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The effect of biceps tenotomy on superior humeral migration in arthroscopic repaired full-thickness supraspinatus tears
Full text linkLesions of the long head of the biceps (LHB) tendon are a prevalent injury that frequently coexists with rotator cuff injuries. This study aimed to assess the effect of supraspinatus (SST) repair with concurrent LHB tenotomy on superior migration of the humeral head. The acromiohumeral distance (AHD) was determined via ultrasound to evaluate the superior migration of the humeral head. Methods: The study population was retrospectively recruited from patients who underwent unilateral arthroscopic repair of isolated degenerative full-thickness SST tears between January 2017 and December 2019. Patients were divided into 2 subgroups based on whether they underwent LHB tenotomies during arthroscopy. While 37 patients underwent arthroscopic single-row SST repair, the other 33 patients underwent arthroscopic single-row SST repair with LHB tenotomy. The subject group consisted of people who had undergone arthroscopic shoulder surgery. Contralateral shoulders without rotator cuff injuries were included in the control group. The AHD and SST thicknesses of patients were examined via the ultrasound in both groups and subgroups. Results: The mean age in the SST repair group was 55.52 ± 4.58 years (range, 46-63 years), whereas it was 58.24 ± 3.98 (range, 52-73 years) in the SST repair + LHB tenotomy group. In the SST repair group, 57.6% of patients were female and 42.4% were male, whereas 56.8% and 43.2% were in the SST repair + LHB tenotomy group, respectively. The mean body mass index was 28.06 ± 1.31 kg/m2 (range, 25.7-31.2 kg/m2) in the SST repair group and 28.95 ± 1.79 kg/m2 in the SST repair + LHB tenotomy group. Groups were not different for sex, surgery side, dominant side, tear size, and follow-up time; however, the SST repair + LHB tenotomy group had significantly higher mean age and body mass index than the SST repaired group. The mean AHD value and SST thickness were significantly less in both the rotator cuff repair group and the rotator cuff repair + LHB tenotomy group compared to the healthy shoulder. The mean AHD value was significantly lower in the SST repaired + LHB tenotomy group than in the SST repair group (P = .02). Conclusion: The AHD was narrowed in patients who underwent LHB tenotomy and radiologically demonstrated the depressor effect of the LHB tendon on the humeral head. As a secondary outcome, we demonstrated that regardless of tenotomy, AHD could not be restored in patients who underwent arthroscopic single-row SST repair
Ammonia free catalytic reduction of nitric oxide on Ni-embedded graphene nanostructure: A density functional theory investigation
No full textIn this study, the catalytic reduction reaction of NO (directly) without the presence of ammonia (NH3) was studied on the Ni-embedded graphene (Ni@GN) layer using periodic Density Functional Theory (DFT) calculations. Ni-embedded graphene surface can be synthesized experimentally and it is predicted that it will cost much less than single crystal surfaces due to the economic usage of the transition metal atoms. First of all, by optimizing the geometric structure of the Ni@GN layer, crucial geometric features and electron density differences (EDD) were obtained. Based on the different adsorption configurations of NO molecule, the reduction reaction was investigated by Langmuir-Hinshelwood (L-H) and Eley-Rideal (E-R) based mechanisms. Finally, N2O degradation was analyzed in detail. It is shown that the Eley-Rideal model is a more dominant mechanism on the Ni@GN surface than the other model. In addition, all proposed reaction pathways for NO reduction are exothermic. This information can be used for the research and development of graphene-based materials for NO reduction; paves the way for finding new Ni-based catalysts based on active single transition metal atom embedded on different kind of defects
The evaluation of target markets for hazelnut exports with the classification approach of potential market alternatives
No full textThe aim of the proposed classification approach of potential market alternatives (CAPMA) is to provide exporting countries with a framework for identifying potential market opportunities for their products or services. Design/methodology/approach: In today's global market conditions, with competition increasing daily, companies, businesses and states must seek new markets at the national and international level. Target market selection is a strategic process that directly affects the success of an organization and can lead to important results in the short and long term. The process requires systematic research and digitization of data to analyse target markets. Findings: The study tested the proposed approach by analysing Turkey's potential markets for hazelnut exports and identifying new target markets. A significant part of Turkey's hazelnut exporting is confined to the European geography of Turkey, the leading country in hazelnut production and export. Twenty potential markets were evaluated on the basis of 11 criteria, and feasible alternatives were categorized into four classes. The study revealed that the USA, India, the United Kingdom and Japan were in the category of markets with the greatest potential for increasing exports (Dimension 1). Originality/value: This study has developed a novel approach that allows the comparison of the current market situation with potential market outcomes and creates an accurate classification of target markets
Influence of Past Climate Changes on the Current Distribution of a Rare and Endemic Species: Anatolian Spiny Mouse
Full text linkThis research focuses on species distribution modelling (SDM) to have an idea of distri- bution of Anatolian spiny mouse, Acomys cilicicus in the Last Glacial Maximum (LGM), the mid-Holocene and present by using coordinates along Silifke which is the only location the species found. Three ensembled species distribution models (generalized additive mod- els, maximum entropy and boosted regression trees) were used to project Anatolian spiny mouse environmental suitability. Results indicate that current distribution of A. cilicicus populations shifted east to west since during the Last Glacial Maximum and apparently eastern part of the Mediterranean region of Turkey is potential refugia for this species
On Quaternion-gaussian Fibonacci Polynomials
No full textIn this paper, we define Gaussian Fibonacci quaternion polynomials and Gaussian Lucas quaternion polynomials. We also investigate some properties of these quaternion polynomials
II. Meşrutiyet Döneminde Siyasal Uzlaşma Çabalarına Bir Örnek: Heyet-i Müttefika-i Osmaniye
Full text link1908 Temmuz’unda Meşrutiyet’in yeniden ilan edilmesi ile başlayan hürriyet ortamı, siyasal iklimin yeni bir veçheye bürünmesini beraberinde getirdi. Yeni cemiyet ve fırkaların tezahür etmesi ve yeni gazetelerin neşredilmesi bunun açık bir göstergesiydi. Böylece siyasal ortam bir önceki dönemle kıyaslanamayacak ölçüde canlandı. Bu da farklı anlayışlara sahip siyasi fırka ve cemiyetlerin kurulmasına ön ayak oldu. Ancak bu süreçte, Meşrutiyet’in iadesinde önemli bir rol oynayan ve iktidarı sahiplenen İttihâd ve Terakki Cemiyeti ile söz konusu fırka ve cemiyetler arasında yaşanan siyasi rekabet kısa sürede bir kutuplaşmaya dönüştü. Basının da körüklemesiyle giderek artan aşırı siyasallaşma, çeşitli etkenlerin de bir araya gelmesiyle 31 Mart Vak’ası’na yol açtı. Ülke bir anda rejim ve beka sorunuyla karşı karşıya kaldı. Böyle bir ortamda Meşrutiyet’in korunması ve ülke güvenliğinin yeniden sağlanması için fırka ve cemiyetler basının da desteğiyle “Heyet-i Müttefika-i Osmaniye” adıyla siyasal uzlaşmayı hedef alan bir kurul oluşturdular. Bu çalışmada “Heyet-i Müttefika-i Osmaniye”nin kuruluş süreci, hedefleri, çalışmaları ve bu sürecin nasıl sonuçlandığı üzerinde duruldu. Çalışmada döneme şahitlik eden gazeteler ve hatıratlar ile araştırma eserlerinden yararlanıldı
Pd nanoparticles decorated on Schiff base-modified chitosan/CeO2 as a heterogeneous and retriable nanocatalyst for Heck reactions and remediation of environmental pollutants
No full textIn this paper, we have developed a novel, highly active, eco-friendly, and versatile heterogeneous catalyst system in which Pd nanoparticles are decorated on Schiff base-modified chitosan‑cerium oxide particles (Pd@CS-CeO2). In order to confirm the successful fabrication of Pd@CS-CeO2, FTIR, XRD, SEM, TEM, BET, TG/DTG, and EDS analyses were performed, and its performance was evaluated as a heterogeneous nanocatalyst in Heck coupling reaction and reduction of nitro compounds. The catalytic tests showed that the desired Heck products were readily produced by Pd@CS-CeO2 without being contaminated with the aryl iodides, bromides, and chlorides. Moreover, different nitro compounds were efficiently reduced to corresponding amino compounds by Pd@CS-CeO2 within 95–160 s. Thanks to the heterogeneous nature of Pd@CS-CeO2 catalyst, it was easily recovered via simple filtration and reused up to 5 successive runs by giving 88 % yield. Due to its good catalytic and reusability performance together with stability/durability, Pd@CS-CeO2 is promising candidate as a catalyst for various catalytic or organic reactions
Does green investments improve air quality? Evidence for developed and developing European countries
No full textThe aim of this study is to examine the effect of green investments on air quality for developed and developing European countries. In this context, the short- and long-term effects of green investments on air quality were examined by panel generalized method of moments (GMM) and panel causality method. As a result of the GMM analysis, it has been determined that green investments negatively affect the air quality for both developed European countries and developing European countries in the short term, but this effect turns positive in developed countries in the long term. As a result of the panel causality analysis, two-way causality was determined between air quality and green investments
A due diligence on A1 level in terms of vocabulary in teaching Turkish to foreigners
No full textKelime hazinesi, bireyin dili iletişimsel olarak farklı sosyal bağlamlarda kullanmasının en önemli unsurlarından biridir. Kelime hazinesi gelişmemiş bireyler dile bağlı etkinliklerin tümünde çeşitli problemler yaşar. Bu sebeple temel düzeyde öğrencilerin bildiği ve kullandığı kelimeleri belirlemek gerektiği takdirde bunları geliştirecek ve çeşitlendirecek etkinlikler düzenlemek dil becerilerinin gelişimi açısından hayati bir öneme sahiptir. Buna bağlı olarak bu araştırmada A1 seviyesinde eğitim görmekte olan uluslararası öğrencilerin çevremiz ünitesindeki kelime hazinelerini belirlemek ve ilgili ünitedeki metinlerin kelime hazinesi katsayıları ile karşılaştırmak amaçlanmıştır. Araştırmada nitel araştırma desenlerinden temel nitel desen kullanılmıştır. Araştırmanın çalışma grubunu İstanbul’da bir devlet üniversitesine bağlı TÖMER’de eğitim gören 32 öğrenci oluşturmaktadır. Araştırmanın inceleme nesnelerini, Yedi İklim Yabancılar İçin Türkçe Öğretim Seti A1 kitabının “Çevremiz” ünitesinde yer alan metinler ile çalışma grubundaki öğrencilerin devam ettiği A1 kurunun 4. haftasının sonunda gerçekleştirilen iki farklı yazma uygulamasında toplanan veriler oluşturmaktadır. Araştırmada veriler doküman incelemesi ile toplanmıştır. Elde edilen veriler Microsoft Word programına aktarılmış “Simple Concordance Program 4.07” programıyla kelime sıklığı katsayısı, her öğrenci için kelime hazinesi katsayıları, genel kelime hazinesi sıklık analizleri gerçekleştirilmiştir. Kelime listelerin hazırlanmasından sonra elde edilen veriler betimsel olarak analiz edilmiştir. İnceleme sonucunda birinci uygulamada kelime hazinesi katsayısı 0.19; ikinci yazma uygulamasında 0.16; genel kelime hazinesi katsayısı 0.13 olarak belirlenmiştir. Ayrıca ünitede yer alan metinler ile öğrencilerin yazılı anlatım uygulamaları karşılaştırıldığında birinci yazma çalışmasında öğrencilerin %48’i ilgili metnin kelime hazinesi katsayısının altında kalırken ikinci yazma çalışmasında öğrencilerin % 16’sı kelime hazinesi katsayısının altında kalmıştır. İncelenen metinlerde kalıp söz, ikileme ve deyimlere ise rastlanamamıştır.Vocabulary is one of the most important elements of an individual's use of language communicatively in different social contexts. Individuals whose vocabulary is not developed experience various problems in all language-related activities. For this reason, if it is necessary to determine the words that students know and use at the basic level, it is of vital importance for the development of language skills to organize activities that will develop and diversify them. Accordingly, in this study, it is aimed to determine the vocabulary of international students studying at A1 level in our environment unit and to compare them with the vocabulary coefficients of the texts in the relevant unit. In the study, basic qualitative design was used from qualitative research designs. The study group of the study consists of 32 students studying at TOMER, a state university in Istanbul. The study objects of the research are the texts in the "Our Environment" unit of the Seven Climates Turkish Teaching Set for Foreigners A1 book and the data collected in two different writing practices carried out at the end of the 4th week of the A1 course attended by the students in the study group. In the study, data were collected by document review. The obtained data were transferred to the Microsoft Word program and word frequency coefficient, vocabulary coefficients for each student, general vocabulary frequency analyzes were performed with the "Simple Concordance Program 4.07" program. The data obtained after the preparation of the word lists were analyzed descriptively. As a result of the examination, the vocabulary coefficient in the first application was 0.19; 0.16 in the second writing application; the general vocabulary coefficient was determined as 0.13. In addition, when the texts in the unit and the written expression practices of the students were compared, 48% of the students in the first writing study were below the vocabulary coefficient of the relevant text, while in the second writing study, 16% of the students were below the vocabulary coefficient. In the texts examined, phrases, dilemmas and idioms were not found
The diurnal change of thyroid-stimulating hormone and the effect of this change on thyroid functions in patients with chronic kidney disease
No full textThyroid-stimulating hormone (TSH) has a pulsatile and circadian rhythm in healthy individuals. We aimed to evaluate the diurnal changes of free thyroid hormones and serum TSH levels in patients with end-stage renal failure (ESRF) whose thyroidal functions are at normal ranges. Methods: Thirty hemodialysis patients with chronic renal failure and without a known thyroidal disease who are over 18 and 35 healthy individuals were included. The serum TSH, free T3, and free T4 levels were examined among the patient and control group which were taken at 8:00 a.m., 4:00 p.m., and 0:00 a.m. Results: Twenty-two (73.3%) patients were male, and the mean age of the patient group was 64 (sd = 14.45 years). Seventeen (48.6%) of the control group were female, and the mean age was 31.9 (sd = 6.4 years). Serum free T3 levels, measured at three different time points (8:00 a.m., 4:00 p.m., and 0:00 a.m.), were significantly lower in the patient group than in the control group and serum free T4 levels were measured at three different time points (8:00 am, 4:00 p.m., and 0:00 a.m.) were significantly higher in the patient group than in the control group. Serum TSH levels were higher in the patient group than in the control group at 08:00, and were lower at 24:00 (p < 0.001). The nocturnal increase of serum TSH level under 0.525 suggested diurnal rhythm disruption with 83% sensitivity and 87% specificity. Conclusion: The nocturnal serum TSH increase is not seen in ESRF patients who did not have a thyroid disease. We think that not observing a nocturnal TSH increase could be an early indication of the sick euthyroid syndrome