Do the effects of vitamin d supplementation on muscle strength differ according to age?

Introduction: Vitamin D plays an important role in musculoskeletal health and its use improves muscle strength. However, the effect of vitamin D use on muscle strength in women of different ages is yet to be investigated. Therefore, in this study, we aimed to evaluate the effect of vitamin D use on muscle strength in women of different age groups and determine the differences of muscle strength gain between age groups. Materials and Method: Sixty-three women with calcidiol levels<30 ng/mL were randomly assigned and stratified by their age group as follows: Group I (aged 40–49 years), Group II (aged 50–59 years) and Group III (aged 60–69 years). Calcidiol levels, body mass index, fat free mass, percent fat, grip strength, arm curl, chair stand and isokinetic concentric flexor and extensor peak torque and power at 60°•s−1 and 180°•s−1 were assessed at baseline and six months after oral cholecalciferol supplementation. Results: Vitamin D supplementation caused significant improvement in body mass index, arm curl, grip strength and knee flexor and extensor peak torque and power at 60°•s−1 and 180°•s−1 in all groups (p<0.05). Knee flexor power at 60°•s−1 and extensor power at 180°•s−1 were significantly higher in group I than in group III (p<0.025). Conclusion: Muscle strength in response to vitamin D supplementation increased in all age groups, and isokinetic muscle power was the highest in the youngest age group studied. © 2018, Geriatrics Society. All rights reserved

Antioxidative and proline potentials as a protective mechanism in soybean plants under salinity stress

Stress can define as all negative factors affecting plant growth. One of the most important problems among stress factors is salt stress. Antioxidant responses are tested in Soybean (Glycine max. L.) cv., “A3935” grown under 0, 50, 100 and 150 mM NaCl in order to investigate the plants protective mechanisms against salt induced oxidative stress. The NaCl treatments are repeated in four different stages of that is 10, 20 and 30 days after sowing (DAS). The plants were uprooted randomly on 30 DAS and the enzymatic antioxidant potentials were analyzed. The fresh and dry weights and the chlorophyll content are reduced with increasing NaCl concentration. Proline concentration increased at high salinity compared to untreated plants. Moreover, salinity induces a significant decline in superoxide dismutase (SOD, EC 1.15.1.1), glutathione reductase (GR, EC 1.6.4.2), ascorbate peroxidase (APX, EC 1.11.1.11) and catalase (CAT, EC 1.11.1.6) activities may be of great importance in H2O2 intoxicating mechanism under oxidative stress. As expected Na+ and Cl- concentrations in leaf and roots are higher at high salinity treatments compared to untreated plants. The concentrations of K+ are reduced with increasing NaCl concentrations.Key words: Antioxidants, antioxidant enzyme, salinity, soybean, proline

Çelik Çerçevelerin LRFD-AISC Şartnamesine Göre Av Arama Optimizasyon Yöntemi Kullanılarak Optimum Boyutlandırılması

Konferans Bildirisi -- Teorik ve Uygulamalı Mekanik Türk Milli Komitesi, 2013Conference Paper -- Theoretical and Applied Mechanical Turkish National Committee, 2013Bu çalışmada çelik çerçeveler için av arama optimizasyon yöntemini temel alan bir optimum tasarım algoritması sunulmaktadır. Aslan, kurt ve yunus gibi hayvanların gurup olarak avlanmalarından esinlenilerek geliştirilmiş olan av arama optimizasyon yöntemi de bu tekniklerin son dönemlerde ön plana çıkanlarından biridir. Bu avcılarıjn her biri avlanmalarını farklı şekillerde gerçekleştirir. Fakat ortak yönleri grup içinde birlikte av aramalarıdır. Avın etrafı çembere alınır ve yakalanana kadar çember daraltılır. Mevcut çalışmada av arama tekniği çerçeve optimizasyon algoritmasının otomasyonu için kullanılmıştır. İki boyutlu çelik çerçevelerin optimum tasarımının gereği olarak; yapı elemanlarının W profiline uygun olması, LRFD-AISC tasarım şartnamelerindeki sınırlayıcıları sağlaması ve çerçevenin minimum ağırlığa sahip olması gerekmektedir. Bu amaçla burkulmayı da hesaba katan dayanım sınırlayıcıları göz önünde bulundurulmuş ve algoritmanın kolon ve kirişler için Amerikan Şartnamesindeki 272 kesit içerisinden seçim yapması sağlanmıştır. Her bir grup içindeki elemanlara aynı kesitin tayin edilebilmesi için eleman gruplandırılması yapılmıştır. Şartnamedeki sınırlayıcıları dikkate alarak minimum çerçeve ağırlığını hesaplayan bu algoritmanın etkinliği örnek problemlerle gösterilmiştir.This study presents a hunting search based optimum design algorithm for moment resisting steel frames. Hunting search algorithm is a numerical optimization method inspired by group hunting of animals such as wolves, lions, and dolphins. Each of these hunters performs hunting in a different way. However, they are common in that all of them look for a prey in a group. Prey is encircled and the ring of siege is tightened gradually until it is caught. Hunting search is employed for the automation of optimum design process, during which size variables are selected from an available W-steel section list in such a way that the weight of frame is minimum and the design constraints are satisfied. Provisions of LRFD-AISC (Load and Resistant Factor Design-American Institute of Steel Construction) are considered to formulate the optimum design problem. Different numerical examples are designed by the presented algorithm to demonstrate its efficiency. Results reveal that hunting search shows good performance in finding optimum solutions for moment resisting steel frames

INVESTIGATING THE SPATIAL REASONING SKILLS OF STUDENTS IN THE CONTEXT OF MATHEMATICAL THINKING PROFILES

The aim of this study was to examine whether there is a relationship between the spatial reasoning skills and mathematical thinking profiles of elementary school students. The quantitative method of descriptive survey model was used in the study. The sample of the study comprised 103 fourth grade elementary school students in Turkey. The Mathematical Process Test and Spatial Reasoning Test, which are valid and reliable, were used as data collection tools. According to the answers given by the students to the Mathematical Process test, it was decided based on the upper and lower limits of each group determined beforehand that the students had a thinking profile. Scores were also collected from the Spatial Reasoning Test. MANOVA test was performed to examine whether the spatial reasoning skills differed from the mathematical thinking profiles of the students. The results revealed that students with a visual thinking profile were more successful in both the Mathematical Process Test and the Spatial Reasoning Test.  Article visualizations

İnce Kirişlerin Elastik Davranışlarının NIY ve RNIY Yöntemleri İle İncelemesi

Konferans Bildirisi -- Teorik ve Uygulamalı Mekanik Türk Milli Komitesi, 2013Conference Paper -- Theoretical and Applied Mechanical Turkish National Committee, 2013Bu çalışmada, ince kirişlerin elastik davranışlarının incelenmesi, ağsız yöntemlerden olan Noktasal İnterpolasyon (NİY) ve Radyal Noktasal İnterpolasyon (RNİY) yöntemleri ile gerçekleştirilmiştir. Her bir yöntemde, iki farklı integrasyon tekniği kullanılmıştır. Standard olarak kullanılan Gauss integrasyon tekniği, Taylor noktasal integrasyon tekniği ile karşılaştırılmış, NİY ve RNİY üzerine etkileri araştırılmıştır. Noktasal direngenlik matrisinin elde edilmesi, Bernoulli-Euler kiriş teorisine göre gerçekleştirilmiştir. Farklı etki alanı büyüklükleri ve farklı RNİY şekil parametrelerinin çözümler üzerine etkileri ayrıca ele alınmıştır. Bir ankastre kiriş problemi, serbest uca tekil yük uygulanarak çözülmüştür. Elde edilen çözümler, ANSYS paket programı kullanılarak sonlu elemanlar yöntemiyle kıyaslanmıştır.In this study, the point interpolation method (PIM) and radial point interpolation method (RPIM) solutions of elastic thin beams are compared by using standard Gaussian integration and a nodal integration based on Taylor series expansion. The effects of integration schemes, support domain sizes and RPIM shape parameters on the convergency are also investigated. Nodal stiffness matrices are obtained using Bernoulli-Euler beam theory. A cantilever beam problem with concentrated load applied on one end is solved and the results are compared with finite element solutions in ANSYS

Development of Upper Euphrates Basin hydro-economic model and hydropower generation optimization

Hydro-economic optimization models are common in hydropower reservoir modeling to aid system operators and planners. In these models, operations are driven by the economic value and constrained by the availability of water. The objective is to either minimize total costs or maximize total benefits. In this study, a hydro-economic optimization model for the integrated reservoir system of the Upper Euphrate s Basin, with major tributaries providing water flow to the Euphrates River, is introduced. These model the 10 large-scale reservoirs of the basin with a total installed capacity of 3,255 MW. Water management and hydropower decision-making operations are evaluated with a piecewise linear programming algorithm in monthly time steps using a 45-year historical hydrology between 1971 and 2016. The model aims to maximize hydropower revenue over a long-term time horizon with energy prices varying by month. Reservoir storage and turbine release decisions are optimized for multiple hydropower plants connected in serial or parallel. Hydropower generation, revenue, reservoir storage, capacity ratios and generation reliability results are analyzed. Results show that these hydropower plants generate about 9,481 Gigawatt hour (GWh) of energy with an average turbine capacit y use of 36% and obtain a revenue of 620 million $ per year

Experimental investigation of thermal comfort performance of a radiant wall and ceiling panel system

The number of radiant heating-cooling systems in building applications is increasing it is because of low energy consumption, low operating temperature and high values they provide in terms of working compatibility with renewable energy sources. In this study, ground source heat pump integrated radiant panels installed on the wall and suspended ceiling of the office room in Yıldız Technical University Science and Technology Application and Research Centre were experimentally examined in terms of thermal comfort according to the relevant standards. Vertical air temperature differences and mean radiant temperatures were investigated. The mean air temperature differences at 0.1 m and 1.7 m were found to be 3,9 oC 2.9 oC 3.5 oC, 3.1 oC and 3.4 oC on average for the five different stands, respectively. PMV and PPD values were found to be 0.78 and 18.9% for February 12 (Case 1), 0.36 and 8.4% for February 13 (Case 2), respectively. In the experiment carried out under the conditions of Case 2, while the comfort conditions were provided in almost all of the day, the desired comfort conditions could not be achieved in Case 1 after 11 am. © 2022. All Rights Reserved.Yildiz Teknik Üniversitesi: FBA-2019-3703This study was supported by Yıldız Technical University under BAP program with GRANT No. FBA-2019-3703. We would like to thank to the Yıldız Technical University for their financial support during this work