The effect of engineering design based stem education on the problemsolving skills of pre-school students

Bu çalışmanın amacı mühendislik tasarımına dayalı STEM eğitiminin okul öncesi eğitim gören çocukların problem çözme becerileri üzerine etkisini ortaya çıkarmaktır. Araştırma yöntemi olarak durum çalışması yöntem türlerinden biri olan açıklayıcı durum çalışması yöntemi benimsenmiştir. Çalışma gurubu olasılığa dayalı olmayan (yargısal) örneklem seçim yöntemi esas alınarak belirlenmiş ve bir devlet okulunda görev yapan iki okul öncesi öğretmen ve onların öğrencileri ve velilerden oluşturulmuştur. Nicel verileri toplama aracı olarak Oğuz ve Akyol (2015) tarafından geliştirilmiş olan ‘‘5-7 Yaş Çocuklar İçin Problem Çözme Becerisi Ölçeği’’ kullanılırken nitel verileri toplamak için ise öğretmen ve velilerle yarı yapılandırılmış mülakat yürütülmüştür. Elde edilen bulgulara göre mühendislik tasarımına dayalı STEM eğitimin okul öncesi çocuklarının problem çözme becerilerinin gelişimine önemli katkısının olduğu tespit edilmiştir. Diğer taraftan ailelerin de STEM etkinliklerine katılmaları çocukların problem çözme becerilerinin gelişimi açısından oldukça faydalı olacağından ailelerin de yer aldığı bir araştırma yürütülebilir.The aim of this study is to reveal the effect of STEM education based on engineering design on problem solving skills of pre school children. As a research method, explanatory case study method, one of the case study method types, was adopted. The study group was determined on the basis of the non-probabilistic (judicial) sampling method and consists of two pre-school teachers and their students and parents working in a public school. As a means of collecting quantitative data, the "Problem Solving Skills Scale for 5-7 Years Old Children" developed by Oğuz and Akyol (2015) was used, and a semistructured interview was conducted with teachers and parents to collect qualitative data. According to the findings, it was determined that STEM education based on engineering design has a significant contribution to the development of problem solving skills of preschool children. On the other hand, since the participation of families in STEM activities will be very beneficial for the development of problem solving skills of children, a research including families can be conducted

Rare earth element-bearing fluorite deposits of Turkey: An overview

Rare Earth Element (REE)-bearing fluorite deposits in Turkey occur in association with Cenozoic post-collisional alkaline-carbonatite systems and can be divided into three groups: (1) carbonatite-associated; (2) those associated with subalkaline to alkaline magmatic rocks of Cretaceous to Cenozoic age; and (3) those in sedimentary successions, typically in areas dominated by limestone. Some of these deposits show significant enrichment in the REE, especially the Kızılcaören deposit which has average REE grades of almost 30,000 ppm; others have very low REE contents but have potential fluorite resources. The homogenization temperature and salinity values of fluid inclusions in these deposits vary between 600 °C and 150 °C, and 10–65 wt% NaCl eq., respectively. The carbonatite-associated deposits have the highest bulk REE contents and are LREE-enriched. As a general feature, the REE contents of the fluorite deposits decrease with decreasing homogenization temperatures and salinity of the fluorite fluid inclusions. Fluorite ore chemistry indicates that a plot of Nb + Ta versus total REE differentiates the carbonatite- hosted from the alkali intrusive- hosted and carbonate- hosted deposits. Beyond the cooling and/or dilution of the fluids, REE and fluorite deposition was driven by changes in pH, instead of change in Eh, according to our geostatistical treatment. The chondrite-normalized rare earth element patterns of each group of deposits show some similar features, indicating that the REE in the fluorite are independent of their host lithology, but reflect the magmatic systems from which they were derived. Overall, the F-REE deposits of the Anatolides-Taurides in Turkey are considered to be largely related to the post-collisional magmatic systems, but with variable contributions of fluids from other sources

Chronic restraint stress impairs spatial memory while decreasing hippocampal BDNF levels in rats

Aim: This study investigated the potential role of chronic restraint stress (CRS) on spatial memory, recognition memory, brain-derived neurotrophic factor (BDNF) and acetylcholine (ACh) levels in young adult rats. Material and Methods: In the study, 16 female rats of 12 weeks old were used. Rats were divided into two groups as control and CRS (n=8). CRS was applied 5 hours a day for 21 days. Following the end of CRS, recognition memory of rats was evaluated with new object recognition test (NORT) and spatial memory was evaluated with Morris water maze (MWM) test. At the end of the study, rats were euthanized and hippocampal tissue homogenates were obtained. Hippocampal BDNF and ACh levels were determined by ELISA method. Results: Exposure to CRS did not significantly change the exploratory behavior and discrimination index of rats (p > 0.05). In the test phase in which spatial memory was evaluated, CRS decreased the time spent in the target quadrant (p > 0.01). There was no significant difference between days in the training phase. CRS significantly decreased BDNF level in hippocampus (p > 0.05). Hippocampal ACh levels were not statistically significant (p > 0.05). Conclusions: CRS weakened cognitive functions in rats. This effect was mainly accompanied by a decrease in hippocampal BDNF levels. Our findings point to the potential role of BDNF in understanding the molecular mechanism of CRS-induced cognitive impairment

Application of experimental design on determination of aluminum content in saline samples by adsorptive cathodic stripping voltammetry

Adsorptive cathodic stripping voltammetric determination of aluminum at ng mL-1 levels in salt samples based on the metal complexation with Calcon (1-(2-hydroxynaphthylazo)-2 naphthol-4-sulfonic acid) and the subsequent adsorptive deposition onto a hanging mercury drop electrode was studied. Central composite design was used as a design method. Several chemical and instrumental parameters (pH, ligand concentration, deposition time, deposition potential, and complexing time) were involved in the experimental design. Analytical parameters such as repeatability, linearity, and accuracy were also investigated and the detection limit was found as 0.32 ng mL-1.Ege University research fund (Project no: 2004 Fen 071

Agomelatin yetişkin sıçanlarda skopolamin kaynaklı öğrenme ve hafıza bozukluğunu tersine çevirir

Amaç: Agomelatin, melatonin reseptör (MT1 ve MT2) agonisti ve serotonin reseptör (5-HT2C) antagonisti olan antidepresan bir ilaçtır. Artan kanıtlar, agomelatinin nöroprotektif ve nöromodülatör etkiye sahip olduğunu göstermektedir. Bu çalışmada skopolamin indüklü bilişsel yetmezlik oluşturulan sıçanlarda agomelatinin potansiyel etkileri araştırılmıştır. Materyal ve Metot: Erişkin erkek sıçanlara 21 gün süreyle skopolamin (1 mg/kg) ve agomelatin (40 mg/kg) uygulandı. İlaç uygulamalarını takiben sıçanlar bilişsel davranışların değerlendirilebilmesi amacıyla yeni nesne tanıma (YNT) ve Morris su labirenti (MSL) testine tabi tutuldu. İlave olarak, beyin nörokimyasal analizleri için hipokampus ve prefrontal kortekste beyin-türevi nörotrofik faktör (BDNF) ve asetilkolin (ACh) düzeyleri değerlendirildi. Bulgular: Skopolamin hem uzamsal hafızayı hem de ayırt etme indeksini önemli ölçüde azalttı (p<0,05). Agomelatin tedavisi uzamsal hafıza performansını ve keşif süresini arttırdı, ancak ayrımcılık indeksini etkilemedi (P>0,05). Ayrıca agomelatin, skopolamin grubuna kıyasla hem hipokampusta hem de prefrontal kortekste BDNF düzeylerini önemli ölçüde arttırdı (sırasıyla p<0,05, p<0,01). Diğer yandan grupların ACh düzeyleri arasında istatistiksel olarak anlamlılık bulunmadı (p>0,05). Sonuç: Birlikte ele alındığında, bu sonuçlar agomelatinin skopolamin kaynaklı hafıza yetmezliğinin hafifletilmesinde belirgin rol oynadığını göstermiştir. Bu nedenle, agomelatinin bilişsel yetmezliğin önlenmesinde potansiyel bir ajan olabileceğini öne sürüyoruzObjective: The antidepressant agomelatine agent is a melatonin receptor (MT1 and MT2) agonist and a serotonin receptor (5-HT2C) antagonist. Increasing evidence shows that agomelatine has neuroprotective and neuromodulatory effects. In this study, the potential effects of agomelatine in rats with scopolamine-induced cognitive impairment were investigated. Materials and Methods: Adult male rats were administered scopolamine (1 mg/kg) and agomelatine (40 mg/kg) for 21 days. After drug administration, rats were subjected to new object recognition (NOR) and Morris water maze (MWM) tests in order to evaluate cognitive behaviors. In addition, brain-derived neurotrophic factor (BDNF) and acetylcholine (ACh) levels in the hippocampus and prefrontal cortex were evaluated. Results: Scopolamine significantly decreased both spatial memory and discrimination index (p<0.05). Agomelatine treatment increased spatial memory performance and exploration time, but did not affect the discrimination index (P>0.05). In addition, agomelatine significantly increased BDNF levels in both hippocampus and prefrontal cortex compared to the scopolamine group (p<0.05, p<0.01, respectively). On the other hand, there was no statistically significant difference between the ACh levels of the groups (p>0.05). Conclusion: Taken together, these results demonstrated that agomelatine plays a important role in alleviating scopolamine-induced memory impairment. Therefore, we suggest that agomelatine may be a potential agent in the prevention of cognitive impairment

Hepatoprotective potential of chestnut bee pollen on carbon tetrachloride-induced hepatic damages in rats

This study was supported by Research Fund of Karadeniz Technical University (Project no. 2009.111.002.5). Two of the authors, Oktay Yildiz and Huseyin Sahin, were funded by TUBITAK-BIDEB for their graduate studies.Bee pollen has been used as an apitherapy agent for several centuries to treat burns, wounds, gastrointestinal disorders, and various other diseases. The aim of our study was to investigate the hepatoprotective effects of chestnut bee pollen against carbon tetrachloride (CCI4)-induced liver damage. Total phenolic content, flavonoid, ferric reducing/antioxidant power, and DPPH radical activity measurements were used as antioxidant capacity determinants of the pollen. The study was conducted in rats as seven groups. Two different concentrations of chestnut bee pollens (200 and 400 mg/kg/day) were given orally and one group was administered with silibinin (50 mg/kg/day, i.p.) for seven days to the rats following the CCI4 treatment. The protective effect of the bee pollen was monitored by aspartate transaminase (AST) and alanine transaminase (AST) activities, histopathological imaging, and antioxidant parameters from the blood and liver samples of the rats. The results were compared with the silibinin-treated and untreated groups. We detected that CCI4 treatment induced liver damage and both the bee pollen and silibinin-treated groups reversed the damage; however, silibinin caused significant weight loss and mortality due, severe diarrhea in the rats. The chestnut pollen had showed 28.87 mg GAE/g DW of total phenolic substance, 8.07 mg QUE/g DW of total flavonoid, 92.71 mg Cyn-3-glu/kg DW of total anthocyanins, and 9 mg beta-carotene/100 g DW of total carotenoid and substantial amount of antioxidant power according to FRAP and DPPH activity. The results demonstrated that the chestnut bee pollen protects the hepatocytes from the oxidative stress and promotes the healing of the liver damage induced by CCI4 toxicity. Our findings suggest that chestnut bee pollen can be used as a safe alternative to the silibinin in the treatment of liver injuries

Malatya Yöresinde Organik Kayısı Yetiştiriciliği

Bu çalışma, Malatya yöresinde organik tarım tekniğinde yer alan bitki besleme uygulamalarını konvansiyonel uygulamasıyla karşılaştırarak, kayısı yetiştiriciliği için en uygun organik tarım programını oluşturmak amacıyla planlanmıştır. Çalışma 2002-2006 yıllarında Malatya ili Akçadağ ilçesi Karapınar Köyü’nde, 5 yıldır sertifikalı olarak organik tarım yetiştiriciliği yapılan, 15 yaşında, 10x10 m aralık ve mesafede dikilmiş Hacıhaliloğlu kayısı çeşidinden kurulu kayısı bahçesinde yürütülmüştür. Bu bahçenin yakınında, konvansiyonel tarım sisteminin uygulandığı, 15 yaşında ve 10x10 m aralık ve mesafe ile dikilmiş Hacıhaliloğlu kayısı çeşidinden kurulmuş bir üretici bahçesi de kontrol bahçesi olarak kullanılmıştır. Deneme tesadüf blokları deneme desenine göre 3 tekerrürlü ve her tekerrürde 3 ağaç olacak şekilde kurulmuştur. Çalışmada, organik tarım sistemine uygun 5 farklı bitki besleme uygulaması A (Toprağa Ticari Organik Gübre + Toprağa Çiftlik Gübresi + Yeşil Gübre Uygulaması), B (Toprağa Ticari Organik Gübre + Toprağa Humik Asit Uygulaması), C (Toprağa Ticari Organik Gübre + Toprağa Çiftlik Gübresi Uygulaması), D (Toprağa Organik Gübre + Yeşil Gübre Uygulaması) ve E (Toprağa Ticari Organik Gübre + Yaprağa Ticari Organik Gübre Uygulaması) yapılmıştır. Uygulamaların meyve verim ve kalitesi üzerine etkileri ile ekonomik analizleri yapılmıştır. Uygulamaların ortalama ağaç başına ve gövde kesit alanına verim değerleri üzerine etkisi %1 düzeyinde önemli bulunmuştur. En yüksek ağaç başına ve gövde kesit alanına verim değerleri sırası ile 111.30 kg/ağaç ve 0.18 kg/cm2 ile kontrol uygulamasından, organik uygulamalardan ise en yüksek verim 83.09 kg/ağaç ve 0.16 kg/cm2 ile A uygulamasından elde edilmiştir. En düşük verim ise 55.25 kg/ağaç ve 0.10 kg/cm2 ile D uygulamasından elde edilmiştir. Çalışmanın sonucunda, Malatya koşullarında verim, kalite ve net karlılık kriterleri göz önüne alınarak, organik kayısı yetiştiriciliği için A kombinasyonunun (Toprağa Ticari Organik Gübre Uygulaması + Toprağa Çiftlik Gübresi Uygulama + Yeşil Gübre Uygulaması), tavsiye edilebilir ve uygulanabilir en uygun organik kombinasyon olduğu saptanmıştır

Effects of geraniol on anxiety/depression-like behavior and hippocampal cholinergic system in rats

Amaç: Kronik stresin depresyon benzeri davranışları arttırdığı bilinmektedir. Geraniol nöromodülatör ve antidepresan etkileri bilinen doğal bir monoterpendir. Bu çalışma, kronik kısıtlama stresi depresyon modeli sıçanlarda geraniolun kolinerjik sistem üzerine olası etkilerini araştırmak için tasarlanmıştır. Gereç ve Yöntem: Çalışmada erişkin 21 adet dişi sıçan kullanıldı. Sıçanlara 3 hafta süreyle günde 5 saat kısıtlama stresi uygulandı. Geraniol oral gavaj yoluyla 100 mg/kg uygulandı. Stres ve ilaç uygulamalarını takiben açık alan testi ile anksiyete, zorunlu yüzme testi ile depresyon benzeri davranışlar değerlendirildi. Daha sonra sıçanlar ötenazi edilerek hipokampus disekte edildi. Asetilkolin (ACh) ve asetilkolinesteraz (AChE) düzeyleri hipokampal doku homojenatlarında ELISA yöntemi ile belirlendi. Bulgular: Stres maruziyeti anksiyete benzeri davranışı belirgin olarak etkilemedi ancak zorunlu yüzme testlerinde depresyon benzeri davranış parametrelerini uyardı. Geraniolun strese bağlı artan hareketsizlik süresini önemli ölçüde azalttığı tespit edildi (p<0.05). Dahası, stres maruziyeti ve geraniol uygulamasının hipomkampal ACh düzeylerini anlamlı olarak etkilemediği gözlemlendi (p>0.05). Diğer yandan, kronik stres AChE düzeylerini önemli ölçüde azalttı (p<0.05). Geraniol tedavisinin AChE düzeylerini belirgin olarak değiştirmediği tespit edildi (p>0.05). Sonuç: Birlikte ele alındığında, bulgularımız kısıtlama stresinin sıçanlarda depresyon benzeri davranışı uyardığı, geraniol tedavisinin ise antidepresan benzeri etkilerini ortaya koydu. Bununla birlikte, geraniolun antidepresan benzeri etkisinin moleküler mekanizmasının ileri çalışmalarla araştırılmasını öneriyoruz.Objective: It is known that chronic stress increases depression-like behaviors. Geraniol is a natural monoterpene known for its neuromodulatory and antidepressant effects. This study was designed to investigate the possible effects of geraniol on the cholinergic system in chronic restraint stress depression model rats. Materials and Methods: 21 adult female rats were used in the study. Restraint stress was applied to rats for 5 hours a day for 3 weeks. Geraniol was administered at 100 mg/kg by oral gavage. Anxiety was evaluated with the open field test, and depression-like behaviors were evaluated with the forced swimming test following stress and drug administration. Then the rats were euthanized and the hippocampus was dissected. Acetylcholine (ACh) and acetylcholinesterase (AChE) levels were determined in hippocampal tissue homogenates by ELISA method. Results: Stress exposure did not significantly affect anxiety-like behavior, but it stimulated depression-like behavior parameters in forced swimming tests. It was determined that geraniol significantly decreased the increased immobility time due to stress (p<0.05). Moreover, it was observed that stress exposure and geraniol administration did not significantly affect hippocampal ACh levels (p>0.05). On the other hand, chronic stress significantly decreased AChE levels (p<0.05). Geraniol treatment did not significantly change AChE levels (p>0.05). Conclusion: Taken together, our findings revealed that restraint stress induces depression-like behavior in rats, while geraniol treatment has antidepressant-like effects. However, we suggest that the molecular mechanism of the antidepressant-like effect of geraniol be investigated with further studies

İnfektif endokarditin epidemiyolojik, klinik ve prognostik sonuçları: 90 atağın retrospektif kohortu

To evaluate the epidemiological, clinical, microbiological, and echocardiographic features, as well as the prognosis and long- term outcome of patients with infective endocarditis. Methods: The clinical records and follow-up data of 90 endocarditis episodes in 86 patients diagnosed with definite and possible infec- tive endocarditis according to the modified Duke criteria in a tertiary university hospital, between 1998 and 2016, were reviewed. Results: Fifty-six patients were male (65.1%), and the mean age was 49.9 ± 14.3. Native valve endocarditis constituted 62.2% of the cases, while the remaining patients had prosthetic valve endocarditis. The aortic (34.4%) and mitral (24.4%) valves were infected more frequently. Streptococci (27.7%) and staphylococci (24.4%) were the most frequently isolated microorganisms. Embolic complications (35.5%) were the leading cause of morbidity, followed by valve insufficiency (28.8%) and heart failure (21.1%). Valve replacement surgery was performed in 28 patients (31%). The in-hospital mortality rate was 15.1% (n = 13). Chronic renal failure (P = .042) and degenerative valves (P = .036) were significantly associated with mortality. Among 43 of the 73 cases available for telephonic survey, 36 (83.7%) patients were alive and without disease, with a median follow-up of 52.9 (4-163) months. Twenty-five (69.4%) of these patients were younger than 55 years, and 24 (66.6%) had native valve endocarditis. Conclusion: Underlying cardiac conditions and chronic renal failure increase mortality in infective endocarditis, regardless of the patho- gen. Long-term survival seems promising in cases with native valve endocarditis and in younger patients with low rates of comorbidities.İnfektif endokardit tanısıyla izlenen hastaların epidemiyolojik, klinik, mikrobiyolojik, ekokardiyografik özellikleri, prognozu ve uzun dönem sonuçlarını değerlendirmek. Yöntemler: 1998 ve 2016 yılları arasında bir üniversite hastanesinde modifiye Duke kriterlerine göre kesin ve olası infektif endokardit tanısı konan 86 hastanın 90 endokardit atağının klinik kayıtları ve takip verileri retrospektif olarak incelendi. Bulgular: Çalışmamızda hastaların 56’sı (%65,1) erkek ve ortalama yaş 49,9 ± 14,3 idi. Doğal kapak endokarditi olguların %62,2’sini oluştururken, diğerlerinde protez kapak mevcuttu. En sık aort (%34,4) ve mitral (% 24,4) kapak tutulumu saptandı. Etken olarak strep- tokoklar (%27,7) ve stafilokoklar (%24,4) en sık izole edilen mikroorganizmalardı. Tüm komplikasyonlar içinde embolik komplikasyonlar (%35,5) ilk sırada yer almış, bunu kapak yetmezlikleri (%28,8) ve kalp yetmezliği (%21,1) izlemiştir. Hastaların 28’ine (%31) kapak replasman operasyonu yapılmış ve tüm hastalar içinde 13 hasta (%15,1) hastane takibinde kaybedilmiştir. Mortalite kronik böbrek yetmezliği (P = ,042) ve dejeneratif kapak hastalarında (P = ,036) istatistiksel olarak daha anlamlı bulundu. Taburculuk sonrası prognoz ve uzun dönem sonuçlar değerlendirildiğinde sağ kalan 73 hastanın 43’üne ulaşılabilmiş ve bu hastalardan 36’sının (%83,7) ortalama 52,9 ay (4-163) hayatta ve genel durumlarının iyi olduğu, 25 hastanın (%69,4) <55 yaş, 24’ünün (%66,6) doğal kapak endokarditi tanısıyla izlenmiş olduğu görülmüştür. Sonuç: İnfektif endokardit hastalarında altta yatan kalp hastalıkları ve kronik böbrek yetmezliği patojenden bağımsız olarak mortalit- eyi arttırmaktadır. Doğal kapak endokarditi ve komorbiditeleri daha az olan genç yaş hastalarda ise uzun dönem sağkalım umut verici görünmektedir

Post-traumatic stress disorder after terrorist attack in healthcare professionals

INTRODUCTION: On the date of 15 July 2016 a terrorist organization launched a terrorist attack using helicopters and heavy combat weapons in the city centers of Istanbul and Ankara simultaneously. Numerous civilian were hurt and many of them lost their lives during the attacks. Terrorism is a form of combat designed to cause the highest psychological influence on the masses. Post-traumatic stress disorder (PTSD) is one of the most common psychological disorders after such disasters. The aim of this study is to determine the associated risk factors and PTSD rates in healthcare professionals who were on call during the 15 July 2016 terrorist attacks. METHOD: Since the hospital is in a neighbouring the street to where terror attacks occurred, all healthcare professionals ≥ 18 years of age who were on duty that night in the Dr. Ridvan Ege Training and Research Hospital and were auditory or visual witnesses of the event were included in the study as the first group while healthcare professionals who work in the same hospital but were not on duty that night were included as the control group. RESULTS: The mean post-traumatic diagnostic scale stress score of the control group was 11.87. The mean post-traumatic diagnostic scale stress score of the Group 1 was 21.91. There was a significant difference between the groups in terms of posttraumatic diagnostic scale stress score (p &lt; 0.05). While the healthcare professionals on duty on July 15, 2016 (Group 1) had moderate-severe (21.91 ± 5.11) stress disorder, the healthcare professionals who were not at the hospital on July 15, 2016 (Control Group) had moderate stress disorder (11.87 ± 6.86). CONCLUSION: Our country is at risk from the fact that such attacks may be experienced again because of its unique conditions. The results of our work support the data on the high level of exposure to PTSD when exposed to a terrorist attack. For this reason, the identification of the characteristics of pre-traumatic health individuals at risk is useful in planning the presentation of preventive and curative health services. At the same time, there is a need for longer-term work and wider samples to reveal the psychological consequences of such attacks