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This essay uses Freudian–Lacanian psychoanalytic theory to interpret Hassan Blasim’s short story “The Nightmares of Carlos Fuentes”. Blasim’s story depicts the psychological struggles of an Iraqi emigrant relating to his embattled sense of belonging in a Dutch society due to the recurrent nightmares of his “traumatic” past. It challenges his assimilationist fantasies. I develop Lacan’s idea of ontological lack as a structural susceptibility that is exacerbated by actual experiences of trauma to underline how racialized refugees from the war-torn global South are doubly vulnerable to experiencing subjective dehiscence between their efforts to forget past war traumas and the challenges of assimilating into (white) host nations. This essay uses Blasim’s story to illustrate a serious psychological issue experienced by racialized minority subjects in white/European host countries.

The effects of cross-sectional shape, fiber density, and porosity of flax, jute, okra, sisal, and wool fibrous assemblies on noise absorption coefficient have been investigated. The shape was described in terms of its shape factor and the depth of grooves on the fiber’s surface. The number of lobes on the surface of the fiber, which is attributed to intrinsic variability, was utilized to construct the governing equation of shape factors. The shape factor tends to increase as the number of lobes increases. Shapes such as hexalobal (jute), pentalobal (flax), tetralobal (okra), trilobal (sisal), and circular (wool) affected noise control performance. The technique for order performance by similarity to ideal solution (TOPSIS) was used to rank the fibers for noise control performance based on five attributes namely, cross-sectional area, shape eccentricity, shape factor, bulk density, and porosity for validation. The technique confirmed the rank of the absorption performance of the fiber measured by transfer matrix method in impedance tube (ISO 10,534–2). Okra rendered the best noise absorption for its multilobal shape, low density, and spatial arrangement. Wool having regular cross-sections resulted in much lower noise absorption performance.

The physico-mechanical characteristics of fibers extracted from seven dual-purpose flax (DPF) and two fiber flax (FF) varieties grown in India were investigated to determine their suitability for various textile and technical applications. The selected varieties were evaluated in terms of the plant’s phenotypic traits, maturity, fiber, and seed production. The flax fibers, after water retting, were examined for extent of retting, fiber mass loss, quantity, length, fineness, color, tenacity, and elongation. Fibers were characterized by thermogravimetric analysis (TGA), scanning electron microscopy (SEM), Fourier Transform Infrared spectroscopy (FTIR), and X-ray diffractometry (×RD). Despite significant differences in phenotypic attributes among the nine varieties, except fiber tenacity, the difference in fineness, length, and elongation was found to be negligible. Thermo-chemical properties of the fibers also showed similarity across the nine varieties.

The present study is an attempt to evaluate the potentiality of a specified variety of banana fiber (Musa domestica var. balbisiana) for textile use. Retting period for extraction of the newer variety was optimized as 28 days in water. The extracted fibers were found to have cellulose content (58.5%), hemicelluloses (13.1%), lignin (7.4%) along with high fat and waxes (1.2%) and moisture (13.1%). SEM of the retted fibers demonstrated it to be a multicellular having lumen in each cell making it porous in the structure having hexagonal fibrils running through the axis. Bleaching improved the cellulose content (65%) fineness, and length diameter ratio, from 915 to 1147. The tensile strength (34.86 cN/tex), elongation (2.4%) and initial modulus (1727.7 cN/tex) of the retted fiber was reduced after bleaching. One hundred percent banana yarn was not strong enough for subsequent mechanical processes. Banana fibers can be processable in long staple jute processing system on their blending with ramie fiber having banana fiber content about 50% to produce fine blend yarn (213 tex) of tenacity 15.71 cN/tex at spinning speed 3500 rpm. It can also be concluded that banana fiber, which is till now being wasted after harvesting of fruits, showed good potential for value-added textiles.

Effect of pore size and its distribution on the noise reduction coefficient of jute felt were studied through capillary flow porometer and impedance tube. The inter-criteria correlation method was used to optimize the type of jute felts to obtain noise reduction coefficient of 0.5. The porometry study of the needle punched jute felt suggested the gradient pore structure of felt due to presence of needling induced inverted cone of pores within fibrous mass. The jute felt with an areal density 796.5 g/m2 with mean pore diameter 60.32 µm offered optimum noise reduction coefficient of 0.5. The percentage weight of pore distribution in the range of 45≥ ∅

Tiara is the only fiber variety flax recently been introduced in India. The water retted flax fibers were mechanically extracted and subjected to degum and bleach using various chemicals and enzymes and the treatment conditions were optimized. The tenacity and elongation of the fiber were found to be improved when ethylene diamine tetra acetate (EDTA) was used to degum the fiber before peroxide bleaching. The effect of hydrogen peroxide in flax bleaching was studied at different mediums. Oxalic acid and EDTA assisted peroxide bleaching shows 23% and 50% increase in tenacity and whiteness as compared to raw fiber. The characterization of fiber done through FTIR, SEM, and analysis of chemical composition, shows the removal of pectin and hemicellulose from the fiber as a result of chemical treatments.

The use of textile-grade fiber extracted from the Indian pineapple leaf is an unexplored area. Pineapple leaf fiber (PALF) is fine, soft, and moderately strong and is much acceptable for fashion garment. An attempt has been made to extract and soften Indian PALF from the pineapple leaves by decortication and subsequent water retting. Decorticated cum retted fiber has shown better physicomechanical and surface appearance properties than decorticated fiber. Fine yarn (38 tex) was spun in a suitable spinning system, and the property performance was found to be suitable to make eco-sustainable novelty fabric. Fabric was developed by using cotton as warp yarn and PALF-based yarn as weft in a handloom. The developed fabric shows very good physical and mechanical properties, desired for apparels. This inferred that Indian PALF may be successfully used to make eco-niche apparel quality fabric as well as novelty textiles.

Recipes for bleaching of coconut fiber at both ambient and elevated temperature were investigated using appropriate statistical design of experiments using hydrogen peroxide with essential bleaching assisting auxiliaries. The statistical tool is also being utilized to suggest optimized recipe for the treatments considering mainly whiteness index, yellowness index, and tenacity. Statistical computation affirmed need of higher amount of bleaching chemicals in elevated temperature than ambient bleaching. Both the bleaching treatments were resulting in small mass loss essentially of noncellulosic nature including lignin and thus result in improved mechanical properties. The change in whiteness and yellowness index of the bleached fiber under the shed storage condition for duration of 2 years was found to be negligible.

Turn-on fluorescent probes show enhanced emission upon DNA binding, advocating their importance in imaging cellular DNA. We have probed the DNA binding mode of thiazole-coumarin (TC) conjugate, a recently reported hemicyanine-based turn-on red fluorescent probe, using a number of biophysical techniques and a series of short oligonucleotides. TC exhibited increased fluorescence anisotropy and decreased absorbance (~50%) at low [DNA]/[TC] ratio. Although the observed hypochromicity and the saturating value of [DNA base pair]:[TC] ratio is consistent with a previous study that suggested intercalation to be the DNA binding mode of TC, a distinctly different and previously unreported binding mode was observed at higher ratios of [DNA]:[TC]. With further addition of DNA, only oligonucleotides containing AnTn or (AT)n stretches showed further change-decreased hypochromicity, red shifted absorption peaks and concomitant fluorescence enhancement, saturating at about 1:1 [DNA]: [TC]. 1H-NMR chemical shift perturbation patterns and H1'-H6/H8 NOE cross-peaks of the 1:1 complex indicated minor groove binding by TC. ITC showed the 1:1 DNA binding event to be endothermic (ΔH° ~ 2 kcal/mol) and entropy driven (ΔS° ~ 32 cal/mol/K). Taken together, the experimental data suggest a dual DNA binding mode by TC. At low [DNA]/[TC] ratio, the dominant mode is intercalation. This switches to minor groove binding at higher [DNA]/[TC], only for sequences containing AnTn or (AT)n stretches. Turn-on fluorescence results only in the previously unreported minor groove bound state. Our results allow a better understanding of DNA-ligand interaction for the newly reported turn-on probe TC.

Turn-on fluorescent probes show enhanced emission upon DNA binding, advocating their importance in imaging cellular DNA. We have probed the DNA binding mode of thiazole-coumarin (TC) conjugate, a recently reported hemicyanine-based turn-on red fluorescent probe, using a number of biophysical techniques and a series of short oligonucleotides. TC exhibited increased fluorescence anisotropy and decreased absorbance (~50%) at low [DNA]/[TC] ratio. Although the observed hypochromicity and the saturating value of [DNA base pair]:[TC] ratio is consistent with a previous study that suggested intercalation to be the DNA binding mode of TC, a distinctly different and previously unreported binding mode was observed at higher ratios of [DNA]:[TC]. With further addition of DNA, only oligonucleotides containing AnTn or (AT)n stretches showed further change—decreased hypochromicity, red shifted absorption peaks and concomitant fluorescence enhancement, saturating at about 1:1 [DNA]: [TC]. 1H-NMR chemical shift perturbation patterns and H1’-H6/H8 NOE cross-peaks of the 1:1 complex indicated minor groove binding by TC. ITC showed the 1:1 DNA binding event to be endothermic (ΔH° ~ 2 kcal/mol) and entropy driven (ΔS° ~ 32 cal/mol/K). Taken together, the experimental data suggest a dual DNA binding mode by TC. At low [DNA]/[TC] ratio, the dominant mode is intercalation. This switches to minor groove binding at higher [DNA]/[TC], only for sequences containing AnTn or (AT)n stretches. Turn-on fluorescence results only in the previously unreported minor groove bound state. Our results allow a better understanding of DNA-ligand interaction for the newly reported turn-on probe TC.

Tubulin is a hetero-dimeric protein that polymerizes into microtubules and facilitates, among other things, eukaryotic cell division. Thus, any agent that interferes with tubulin polymerization is of therapeutic interest, vis-à-vis cancer. For example, colchicine is known to prevent tubulin polymerization by binding at the heterodimeric interface of αβ-tubulin. Crystal structures of tubulin bound to colchicine have shown that the dynamical conformation of a loop (βT7) plays an important role in colchicine binding. The βT7 loop dynamics also plays an important role in yielding curved versus straight αβ-tubulin dimers, only the latter being compatible with the microtubule assembly. Understanding the molecular mechanism of inhibition of microtubule assembly can lead to development of better therapeutic agents. In this work we were able to capture the βT7 loop flip by performing 200 ns molecular dynamics simulation of ligand-free αβ-tubulins. The loop flip could be described by only two independent collective vectors, obtained from principal component analysis. The first vector describes the flip while the second vector describes the trigger. The collective variables identified in this work is a natural reaction coordinate for functionally important tubulin dynamics, which allowed us to describe in detail the interaction network associated with the flip and the overall straight/curved conformational equilibrium.

The degummed mulberry silk waste and eri silk waste were blended with degummed and bleached pineapple leaf fibers (PALF) at fiber stage in different proportions, and spun into yarn in a jute spinning system. The 90-tex blended yarn thus developed was analyzed for different physico-mechanical properties. Properties of fabric developed in a traditional handloom using 2/40-s cotton as warp and blended yarn as weft were also analyzed. The quality parameters, viz., tensile property, crease recovery, fabric cover, stiffness, drape, and thickness of the developed fabric, met essential apparel requirements. A comparative subjective evaluation of the fabric quality, viz., aesthetic appearance, luster, and texture, was made with the help of a group of people from different age, educational, and occupational background to examine its marketability; all respondents felt that appearance of PALF with silk waste was excellent. Texture and luster were found to be from medium to moderate. About 95% of respondents felt that fabric was crispy.

Study aimed at recovery of lignin from the reused residual liquor of chemical retting bath of coconut fiber caused by partial delignification to make it soft. The lignin of 8.9% was obtained after recovery (maintaining pH 2.0 for 1 h at ambient temperature) and further purification. Extracted lignin is characterized through FTIR, TGA and particle size analysis. FTIR showed absence of polysaccharides in purified lignin. TGA indicates presence of higher methyl-aryl ether groups than aromatic groups in lignin of coconut fibre. Analysis reveals about 91% of particles in the rage of 1–500 µm, which shows its good dispersiblity in fluid. Recovery of lignin associated with two benefits i.e., diversified use of extracted pure lignin and reduction of organic load of the waste liquor to make it suitable for discharge.

Integrase Interactor 1 (INI1/hSNF5) is a component of the hSWI/SNF chromatin remodeling complex. The INI1 gene is either deleted or mutated in rhabdoid cancers like ATRT (Atypical terratoid and rhabdoid tumor). INI1 is also a host factor for HIV-1 replication. INI1 binds DNA non-specifically. However, the mechanism of DNA binding and its biological role are unknown. From agarose gel retardation assay (AGRA), Ni-NTA pull-down and atomic force microscopy (AFM) studies we show that amino acids 105-183 of INI1 comprise the minimal DNA binding domain (DBD). The INI1 DBD is absent in plants and in yeast SNF5. It is present in Caenorhabditis elegans SNF5, Drosophila melanogaster homologue SNR1 and is a highly conserved domain in vertebrates. The DNA binding property of this domain in SNR1, that is only 58% identical to INI1/hSNF5, is conserved. Analytical ultracentrifugation studies of INI1 DBD and INI1 DBD:DNA complexes at different concentrations show that the DBD exists as a monomer at low protein concentration and two molecules of monomer binds one molecule of DNA. At high protein concentration, it exists as a dimer and binds two DNA molecules. Furthermore, isothermal calorimetry (ITC) experiments demonstrate that the DBD monomer binds DNA with a stoichiometry (N) of ∼0.5 and Kd = 0.94 µM whereas the DBD dimer binds two DNA molecules sequentially with K'd1 = 222 µM and K'd2 = 1.16 µM. Monomeric DBD binding to DNA is enthalpy driven (ΔH = -29.9 KJ/mole). Dimeric DBD binding to DNA is sequential with the first binding event driven by positive entropy (ΔH'1 = 115.7 KJ/mole, TΔS'1 = 136.8 KJ/mole) and the second binding event driven by negative enthalpy (ΔH'2 = -106.3 KJ/mole, TΔS'2 = -75.7 KJ/mole). Our model for INI1 DBD binding to DNA provides new insights into the mechanism of DNA binding by INI1.