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The effect of 8 weeks of pliometri?k studies applied to kick boxing athletes on balance, reaction time and agility
Get PDFBu çalışmanın amacı, 10-13 yaş arasındaki lisanslı erkek kickboks sporcularında 8 hafta süre ile yapılan pliometrik çalışmaların, denge, reaksiyon zamanı ve çeviklik özelliklerine olan etkileri araştırmaktır. Araştırmaya, İstanbul ili Pendik ilçesinde faaliyet gösteren Pendik Prestij Spor Savunma Sporları Kulübündeki lisanslı 32 erkek sporcu gönüllü katılmıştır. Rastgele dağılım yöntemiyle sporcular, çalışma ve kontrol grubu olarak 2 gruba ayrılmıştır. Çalışma grubuna, haftada 3 gün 60 dk şeklinde yaptıkları kickboks antrenmanı öncesinde 30 dk pliometrik çalışma yaptırılmıştır. Kontrol grubuna ise sadece haftada 3 gün 60 dakikalık kickboks antrenmanları yaptırılmıştır. Kontrol grubuna bunun dışında farklı bir uygulama yaptırılmamıştır. Her iki gruba da ön test-son test olacak şekilde; denge, reaksiyon zamanı ve çeviklik testleri uygulanmıştır. Verilerin analizi, SPSS 25 Paket programında yapılmıştır. Verilerin normal dağılıp dağılmadığını öğrenmek için Skewness-Kurtosis, histogram ve q-q plot değerlerine bakılmıştır. Kontrol ve çalışma grubuna öntest-sontest farkları için kendi içerisinde eşleştirilmiş örneklem t testi yapılmıştır. Gruplar arası farklar için Bağımsız Örneklem T testi yapılmıştır. Anlamlılık değeri, başlangıçta p<0.05 olarak kabul edilmiştir. Yapılan analizler sonucunda, çalışma grubundaki sporculara uygulanan 8 haftalık pliometrik çalışmaların, reaksiyon zamanı, denge ve çeviklik değerleri üzerinde olumlu etkiye sahip olduğu tespit edilmiştir. Kontrol grubundaki sporcularda da reaksiyon zamanı ve çeviklik değerlerinin son testlerde öntestlere nazaran daha iyi olduğu görülmüştür. İki grup arasındaki son test farkları incelendiğinde ise çalışma grubunun, kontrol grubuna göre reaksiyon zamanı ve çeviklik değerlerinde, istatistiksel olarak daha anlamlı ve iyi sonuçlar olduğu tespit edilmiştir. Bu sebeple antrenörlere, 10-13 yaş aralığındaki erkek kickboks sporcularında, antrenmanlara ek olarak pliometrik çalışmaların da antrenman programlarına eklenmesinin ve yaptırılmasının faydalı olabileceği söylenebilir. Ayrıca bu alanda yeni çalışmalar yapacak olanlara, el-göz-ayak şeklinde üçlü koordinasyon da içeren ölçüm testlerini yapmaları önerilebilir. Anahtar kelimeler: Çeviklik, Denge, Kickboks, Pliometrik, Reaksiyon zamanı.The aim of this study was to investigate the effects of plyometric training for 8 weeks on balance, reaction time and agility in licensed male kickboxing athletes aged 10-13 years. In the study, 32 licensed male athletes from Pendik Prestij Sports Defense Sports Club, which operates in Pendik district of Istanbul province, participated voluntarily. The athletes were divided into 2 groups as study and control group by random distribution method. The study group was given 30 minutes of plyometric training before kickboxing training for 60 minutes 3 days a week. The control group only had kickboxing training for 60 minutes 3 days a week. The control group did not have any other application. Balance, reaction time and agility tests were applied to both groups as pre-test and post-test. The analysis of the data was done in SPSS 25 Package program. Skewness-Kurtosis, histogram and q-q plot values were analyzed to find out whether the data were normally distributed. Paired sample t-test was performed within the control and study groups for pretest-posttest differences. Independent Sample T test was performed for differences between groups. The significance value was initially accepted as p<0.05. As a result of the analysis, it was determined that 8-week plyometric exercises applied to the athletes in the study group had a positive effect on reaction time, balance and agility values. Reaction time and agility values of the athletes in the control group were also found to be better in the post-tests compared to the pre-tests. When the post-test differences between the two groups were analyzed, it was determined that the study group had statistically more significant and better results in reaction time and agility values than the control group. For this reason, it can be said that it may be useful for coaches to add plyometric exercises to the training programs in addition to the training programs of male kickboxing athletes between the ages of 10-13. In addition, those who will conduct new studies in this field may be recommended to perform measurement tests including hand-eye-foot triple coordination. Keywords: Agility, Balance, Kickboxing, Pliometriks, Reaction time
Numerical analysis of a poroelastic cartilage model: Investigating the influence of changing material properties in osteoarthritis
Get PDFSeveral changes occur in both the cartilage's material properties and anatomical structure as osteoarthritis progresses. Unlike most numerical studies that solely consider individual changes, our study aimed to understand the impact on cartilage mechanics by considering the combined effect of material properties and cartilage thickness varied with osteoarthritis progression. In total, 3 three-dimensional finite element models, representing the intact, early, and late osteoarthritis conditions, were developed to simulate a load-bearing area in the knee. The articular cartilage was modelled as fluid-saturated linear biphasic poroelastic to incorporate solid-fluid interaction. All models underwent prolonged creep (50 N) and relaxation (0.3 mm) analyses for 600 s. In the early stage of osteoarthritis, the tibial cartilage demonstrated an overall stiffer behaviour attributed to cartilage swelling despite decreased stiffness at the material level. On the other hand, in the late stage of osteoarthritis, the decrease in cartilage thickness led to increased knee deformation. Additionally, increased permeability resulted in accelerated fluid exudation across all osteoarthritis models, and the elevation in void ratio further intensified fluid pressure within the cartilage to a higher magnitude. Furthermore, these changes collectively influenced both the magnitude and distribution of the outcomes. A holistic understanding of the material properties altered in osteoarthritis may contribute to a better understanding of the mechanical performance of cartilage during disease progression.Scientific and Technological Research Council of TURKEY (TUBITAK)The authors disclosed receipt of the following financial support for the research, authorship, and/or publication of this article: Sabri UZUNER is awarded a grant by The Scientific and Technological Research Council of TURKEY (TUBITAK) to visit the University of Calgary (CANADA)
Beam deflection coupled systems of fractional differential equations: existence of solutions, Ulam-Hyers stability and travelling waves
Get PDFIn this paper, we study a coupled system of beam deflection type that involves nonlinear equations with sequential Caputo fractional derivatives. Under flexible/fixed end-conditions, two main theorems on the existence and uniqueness of solutions are proved by using two fixed point theorems. Some examples are discussed to illustrate the applications of the existence and uniqueness of solution results. Another main result on the Ulam-Hyers stability of solutions for the introduced system is also discussed. Some examples of stability are discussed. New travelling wave solutions are obtained for another conformable coupled system of beam type that has a connection with the first considered system. A conclusion follows at the end.Duzce UniversityThe authors would like to express their sincere thanks to the editor and the anonymous reviewers for their helpful comments and suggestions. Thanks to Professor M. Benbachir for his proposition regarding the subject of Fractional Differential Equations of you
Bireysel ve Sosyal Faktörlerin Madde Bağımlılığı Şiddeti Üzerindeki Yordayıcı Etkilerinin Karşılaştırılması
Get PDFAmaç: Bu çalışma, madde bağımlılığının önlenmesinde bireysel ve sosyal faktörlerin etkilerini inceleyerek, bu süreçte koruyucu bir rol oynayan faktörleri belirlemeyi amaçlamaktadır. Özellikle, hangi faktörlerin daha etkili olduğunu belirlemek amacıyla yapılan değerlendirmeye odaklanılmıştır. Yöntem: Araştırmaya dahil edilen 18-65 yaş aralığında 101 erkek katılımcıya, “Kişisel Sosyodemografik Bilgi Formu”, “Ailedeki Koruyucu Etkenler Ölçeği”, “Çok Boyutlu Algılanan Sosyal Destek Ölçeği”, “Kısa Psikolojik Sağlamlık Ölçeği”, “Başa Çıkma Stilleri Ölçeği Kısa Formu”, “Kısa Öz Kontrol Ölçeği”, “Bağımlılık Profil İndeksi Kısa Formu” ve “Duygu Düzenleme Ölçeği” anketleri uygulanmıştır. Bulgular: Algılanan sosyal arkadaş desteği, dürtüsellik, duygulara odaklanma ve ortaya koyma, bağımlılık şiddetini en iyi şekilde açıklayan koruyucu faktörler oldukları saptanmıştır. Ayrıca sosyal koruyucu faktörlerin, bireysel koruyucu faktörlere göre madde bağımlılığını açıklama gücü daha yüksek olduğu saptanmıştır. Sonuç: Madde bağımlılığıyla mücadele stratejileri geliştirilirken bireylerin sosyal destek sistemlerini güçlendirmeye, duygusal düzenleme becerilerini artırmaya ve dürtüselliği azaltmaya odaklanmak etkili olabilir. Ayrıca, bu çalışmanın sonuçları, bağımlılıkla mücadelede geniş bir perspektifin önemini vurgulayarak, bireysel ve sosyal faktörler arasındaki etkileşimleri anlamak için daha fazla araştırmaya ihtiyaç olduğunu göstermektedir
Review and Design of a Simple 60 GHz Microstrip Antenna for Enhanced 5G Performance
Get PDFThe emergence of 5G technology has drawn the attention of researchers to the 60 GHz frequency spectrum which provides a wide bandwidth and massive data transfer with high data rates and low latency communication. Wireless systems utilizing 60 GHz enable multiantenna systems and several applications on the contrary to lower carrier frequencies. In this study, the prominence of the 60 GHz frequency is explained with references to various studies, information from web pages, and publications. While offering faster data transfer compared to 4G and Wi-Fi signals, unfortunately, it has a shorter range. The effectiveness of 60 GHz is only applicable for unobstructed distances; the range decreases significantly in the presence of obstacles. Attenuation is another important issue, because of the oxygen at 60 GHz frequency, most of the signal is absorbed, so it is thought that it will be preferred more for indoor applications and wireless office communication. Technologic progresses continue rapidly, perhaps by increasing the number of sectors of base stations, beam forming technology or mesh networking between electronic devices the long distance issue can also be eliminated. In this study, an antenna design was also given after the review of 60 GHz and 5G, as a research side and it had -8.7 dB S11 value and 5.54 dBi gain. The designed micro strip antenna, particularly at 60 GHz, holds significant potential for various applications and contributes to the advancement of future communication technologies. Some potential applications include: 5G, wireless local area networks, indoor wireless communications, short range communication links, point-to-point and point-tomultipoint links, IoT, advancement in mm wave technology and so on with high data rate
Durability Ratings of Post-treated Wood-based Composites after 14 Years of Field Exposure
Get PDFSeveral commercial wood -based composites (softwood plywood [SWP], hardwood plywood [HWP], medium -density fiberboard [MDF], oriented strand board [OSB], and particleboard) [PB]) were post -treated with alkaline copper quat and copper azole at two different retention levels. The treated specimens were installed on concrete blocks covered with 5 -sided PVC boxes simulating the crawl space conditions (protected aboveground) in Japanese houses in Southern Japan where decay and termite activity are high. The experimental variables are a comparison of treated versus untreated, preservative type and retention levels. During 14 years of exposure, the specimens were biannually visually rated. In general, termite damage became visible earlier and the harshness of attack was higher when compared to decay damage. The untreated and treated MDFs were the most resistant under the protected above ground conditions at the end of 14 years exposure. Particleboard durability performance followed the MDF rating during the same period. The untreated OSB, HWP, and SWP were the least resistant composite types. The treatments substantially increased the durability of the mentioned composite types by 317.6%, 80.5%, and 133% higher termite grading when correlated to their untreated controls, respectfully, yet they failed to maintain full protection. Based on statistical analysis, preservative types and retention levels did not significantly affect decay and termite ratings.RISH, Kyoto UniversityThe first author extends his appreciation to RISH, Kyoto University for support under the Visiting Professor program between 1St March 2023 to 31St August 2023, and to Mr. Akio Adachi and the Laboratory of Innovative Humano-habitability personnel who were involved in 14 years of data collection
Institutions and macroeconomic indicators: entrepreneurial activities across the world
Get PDFPurposeEntrepreneurial activity is a phenomenon that increases the economic growth of countries and improves their social welfare. The economic development levels of countries have significant effects on these entrepreneurial activities. This research examines which institutional and macroeconomic variables explain early-stage entrepreneurship activities in developed and developing economies.Design/methodology/approachThe authors conducted panel data analysis on the data from the Global Entrepreneurship Monitor (GEM) and International Monetary Fund (IMF) surveys covering the years 2009-2018.FindingsFirst, the authors' results reveal that cognitive, normative and regulatory institutions and macroeconomic factors affect early-stage entrepreneurial activity in developed and developing countries differently. Second, the authors' findings indicate that cognitive, normative and regulatory institutions affect early-stage entrepreneurship more positively in developed than developing countries. Finally, the authors' results report that macroeconomic factors are more effective in early-stage entrepreneurial activity in developing countries than in developed countries.Originality/valueThis study provides a better understanding of the components that help explain the differences in entrepreneurship between developed and developing countries regarding institutions and macroeconomic factors. In this way, it contributes to developing entrepreneurship literature with the theoretical achievements of combining institutional theory and macroeconomic indicators with entrepreneurship literature
In Vivo Genotoxicity Testing of Bentazone Herbicide in Danio rerio Erythrocytes Using the Micronucleus and Nuclear Abnormality Assays
Get PDFBentazone herbicide is in the benzothiadiazole group and is often used for the elimination of weeds. In this experiment, the in vivo genotoxicity of bentazone herbicide in Danio rerio erythrocytes was investigated using micronucleus and nuclear abnormality assays. Fish were exposed to three different concentrations (2.5, 5, and 10 mg/L) for 24, 48, 72, and 96 h, including the control group. When compared with the negative group, it was found that there was a statistical increase in the number of micronuclei in a concentration-dependent manner. According to the data obtained from the erythrocyte nucleolar abnormality assay, the most common abnormality for the 24-h treatment was kidney-shaped nucleus (at 10 mg/L concentration); the most common abnormality for the 48-, 72-, and 96-h treatment periods was echinocyte (at 5 and 10 mg/L concentrations). All concentrations of bentazone herbicide caused an increase in the total abnormality level in Danio rerio erythrocytes at all treatment times. These increases were concentration dependent for 24-, 72-, and 96-h treatment times, except for the 48-h treatment. Furthermore, for all treatment groups, the high concentration of bentazone herbicide (10 mg/L) caused changes on the long-short axis of the erythrocytes and the long-short axis of the nucleus, but these changes were not statistically significant. The data we obtained as a result of the study showed that bentazone herbicide is genotoxic for aquatic organisms depending on their use. Further research into different aquatic organisms is needed to investigate the genotoxicity mechanisms of bentazone herbicide in aquatic organisms
2022 Düzce, Türkiye earthquake: advances in the past 2 decades, lessons learned, and future projections
Get PDFIn the year 1999, two devastating earthquakes (Mw 7.4 Kocaeli earthquake in August and Mw 7.2 D & uuml;zce earthquake in November) occurred in Northwest T & uuml;rkiye. These two earthquakes led to a very large number of casualties and building collapses. When the 1999 earthquakes occurred, most of the structures in the earthquake-impacted region were not designed according to modern seismic design codes. During the 25 years following those earthquakes, there have been significant advances in building construction in the light of earthquake engineering, including adequate seismic codes, new regulations, and effective code enforcement in the earthquake impacted region. These advances have been reflected in the construction of new structures in the region and the retrofitting of existing ones. As a result, 70-80% of the current building stock in D & uuml;zce was designed, constructed, or retrofitted after the 1999 earthquakes. Almost 23 years later, in 2022, an Mw 6.1 earthquake occurred in D & uuml;zce, with ground shaking close to the seismic design code life safety performance level. The 2022 earthquake provided a great opportunity to evaluate the effectiveness and consequences of the advances in earthquake engineering and the relevant policy-making and regulations. This paper provides a comparative overview of the 1999 and 2022 earthquakes that struck the city of D & uuml;zce in terms of hazard, vulnerability, and consequences. Furthermore, other key lessons learned from the 2022 D & uuml;zce earthquake are documented based on field reconnaissance and numerical simulations. The lessons learned are expected to provide useful guidance for the reconstruction efforts after the 2023 Kahramanmara & scedil; T & uuml;rkiye earthquake sequence or in similar efforts in other parts of the world.Scientific and Technological Research Council of Tuerkiye (TUEBIdot;TAK)Open access funding provided by the Scientific and Technological Research Council of Tuerkiye (TUEB & Idot;TAK). The authors declare that no funds, grants, or other support were received during the preparation of this manuscript DAS:The datasets generated during and/or analyzed during the current study are available from the corresponding author on reasonable request
A study on error bounds for Newton-type inequalities in conformable fractional integrals
Get PDFThe authors of the paper suggest a novel approach in order to examine an integral equality using conformable fractional operators. By using this identity, some Newton-type inequalities are proved for differentiable convex functions by taking the modulus of the newly established equality. Moreover, we prove some Newton-type inequalities by using the H & ouml;lder and power-mean inequality. Furthermore, some new results are presented by using special choices of obtained inequalities. Finally, we give some conformable fractional Newton-type inequalities for functions of bounded variation