Improved Rejection Penalty Algorithm with Multiprocessor Rejection Technique

This paper deals with multiprocessor scheduling with rejection technique where each job is provided with processing time and a given penalty cost. If the job satisfies the acceptance condition, it will schedule in the least loaded identical parallel machine else job is rejected. In this way its penalty cost is calculated. Our objective is to minimize the makespan of the scheduled job and to minimize the sum of the penalties of rejected jobs. We have merged ‘CHOOSE ‘and ‘REJECTION PENALTY’ algorithm to reduce the sum of penalties cost and makespan. Our proposed ‘Improved Reject penalty algorithm’ reduce competitive ratio, which in turn enhances the efficiency of the on-line algorithm. By applying our new on-line technique, we got the lower bound of our algorithm is is 1.286 which is far better from the existing algorithms whose competitive ratio is at 1.819. In our approach we have consider non-preemption scheduling technique

Three-dimensional electrospun nanofibrous scaffolds to fabricate in vitro model for liver diseases

Liver extracellular matrix, which has random fibrous network structure, can be closely mimicked by the electrospun fibrous scaffolds. Thus, electrospinning is a promising technology to develop scaffolds for liver tissue engineering. However, the closely packed fibrous mat obtained by the conventional electrospinning process restricts cellular infiltration, thus act like a two-dimensional cell culture model which is different from the in vivo three-dimensional microenvironment. In this study, an interdisciplinary approach was applied to construct a three-dimensional liver tissue mimicking scaffold by using the knowledge of material science and molecular biology. A newly optimized wet electrospinning process was applied to prepare three-dimensional scaffolds with random fibrous network structure. The three-dimensional random electrospun fibers mimic the physical microenvironment, whereas the extracellular matrix proteins grafted on the fiber surface by chemisorption process mimics the chemical microenvironment for the human liver cells. Collagen-I and fibronectin, which are two essential liver extracellular matrix proteins were used to modify the fiber surface. The initial findings suggested that collagen-I modified 3D wet electrospun scaffolds were superior compared to both fibronectin modified scaffold and gold standard sandwich culture in maintaining functions of primary human hepatocytes in vitro. Thus, collagen-I modified 3D electrospun scaffold was used for co-culture of primary human hepatocytes with human hepatic stellate cells to establish the optimum ratio of these two liver cells in the in vitro culture. The ratio was optimized by studying the long-term functional maintenance of primary human hepatocytes. The distinct role of collagen-I and fibronectin for in vitro maintenance of primary human hepatocytes were analyzed and these findings leads to further exploration of the combined effect of these two-essential ECM proteins for the culture of human liver cells in vitro. A series of different ratios of collagen-I to fibronectin were used to chemisorb the electrospun scaffolds. The protein amounts were optimized based on total protein absorbed and the homogeneous distribution of both the proteins on the scaffold surface. Improved protein distribution on the fiber surface was found to enhance functional maintenance of human hepatocytes on 3D electrospun fibrous scaffolds. The findings suggested that cellular microenvironment controls translational and transcriptional properties of the liver cells. The optimized 3D electrospun fibrous scaffolds with optimum ratio of human primary hepatocytes and human hepatic stellate cells were used to fabricate an alcoholic liver disease model. The proposed model was analyzed at different dosage of alcohol under different scaffold conditions. The effect of alcohol was found to be more prominent on the cells cultured on the electrospun fibrous scaffolds modified with both collagen-I and fibronectin when compared to the single protein modified scaffolds, unmodified scaffolds and the gold standard sandwich culture. This ECM modified electrospun fibrous scaffolds with human liver cells can be used as an engineered liver tissue for studying the effect of different toxins, fibrosis causing elements or dose dependent study of antifibrotic drugs.Doctor of Philosoph

Extracting road maps from high-resolution satellite imagery using refined DSE-LinkNet

Road detection and extraction have gained momentum in recent past years with crucial applications such as urban planning, autonomous driving, automated map update, providing aid to rescue missions, etc. The current methodologies generate the disconnected road segments, cause boundary loss, and also they are incapable of handling the imbalanced class distribution problems. In this paper, we propose a fully convolutional architecture, named as refined DSE-LinkNet, to extract the connected and precise road maps. We use a pre-trained encoder by combining the layers of the two very efficient and light-weight CNN models: DenseNet and SE-Net that makes the proposed model more expressive with faster convergence. We introduce a new module, Fusion block, in our architecture that enhances its precise localisation as well as classification ability by capturing multilevel as well as multiscale features. To address the imbalanced class distribution problem, a new aggregate loss function is proposed by integrating binary cross-entropy, Jaccard coefficient, and Lovasz sigmoid loss functions. The experiments are performed on a publicly available dataset, DeepGlobe Road Extraction Challenge 2018, to show its efficacy over the D-LinkNet, winner of DeepGlobe Challenge 2018, by achieving IoU of 0.69 with lesser number of parameters and better computational complexity

Synthesis and characterization of site selective photo-crosslinkable glycidyl methacrylate functionalized gelatin-based 3D hydrogel scaffold for liver tissue engineering

The presented work outlined the development of a new biocompatible hydrogel material that has potential applications in soft tissue engineering. As a proof of concept, human hepatocytes were used to demonstrate the suitability of this material in providing conducive environment for cellular growth and functional development. Herein, a detailed synthesis of novel gelatin derivatives - photo-crosslinkable glycidyl methacrylate (GMA) functionalized gelatins (Gelatin-GMA), and preparation of three-dimensional (3D) hydrogel scaffolds for the encapsulated Huh-7.5 cells is reported. The Gelatin-GMA biopolymers were synthesized at two different pH values of 3.5 (acidic) and 10.5 (basic) where two different photo-crosslinkable polymers were formed utilizing -COOH & -OH groups in acidic pH, and -NH2 & -OH groups in basic pH. The hydrogels were prepared using an initiator (Irgacure I2959) in the presence of UV light. The Gelatin-GMA biopolymers were characterized using spectroscopic studies which confirmed the successful preparation of the polymer derivatives. Rheological measurement was carried out to characterize the mechanical properties and derive the mesh sizes of the 3D hydrogels. Subsequently, detailed in vitro hepatocyte compatibility and functionality studies were performed in the 3D cell seeded hydrogel platform. The 3D hydrogel design with larger mesh sizes utilizes the advantage of the excellent diffusion properties of porous platform, and enhanced cell-growth was observed, which in turn elicited favorable Huh-7.5 response. The hydrogels led to improved cellular functions such as differentiation, viability and proliferation. Overall, it showed that the Gelatin-GMA based hydrogels presented better results compared to control sample (GelMA) because of the higher mesh sizes in Gelatin-GMA based hydrogels. Additionally, the functional group studies of the two Gelatin-GMA samples revealed that the cell functionalities are almost unaffected even after the tripeptide - Arg-Gly-Asp (RGD) in Gelatin-GMA synthesized at pH 3.5 is no longer completely available.Ministry of Education (MOE)The authors acknowledge the NTU-Northwestern Institute for Nanomedicine (NNIN) and MOE Tier 1 (RG 46/18) for the financial support

Correlation Between Serum Ferritin Levels and Echocardiographic Changes in Children with Beta-thalassaemia Major- A Cross-sectional Analytical Study

Introduction: Heart failure secondary to iron overload is the leading cause of mortality in patients with beta-thalassaemia major. Prevention of myocardial siderosis is a key step to reducing the rate of mortality in thalassaemia children. Aim: To study the correlation between serum ferritin levels and echocardiography parameters in children with beta-thalassaemia major. Materials and Methods: This cross-sectional analytical study was conducted in the Department of Paediatrics, RG Kar Medical College and Hospital, Kolkata, India from March, 2020 to July, 2021. A total of 85 beta-thalassaemia major children aged between 2-12 years without having any active infections or congenital heart diseases, were included in this study. Blood samples were obtained from these children for serum ferritin level assessment and echocardiography was performed to evaluate their cardiac function. Data were statistically analysed using the Chi-square test. Results: The mean age of patients was 7.24±2.76 years and the age range was 1-12 years. Mean serum ferritin levels in the study was 1938.67±992.57 and more than three-fourth of our population had serum ferritin levels more than 1000 ng/mL. A 30% of present study population had abnormal echo findings. A significant correlation was noted between serum ferritin levels and echo parameters like Fractional Shortening (FS), Deceleration Time (DT), Early and Late Ratio (E/A ), Left Ventricular Mass (LV Mass). But negative correlation was found between serum ferritin levels and Ejection Fraction (EF). Conclusion: The present study concluded that due to the significant correlation between serum ferritin levels and echocardiographic parameters, it is beneficial to conduct echocardiography in all patients of beta thalassaemia major in their first decade to gain a better understanding of cardiac function

Ultrasonic Implantation and Imaging of Sound-Sensitive Theranostic Agents for the Treatment of Arterial Inflammation

For site-specific diseases such as atherosclerosis, it is desirable to noninvasively and locally deliver therapeutics for extended periods of time. High-intensity focused ultrasound (HIFU) provides targeted drug delivery, yet remains unable to sustain delivery beyond the HIFU treatment time. Furthermore, methods to validate HIFU-enhanced drug delivery remain limited. In this study, we report on HIFU-targeted implantation of degradable drug-loaded sound-sensitive multicavity PLGA microparticles (mcPLGA MPs) as a theranostic agent for the treatment of arterial lesions. Once implanted into the targeted tissue, mcPLGA MPs eluted dexamethasone for several days, thereby reducing inflammatory markers linked to oxidized lipid uptake in a foam cell spheroid model. Furthermore, implanted mcPLGA MPs created hyperechoic regions on diagnostic ultrasound images, and thus noninvasively verified that the target region was treated with the theranostic agents. This novel and innovative multifunctional theranostic platform may serve as a promising candidate for noninvasive imaging and treatment for site-specific diseases such as atherosclerosis

Thermostable acidic protease production in Aspergillus terreus NCFT 4269.10 using chickling vetch peels

A newly isolated fungus, Aspergillus terreus NCFT4269.10, was employed in both solid state (SSF) and liquid static surface culture (LSSC) for the production of protease using different agro-residues. Among different substrates appraised, chickling vetch peels (CVP) supported the enhanced production of protease both at LSSC and SSF (499.99 ± 11 U/ml; 5266.8 ± 202.5 U/gds, respectively). In the presence of peptone (1%, w/v), leucine (5 mM/100 ml), Fe2+ (1 mM) and riboflavin (10 mg/100 ml) with a medium pH of 5.0 incubated at 30 °C for 96 h, 3-fold higher protease production was achieved in LSSC compared with control. Fermentation kinetics studies revealed that the highest specific growth rate of A. terreus was observed in fermentation medium supplemented with riboflavin (10 mg/100 ml), i.e., 256.45 mg l−1 h−1. The growth-associated coefficient of enzyme production (α) by A. terreus was maximal when protease was produced using Fe2+. Further, the protease was purified to electrophoretic homogeneity and its molecular mass was determined as 23.8 kDa. The present strain suggests the potential utilization of inexpensive agro-residues (CVP) as medium components for the efficient industrial production using LSSC

Nanofibrous PLGA electrospun scaffolds modified with type I collagen influence hepatocyte function and support viability in vitro

A major challenge of maintaining primary hepatocytes in vitro is progressive loss of hepatocyte-specific functions, such as protein synthesis and cytochrome P450 (CYP450) catalytic activity. We developed a three-dimensional (3D) nanofibrous scaffold made from poly(l-lactide-co-glycolide) (PLGA) polymer using a newly optimized wet electrospinning technique that resulted in a highly porous structure that accommodated inclusion of primary human hepatocytes. Extracellular matrix (ECM) proteins (type I collagen or fibronectin) at varying concentrations were chemically linked to electrospun PLGA using amine coupling to develop an in vitro culture system containing the minimal essential ECM components of the liver micro-environment that preserve hepatocyte function in vitro. Cell-laden nanofiber scaffolds were tested in vitro to maintain hepatocyte function over a two-week period. Incorporation of type I collagen onto PLGA scaffolds (PLGA-Chigh: 100 µg/mL) led to 10-fold greater albumin secretion, 4-fold higher urea synthesis, and elevated transcription of hepatocyte-specific CYP450 genes (CYP3A4, 3.5-fold increase and CYP2C9, 3-fold increase) in primary human hepatocytes compared to the same cells grown within unmodified PLGA scaffolds over two weeks. These indices, measured using collagen-bonded scaffolds, were also higher than scaffolds coupled to fibronectin or an ECM control sandwich culture composed of type I collagen and Matrigel. Induction of CYP2C9 activity was also higher in these same type I collagen PLGA scaffolds compared to other ECM-modified or unmodified PLGA constructs and was equivalent to the ECM control at 7 days. Together, we demonstrate a minimalist ECM-based 3D synthetic scaffold that accommodates primary human hepatocyte inclusion into the matrix, maintains long-term in vitro survival and stimulates function, which can be attributed to coupling of type I collagen.Accepted versio

Anti-inflammatory potential of simvastatin loaded nanoliposomes in 2D and 3D foam cell models

Atherosclerosis is a multifactorial disease triggered and sustained by risk factors such as high cholesterol, high blood pressure and unhealthy lifestyle. Inflammation plays a pivotal role in atherosclerosis pathogenesis. In this study, we developed a simvastatin (STAT) loaded nanoliposomal formulation (LIPOSTAT) which can deliver the drug into atherosclerotic plaque when administered intravenously. This formulation is easily prepared, stable, and biocompatible with minimal burst release for effective drug delivery. 2D and 3D in vitro models were examined towards anti-inflammatory effects of STAT, both free and in combination with liposomes. LIPOSTAT induced greater cholesterol efflux in the 2D foam cells and significantly reduced inflammation in both 2D and 3D models. LIPOSTAT alleviated inflammation by reducing the secretion of early and late phase pro-inflammatory cytokines, monocyte adherence marker, and lipid accumulation cytokines. Additionally, the 3D foam cell spheroid model is a convenient and practical approach in testing various anti-atherosclerotic drugs without the need for human tissue.Accepted versionThis study was supported by the NTU–Northwestern Institute for Nanomedicine (04INS000156C150)