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Determination of Excavation Volume Using UAV-Based PPK Method in Open Mining Sites Tatlıdere Forests in Düzce
Get PDFTaş ocaklarında yapılan faaliyetler sonrası meydana gelen yüzey değişimlerinin (materyal hacmi) belirlenmesinde uzaktan algılama teknolojileri, maliyet-etkin, hızlı ve kolay çözümler sunma potansiyeli taşımaktadır. Topografyanın engebeli ve ulaşılması güç olduğu alanlarda yersel ölçüm tekniklerini kullanmak zorluklara neden olmaktadır. Bu gibi durumlarda uzaktan algılama tekniklerinin kullanımını olmazsa olmaz kılmaktadır. Coğrafi yapısı, uydu bazlı konumlamaya müsait olmayan alanlarda ölçü sonrası veri değerlendirme (Post Processing Kinematic-PPK) ölçüm tekniği diğer fotogrametri yöntemlerine alternatif çözüm sağlamaktadır. Bu çalışmada İHA-tabanlı PPK yönteminin taş ocağı işletmeciliğindeki kazı hacminin hesaplanmasında kullanılabilirliği incelenmiştir. Çalışma alanı olarak, işletmesi tüzel kişiliğe ait Tatlıdere (Düzce) Orman İşletme Şefliği’ndeki taş ocağı seçilmiştir. Çalışmada DJI Phantom 4 RTK marka ve PPK uygulama modülü sahip insansız hava aracı (İHA) kullanılarak, taş ocağında 30 Eylül 2021 ve 19 Mayıs 2022 tarihlerinde (yaklaşık 7 aylık süreci kapsayan) PPK uçuş modunda toplam iki uçuş gerçekleştirilmiştir. Taş ocağı işletmeciliği için önemli olan materyal hacmi hesaplanmış, iki uçuş zaman aralığındaki kazı miktarı 104,170 m³ ve kazı alanı ise 44,348 m2 bulunmuştur. Elde edilen sonuçlar doğrultusunda taş ocağı işletmeciliğinde İHA sistemleri veri elde etmede zaman ve iş güvenliği açısından kullanmalıdır.Remote sensing technologies have the potential to provide cost-effective, fast, and easy solutions for the determination of surface changes (material volume) after quarrying (open-pit mine) activities. In areas where the topography is rugged and difficult to access, the use of ground measurement techniques causes difficulties. In such cases, the use of remote sensing techniques is indispensable. The Post Processing Kinematic (PPK) measurement technique provides an alternative solution to other photogrammetry methods in areas whose topography is not suitable for satellite-based positioning. This study investigates the applicability of the UAV based PPK method for the calculation of cut volume in quarry operations. The study area was selected as a quarry located within the boundaries of Tatlıdere Forestry Operation Chief in Düzce province and operated by a legal entity. Using a DJI Phantom 4 RTK unmanned aerial vehicle (UAV) with a PPK application module, a total of two flights in PPK flight mode were performed at the quarry on 30 September 2021 and 19 May 2022 (covering a period of approximately 7 months). The material volume, which is important for quarry operation, was calculated and the excavation volume in the two flight time intervals was found to be 104.170 m³ and the cut area was found to be 44.348 m2. According to the results obtained, UAV systems should be used in quarry management in terms of time and work safety in obtaining data
Clinical Characteristics of Cases Developing Neonatal Pneumothorax: 10 Years of Experience
Get PDFAim: Pneumothorax is a serious emergency condition that increases mortality and morbidity due to the accumulation of air between the visceral and parietal pleura layers. Neonatal pneumothorax is more frequently encountered in neonates admitted to neonatal intensive care units. It is known that the most important risk factors are prematurity and ventilation with a bag mask. Material and Method: Forty-two pneumothorax cases followed in the neonatal intensive care unit (NICU) were included in our study. The characteristics, risk factors, treatment methods and prognoses of the cases were retrospectively analyzed. Results: Twenty eight of the cases (66.67%) were male, and Pneumothorax developed within the first 3 days of life in 41 cases (97.61%). Nineteen cases (45.24%) were premature, 16 cases (38.10%) underwent resuscitation at birth, and 15 cases (35.71%) received surfactant therapy. An intercostal chest tube was placed for treatment in 34 cases (80.95%), and invasive mechanical ventilation was required in 33 cases (78.57%). Thirty six cases (85.71%) were regained the health, while those who passed away were found to be more premature. Conclusion: In our study, prematurity, resuscitation at birth, and surfactant therapy were identified as risk factors for neonatal pneumothorax. Newborns with these risk factors should be closely monitored, and neonatal pneumothorax should be kept in mind if respiratory distress develops
Ekonomik Dinamikler ve Doğurganlık Arasındaki İlişki: Türkiye'de Varoluşsal Bir Sorun Olarak Bebek Kıtlığı
Get PDFSpanning from the classical insights of Malthus and Marx to the contemporary perspectives of Dumont and Becker, theorists have consistently underscored the pivotal role of economic factors in explaining fertility trends, weaving a narrative that connects historical and modern economic theories in the study of demographic dynamics. This study examines the impact of economic factors on Türkiye's fertility rates from 1990 to 2022, focusing on how changes in the consumer price index, GDP per capita, and social protection expenditure have influenced population trends. As more than one structural break was observed in the series, Clemente Montanes Reyes, Hatemi-J and Maki analyses were carried out. The results of the study do not indicate that the fertility rate in Türkiye is significantly affected by economic factors. No evidence of long-run cointegration between these variables was found. Therefore, changes in economic factors have little or negligible direct impact on the fertility rate. This research offers a crucial benchmark for shaping fertility policies in both developed and developing nations, as it thoroughly examines how economic progress influences population trends. These results highlight the complex dynamics of fertility and underline the need to understand the effects of increased female labor force participation, childcare costs, fertility anxiety and work-family conflict fertility decline.Malthus ve Marx'ın klasik görüşlerinden Dumont ve Becker'in çağdaş perspektiflerine kadar uzanan teorisyenler, ekonomik faktörlerin doğurganlık eğilimlerini açıklamadaki önemli rolünü sürekli olarak vurgulamış, demografik dinamiklerin incelenmesinde tarihsel ve modern ekonomik teorileri birbirine bağlayan bir anlatı oluşturmuşlardır. Bu çalışma, 1990'dan 2022'ye kadar ekonomik faktörlerin Türkiye'deki doğurganlık oranları üzerindeki etkisini inceleyerek, tüketici fiyat endeksi, kişi başına düşen GSYİH ve GSYİH'nın yüzdesi olarak sosyal koruma harcamalarındaki değişimlerin nüfus eğilimlerini nasıl etkilediğine odaklanmaktadır. Serilerde birden fazla yapısal kırılma gözlemlendiği için Clemente Montanes Reyes, Hatemi-J ve Maki analizleri gerçekleştirilmiştir. Çalışmanın sonuçları, Türkiye'deki doğurganlık oranının ekonomik faktörlerden önemli ölçüde etkilenmediğini göstermektedir. Bu değişkenler arasında uzun vadeli bir eşbütünleşme kanıtı bulunamamıştır. Dolayısıyla, ekonomik faktörlerdeki değişikliklerin doğurganlık oranı üzerinde çok az veya ihmal edilebilir düzeyde doğrudan bir etkisi vardır. Bu araştırma, hem gelişmiş hem de gelişmekte olan ülkelerde doğurganlık politikalarının şekillendirilmesi için önemli bir kıstas sunmakta, ekonomik gelişmenin nüfus eğilimlerini nasıl etkilediğini kapsamlı bir şekilde incelemektedir. Bu sonuçlar, doğurganlığın karmaşık dinamiklerini ortaya koymakta ve artan kadın işgücüne katılımı, çocuk bakım maliyetlerini, doğurganlık kaygısını ve iş-aile çatışmasının doğurganlık düşüşü üzerindeki etkilerini anlamanın önemini vurgulamaktadır
Biochemical and structural differences between C3 cotyledons and C4 leaves in species of Salsoloideae (Chenopodiaceae)
Get PDFC4 plants had evolved from C3 ancestors in at least more than 60 independent lineages of angiosperms, most probably in response to decreasing levels of atmospheric CO2 and environmental conditions promoting photorespiration. Salsola, Petrosimonia, and Cyathobasis genera of Salsoloideae subfamily contain some species with C3 cotyledons followed by C4 leaves. The aim of this study was to determine and compare the biochemical and structural differences between C3 cotyledons and subsequent C4 leaves in these genera. The results showed that there were isopalisade C3 cotyledons in Salsola grandis and isolateral C3 cotyledons in Cyathobasis fruticulosa, while salsoloid type C4 Kranz anatomy was present in subsequent leaves. Petrosimonia nigdeensis had dorsiventral C3 cotyledons and salsoloid-type C4 leaves. The proteins of C4 isoform phosphoenolpyruvate carboxylase (PEPC) and pyruvate orthophosphate dikinase (PPDK) enzymes were absent or very sparse in C3 cotyledons of these species, whereas they were abundant in their C4 leaves. The proteins of photorespiratory isoform glycolate oxidase (GOX) and glycine decarboxylase-H subunit (GDC-H) were generally higher in cotyledons than leaves. The protein level of photosynthetic isoform ribulose 1,5-bisphosphate carboxylase/oxygenase (Rubisco) enzyme was lower in C4 leaves compared to C3 cotyledons. Transcript levels of these enzymes were generally consistent with their protein content except for GOX in S. grandis and S. tragus and glycine decarboxylase complex (GDC) in S. tragus. As a result, we demonstrated that not only the protein and transcript levels of the enzymes required for C4 pathway increased, but also those levels of C3 and photorespiratory enzymes decreased during the transition from C3 cotyledons to C4 leaves. These results are considered significant in terms of shedding light on the understanding of evolutionary transition from C3 to C4 biochemical pathway in a single plant and contributing to C4 engineering
Modulation of Brain-derived Neurotrophic Factor and Nerve Growth Factor Gene Expression in the Hippocampus and Cortex Regions of Rats with Penicillin-induced Experimental Epilepsy: The Effect of Adenosine Triphosphate-sensitive Potassium Channels
Get PDFObjective:The objective is to investigate the effect of adenosine triphosphate (ATP)-sensitive potassium (KATP) channels on brain-derived neurotrophic factor (BDNF) and nerve growth factor (NGF) gene expression in the hippocampus and cortex regions using a penicillin-induced epilepsy model. Materials and Methods:The study included four groups, control (C), epilepsy (E), epilepsy-opener (E-O), and epilepsy-blocker (E-B), and three subgroups, 1st day, 4th day, and 8th day after the seizure. The hippocampus and cortex were dissected from all animals and BDNF and NGF messenger ribonucleic acid (mRNA) expression levels were quantified using quantitative polymerase chain reaction (qPCR). Results:The relative gene expression of the NGF gene evaluated in hippocampal tissues was found to be significantly higher in the epilepsy 1st-day group compared with the C group (P < 0.05). The relative gene expression of the NGF gene in cortex tissues was found to be significantly higher in the epilepsy 8th-day group compared with the C group (P < 0.05). The relative gene expression of the BDNF gene in hippocampal tissues was also significantly higher in the epilepsy 1st-day group compared with the C group (P < 0.05). BDNF gene expression levels in the cortex region were significantly higher in the E group on the 8th day, in the E-O group on the 1st, 4th, and 8th days, and in the E-B group on the 1st day; BDNF gene expression level was also significantly higher in the E-B group on the 8th day compared with the C group (P < 0.05). Conclusion:KATP channels play a modulatory role in the expression levels of BDNF and NGF genes in the cortex over an extended period of 8 days, parallel to their efficacy observed in the hippocampus on day 1. These mechanisms need to be thoroughly investigated and emphasized due to their importance.Bolu Abant Idot;zzet Baysal University Research Foundation [2019.10.01.1408]This study was financed by the Bolu Abant & Idot;zzet Baysal University Research Foundation (BAP-grant number: 2019.10.01.1408)
Monitoring Arsenic Concentrations in Airborne Particulates of Selected Landscape Plants and Their Potential for Pollution Mitigation
Get PDFAmong the most dangerous pollutants in terms of environment and living health are heavy metals, the concentrations of which have been continuously increasing within nature due to anthropogenic effects in recent years. Arsenic (As), one of the most harmful heavy metals, is extremely dangerous to living beings even at low concentrations. Therefore, observing the change of As pollution in the airborne and reducing pollution are priority research topics. In this study, the usability of some landscape plants for observing and decreasing the alteration of As pollution in the airborne was evaluated. Within the scope of the study, changes in As concentration in five landscape plants growing in D & uuml;zce, one of the most polluted cities in Europe as stated by the World Air Pollution Report, were examined in terms of species, organs, directions, and age range over the last 60 years. As a conclusion of the study, As concentration in samples taken from Fraxinus excelsior, Tilia tomentosa, and Pseudotsuga menziesii remained below detectable limits. It was concluded that Cedrus atlantica and Robinia pseudoacacia are not suitable biomonitors for monitoring the change in As pollution, but they can be used effectively to reduce As pollution since they can accumulate very high levels of As
The usage of carbon black (CB) obtained from agricultural wastes in the manufacture of bicycle tires and the examination of the physico-mechanical properties of the manufactured material
No full textDünya nüfusundaki hızlı artış ve buna bağlı olarak tüketim oranlarının yükselmesi, lastik endüstrisini sürdürülebilir ve çevre dostu çözümler aramaya yönlendirmiştir. Atık ürünlerin çevreye verdiği zararların artan farkındalığıyla lastik üreticileri ve araştırmacılar doğal atık malzemelerin kauçuk karışımlarında kullanımını incelemeye başlamıştır. Karbon siyahının alternatif doğal malzemelerle ikamesi, atık malzemelerin geri dönüşümünü teşvik ederek karbon ayak izini azaltmak için umut verici bir çözüm sunmaktadır. Bu doğrultuda, tarımsal atıklar, gıda kabukları ve selüloz gibi yenilenemeyen biyolojik atıklarla ilgili geri dönüşüm çalışmaları önemli ölçüde artmıştır. Tarımsal bir atık ürün olan fındık kabukları, düşük maliyetleri, yüksek karbon içerikleri ve çeşitli endüstriyel uygulamalardaki çok yönlülükleri nedeniyle geri dönüşüm çalışmalarında sıklıkla tercih edilmektedir. Bu çalışmada, bisiklet lastiği üretiminde bir katkı maddesi olarak fındık kabuğundan elde edilen karbonun (FK) kullanımı potansiyeli araştırılmıştır. FK'nin lastik karışımlarında kullanılabilirliği, bisiklet lastiği formülasyonlarında yaygın olarak kullanılan karbon siyahı (CB) ile karşılaştırılarak değerlendirilmiştir. Bisiklet lastiği formülasyonları, toplam karbon dolgu içeriği sabit tutularak 28 phr seviyesinde hazırlanmıştır. Başlangıçta, 28 phr ticari karbon siyahı ve 0 phr FK kullanılmıştır. Daha sonraki formülasyonlarda, karbon siyahı içeriği sırasıyla 21, 14, 7 ve son olarak 0 phr'ye düşürülmüş; buna karşılık FK içeriği sırasıyla 7, 14, 21 ve 28 phr'ye çıkarılarak azalan ticari karbon siyahının yerini almıştır. Hazırlanan beş farklı formülasyon, Mooney Viscosity (MV), Mooney Scorch (MS), reolojik testler, fizikomekanik testler, FTIR (Fourier Transform Infrared Spectroscopy), SEM (Scanning Electron Microscopy), TGA (Thermogravimetric Analysis), payne etkisi, plunger testi ve yol mukavemet testi gibi çeşitli analitik teknikler kullanılarak karakterize edilmiştir. Tüm formülasyonlarla lastikler başarılı bir şekilde üretilmiştir. 7 phr FK-21 phr CB içeren formülasyon hem fiziksel hem de dinamik özellikler bakımından tatmin edici sonuçlar sunmuştur. Bisiklet lastiklerinin kompozisyonlarında FK miktarının artmasının mekanik performansı azalttığını, ancak yine de bisiklet lastiği uygulamaları için gereken performans gerekliliklerini karşıladığını göstermektedir. Bu çalışmanın bulguları, FK'nin CB yerine kullanılmasının sürdürülebilir bir alternatif olduğunu ortaya koymuştur.The rapid increase in the world population and corresponding rise in consumption rates have driven the tire industry to seek sustainable and environmentally friendly solutions. With growing awareness of the harm that waste products inflict on the environment, tire manufacturers and researchers have begun to investigate the use of natural waste materials in rubber compounds. The substitution of carbon black with alternative natural materials offers a promising solution for reducing carbon footprints by promoting the recycling of waste streams. In this context, recycling studies on biological wastes such as agricultural residues, food husks, and cellulose have grown substantially. Hazelnut shells, an agricultural waste product, are frequently preferred in recycling studies due to their low cost, high carbon content, and versatility in various industrial applications. In this study, the potential of using carbon obtained from hazelnut shells (HSC) as an additive in bicycle tire production was investigated. The usability of HSC in tire compounds was evaluated by comparing it with Carbon Black (CB), a commonly used filler in bicycle tire formulations. Bicycle tire formulations were prepared by maintaining a constant total carbon filler content of 28 parts per hundred rubber (phr). Initially, 28 phr of commercial carbon black and 0 phr of HSC were used. In subsequent formulations, the carbon black content was progressively reduced to 21, 14, 7, and finally 0 phr, while the HSC content was correspondingly increased to 7, 14, 21, and 28 phr to replace the reduced commercial carbon black. The five different formulations were characterized using various analytical techniques, including Mooney Viscosity (MV), Mooney Scorch (MS), rheological tests, physical-mechanical tests, Fourier Transform Infrared Spectroscopy (FTIR), Scanning Electron Microscopy (SEM), Thermogravimetric Analysis (TGA), payne effect measurements, plunger tests, and rolling resistance tests. Tires have been successfully produced with all formulations. The formulation containing 7 phr HSC and 21 phr CB exhibited satisfactory results in both physical and dynamic properties. The results indicate that increasing the HSC content in bicycle tire compositions reduces mechanical performance, yet still meets the performance requirements for bicycle tire applications. The findings of this study demonstrate that HSC can serve as a sustainable alternative to CB
Evaluation of accessory transverse foramen in the western black sea population
Get PDFCervical bölgede 7 tane vertebra bulunmaktadır. Bu vertebraları diğer vertebra'lardan ayıran en belirgin özellik processus (proc.) transversus'larında foramen (for.) transversarium bulunmasıdır. For. transversarium'un içerisinden arteria (a.) vertebralis, vena (v.) vertebralis ve etrafındaki plexus sympaticus geçmektedir. A. vertebralis altıncı cervical vertebra'nın for. transversarium'undan girerek yukarıya doğru yükselir. For. transversarium a. vertebralis'in durumundan etkilenerek şekil, boyut bakımından farklılıklar gösterebildiği gibi for. transverarium'daki değişiklikler de a. vertebralis'in çeşitli varyasyonlar göstermesine neden olabilmektedir. Literatürde pek çok araştırmacı for. transversarium varyasyonları konusunda hemfikirdir. Çalışmamızdaki amaç aksesuar foramen transversarium (AFT) olarak adlandırılan birden fazla for. transversarium görülme durumunu radyolojik olarak incelemektir. Çalışmada yaş ortalaması 51,52 olan 100 kadın ve 100 erkek toplam 200 bireyin BT görüntüleri retrospektif olarak incelendi. AFT gözlemlenen kişiler kaydedildi ve her AFT'nin enine çapları ölçüldü. Elde edilen veriler SPSS 26.0 programı ile analiz edildi. Analiz sonuçlarına göre 49 erkek 46 kadın toplam 95 kişide AFT gözlendi. Cinsiyet ile AFT arasında ve cinsiyet ile AFT enine çap değerleri arasında istatistiksel olarak anlamlı bir fark bulunmadı (p>0,05). İki cinsiyette de en sık AFT görülen vertebra C6 olarak belirlendi. Çalışmamızın amacı röntgen ve BT taramalarının yorumlanması yoluyla boyun bölgesinde yapılacak cerrahi müdahalelerde yapıların daha iyi belirlenmesi ve uygun girişimin seçilmesinde yol göstermektir. Anahtar Sözcükler: Cervical vertebra, Foramen transversarium, Aksesuar foramen transversarium, Bilgisayarlı tomografiThere are 7 vertebrae in the cervical region. The most distinctive feature that distinguishes these vertebrae from other vertebrae is the presence of foramen (for.) transversarium in their processus (proc.) transversus. Arteria (a.) vertebralis, vena (v.) vertebralis and plexus sympaticus pass through the for. transversarium. A. vertebralis enters from the transverse foramen of the sixth cervical vertebra and rises upwards. Transverse foramen may differ in shape and size depending on the condition of the a. vertebralis, and changes in the foramen transverarium may cause the a. vertebralis to show various variations. Many researchers in the literature agree on the variations of transverse foramen. The aim of our study is to examine the condition of multiple transverse foramen, called accessory transverse foramen (AFT), radiologically. In the study, CT images of 100 women and 100 men, a total of 200 individuals, with an average age of 51.52, were retrospectively examined. Individuals observed AFT were recorded and transverse diameters of each AFT were measured. The obtained data were analyzed with SPSS 26.0 program. According to the analysis results, AFT was observed in 49 men and 46 women, a total of 95 people. There was no statistically significant difference between gender and AFT and between gender and AFT transverse diameter values (p>0.05). The vertebra C6 was determined as the most common AFT in both sexes. The aim of our study is to guide the better determination of structures and the selection of appropriate intervention in surgical interventions to be performed in the neck region through the interpretation of x-ray and CT scans
Advancing research on knowledge management in family business: a comprehensive review and future agenda
Get PDFPurposeThis research aims to analyze the development patterns of knowledge management (KM) literature in the context of family businesses (FB) with objective and quantitative data. For this purpose, it aims to fill the gaps in the existing literature and develop a more systematic understanding of the effects of KM on FB by utilizing the bibliometric analysis method and the theory, context, characteristics and methodology (TCCM) model.Design/methodology/approachWe conducted a systematic literature review (SLR) of published works indexed in the Clarivate Web of Science (WOS) and Elsevier Scopus databases to identify, evaluate and map research at the intersection of KM and FB. We analyzed the data using performance analyses, bibliometric analyses, TCCM and driver analyses.FindingsWe identify the most influential countries, journals, institutions and authors with performance analyses. Using co-citation and co-occurrence analysis, we generate insights about the literature at the intersection of KM and FB research. Based on TCCM and driver analyses, we identify theories, contexts, antecedents, outcomes, methodologies and critical drivers at this intersection, providing a detailed field pattern. We conclude this article by developing an agenda for future research.Originality/valueThis study is the first to examine the KM literature in FB from a holistic, systematic and objective perspective. Bibliometric analyses, the TCCM framework and driver analyses were applied to 207 articles obtained from the Web of Science and Scopus databases. Unlike previous literature, this study mapped theoretical, contextual, and methodological gaps in a multi-layered manner and suggested new areas for research. The study provides a more holistic framework for understanding the effects of KM on FB, thereby eliminating conceptual disorganization in the field. Thus, an original and future-oriented research agenda on the evolution of the KM-FB literature was presented
Defective topological spaces: A novel framework for topological spaces with incomplete information [2]
Get PDFRecent years have seen a surge of interest in representing and reasoning about uncertain information through extended versions of classical mathematical techniques. In this paper, we introduce the concept of defective topological spaces, which is a novel theory motivated by the problem of approaching a topological space with incomplete knowledge of its open sets. In order to address this problem, we define the concepts of exactly and possibly open sets. Furthermore, we investigate the categorical structure of defective topological spaces, and extend several concepts from classical topological spaces, including continuity, convergence, and separation axioms to defective topological spaces