Synthesis and characterization of polyestermaleamides

Summary Polyestermaleamides have been synthesized from N,N-bisisomaleimide, p-aminophenol, iso-and tere-phthaloyl chlorides. Through ring-opening addition reaction, a bisphenolamide was first formed; it was then polycondensed with acid chlorides to produce Polyestermaleamides, with an ordered sequence. The polymers were fully characterized by elemental analysis, infrared and electronic spectra, solubility in various solvents as well as inherent viscosity measurements. Thermal behaviour of the polymers were determined by thermogravimetric analysis in nitrogen atmosphere.     

Analysis of a boundary layer flow over moving an exponentially stretching surface with variable viscosity and Prandtl number

Boundary layer flow phenomenons on a stretching sheet find numerous applications in industrial processes such as manufacture and extraction of rubber and polymer sheets. The current study focuses on two‐dimensional water boundary layer flow on exponential stretching surface with a vertical plate for variable physical properties of fluid such as viscosity and Prandtl number. The Quasilinearization technique has been used on governing equations to transform nonlinear to linear equations and these equations are discretized by finite difference techniques to get numerical solutions. The effect of buoyancy parameters (λ), velocity ratio parameter () and streamwise coordinator (ξ) on velocity profiles (F), temperature profiles (θ), local skin‐friction coefficient (C_fx(Re_Lξexp(ξ)^)1/2) and the local Nusselt number (Nu_x(Re_Lξexp(ξ)^)?1/2) has been analyzed graphically based on numerical outcome. The magnitude of velocity profiles increases and temperature profile decreases approximately by 4% and 16% with increases the buoyancy parameter from λ = 1 to λ = 3 at = 0.5 and ξ = 1.0. The skinfriction and heat transfer coefficient increases approximately by 22% and 27% with an increase in ξ from 0.5 to 1.0 at fixed = 0.5 and λ = 1.0. The variations of velocity profiles and temperature profiles have more impact with as compared to ξ and λ. The benchmark studies were carried out to validate the current results with previously published work and found to be in excellent agreement.     

Polymaleamidehydrazides

Summary Some polymaleamidehydrazides were synthesized by the ring-opening polyaddition reaction between N,N-bisisomaleimide and diamines(piperazine, phenylenediamines, 4,4-diaminodiphenyl, 1,5-diaminonaphthalene, and 2,6-diaminoanthraquinone) in N-methyl-2-pyrrolidone (NMP) containing LiCl Characterization of the polymers was carried out by elemental analysis, solibility in various solvents, IR, UV-VIS, PMR spectra, TG and DSC as well as by inherent viscosity measurements. These polymers began to decompose around 250°C.     

Studies on certain new polymaleamidehydrazides

Three polymaleamidehydrazides have been synthesised by the ring-opening polyaddition of N,N′-bisisomaleimide with aromatic diamines (having methyl or methoxy ring substituents or flexible SO₂ groups between benzene rings) at room temperature. Thermogravimetry and mass spectrometry have been used in conjunction with infrared spectroscopy, inherent viscosity measurements, NMR and UV-visible spectroscopy to characterise these polymers.     

Synthesis and characterisation of new polymaleamides from N,N′-ethanedianilinebisisomaleimide with some aromatic diamines

Five polymaleamides have been synthesised by the ring-opening polyaddition of N,N′-ethanedianilinebisisomaleimide (EBIMI) with aromatic diamines (having methyl or methoxy ring substituents) at room temperature; EBIMI was synthesised from N,N′-ethanedianilinebismaleamic acid. Infrared, ¹³C NMR, and UV–visible spectroscopies, inherent viscosity measurements, thermogravimetry, differential scanning calorimetry and mass spectrometry have been used to characterise these polymers.     

Image registration-based brain tumor detection and segmentation using ANFIS classification approach

Abnormal cells in human brain lead to the development of tumors. Manual detection of this tumor region is a time-consuming process. Hence, this paper proposes an efficient and automated computer-aided methodology for brain tumor detection and segmentation using image registration technique and classification approaches. This proposed work consists of the following modules: image registration, contourlet transform, and feature extraction with feature normalization, classification, and segmentation. The extracted features are optimized using genetic algorithm, and then an adaptive neuro-fuzzy inference system classification approach is used to classify the features for the detection and segmentation of tumor regions in brain magnetic resonance imaging. A quantitative analysis is performed to evaluate the proposed methodology for brain tumor detection using sensitivity, specificity, segmentation accuracy, precision, and Dice similarity coefficient.     

Thermal Performance of an Air-Cooled Data Center With Raised-Floor and Non-Raised-Floor Configurations

In this paper, the thermal performances of an air-cooled data center with raised-floor and non-raised-floor configurations are compared with respect to the room and ceiling return strategies. The thermal performance of the data center is evaluated in terms of supply heat index, rack cooling index, total irreversible loss, and the number of racks with at least one server exceeding the maximum recommended and allowable inlet air temperature according to American Society of Heating, Refrigeration, and Air-Conditioning Engineers (ASHRAE) thermal guidelines. The numerical simulations are conducted providing an insight into the flow and temperature distributions, and thus giving a better understanding of the cooling issues. It is found that using a ceiling return strategy for the return of hot exhaust air to the computer room air conditioning units gives a better thermal performance of the data center, for both raised- and non-raised-floor strategy, as compared to the room return. The findings are then extended to a geometrically complex operational data center to improve its cooling effectiveness. The paper also highlights the drawback of using supply heat index alone as a performance metric.     

Genetic Variants and Tumor Immune Microenvironment: Clues for Targeted Therapies in Inflammatory Breast Cancer (IBC)

To better understand the etiology of inflammatory breast cancer (IBC) and identify potential therapies, we studied genomic alterations in IBC patients. Targeted, next-generation sequencing (NGS) was performed on cell-free DNA (cfDNA) (n = 33) and paired DNA from tumor tissues (n = 29) from 32 IBC patients. We confirmed complementarity between cfDNA and tumor tissue genetic profiles. We found a high incidence of germline variants in IBC patients that could be associated with an increased risk of developing the disease. Furthermore, 31% of IBC patients showed deficiencies in the homologous recombination repair (HRR) pathway (BRCA1, BRCA2, PALB2, RAD51C, ATM, BARD1) making them sensitive to poly (ADP-ribose) polymerase (PARP) inhibitors. We also characterized the tumor-infiltrating lymphocytes (TILs) in tumor tissue biopsies by studying several markers (CD4, CD8, FoxP3, CD20, PD-1, and PD-L1) through immunohistochemistry (IHC) staining. In 7 of 24 (29%) patients, tumor biopsies were positive for PD-L1 and PD-1 expression on TILs, making them sensitive to PD-1/PD-L1 blocking therapies. Our results provide a rationale for considering PARP inhibitors and PD-1/PDL1 blocking immunotherapy in qualifying IBC patients.     

Antibiotic resistance profiling and valorization of food waste streams to starter culture biomass and exopolysaccharides through fed-batch fermentations

Food Science and Biotechnology - The present study evaluated antibiotic resistance (ABR) in bacteria isolated from different food wastes viz., meat slaughterhouses, dairy and restaurants. About 120...