpsiyon verilerinin adsorpsiyon izotermlerine uygunluğu araştırılmış; adsorpsiyon entalpisi, entropisi ve serbest enerji değişimi gibi termodinamik parametreler hesaplanmıştır. Çankırı bentonitinden uranyumun geri alınabilmesi için 11 çeşit geri alım reaktifi denenmiş; HNO3ʼin değişen konsantrasyonlarında geri alım denemeleri gerçekleştirilmiştir
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