Human Adipocytes and the Composition of Plasma Lipoproteins: Linking Obesity with Type 2 Diabetes and Cardiovascular Disease

Maintaining energy homeostasis is one of the fundamental tasks of the body that has to be performed, and it is largely achieved through the control of blood glucose level. Thus normoglycemia is regulated through proper energy delivery to the energy-demanding tissues or storage in the adipose tissue through the lipoprotein compartment. The processes constitute a multitude of tightly regulated and highly tuned mechanisms, which is only partly understood and involved in all tissues. Nevertheless, the adipose tissue and in particular adipocytes together with the skeletal muscle and liver seems to be the most important organs for dealing with challenges to keep body energy and energy metabolic system in homeostasis. Although through most of mankind’s history, lack of energy was the main challenge in current societies excess intake of calories and especially fats and sugars as well as their main manifestation, and hyperglycemia-related diseases has become a serious problem. The situation is compounded by the increase of sedentary life-styles and the use of high level of tobacco (Cabrera de et al., 2007; Oh et al., 2005). Currently, 65% of the global population lives in countries where obesity kills more people than malnutrition (WHO - Global strategy on diet, physical activity and health, 2010). The metabolic diseases include obesity-induced metabolic syndrome, lipodystrophia, and type 2 diabetes mellitus (T2DM) represent an ever increasing challenge to health care. A guiding principle of this thesis is that many aspects of these diseases can be better understood through insight into the energy metabolism of the adipocytes as well as improved knowledge of the adipocytes and their production. Furthermore, I shall argue that the lipoprotein compartment is not only a mediator between the adipose compartment and the periphery with respect to the transport of energy-rich hydrophobic molecules, but also is an important transport modality for adipocyte-generated endrocrinological signals

Leveraging Deep Learning Techniques on Collaborative Filtering Recommender Systems

With the exponentially increasing volume of online data, searching and finding required information have become an extensive and time-consuming task. Recommender Systems as a subclass of information retrieval and decision support systems by providing personalized suggestions helping users access what they need more efficiently. Among the different techniques for building a recommender system, Collaborative Filtering (CF) is the most popular and widespread approach. However, cold start and data sparsity are the fundamental challenges ahead of implementing an effective CF-based recommender. Recent successful developments in enhancing and implementing deep learning architectures motivated many studies to propose deep learning-based solutions for solving the recommenders' weak points. In this research, unlike the past similar works about using deep learning architectures in recommender systems that covered different techniques generally, we specifically provide a comprehensive review of deep learning-based collaborative filtering recommender systems. This in-depth filtering gives a clear overview of the level of popularity, gaps, and ignored areas on leveraging deep learning techniques to build CF-based systems as the most influential recommenders.Comment: 24 pages, 14 figure

Urban design, Socialization, and quality of life 1

Abstract: Architecture as a discipline is essentially integrative: connecting past, present and future, drawing on art, science and the social sciences, balancing qualitative with quantitative factors. Good architecture and urban design contribute to making cities both functional and attractive to residents and visitors. While architecture is about the design of buildings, urban design is about the relationships between the buildings, the roads and spaces that they front, and the people who make use of them. The outstanding building projects are those that are not only visually stimulating, but are also sensitive and respectful of their surrounding developments and environment. A well-designed city takes into consideration this important relationship between buildings and the beauty of the city as a whole. Socialization is the process that prepares humans to function in social life. It should be re-iterated here that socialization is culturally relative -people in different cultures are socialized differently. The process of socializing or sociability in a city means acquiring the model of style life of that city. The process of socializing includes every daily activities of citizens' life. People have mutual relationship in this place and actualize it through presenting the municipal cultural and social activities and resolving the needs of each other. The municipal cultural and social realm has to develop the way of acquiring the necessary life skills gradually among the citizens. These patterns can be taught through an effective and mutual relationship, this education should be presented to acquire the necessary abilities considering the cultural values and norms of a society continually and constantly

Effects of TPU on the mechanical properties, fracture toughness, morphology, and thermal analysis of 3D‐printed ABS‐TPU blends by FDM

In this paper, blends of ABS-TPU with two different weight percentages of TPU were prepared using fused deposition modeling technology. The effect of adding TPU on the fracture toughness of ABS and mechanical properties was comprehensively studied. Tensile, compression, fracture toughness, and shear tests were conducted on the 3D-printed samples. Thermal and microstructural analyses were performed using dynamic mechanical thermal analysis (DMTA), and scanning electron microscope (SEM). The DMTA results showed that adding TPU decreased the storage modulus and the glass transition temperature of ABS, as well as its peak intensity. The mechanical test results showed that adding TPU decreased the strength but increased the formability and elongation of the samples. Fracture tests showed that the addition of TPU decreased the maximum force needed for a crack to initiate. The force required for crack initiation decreased from 568.4 N for neat ABS to 335.3 N for ABS80 and 123.2 N for ABS60. The ABS60 blend exhibited the highest strength against crack growth, indicating that TPU can change the behavior of ABS from brittle to ductile. Shear test results and SEM images also showed good adhesion strength between the printed samples for all three specimens, indicating their good printability. Adding TPU resulted in a reduction in the size and number of voids and holes between the printed layers

4D printing-encapsulated polycaprolactone–thermoplastic polyurethane with high shape memory performances

There are a few shape memory polymers (SMPs) like polylactic acid (PLA) and polyurethane (PU) that are 4D printable, and other SMPs must be synthesized with a complicated chemical lab effort. Herein, considering dual-material extrusion printing and microscopic mechanism behind shape memory effect (SME), bilayer-encapsulated polycaprolactone (PCL)–thermoplastic polyurethane (TPU) shape memory composite structures are 4D printed for the first time. The SME performance is investigated by assessing fixity, shape recovery, stress recovery, and stress relaxation under bending and compression loading modes. PCL, TPU, and melting temperature of PCL play the role of switching phase, net point, and transition temperature, respectively. Due to the destruction and dripping of molten PCL in contact with water, PCL is encapsulated by TPU. Encapsulation successfully solves the challenge of bonding/interface between printed layers, and the results show that the SME performance of the encapsulated structures is higher than bilayer PCL–TPU one's. Experiments reveal that maximum stress recovery in 4D-printed composites remains constant over time. This is a great achievement compared to the previous extrusion-based SMP structures that have great weakness in stress relaxation due to weak and low crystalline fractions and the unraveling of molecular entanglements in semicrystalline and amorphous thermoplastic SMPs, respectively

Development of pure poly vinyl chloride (PVC) with excellent 3D printability and macro‐ and micro‐structural properties

Unmodified polyvinyl chloride (PVC) has low thermal stability and high hardness. Therefore, using plasticizers as well as thermal stabilizers is inevitable, while it causes serious environmental and health issues. In this work, for the first time, pure food-grade PVC with potential biomedical applications is processed and 3D printed. Samples are successfully 3D printed using different printing parameters, including velocity, raster angle, nozzle diameter, and layer thickness, and their mechanical properties are investigated in compression, bending, and tension modes. Scanning electron microscopy is also used to evaluate the bonding and microstructure of the printed layers. Among the mentioned printing parameters, raster angle and printing velocity influence the mechanical properties significantly, whereas the layer thickness and nozzle diameter has a little effect. Images from scanning electron microscopy also reveal that printing velocity greatly affects the final part's quality regarding defective voids and rasters’ bonding. The maximum tensile strength of 88.55 MPa is achieved, which implies the superiority of 3D-printed PVC mechanical properties compared to other commercial filaments. This study opens an avenue to additively manufacture PVC that is the second most-consumed polymer with cost-effective and high-strength features

4D printing of polyvinyl chloride (PVC): a detailed analysis of microstructure, programming, and shape memory performance

In this research, polyvinyl chloride (PVC) with excellent shape-memory effects is 4D printed via fused deposition modeling (FDM) technology. An experimental procedure for successful 3D printing of lab-made filament from PVC granules is introduced. Macro- and microstructural features of 3D printed PVC are investigated by means of wide-angle X-ray scattering (WAXS), differential scanning calorimetry (DSC), and dynamic mechanical thermal analysis (DMTA) techniques. A promising shape-memory feature of PVC is hypothesized from the presence of small close imperfect thermodynamically stable crystallites as physical crosslinks, which are further reinforced by mesomorphs and possibly molecular entanglement. A detailed analysis of shape fixity and shape recovery performance of 3D printed PVC is carried out considering three programming scenarios of cold (Tg −45 °C), warm (Tg −15 °C), and hot (Tg +15 °C) and two load holding times of 0 s, and 600 s under three-point bending and compression modes. Extensive insightful discussions are presented, and in conclusion, shape-memory effects are promising, ranging from 83.24% to 100%. Due to the absence of similar results in the specialized literature, this paper is likely to fill a gap in the state-of-the-art shape-memory materials library for 4D printing, and provide pertinent results that are instrumental in the 3D printing of shape-memory PVC-based structures

A new strategy for achieving shape memory effects in 4D printed two-layer composite structures

In this study, a new strategy and design for achieving a shape memory effect (SME) and 4D printed two-layer composite structures is unveiled, thanks to fused deposition modeling (FDM) biomaterial printing of commercial filaments, which do not have an SME. We used ABS and PCL as two well-known thermoplastics, and TPU as elastomer filaments that were printed in a two-layer structure. The thermoplastic layer plays the role of constraint for the elastomeric layer. A rubber-to-glass transition of the thermoplastic layer acts as a switching phenomenon that provides the capability of stabilizing the temporary shape, as well as storing the deformation stress for the subsequent recovery of the permanent shape by phase changing the thermoplastic layer in the opposite direction. The results show that ABS–TPU had fixity and recovery ratios above 90%. The PCL–TPU composite structure also demonstrated complete recovery, but its fixity was 77.42%. The difference in the SME of the two composite structures is related to the transition for each thermoplastic and programming temperature. Additionally, in the early cycles, the shape-memory performance decreased, and in the fourth and fifth cycles, it almost stabilized. The scanning electron microscopy (SEM) photographs illustrated superior interfacial bonding and part integrity in the case of multi-material 3D printing