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Effects of microencapsulated phase change material on physico-mechanical and thermoregulation performance of lightweight geopolymer concrete with zeolite and perlite
Get PDFThis study examines impact of microencapsulated phase change material (MPCM) additives on physical and mechanical characteristics of geopolymers produced using natural zeolite and slaked lime. The binder composition consists of 90 % zeolite and 10 % slaked lime, activated with NaOH at a Na/binder ratio of 14 % by weight. Basalt-based sand and perlite were used as aggregates with a water/binder ratio of 0.60. MPCM was added in varying proportions of 8 %, 16 %, and 24 % relative to the binder weight. Samples were molded in dimensions of 50 x 50 x 50 mm and 200 x 200 x 20 mm, then cured at 95 degrees C for 24 h. Differential Scanning Calorimetry (DSC) outcomes presented that geopolymer composite with MPCM has a melting degree of 26.45 degrees C and a melting enthalpy of 17.8 J/g. Fourier Transform Infrared Spectroscopy (FTIR) results confirmed physical integration of MPCM into geopolymer structure. The study also evaluated compressive strength, ultrasound pulse velocity (UPV), dry unit weight, and microstructural properties using Scanning Electron Microscopy (SEM) and Energy Dispersive Spectroscopy (EDS). Thermoregulation performance experiments demonstrated that the MPCMenhanced samples effectively moderated temperature fluctuations, maintaining lower temperatures for controlled heating and higher temperatures for natural cooling phases compared to the control sample. Thermal regulation capabilities of MPCM-infused geopolymers were evidenced by their property of absorbing and releasing heat, which is critical for energy-efficient building materials. Additionally, the durability and stability of the geopolymer matrix were enhanced by the uniform dispersion of MPCMs, which also improved the composite's mechanical performance. The successful integration of MPCMs highlights their potential in developing sustainable construction materials that contribute to energy savings and environmental conservation
The effect of finger puppet activity applied to children during high-flow nasal cannula oxygen therapy on anxiety and effect on phsysiological parameters. randomized controlled study
Get PDFAraştırma çocuklara yüksek akımlı nazal kanül oksijen (YANKO) tedavisi sırasında uygulanan parmak kukla aktivitesinin anksiyete ve fizyolojik parametrelere etkisini belirlemek amacı ile randomize kontrollü deneysel çalışma olarak yapılmıştır. Araştırma Düzce Üniversitesi Sağlık Uygulama ve Araştırma Merkezi ve Sakarya Eğitim ve Araştırma Hastanesi'nin Çocuk Klinikleri'nde Eylül 2023-Haziran 2024 tarihleri arasında gerçekleştirilmiştir. Araştırmanın örneklemini, yapılan güç analizi sonucu çalışmaya katılmayı kabul eden ve örneklem seçim kriterlerine uyan toplam 70 çocuk (deney=35, kontrol grubu=35) oluşturmuştur. Çocukların gruplara göre dağılımı rastlantısal olarak yapılmıştır. Deney grubunda yer alan çocuklara işlem sırasında parmak kukla aktivitesi uygulanmış olup, kontrol grubundaki çocuklara sadece rutin YANKO tedavisi işlemi uygulanmıştır. Her iki grubun uygulama öncesi, sırasında ve sonrasında fiziksel paremetreleri (vücut sıcaklığı, kalp atım hızı, oksijen satürasyonu) ölçülmüş ve iki gruba da "Çocukların Duygusal Dışa Vurumunu Değerlendirme Ölçeği" (ÇDDVDÖ) uygulanmıştır. Verilerin toplanmasında ebeveyn ve çocukların sosyodemografik özelliklerini belirlemek amacı ile ''Kişisel Bilgi Formu', işlem sırasında anksiyete düzeyini ölçmek için ÇDDVDÖ, fizyolojik bulgularını değerlendirmek için "Fizyolojik Parametreler Kayıt Formu'' kullanılmıştır. Araştırmada elde edilen veriler SPSS (Statistical Package for Social Sciences) for Windows 22.0 programı kullanılarak analiz edilmiştir. Araştırma verileri incelendiğinde, çocukların ÇDDVDÖ puanları açısından gruplar arasında istatistiksel olarak anlamlı bir fark saptanmıştır (p0,05), kalp atım hızı değerleri açısından anlamlı bir farklılık saptanmıştır (p0.05), a significant difference was detected in heart rate values between the groups (p<0.05). In conclusion, the finger puppet activity applied during HFNC therapy was found to reduce anxiety in children and to have a positive impact on physiological parameters. Based on these findings, the use of finger puppets as a non-pharmacological intervention is recommended for children receiving HFNC therapy in pediatric emergency departments, pediatric wards, and pediatric intensive care units
Analytical and simulation model of IEEE 802.11af standardfor cognitive radio sensor networks
Get PDFBu tez çalışmasında, öncelik sınıflarına sahip veriler için IEEE 802.11af teknolojisi tabanlı bilişsel radyo algılayıcı ağ önerilmektedir. IEEE 802.11af teknolojisinde Beyaz Uzay Cihazı (WSD), İstasyon (STA) ve Erişim Noktası (AP), lisanslı hizmetlere herhangi bir zararlı müdahaleye neden olmadan, televizyon beyaz spektrumu üzerinden fırsatçı bir şekilde iletişim kurar. Önerilen ağ yapısında; WSD'ler, STA ve AP, Beyaz Uzay Haritası (WSM) tarafından belirlenen beyaz alan spektrumu üzerinden iletişim kurmak amacıyla Frekans Bölmeli Çoklu Erişim (FDMA) tekniğini kullanır. WSD, çeşitli ortamlardaki sensörlerden sıcaklık, nem, basınç gibi verileri toplar. Öncelik sınıfı verinin aciliyet durumuna göre kırmızı, sarı ve yeşil olarak belirlenmiştir. Önerilen ağın analitik modeli elde edildikten sonra Riverbed Modeler kullanılarak benzetim modeli gerçekleştirilmiştir. Grafiksel sonuçlar, öncelik bazlı verilerin izlenmesi için herhangi bir spektrum maliyeti olmadan, önerilen ağın gecikme (0,17 s) ve enerji tüketimi (4,7 mJ/s) açısından geçerliliğini ve uygulanabilirliğini kanıtlamaktadır.In this study, a cognitive radio sensor network based on IEEE 802.11af technology is proposed for data with priority classes. In IEEE 802.11af technology, the White Space Device (WSD), Station (STA), and Access Point (AP) communicate opportunistically over the television white spectrum without causing any harmful interference to licensed services. In the proposed network structure; WSDs, STA and AP use the Frequency Division Multiple Access (FDMA) technique to communicate over the white space spectrum determined by the White Space Map (WSM). WSD collects data such as temperature, humidity, pressure from sensors in various environments. The priority class is determined as red, yellow and green depending on the urgency of the data. After the analytical model of the proposed network was obtained, the simulation model was implemented using Riverbed Modeler. The graphical results prove the validity and feasibility of the proposed network in terms of latency (0.17 s) and energy consumption (4.7 mJ/s) without any spectrum cost for monitoring priority-based data
Energy-Efficient Hybrid Adaptive Clustering for Dynamic MANETs
Get PDFMobile ad hoc network (MANET) is a wireless, mobile node network in which the nodes move randomly and operate without centralized management. In MANETs, the network structure increases the energy consumption of the nodes, which shortens the network lifetime and affects packet transmission. The process of clustering in MANETs (Mobile Ad-hoc Network) can be achieved through the division of the network into virtual groups, known as clusters. The Cluster Head (CH) of each cluster is in charge of data transmission within the cluster. In this study, a two-stage Hybrid Adaptive Clustering Algorithm for Dynamics MANETs (HACADM) is proposed to improve the network performance in MANETs. In the first stage, based on the Weighted Clustering Algorithm (WCA) for selecting optimal CHs, criteria such as node degree, neighborhood distance, power of battery and mobility are optimized using the Gravity Search Algorithm (GSA). In the second phase, the clustering is executed by identifying the member nodes and their roles of the selected CHs using the Enhanced Density Based Spatial Clustering of Applications with Noise (Enhanced-DBSCAN) algorithm, which is one of the unsupervised learning methods. Moreover, this approach serves to reduce the load on the CHs and enhance the stability of the cluster by selecting gateway nodes for inter-cluster communication. This study represents a significant step towards optimizing energy efficiency and extending network lifetime by enhancing the adaptability of clustering processes in MANETs under dynamic network conditions. The proposed HACADM method has the potential to enhance the performance of MANETs by ensuring a more balanced load distribution compared to existing clustering approaches. The HACADM method was compared with the EE-WCA, E-MAVMMF, TSDR and MORS-ASO methods using critical performance metrics such as remaining energy, end-to-end delay, packet delivery ratio and throughput. For example, experimental results on remaining energy show that the average energy consumption improvements of HACADM compared with EE-WCA, E-MAVMMF, TSDR and MORS-ASO are 46.38%, 18.35%, 13.08% and 8.33% respectively. Other Performance evaluation results also show that HACADM significantly contributes to the effective management of MANETs, extends the network lifetime and maintains high performance under dynamic network conditions
Unmasking metabolic clues: adipsin, irisin and osteopontin as biomarkers in polycystic ovary syndrome and their impact on metabolic dynamics: a case-control study
Get PDFObjectives: Polycystic ovary syndrome (PCOS) is a common endocrine disorder in women of reproductive age, often associated with metabolic alterations.This study assessed serum levels of adipsin, irisin, and osteopontin in patients with PCOS and examined their correlations with metabolic parameters. Material and methods: A case-control studywas conducted involving 96 women with PCOS and 80 healthy controls. Serum levels of adipsin, irisin, and osteopontin were measured; demographic, clinical, and metabolic characteristics were evaluated. Results: Patients with PCOS were significantlyyoungerthan controls (p < 0.001).The PCOS group included a significantly greater proportion of obese individuals (p = 0.013). Patients with PCOS exhibited elevated serum adipsin (p = 0.020) and reduced osteopontin (p < 0.001) levels relative to controls; obesity and age influenced these differences. Osteopontin demonstrated superior predictive power for PCOS diagnosis [area under the curve (AUC) = 0.802] compared with adipsin (AUC = 0.602). A combination of osteopontin and adipsin yielded the highest predictive value (AUC = 0.817) among double or triple biomarker combinations. Conclusions:This study identified potential associations among adipsin, osteopontin, irisin, and PCOS. Further research is warranted to elucidate their roles and clinical implications in PCOS and its metabolic alterations. The findings highlight the impact of age and obesity on these biomarkers and their relationships with PCOS, providing insight into the syndrome's complex pathophysiology
Plantar fascia avulsion fracture of the calcaneus in adolescence: a rare case report
Get PDFThis case report describes a rare avulsion fracture of the calcaneus involving the plantar fascia insertion in an adolescent patient following a sports-related injury. The patient presented with acute heel pain, and imaging confirmed a significant avulsion at the plantar fascia's calcaneal attachment. Unlike the more common Achilles tendon-related avulsion injuries, this case illustrates a less frequently recognized injury pattern in the pediatric population. Management was conservative, consisting of rest, immobilization, and a structured rehabilitation program. The patient achieved full recovery, returning to normal activities without residual symptoms. This case underscores the importance of considering plantar fascia avulsion fractures in adolescent patients with heel pain, particularly in the context of athletic trauma. This record is sourced from MEDLINE/PubMed, a database of the U.S. National Library of Medicin
Determination of heavy metal contamination in agricultural soils of Düzce province
Get PDFDüzce, Karadeniz Bölgesi'nin batı kısmında yer alan tarımsal faaliyetlerin yoğun olarak gerçekleştirildiği bir ildir. Bu çalışmada, Düzce ili kent merkezi ve ilçelerini temsil edecek şekilde seçilen 15 örnekleme noktasından tarım, 15 örnekleme noktasından ise tarım dışı alan toprağı numuneleri alınmıştır. Her bir örnekleme noktasında kompozit numuneler oluşturabilmek için, seçilen alanda zikzak bir desende belirli mesafelerde en az 5 noktadan, yerin 30 cm derinliğinde homojen bloklar şeklinde örnekler toplanmıştır. Çalışmada, toprak örneklerinin elementel analizleri indüktif eşleşmiş plazma optik emisyon spektroskopisi (ICP-OES) (Perkin Elmer AVİO 200) cihazı kullanılarak gerçekleştirilmiştir. Çalışmada elde edilen sonuçlar incelendiğinde hem tarım topraklarında hem de tarım dışı alan topraklarında en yüksek aritmetik ortalamalara sahip olan elementlerin sırasıyla Si, Al, Fe, Ca ve K elementleri olduğu, en düşük aritmetik ortalamaya sahip elementlerin ise Cd, As, Mo, Pb ve Sn olduğu anlaşılmıştır. Bölgede tarım ve tarım dışı alan topraklarının kirlenme derecesinin anlaşılabilmesi için çalışmada elde edilen sonuçlar Çevre, Şehircilik ve İklim Değişikliği Bakanlığı'nın Toprak Kirliliğinin Kontrolü Yönetmeliğinde belirtilen sınır değerleri ile karşılaştırılmıştır. Yapılan değerlendirmeler, sonuçların sınır değerlerden genellikle düşük olduğunu göstermiştir. Çalışmada metal kirliliği düzeylerinin anlaşılabilmesi amacı ile Zenginleşme Faktörü (EF), Jeobirikim İndeksi (lgeo), Kirlilik Faktörü (CF), Kirlilik Yük İndeksi (PLI) ve Potansiyel Ekolojik Risk Faktörü (ERI) ile Risk İndeksi (PERI) hesaplanmıştır. Kirlilik yükü parametreleri incelendiğinde yalnızca Mo, Cd, Sn, Sb elementleri için kirlenme tespit edilebilmiştir. Örneklenen toprakların kirletici kaynaklarının belirlenebilmesi için yapılan korelasyon ve temel bileşen analizi yöntemleri ile birlikte örnekleme bölgesi için hazırlanan dağılım haritaları incelendiğinde trafik, yanma, endüstri, tarımsal faaliyetler gibi kirletici kaynaklarının bölgedeki doğal toprak bileşimini etkilediği görülmüştür.Düzce is a province located in the western part of the Black Sea Region where agricultural activities are intensive. In the study, soil samples were collected from 15 sampling points selected to represent agricultural soil and 15 sampling points selected to represent non-agricultural soil in the city center and the districts of Düzce. In order to create homogeneous composite samples at each sampling point, samples were collected from at least 5 points at a depth of 30 cm at certain distances in a zigzag pattern. In the study, elemental analyses of soil samples were carried out using inductively coupled plasma optical emission spectroscopy (ICP-OES) (Perkin Elmer AVİO 200) device. When the results obtained in the study were examined, it was understood that the elements with the highest arithmetic means in both agricultural and non-agricultural soils were Si, Al, Fe, Ca and K, respectively, while the elements with the lowest arithmetic means were Cd, As, Mo, Pb and Sn, respectively. In order to evaluate the degree of pollution in agricultural and non-agricultural soils in the region, the results obtained in the study were compared with the threshold values specified in the Soil Pollution Control Regulation of the Ministry of Environment, Urbanization and Climate Change. It was observed that the results were mostly below the threshold values given in the relevant regulation. In the study, Enrichment Factor (EF), Geoaccumulation Index (Igeo), Contamination Factor (CF), Pollution Load Index (PLI), Potential Ecological Risk Factor (ERI), and Risk Index (PERI) were calculated to evaluate the levels of metal contamination. When the pollution load parameters were examined, pollution was detected only for Mo, Cd, Sn, Sb elements. When the distribution maps prepared for the sampling region were investigated together with the correlation and principal component analysis methods to identfy the pollutant sources of the sampled soils, it was observed that pollutant sources such as traffic, combustion, industry, and agricultural activities affected the natural soil composition in the region
Analysis of Turkish Pine Stumpage-based Auction Sales: A Case Study of İzmir Regional Directorate of Forestry
Get PDFThe study analyzed all Turkish pine stumpage-based auction sales conducted by 10 forest management directorates under the İzmir Regional Directorate of Forestry between 2020-2024. The analysis included all data on Turkish pine stumpage-based auction sales carried out from March 2020—when the General Directorate of Forestry introduced the new open-access e-auction system during the Covid-19 pandemic—until June 2024. To analyze the stumpage-based auction sales of Turkish pine by the forest management directorates, the auction revenues were converted to 2020 constant prices using the Producer Price Index for forest products and related services published by TUIK. When examining the 818 Turkish pine stumpage-based auction revenues analyzed in the study, the Bergama, Akhisar, and Manisa Forest Management Directorates ranked as the top three, respectively. In terms of the number of auctions, the ranking shifted to Manisa, Gördes, and Akhisar Forest Management Directorates. Regarding the total volume (m³) of standing timber offered for auction, the Manisa, Akhisar, and Gördes Forest Management Directorates outperformed the others. Lastly, when comparing revenue per unit, Bergama, Salihli, and Akhisar Forest Management Directorates achieved a more profitable production process in the relevant years compared to other directorates
Complete urethral rupture accompanying penile fracture: a case report
Get PDFIntroduction and importancePenile fracture is a rare urological emergency. It occurs due to the penis being subjected to force during intercourse or other causes. Treatment is usually surgical. Urethral injury accompanies 10-20% of cases. In this case, a complete urethral rupture accompanying a penile fracture is aimed to be presented.Presentation of caseA 45-year-old male patient presented to the emergency department with complaints of a snapping sound, pain, and sudden loss of erection during sexual intercourse. After a while, bleeding from the external meatus and inability to urinate were added to his complaints. Physical examination showed typical signs of penile fracture along with urethrorrhagia. The penile doppler ultrasound result was reported to be consistent with a penile fracture and uretral injury. Approximately one hour after presenting to the emergency department, the patient underwent surgery. Considering the possibility of urethral rupture, a urethroscopy was performed before fracture repair, revealing a urethral defect approximately 8 cm proximal to the external meatus. Surgical repair found a near-complete bilateral rupture of the corpus cavernosum and a complete urethral rupture. The urethral rupture and fracture area were repaired according to surgical procedure standards. No additional complaints or new pathologies were observed in the early postoperative follow-up. The patient was discharged with a catheter on postoperative day 3. On the 14th postoperative day, the patient's catheter was removed. At the 3-month follow-up, the patient had no urinary complaints, and the uroflowmetry test showed a Qmax of 35. No pathology was detected in the urethrography performed. At the one-year follow-up, the patient's International Index of Erectile Function (IIEF) score was 26, indicating no additional complaints.Clinical discussionComplete urethral rupture and bilateral corpus cavernosum rupture are rare urological emergencies, typically resulting from trauma applied to an erect penis. A physical examination, ultrasonography, and, when necessary, imaging techniques such as cystoscopy are the diagnostic modalities employed in such cases. Early surgical treatment has been shown to improve functional outcomes and reduce long-term complications.ConclusionEarly surgical intervention in the treatment of penile fractures not only preserves sexual function but also significantly reduces long-term complications. Urethral rupture should always be considered in fractures accompanied by urethrorrhagia and hematuria.Duzce University School of MedicineWe acknowledge the support and resources provided by Duzce University School of Medicine that facilitated the successful execution of this research
Green creativity and business sustainability: the influence of dynamic capabilities, technology adoption, business strategies and knowledge management
Get PDFPurposeThe increasing global emphasis on environmental sustainability necessitates a better understanding of the antecedents of green creativity (GC) and business sustainability (BSE). However, research on this topic is limited, and these antecedents have not been examined holistically. Considering this research gap, in this study, we examined the interconnected roles of green dynamic capabilities (GDC), green technology adoption (GTA), green business strategies (GBS) and green knowledge management (GKM) in influencing GC and BSE.Design/methodology/approachWe collected the research data through surveys applied to 874 companies operating in the manufacturing and service sectors in Turkey and analyzed the data using the partial least squares structural equation modeling (PLS-SEM) method.FindingsThe study shows that GDC positively influence GBS, GC and GKM. Additionally, GTA positively affects GBS, BSE and GKM. However, GBS only impacts GC, while GKM positively influences GC and BSE. Our mediation analysis results indicate that GBS mediates the relationships between GDC-GTA and GC. Furthermore, GBS mediates the relationship between GTA and BSE. Similarly, GKM mediates the relationships between GDC and GC-BSE. Finally, it was determined that GKM mediates the relationships between GTA and GC-BSE.Research limitations/implicationsThe focus of the research on T & uuml;rkiye limits the generalizability of the findings. Future research can examine the relationships between the variables in different geographical and industrial settings and provide deeper insights into the causal mechanisms underlying these relationships.Practical implicationsThe analysis results of the research provide actionable insights for companies aiming to improve their sustainability practices. In addition, managers can use GDC and GTA to strengthen GBS and GKM, thus realizing their positive impacts on GC and BSE. The importance of integrating green strategies and knowledge management to take environmental challenges into account is emphasized.Originality/valueThe research is one of the important studies that comprehensively examine the interaction between GDC, GTA, GBS and GKM in the positive impacts of GC and BSE. The research provides insights into green transformation efforts in emerging economies, expanding the literature beyond the manufacturing sector to include the service sector.SME Development Organization of Turkey (KOSGEB)We sincerely thank the SME Development Organization of Turkey (KOSGEB) for their valuable support in providing essential data for this study. Their contributions have significantly enriched the foundation of our research, facilitating a more comprehensive and robust analysis