DOĞU KAYINI (Fagus oriantalis L.) ve KARA KAVAK (Populus nigra L.) KOMBİNASYONU İLE ÜRETİLMİŞ LAMİNE AĞAÇ MALZEMELERİN BAZI FİZİKSEL ve MEKANİK ÖZELLİKLERİ

Bu çalışma, Doğu kayını ve Kara kavak kombinasyonu ile üretilmiş lamine ağaç malzemelerin bazı fiziksel ve mekanik özelliklerinin belirlenmesi amacıyla yapılmıştır. Bu amaçla Doğu kayını ve Kara kavak odunlarından PVAc-D4 tipi tutkal ile beş katmanlı olarak hazırlanan lamine masif ağaç malzemeler kullanılmıştır. Hazırlanan 250 adet deney örneği üzerinde; yoğunluk TS 2472, eğilme direnci TS 2474, eğilmede elastiklik modülü TS 2478, basınç direnci TS 2595, makaslama direnci ASTM D 3110, yarılma direnci ise ASTM D 143 esaslarına uyularak belirlenmiştir. Deneyler sonunda, Doğu kayını ve Kara kavak kombinasyonu ile üretilmiş lamine ağaç malzemelerin hava kurusu yoğunluğu 0.571g/cm3, eğilme direnci 98.66 N/mm2, eğilmede elastiklik modülü 9020.24 N/mm2, basınç direnci 54.49 N/mm2, makaslama direnci 9.11 N/mm2, yarılma direnci 0.540 N/mm2 olarak bulunmuştur. Bu sonuçlara göre; kayın ve kavak kombinasyonu ile üretilmiş lamine ağaç malzemeler mobilya malzemesi olarak kullanılması önerilebilir. Anahtar kelimeler: Laminasyon, Doğu kayını, Kara kavak, PVAc-D4 Tutkal

Analysis of Patients Who Present to Emergency Departments During Ramadan

INTRODUCTION: Fasting is one of the five basic obligations of Islam. Muslims fast during the month of Ramadan according to the lunar calendar. Fasting during Ramadan involves abstinence from food and drinks from sunrise to sunset. The present study investigated the effect of fasting during Ramadan in patients who presented to emergency departments. Results of this study may guide healthcare authorities in countries that provide health services to Muslim communities because of increased migration. MATERIAL AND METHODS: This is the first prospective multicentre study to examine emergency department applications for Ramadan. The study was performed between 05.26.2017 and 06.24.2017. Patients were classified according to cardiopulmonary complaints, trauma-associated complaints, neurological complaints, gastrointestinal complaints, headache, renal colic, upper respiratory tract complaints, and malaise. Vital signs, age, gender, presentation type, complaint type, hospital stay duration, requested laboratory examination, radiological examination, treatment outcomes, application time, smoking status, and fasting status of the study patients were recorded by using a questionnaire. RESULTS: Fasting and non-fasting patients showed a significant difference with respect to presentation type, gastrointestinal complaints, upper respiratory tract complaints, hospitalization status, requested radiological and biochemical examinations, hospitalization duration, and application time (p < 0.05). CONCLUSIONS: To the authors’ knowledge, the present study is the first to compare the complaints of fasting and non-fasting patients during Ramadan. The authors feel that this study is superior to several previous studies because it has been performed using a different perspective and provides more accurate and objective data than those reported in previous studies

Determination of Some Physical Attributes for Wooden Construction Elements Strengthened with Woven Wire Fiberglass

This study designed composite wooden construction elements strengthened with woven wire fiberglass netting and determined the technical attributes. Scots pine (Pinus sylvestris L.) was used in wooden layers, and woven wire fiberglass netting was used in intermediate layers. Layers were pressed with polyvinyl acetate (PVAc) D3 and Desmodur-VTKA adhesives to form 7 solid 13-layer laminated composite specimens. Experiments on 95 specimens determined density, bonding strength, bending resistance, and compression strength; solid and solid laminated wooden materials were tested and compared. BS EN 204 and BS EN 205 standards were complied with for bonding strength tests, TS 5497 EN 408 was used for densities, and TS 549 EN 408 was followed for bending resistance and compressive strength. Most factors, except for intermediate layer material in compressive strength and bending resistance tests perpendicular to the glue line, did not cause significant differences. Variables (adhesive, intermediate layer material) used for determining bending strength parallel to the glue line were effective. Polyurethane adhesive increased resistance to bending parallel to the glue line. These composite wooden construction elements supported with woven wire fiberglass netting could be advantageous for applications that require high bending resistance perpendicular to the glue line. However, these composites do not hold a compressive strength advantage

Finite-element analyses of light timber-framed walls with and without openings

WOS: 000405421200003The static responses of timber-framed shear walls with and without openings of variable dimensions and locations were numerically investigated using the finite-element (FE) method. The lateral load resistance capacities and general load-displacement behaviours of the timber-framed shear walls were investigated. In the FE study, the frame elements were modelled as beams, plates were modelled as shells and nails were modelled as spring elements. The plastic behaviour of the materials was modelled using experimental stress-strain relationships of the materials. For timber frames and oriented strand board (OSB) panels, uniaxial stress-strain curves were experimentally obtained under tensile and compressive loading. From the experimental materials models it was found that spruce exhibited non-linear behaviour under both tensile and compressive stress. In contrast, the OSB sheathing layer used in the analyses exhibited non-linear behaviour under compressive stress and linear behaviour under tensile stress. The numerical results were verified using experimental load-deflection relationships obtained from a previous study. Good agreement was found between the analytical and experimental results. To further examine the applicability of the experimentally verified numerical model, four different timber-framed shear walls were simulated with FE models.Ministry of Science, Industry and Technology; Sanver Furniture, Decoration, Construction Forest Products CorporationThis study (01332STZ.2012-1 San-Tez project) was supported by the Ministry of Science, Industry and Technology. The authors express their gratitude to the ministry and to Sanver Furniture, Decoration, Construction Forest Products Corporation for their support of the project

Determination of The Modulus of Elasticity of Wooden Construction Elements Reinforced with Fiberglass Wire Mesh And Aluminum Wire Mesh

Laminated composite wooden construction elements were produced with 7 layers of Scots pine (Pinus sylvestris L.). Fiberglass wire mesh and aluminum wire mesh, which were used as reinforcement materials, were pressed with polyvinyl acetate (PVAc) and polyurethane-type adhesives between each Scots pine layer. The highest bonding strength values were obtained from laminated control specimens produced with polyurethane adhesive without using support materials (4.98 N/mm(2)) and laminated control specimens made with polyurethane adhesive without using support materials (4.39 N/mm(2)), respectively. The modulus of elasticity in bending perpendicular to the glue line values of all the specimens except the laminated control specimens produced with polyurethane adhesive without using support materials (14800 N/mm(2)) were lower than solid wood (6720 N/mm(2)). In contrast, in the experiments for the modulus of elasticity parallel to the glue line, the variables (adhesive, intermediary layer materials) used for all experiments and specimens were effective factors. Although the modulus of elasticity in bending parallel to the glue line values of all samples were higher than solid wood (6720 N/mm(2)), the maximum value was obtained in the laminated control specimens produced with polyurethane adhesive without using support materials (17800 N/mm(2)).WoSScopu

IMPACTS OF DIFFERENT JOINT ANGLES AND ADHESIVES ON DIAGONAL TENSION PERFORMANCES OF BOX-TYPE FURNITURE

The goal of this study was to determine the effects of different joint angles and adhesives on diagonal tension performances of the box-type furniture made from solid wood and medium density fiberboard (MDF). After drilling joints of 75º, 78º, 81º, 84º, and 87º degrees on Oriental beech, European oak, Scotch pine, and MDF samples, a diagonal tensile test was applied on corners glued with polyvinyl acetate (PVAc) and polyurethane (D-VTKA = Desmodur-Vinyl Trieketonol Acetate) according to ASTM D 1037 standard. With reference to the obtained results, the highest tensile strength was obtained in European oak with PVAc glue and joint angle of 84º, while the lowest value was obtained in MDF with D-VTKA glue and joint angle of 75º. Considering the interaction of wood, adhesive, and joint angle, the highest tensile strength was obtained in European oak with joint angle of 81º and D-VTKA glue (1.089 N.mm-2), whereas the lowest tensile strength was determined in MDF with joint angle of 75º and PVAc glue (0.163 N.mm-2). Therefore, PVAc as glue and 81º as joint angle could be suggested to obtain some advantageous on the dovetail joint process for box-type furniture made from both solid wood and MDF

Pediatric sudden sensorineural hearing loss: etiology, prognostic factors and treatment

Aim: Sudden sensorineural hearing loss (SSNHL) may have a negative impact on the language and psychological development of children, especially if it is not diagnosed early and treated promptly. This study were aimed to determine and compare the etiological factors, treatment outcomes and prognostic factors in the pediatric patients who were followed up with the diagnosis of SSNHL. Materials and Methods: The files of 28 children were analyzed retrospectively. In pure tone audiometry, the average of pure tone thresholds of 500 Hz, 1000 Hz, 2000 Hz and 4000 Hz were accepted as pure tone averages (PTAV). Patients' recovery status was determined according to Siegel criteria. Audiometric curve types were evaluated as ascending, descending, and flat. Results: The ages of patients with SSNHL was mean ± SD 14.89 ± 3.24 (min-max: 7 and 18). The pre-treatment PTAV was mean ± SD 55.27 ± 12.39 dB HL (min-max: 38.5 and 85.25 dB HL) and the PTAV after treatment was mean ± SD 23.13 ± 18.22 dB HL (min-max: 5 and 72.5 dB HL). Audiometric curve types were detected as descending curve (n: 11, 39.2%), ascending curve (n: 5, 17.9%), flat curve (n: 12, 44.9%). Eighteen (64.3%) patients had complete recovery, 8 (28.6%) patients had partial recovery, and 2 (7.1%) patients had no recovery after the treatment. Conclusion: The response to treatment was found to be high. Descending audiometric curve type was found as a positive prognostic factor. Although the presence of tinnitus was a better prognostic factor than the presence of vertigo

Determination of the Modulus of Elasticity of Wooden Construction Elements Reinforced with Fiberglass Wire Mesh and Aluminum Wire Mesh

Laminated composite wooden construction elements were produced with 7 layers of Scots pine (Pinus sylvestris L.). Fiberglass wire mesh and aluminum wire mesh, which were used as reinforcement materials, were pressed with polyvinyl acetate (PVAc) and polyurethane-type adhesives between each Scots pine layer. The highest bonding strength values were obtained from laminated control specimens produced with polyurethane adhesive without using support materials (4.98 N/mm(2)) and laminated control specimens made with polyurethane adhesive without using support materials (4.39 N/mm(2)), respectively. The modulus of elasticity in bending perpendicular to the glue line values of all the specimens except the laminated control specimens produced with polyurethane adhesive without using support materials (14800 N/mm(2)) were lower than solid wood (6720 N/mm(2)). In contrast, in the experiments for the modulus of elasticity parallel to the glue line, the variables (adhesive, intermediary layer materials) used for all experiments and specimens were effective factors. Although the modulus of elasticity in bending parallel to the glue line values of all samples were higher than solid wood (6720 N/mm(2)), the maximum value was obtained in the laminated control specimens produced with polyurethane adhesive without using support materials (17800 N/mm(2))

Design Strategy for Recycled Aggregate Concrete: A Review of Status and Future Perspectives

Currently, a number of disadvantages hampers the use of recycled concrete aggregates (RCA). The current review proves that concretes made with complete replacement of natural aggregate with RCA allow the production of high-quality concrete. One of the possibilities for improving concrete properties with RCA is the use of extended curing and pozzolanic materials with varying cement ratios. The potential use of RCA concretes is in the production of high-value materials that increase environmental and financial benefits. RCA have strong potential in the development of a new generation of concrete and stimulate economic activity in many countries in addition to optimizing natural resources. Economic benefits include minimal travel costs; cheaper sources of concrete than newly mined aggregates; reduction of the landfill area required for the placement of concrete waste; the use of RCA minimizes the need for gravel extraction, etc. The proposed strategy could be to sequentially separate demolition waste such as roof finishes, waterproof materials, interior and exterior materials, etc. Closing life cycles is the main approach used for efficient structures for the recycling and reuse of construction and demolition waste in the production and recovery of materials, especially when recycling and reusing materials. In the life cycle, the recycling of recovered materials allows them to be used for new construction purposes, avoiding the use of natural concrete aggregates. Government, design institutes, construction departments and project managers should be involved in the creation and use of RCA. In demolition and construction, the main players are the project owners. Their obligations, expectations and responsibilities must be properly aligned. For the past 20 years, recycled concrete aggregate from demolition and construction waste has been considered as an alternative to pure concrete in structural concrete to minimize the environmental impact of construction waste and demolition waste and the conversion of natural aggregate resources. It is now recognized that the use of RCA for the generations of concrete is a promising and very attractive technology for reducing the environmental impact of the construction sector and conserving natural resources. In the market, the selling price is not an obstacle for market applications of RCA, as there are scenarios in which their cost is lower than the cost of products made from conventional building materials. This is more of an acceptance factor in the market for recycled concrete aggregates. In this sector, the lack of identification, accreditation and uniform quality certification systems and their narrow application cause some marketing problems. With proper RCA preparation, concrete with standard physical and mechanical properties and performance characteristics can be obtained