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关键词： Machinery and Machine Elements   Mechanical Engineering   History of Technology   History of Science  

ISBN: (数字)9783031811487 ISBN: (纸本)9783031811470;9783031811500

摘要： This book offers a description of the evolution of cams and their uses from the Middle Ages to the present day, highlighting their contribution to the development of technology. Usually, in the history of technology the diverse types of machines are taken into account, but the importance of cams is not emphasized, which are often fundamental for the operation of such machines. In this book the focus is instead on cams, understood as important, and often essential, components of machines that have had significant importance in the development of technology. It treats technical aspects at a level easily accessible even to non-experts in mechanics and the various applications are illustrated with many figures. The book serves as a reference work for those interested in both the history of technology and machines in general, and it helps them deal with certain mechanical problems, even starting from solutions already obtained with cams and, perhaps, overcoming them with others suggested by current developments in technology.

关键词： Chemistry   industrial chemistry  

ISBN: (数字)9781394175017 ISBN: (纸本)9781394174492

摘要： Discover how innovative nanotechnology can turn waste into opportunity, offering insights and strategies to create a greener, more eco-friendly textile industry. This book investigates nanotechnology-assisted sustainable solutions and their potential to transform waste into opportunity by fostering innovative designs and in-depth knowledge of sustainable waste management and nanotechnology applications. Divided into four comprehensive parts, comprising 16 chapters, Nanotechnology Assisted Recycling of Textile Waste , provides insights into the potential of nanotechnology in revolutionizing textile recycling and shaping the future of sustainable textiles. Part I sets the stage with an insightful overview of textile waste and management, exploring the conceptual dimensions and challenges in handling and organizing textile waste. It also describes the innovative realm of textile recycling. In Part II, the spotlight shines on comprehensive, sustainable, and productive recycling of waste using nanotechnology. Here, readers are invited to explore the transformative contributions of nanotechnology in shaping sustainable textile design and characterizing functional properties of novel recycled nano-textiles. Future perspectives of nanotechnology in textile applications, particularly concerning waste recycling, are also examined. Part III explores deeper into the advanced application of recycled and nano-assisted novel textiles generated through waste. From sports textiles to technical textiles, this section explores the diverse applications of recycled waste, bolstered by nano-engineered innovations. Finally, Part IV addresses the critical aspects of quality control and regulatory compliance in the realm of advanced nano-textile materials through an exploration of global legislation, schemes, and standards. Readers will find in this book: research findings and innovative approaches to cope with the challenges and issues of textile waste; systematic and scientific knowledge

关键词： vaccinia virus   poxvirus   mTORC1   CAD   pyrimidine   glutamine   asparagine   nutrition   metabolism   nutrient stress  

摘要： The molecular mechanisms by which vaccinia virus (VACV the prototypical member of the poxviridae family, reprograms host cell metabolism remain largely unexplored. Additionally, cells sense and respond to fluctuating nutrient availability, thereby modulating metabolic pathways to ensure cellular homeostasis. Understanding how VACV modulates metabolic pathways in response to nutrient signals is crucial for understanding viral replication mechanisms, with the potential for developing antiviral therapies. In this study, we establish the importance of de novo pyrimidine synthesis during VACV infection. We report the significance of vaccinia growth factor (VGF a viral early protein and a homolog of cellular epidermal growth factor (EGF in enabling VACV to phosphorylate the key enzyme CAD of the de novo pyrimidine pathway at serine 1859, a site known to positively regulate CAD activity. Although nutrient-poor conditions typically inhibit mTORC1 activation, VACV activates CAD via the mTORC1-S6K1 signaling axis in a VGF-dependent manner, especially upon glutamine and asparagine limitation. However, unlike its cellular homolog EGF, the VGF peptide alone, in the absence of VACV infection, has minimal ability to activate CAD. This suggests the involvement of other viral factors yet to be identified. Our research provides a foundation for understanding the regulation of a significant metabolic pathway, de novo pyrimidine synthesis during VACV infection, shedding new light on viral regulation under distinct nutritional environments. This study not only has the potential to contribute to the advancement of antiviral treatments but also improve the development of VACV as an oncolytic agent and vaccine vector. IMPORTANCE Viruses often reprogram host cell metabolism to facilitate replication. How poxviruses, such as the prototype member, vaccinia virus (VACV modulate host cell metabolism is not well understood. Understanding how VACV affects these metabolic pathways is key to learni

关键词： Cancer   CAM   Diet   Men   Oncology  

摘要： BackgroundEach year, over 20,000 men are diagnosed with cancer in Norway, and approximately 150,000 men who have previously been diagnosed with cancer are currently alive. Many of these cancer survivors encounter a range of challenges, including fatigue, sexual dysfunction, urinary issues, and pain, all of which can significantly impact their quality of life. Consequently, a substantial number of men seek support beyond conventional healthcare. This study aims to investigate the motivations behind the use of Complementary and Alternative Medicine (CAM) and dietary changes/supplements in men with cancer in Norway, and further explore their communication with healthcare providers, self-reported effects and adverse effects, and the sources of information they rely on regarding these practices.MethodIn collaboration with the Norwegian Cancer Society (NCS we conducted an online cross-sectional study involving participants of their user panel who have current or past experiences with cancer (n = 706 of whom 218 identified as men. The study was conducted during the autumn of 2021, employing a modified cancer-specific version of the International Questionnaire to Measure Use of Complementary and Alternative Medicine (I-CAM-Q). A total of 153 men agreed to participate, yielding a response rate of 70%.ResultsA large proportion of the respondents used CAM (62% dietary supplements (65% and/or adjusted their diet (81%) to boost their immune systems and increase their quality of life. The dietary adjustments involved eating more fruits, vegetables, fish, and whole grains. Many participants also used relaxation techniques and visited CAM providers to enhance quality of life. Most participants reported better health outcomes as a result of these interventions. The Internet and healthcare professionals were the main source of information, although many did not disclose their dietary changes and CAM therapy use with healthcare professionals.ConclusionBy leveraging these insights, hea

关键词： Cardiovascular risk factors   Acute coronary syndrome   Percutaneous coronary intervention   Age  

摘要： BackgroundAcute coronary syndrome (ACS) patients without standard modifiable cardiovascular risk factors (SMuRFs) have a higher risk of early mortality. However, little is known about their long-term outcomes, especially for patients undergoing percutaneous coronary intervention (PCI). This study aims to explore the long-term outcomes and identify independent factors associated with adverse clinical outcomes in patients with ACS undergoing PCI without SMuRFs.MethodsThis study used data from Optimal antiPlatelet Therapy for Chinese patients with Coronary Artery Disease (OPT-CAD) registry study. Clinical characteristics and outcomes of patients with and without SMuRFs were examined. The primary outcomes were major adverse cardia-cerebrovascular events (MACCE). The long-term (5 years) outcomes were compared between the without and with SMuRFs group in such cohort. An exploratory Cox proportional hazards regression was performed to identify the independent demographic and clinical predictors of the adverse clinical outcomes in the SMuRFs-absent cohort.ResultsAmong 5688 patients with ACS undergoing PCI, 392 (6.9%) were in the absence of SMuRFs and 5296 (93.1%) were in the presence of SMuRFs. There were no significant differences in MACCE rates between the two cohorts (9.44% vs. 9.76%, log-rank P = 0.90). Cox proportional hazards regression indicated that age (HR, 1.06;95% CI, 1.03-1.10;P = 0.001) and thrombus lesions (HR, 2.58;95% CI, 1.24-5.40;P = 0.011) were independently associated with MACCE in the SMuRFs-absent cohort.ConclusionsAmong patients with ACS undergoing PCI, SMuRFs-absent patients had similar MACCE rates when compared with those with one or more SMuRFs at 5 years.This suggests that effective intervention strategies and updated risk assessment models are urgently needed in the SMuRFs-absent cohort.ConclusionsAmong patients with ACS undergoing PCI, SMuRFs-absent patients had similar MACCE rates when compared with those with one or more SMuRFs at 5 years.This

关键词： CHIP   complex PCI   contrast-induced nephropathy   CTO   CA-AKI   contrast-associated acute kidney injury   CAD   coronary artery disease   CKD   chronic kidney disease   CTCA   computed tomographic coronary angiography   CV   contrast volume   FCA   functional coronary angiography   eGFR   estimated glomerular filtration rate   IVUS   intravascular ultrasound   PCI   percutaneous coronary intervention   ULCPCI   ultra-low-contrast percutaneous coronary intervention  

摘要： Since its inception, percutaneous coronary intervention (PCI) has relied upon vessel opacification with iodinated contrast to plan, guide, and assess the results of the procedure. Yet revisiting this fundamental concept is important in contemporary PCI practice, especially in patients with high-risk clinical or anatomical profiles. In addition to decreasing the probability of acute kidney injury during PCI, limiting the volume of iodinated contrast allows the operator to perform more thorough interventions by relying on intracoronary imaging and physiology, ultimately contributing to more complete revascularization and improving the efficacy and durability of the intervention. Ultra-low-contrast PCI (ULCPCI) may thus be useful in performing PCI not only in patients with chronic renal dysfunction but also in those with multivessel coronary artery disease, impaired left ventricular function, and many other scenarios. The aim of this review is to highlight contemporary PCI scenarios in which a ULCPCI approach may be beneficial. The authors provide a structured approach to address the challenges faced by operators in transitioning from conventional contrast-based interventions to ULCPCI, with practical solutions that are accessible to most interventionalists. The reader will learn that ULCPCI is feasible in contemporary practice as a result of technological innovation, the implementation of dedicated skills, and redefining the role of angiography as the cornerstone of contemporary PCI.

关键词： Thermal cycle   Conventional resin cement   Self-adhesive resin cement   Shear bond strength   CAD/CAM ceramics  

摘要： Purpose The aim of this study was to compare the shear bond strengths of four distinct CAD/CAM restorative materials using conventional resin-based adhesive cement and self-adhesive resin cement. Materials and methods Specimens (14 mm x 18 mm x 2 mm) were obtained for each restorative material: IPS e.max CAD (Ivoclar Vivadent (LEICHTENSTEIN GC Cerasmart (GC-Corp. JAPAN Vita-Enamic (Vita-ZahnFabrik, GERMANY and Cerec Blocks (Dentsply Sirona, USA n = 12). Ceramic surfaces were applided with both conventional resin-based adhesive cement (LF GC-LinkFORCE, GC Corp., JAPAN) and self-adhesive resin cements (CO G-Cem One, GC Corp., JAPAN). The shear bond strength test of 96 specimens were calculated and other 96 specimens were measured this test following thermal cycles (10000 thermal cycles at 5-55 oC (SD Mechatronik THERMOCYCLR, Gmbh). Shear bond strength results were statistically analyzed by independent samples t test, one-way ANOVA, two-way ANOVA, four-way ANOVA and for one and all test Post Hoc Tukey HSD test. Results After thermal cycles, a significant difference was observed between the shear bond strength of LF and CO cements to all ceramics except IPS e.max CAD ceramic (p < 0.05). After thermal cycling, LF cement had the strongest shear bond strength values with GC Cerasmart and the weakest bond values with Vita Enamic. CO cement had the strongest shear bond values with Cerec Blocks ceramics and the weakest bond values with GC Cerasmart. Cohesive type fractures were the most prevalent and adhesive type fractures were the least frequent both before and after thermal cycle. The type of material had a significant effect on the type of fracture after thermal cycle application (p < 0.05). Conclusions Thermal cycle application caused a decrease in the shear bond strength values of two kind of resin cements to all ceramics. It can be concluded that self-adhesive composite resin cement (G-CemONE) are suitable for leucite-reinforced glass-ceramic and lithium disilicate cer

摘要： Background Fractional flow reserve derived from coronary computed tomography angiography (FFR CT), Quantitative flow ratio (QFR), and Murray law-based quantitative flow ratio (μQFR) are non-invasive tools for diagnosing obstructive CAD. Methods Th...

关键词： Endocrown restoration   CAD/CAM   Fracture resistance   Fiber reinforced composite  

摘要： ObjectivesThe aim of this study was to evaluate the fracture resistance of endocrowns made of experimental short fiber-reinforced CAD/CAM block (SFRC CAD) in comparison with different commercial CAD/CAM materials. Materials and methodsIn this study, 60 sound mandibular molar teeth with similar occlusal sizes (+/- 1 mm) were used. Standard preparations simulating an endocrown cavity were prepared and the teeth were divided into four groups randomly. After the digital photoimpression of the prepared cavities using a dental intraoral scanner (CEREC the restorations were designed (4 mm high) and milled using IPS e.max, Cerasmart 270, Katana Avencia and SFRC CAD blocks (n = 15/per group). Restorations were cemented with self-adhesive dual-cure resin cement (G-Cem One). The specimens were immersed in a 37 degrees C water bath within the chewing simulator. Following cyclic fatigue aging for 1.000.000 cycles (Fmax=150 N a quasi-static load was applied using a universal testing machine at a speed of 1 mm/min. Fractography analysis was conducted using optical microscopy. ResultsAccording to the data obtained, there are statistically significant differences in fracture resistance values between different CAD/CAM materials (p < 0.05). The highest values were observed in the experimental SFRC CAD group (3025 N while the lowest values were observed in the IPS e.max group (2295 N). ConclusionsThe type of CAD/CAM restorative material influences the fracture resistance of endocrowns. SFRC CAD blocks could potentially serve as an alternative material for endocrown restorations in the future. Clinical relevanceEndocrowns fabricated from SFRC CAD blocks have demonstrated promising fracture behavior, suggesting their suitability for clinical testing.