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Investigation of thermal insulation and sound absorption properties of polymer foam added bicomponent yarns
No full textIn the study, it was aimed to produce bicomponent yarns which were produced with 1%, 2%, and 3% additive ratios of low-density polyethylene (LDPE) foam for insulation applications. Polymer foam was added for the first time into a bicomponent yarn structure. The bicomponent spinning was performed according to the sheath and core bicomponent melt spinning. Knitted fabrics were produced from bicomponent yarns with garter stitches to evaluate the thermal insulation and sound absorption properties. Thermal measurements were carried out with two different principles according to the JIS R 2618 standard (hot wire method) with a Thermal Conductivity Meter (QTM-710) and Alambeta test instrument. The lowest thermal conductivity coefficient factors (0.063 and 0.060 W/mK) were obtained according to the JIS R 2618 standard and Alambeta test instrument, respectively. Sound absorption properties were performed with ASTM E1050-12 standard with BSWA Impedance Tube Kit Type SW 260 with the small tube setup. The sound absorption coefficient was improved with the addition of polymer foam into the bicomponent yarn structure
How customers' paradoxical expectations affect service robot usage intention? A moderated mediation model
No full textThis study examines the influence of customers' paradoxical expectations on their service robots' usage intention in restaurants. In addition, it investigates the role of anthropomorphism perception and customers' attitudes in these effects. The results indicate that customers' expected performance efficacy positively affects their usage intention, while their expected realistic threat negatively affects them. Furthermore, expected performance efficacy indirectly positively affects usage intention through attitudes. In contrast, expected realistic threats indirectly negatively impact their usage intention through attitudes. The perceived anthropomorphism of service robots dampens the positive relationship between expected performance efficacy and their attitudes. However, anthropomorphism mitigates the inverse relationship between expected realistic threat and their attitudes. Consequently, the indirect effect of expected performance efficacy and realistic threat on intention to use is moderated by anthropomorphism. The findings provide valuable theoretical and practical insights to scholars and restaurant managers
Nonpharmacological aspects of intravitreal dexamethasone implant injections: A Retrospective Study of 3,430 Injections and Complications
No full textPurpose:This study aims to evaluate the nonpharmacological safety profile of intravitreal dexamethasone implants in cases with different etiologies.Methods:This retrospective university-based study analyzed clinical reports of patients receiving 0.7 mg dexamethasone implant injections between 2013 and 2023. The study recorded patient demographics, injection indications, and follow-up data. Complications caused by the injection procedure and adverse events other than pharmacological side effects within a 3-month period were included.Results:In this study, 3,430 dexamethasone implant injections were made into 1,471 eyes of 1,091 patients. Nonpharmacological complications developed in 611 injections (17.8%). Subconjunctival hemorrhage was noted as the leading nonpharmacological complication (n = 576, 16.8%). Sight-threatening 35 nonpharmacological adverse events and complications (1.0%) were recorded. Cases of anterior chamber migration, vitreous hemorrhage, retinal detachment, endophthalmitis, hypotony, and implant misplacement were observed. Cases requiring intensive treatments and additional surgical interventions were encountered.Conclusion:The injection of the dexamethasone implant may lead to nonpharmacological complications caused by the mechanical impact of the injection or improper positioning of the implant, potentially resulting in vision loss. Severe outcomes such as corneal decompensation, retinal detachment, and endophthalmitis can ensue, emphasizing the gravity of these complications. Careful selection of patients and adherence to proper injection techniques are essential in reducing these risks
Power measurements based on hybrid haar transform-prony method
No full textPower and power quality are among the most important concepts in electrical systems. This paper introduces a novel approach for power measurements or calculations in energy systems, employing the discrete Haar transform and Prony method. The technique stands out by offering an enhanced representation of the power spectrum. This improvement is achieved through the successful decomposition of the frequency spectrum. Unlike Fourier series, this method captures frequencies that are not merely integer multiples of the main harmonic, leading to a more comprehensive depiction of the power spectrum. To verify the effectiveness of the proposed method, simulations were performed on synthetic and real data and results with high accuracy were obtained. The technique demonstrates its prowess in accurately characterizing power spectra, showcasing its potential for applications in electrical systems where a more nuanced and precise analysis of frequency components is essential for a comprehensive understanding of the system behavior
Sustainable use of wetlands: A comparative analysis of Marmaracık (Bursa) and Lake Suğla (Konya)
No full textBu çalışma Konya ilindeki Suğla Gölü ve Bursa ilindeki kurutulan Marmaracık Gölü’nde ekosistem, sürdürülebilirlik, sulak alan dönüşümü ve bu dönüşümün beraberinde getirdiklerini incelemeyi amaçlamaktadır. Suğla Gölü çevresine önemli katkılar sağlayan bir sulak alan olmasına rağmen alanla ilgili yapılan çalışmalar daha çok fiziki odaklı olmuş, bütüncül olarak göl etkileşim sahasını inceleyen bir çalışma yapılmamıştır. Marmaracık Kurutma Sahası ile alâkalı arkeolojik kazı çalışmaları ve fiziki coğrafya çalışmaları yapılmış, ancak bu çalışmalar geniş alanları incelerken bu alanı yüzeysel olarak değinmekten ileri gitmemiştir. Alandaki göl ve etkileşim sahası bütüncül incelenmemiştir. Söz konusu iki sulak alanın doğal olduğu dönemlerde ve dönüşümden sonraki değişimleri incelenmemiştir. Bu çalışmada göl çevresi insan-çevre ilişkileri incelenmiştir. Çalışma şu sorulara cevap aramıştır: göl çevresi insan-çevre ilişkileri nasıldı, bu ilişki gölle birlikte nasıl dönüşmüştür? Değişimler sürdürülebilir kalkınma hedefleriyle uyumlu mudur? Değişimler yöre yaşayanları ve yönetici ilişkilerine nasıl yansımıştır? Alandaki sulak alanla bağlantılı yerleşme tarihleri nasıl şekillenmiştir? Bu soruları yanıtlamak için alana çeşitli zamanlarda üç yıl saha çalışmaları yapılmıştır. Saha çalışmalarında etnografik yöntem kullanılmış, yöre insanlarından edinilen bilgiler betimsel analiz yöntemiyle metin içinde sunulmuştur. Araştırma sonucunda iki sulak alanın doğal süreçlerinde yöre yaşayanları ile sıkı bağlar kurdukları, bu bağların kültürel kodlara işlediği, sulak alanlardaki dönüşümle birlikte fiziki unsurların tümü gibi bağlarında dönüştüğü görülmüştür. Söz konusu dönüşümlerin genellikle negatif doğrultulu ve yeni problemler yaratıcı olduğu görülmüştür. Kâr zarar dengesinin yönetici-halk arasında halk aleyhinde dağıldığı, halkın alan kullanımının yasaklandığı ya da kısıtlandığı ve sonucunda yönetici-yöre halkı çatışmasının giderek derinleştiğine tespit edilmiştir.This study aims to examine the ecosystem, sustainability, wetland transformation, and the implications brought about by this transformation in Lake Suğla and the dried Marmaracık. Although Suğla Lake is an important wetland area that contributes significantly to its surroundings, previous studies have predominantly focused on physical aspects, and there has been no comprehensive study examining the entire lake interaction zone holistically. Archaeological excavations and physical geography studies have been conducted regarding the Marmaracık dried area; however, these studies have generally only superficially addressed this area while examining broader areas. The lake and its surrounding interaction zone have not been comprehensively studied. The changes in these two wetland areas during their natural states and after transformation have not been studied. To fill this gap, the humanenvironment relationships around the lakes have been studied. The study has sought answers to the questions: What were the human-environment relationships around the lake? How have these relationships transformed with the lake? Are these changes compatible with sustainable development goals? How have these changes impacted local residents and administrators relations? How have settlement histories related to the wetland area evolved over time in the area? Fieldwork has been conducted in the area at various times over a period of three years. Ethnographic methods were employed during the fieldwork, and the data obtained from local residents is presented within the text using descriptive analysis methods. The research findings indicate that local residents have established strong connections with the natural processes of two wetland areas, with these connections becoming ingrained in cultural codes. Alongside the transformation of the wetland areas, these connections, like all physical elements, have undergone change. It has been observed that these transformations have been unsuccessful sustainability generating new problems. The balance of profit and loss has skewed in favor of the authorities over the local population, resulting in restrictions or prohibitions on local land use. Consequently, there has been a deepening conflict between the authorities and the local communities
Assessment of atmospheric concentrations, gas/particle partitioning, cancer risks, sources, and atmospheric transport of PCDD/Fs in a suburban area of Bursa, Türkiye
No full textPolychlorinated dibenzo-p-dioxins/furans (PCDD/Fs) are a very high-priority air pollutant group as they pose serious threats to human and environmental health. Most of the PCDD/F research studies have been carried out in urban and industrial areas where these pollutants are expected to be in high concentrations. There are few studies conducted in suburban areas worldwide, especially in T & uuml;rkiye. In this study, a sampling campaign covering 12 months (June 2022-June 2023) was conducted in a suburban area in Bursa, T & uuml;rkiye, to address this gap. The total average concentration was found to be 22.6 +/- 3.21 fg I-TEQ/m(3). This value was found to be comparable to the results reported for suburban and rural areas worldwide. The influence of the seasonal effect on concentrations was seen as a strong negative correlation (r = -0.84, p Li-Ma-Yang > Junge-Pankow approximate to pp-LFER > QSPR > mp-pp-LFER. Principal Component Analysis (PCA) showed that the main pollutant source in the region is traffic emissions. Back trajectory analysis indicated that air masses were transported to the sampling point from the organized industrial zones. Calculated cancer risk values revealed that there would be no significant risk due to inhalation of PCDD/Fs in the area
Does the onset of psoriasis in childhood or adulthood affect cardiovascular comorbidity?
No full textPsoriasis is a chronic, immune-mediated inflammatory disease with a prevalence of 2-3% in the general population and 0.7-1.2% among children in Western countries. It is often associated with comorbidities, particularly cardiovascular and metabolic diseases. This study aims to investigate the correlation between the onset of psoriasis during childhood (COP) and the prevalence of cardiovascular and metabolic comorbidities in adulthood, focusing on patients aged 30-50 years.A cross-sectional, multicenter study was conducted involving 1922 psoriasis patients from 12 centers across Turkey. Data collected included demographic information, disease characteristics, cardiovascular and metabolic comorbidities, laboratory parameters, and treatment history. Metabolic syndrome (MetS) was diagnosed based on established criteria, and logistic regression analysis was used to identify factors associated with comorbidities.Among the patients, 34.5% had the onset of psoriasis before the age of 18. The average duration of the disease was 28.28±53.42 years. The prevalence and age of onset of MetS were similar in both COP and AOP groups. Although the onset age of obesity was earlier in COP patients, no direct connection between the onset of psoriasis and obesity prevalence was established. Total cholesterol, LDL-cholesterol, and HOMA-IR levels were higher in the AOP group. The use of systemic and biological treatments was significantly higher in COP patients, with earlier initiation of biological treatments.The prevalence and age of onset of MetS were similar in COP and AOP patients. The onset age of obesity was earlier in COP patients, emphasizing the importance of weight management in pediatric psoriasis. Early and aggressive treatment targeting systemic inflammation may improve long-term outcomes by reducing comorbidities in psoriatic patients. This study highlights the need for a comprehensive treatment approach addressing both skin symptoms and associated systemic conditions
Design and development of polypropylene based, fully recyclable automotive door panel upholstery fabrics
No full textÜretim ve malzeme teknolojilerindeki hızlı ilerlemeler, sanayi ve tüketici ihtiyaçlarını daha çevreci ve sürdürülebilir çözümler doğrultusunda yeniden şekillendirmektedir. Bu gelişmeler, çevresel kaygıların artmasına ve doğaya olan olumsuz etkilerin azaltılması için yenilikçi yaklaşımların benimsenmesine neden olmaktadır. Geri dönüşüm ve geri dönüştürülmüş hammaddelerin üretim süreçlerine entegre edilmesi, çevre dostu çözümler arasında önemli bir yer tutmaktadır. Geri dönüşüm teknolojilerindeki ilerlemeler, bu malzemelerin kalitesini artırarak daha nitelikli ürünlerin üretilmesine olanak tanırken, doğal kaynaklara olan bağımlılığı azaltarak küresel ekonomiye katkıda bulunmaktadır. Otomotiv endüstrisi de geri dönüştürülebilir malzemelerin kullanımını teşvik eden bu dönüşümden etkilenmektedir. Modern araçlarda kullanılan termoplastik malzemeler, geri dönüşüm için uygun özelliklere sahip olup, ürün ömürleri sonunda yeniden değerlendirilebilmektedir. Ancak, bu malzemelerin çeşitliliği, etkili bir ayrıştırma süreci gerektirmektedir. Bu tez çalışmasında, otomotiv kapı panel kumaşlarının tamamen geri dönüştürülebilir yapıdaki polipropilen (PP) malzemelerle üretilmesi hedeflenmiştir. Araştırmalar sonucunda, alternatif malzemeler geliştirilmiş ve bu malzemelerden üretilen nihai ürünlerin otomotiv standartlarına uygunluğu test edilmiştir. Ürünün tüm bileşenlerinde tek bir termoplastik polimerin (PP) kullanımı sayesinde, üretim sırasında oluşan firelerin ve kullanım ömrünü tamamlamış malzemelerin kolayca geri dönüştürülebilmesi sağlanabilecektir. Bu çalışma, otomotiv sektöründe sürdürülebilir ve çevre dostu üretim yaklaşımlarının benimsenmesi açısından önemli bir adım olarak değerlendirilmektedir.Rapid advances in production and material technologies are reshaping industrial and consumer needs towards more environmentally friendly and sustainable solutions. These developments are causing environmental concerns to increase and innovative approaches to be adopted to reduce negative impacts on nature. Recycling and integrating recycled raw materials into production processes have an important place among environmentally friendly solutions. Advances in recycling technologies increase the quality of these materials, allowing for the production of more qualified products, while contributing to the global economy by reducing dependence on natural resources. The automotive industry is also influenced by this transformation, which encourages the use of recyclable materials. Modern vehicles widely utilize thermoplastic materials that are suitable for recycling, allowing these components to be reused at the end of their life cycles. However, the diversity of these materials requires an effective sorting process for efficient recycling. This thesis aims to produce automotive door-panel fabrics with fully recyclable polypropylene (PP) materials. As a result of the research, alternative materials have been developed and the conformity of the final products produced from these materials to automotive standards has been tested. Thanks to the use of a single thermoplastic polymer (PP) in all components of the product, it will be possible to easily recycle the wastes that occur during production and the materials that have reached the end of their service life. This study is considered as an important step in terms of adopting sustainable and environmentally friendly production approaches in the automotive sector
Sex specific effects of ketamine, but not other glutamate receptor modulators, on ethanol self-administration and reinstatement of ethanol seeking in rats
No full textRationale
Alcohol use and major depressive disorder are frequently comorbid, with individuals diagnosed with a substance use disorder being nearly three times as likely to have major depression. Poor treatment responses are found for both disorders and are further complicated when they co-occur, underscoring the need for better therapies. One potential candidate is ketamine, which has been shown to have rapid and long-lasting effects in individuals with treatment-resistant depression and, in some studies, reduces drinking in alcohol use disorder. However, though women are more likely to have this comorbidity, few studies have examined sex-specific effects of ketamine on alcohol drinking, nor have studies assessed the potential for ketamine to reduce reinstatement of alcohol seeking.
Objectives
The primary goal of the present studies was to determine the effects of ketamine on alcohol-motivated behaviors in male and female rats, including in a model of stress + cue-induced reinstatement of alcohol seeking using yohimbine (YOH).
Results
We found a selective reduction in alcohol self-administration and YOH + cue-induced reinstatement in females, but not males at a dose of 10 mg/kg ketamine. However, the same dose of ketamine was effective in reducing YOH + cue-induced reinstatement of saccharin seeking in both sexes. In addition, a different NMDAR antagonist, memantine, was effective in reducing alcohol seeking in both sexes, while the ketamine metabolite hydroxynorketamine (HNK) had no effects.
Conclusions
In summary, these data suggest that antagonism of NMDARs may be effective in reducing stress-related alcohol seeking, but that ketamine has unique properties that lead to female-specific effects on alcohol seeking.Version of Recor
