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Fuzzy entropy measures are valuable tools in decision-making when dealing with uncertain or imprecise information. There exist many entropy measures for Pythagorean Fuzzy Sets (PFS) in the literature that fail to deal with the problem of providing reasonable or consistent results to the decision-makers. To deal with the shortcomings of the existing measures, this paper proposes a robust fuzzy entropy measure for PFS to facilitate decision-making under uncertainty. The usefulness of the measure is illustrated through an illustration of decision-making in a supplier selection problem and compared with existing fuzzy entropy measures. The Technique for Order Performance by Similarity to Ideal Solution (TOPSIS) approach is also explored to solve the decision-making problem. The results demonstrate that the proposed measure can effectively capture the degree of uncertainty in the decision-making process, leading to more accurate decision outcomes by providing a reliable and robust ranking of alternatives.

One of the most essential ideas for tracing the best objects among a set of possible ones is decision-making theory. We make decisions to gain a wide range of advantages from them based on our previous experiences. The concept of Pythagorean fuzzy sets (PFS) was first established by Yager to provides a new technique to describe ambiguity with great precision when compared to intuitionistic fuzzy sets (IFS) and fuzzy sets (FS). The study of PFS is recently gaining importance due to its wide application in situations involving ambiguity. It can easily be merged with MADM techniques to solve real-life problems. However, many of these measures for PFS are ineffective in the sense that they have fundamental shortcomings that restrict them from providing reliable and consistent results. This paper provides a novel Pythagorean fuzzy entropy measure and its application to decision-making problem using technique for order preference by similarity of ideal solution (TOPSIS) on some real-life environment. Comparative study is also done for validation of the proposed measure.

Entropy is a significant mathematical instrument for determining ambiguous/fuzzy information. Entropy is indispensable for measuring ambiguity, first familiarized by Shannon (Syst Tech J 27:379–423, 1948) to extent the degree of uncertainty in likelihood distributions. Complex info processes are extensively pragmatic in decision-making processes. Created as per the notion of an exponential exponent for the fuzzy set, our exertion offers a measure of the power of an intuitive set of exponents. This article identifies a new measure of the exponential theorem on an intuitive set of equations. In addition, the necessary properties are displayed. By analyzing the results of the examples, it has been shown that this method is faster and more effective in practice.

ABSTRACTIn this study, superhydrophobic surfaces were fabricated using 1H,1H,2H,2H-perfluorooctyltriethoxysilane monolayer deposition on thermally oxidized brass. The superhydrophobic surface showed a contact angle (CA) of 155° with a CA hysteresis of 3.5°. The corrosion behaviour of developed superhydrophobic surface was evaluated using potentiodynamic polarization and electrochemical impedance spectroscopy (EIS) studies in 3.5% NaCl solution. The superhydrophobic surface showed exceptional corrosion behaviour with nearly 21 times higher corrosion resistance compared to as-received (AS) brass. The EIS analysis suggests the presence of Warburg impedance in the AS brass indicating diffusion phenomena, while superhydrophobic brass surface showed a reversed loop in the low-frequency spectra, signifying significantly delayed kinetics of the electrochemical system. The study provides a facile, promising means of developing highly corrosion-resistant surfaces in engineering materials.

The development of composite materials through hybridisation is receiving a lot of interest; due to the multiple benefits, this may bring to many industries. These benefits include decreased brittle behaviour, which is an inherent weakness for composite materials, and the enhancement of mechanical properties due to the hybrid effect, such as tensile and flexural strength. The effect of implementing hybrid composites as skins on composite sandwich panels is not well understood under high strain rate loading, including blast loading. This paper investigates the blast resilience of two types of hybrid composite sandwich panel against a full-scale explosive charge. Two hybrid composite sandwich panels were mounted at a 15 m stand-off distance from a 100 kg nitromethane charge. The samples were designed to reveal whether the fabric layup order of the skins influences blast response. Deflection of the sandwich panels was recorded using high-speed 3D digital image correlation (DIC) during the blast. It was concluded that the combination of glass-fibre reinforced polymer (GFRP) and carbon-fibre reinforced polymer (CFRP) layers in hybrid laminate skins of sandwich panels decreases the normalised deflection compared to both GFRP and CFRP panels by up to 41 and 23%, respectively. The position of the glass-fibre and carbon-fibre layers does not appear to affect the sandwich panel deflection and strain. A finite element model has successfully been developed to predict the elastic response of a hybrid panel under air blast loading. The difference between the maximum central displacement of the experimental data and numerical simulation was ca. 5% for the hybrid panel evaluated.

This research investigates whether the layup order of the carbon-fibre/glass-fibre skins in hybrid composite sandwich panels has an effect on impact response. Composite sandwich panels with carbon-fibre/glass-fibre hybrid skins were subjected to impact at velocities of 75 ± 3 and 90 ± 3 m s−1. Measurements of the sandwich panels were made using high-speed 3D digital image correlation (DIC), and post-impact damage was assessed by sectioning the sandwich panels. It was concluded that the introduction of glass-fibre layers into carbon-fibre laminate skins reduces brittle failure compared to a sandwich panel with carbon-fibre reinforced polymer skins alone. Furthermore, if the impact surface is known, it would be beneficial to select an asymmetrical panel such as Hybrid-(GCFGC) utilising glass-fibre layers in compression and carbon-fibre layers in tension. This hybrid sandwich panel achieves a specific deflection of 0.322 mm kg−1m2and specific strain of 0.077% kg−1m2under an impact velocity of 75 ± 3 m s−1. However, if the impact surface is not known, selection of a panel with a symmetric yet more dispersed hybridisation would be effective. By distributing the different fibre layers more evenly within the skin, less surface and core damage is achieved. The distributed hybrid investigated in this research, Hybrid-(GCGFGCG), achieved a specific deflection of 0.394 mm kg−1m2and specific strain of 0.085% kg−1m2under an impact velocity of 75 ± 3 m s−1. Blast loading was performed on a large scale version of Hybrid-(GCFGC) and it exhibited a maximum deflection of 75 mm following a similar deflection profile to those observed for the impact experiments.

Substrate–cell interactions for a bioimplant are driven by substrate’s surface characteristics. In addition, the performance of an implant and resistance to degradation are primarily governed by its surface properties. A bioimplant typically degrades by wear and corrosion in the physiological environment, resulting in metallosis. Surface engineering strategies for limiting degradation of implants and enhancing their performance may reduce or eliminate the need for implant removal surgeries and the associated cost. In the current study, we tailored the surface properties of stainless steel using submerged friction stir processing (FSP), a severe plastic deformation technique. FSP resulted in significant microstructural refinement from 22 μm grain size for the as-received alloy to 0.8 μm grain size for the processed sample with increase in hardness by nearly 1.5 times. The wear and corrosion behavior of the processed alloy was evaluated in simulated body fluid. The processed sample demonstrated remarkable improvement in both wear and corrosion resistance, which is explained by surface strengthening and formation of a highly stable passive layer. The methylthiazol tetrazolium assay demonstrated that the processed sample is better in supporting cell attachment, proliferation with minimal toxicity, and hemolysis. The athrombogenic characteristic of the as-received and processed samples was evaluated by fibrinogen adsorption and platelet adhesion via the enzyme-linked immunosorbent assay and lactate dehydrogenase assay, respectively. The processed sample showed less platelet and fibrinogen adhesion compared with the as-received alloy, signifying its high thromboresistance. The current study suggests friction stir processing to be a versatile toolbox for enhancing the performance and reliability of currently used bioimplant materials.

An in situcomposite coating on pure aluminium substrate was prepared by novel microwave processing of iron based metallic glass powder precursor. The microstructure obtained after processing comprised of a molybdenum rich harder phase uniformly distributed in iron rich softer phase. The hardness and modulus of each phase were obtained by nanoindentation. Scratch test across the substrate coating indicated good interface strength and strong adhesion of the coating with the substrate.

Abstract: Cavitation erosion (CE) of various components in hydroturbines is a critical issue. Several attempts have been made in the past to counter CE through various surface modification techniques. In this study, a novel attempt has been made to modify the surface properties of hydroturbine steel with the aid of friction stir processing (FSP). Metallurgical characterization of the processed steel was undertaken with the help of XRD, SEM/EDS, EBSD and optical microscopy. For mechanical characterization micro-hardness and cavitation erosion studies were conducted. EBSD results confirmed the presence of grains in nano range. Processed steel showed gain in hardness of the order of 160 % in comparison to unprocessed steel. XRD results show a significant variation in the type and quantity of various phases in pre- and post processed steel. It was observed that FSPed steel showed a significant improvement in the erosion resistance in contrast to the unprocessed steel.

Abstract: In this study, AZ91 based hybrid nanocomposite was fabricated using mixture of TiC and alumina by friction stir processing (FSP). FSP of AZ91 was conducted with as well as without particle addition and under different cooling conditions. Distribution of nano TiC and Al2O3 particles in the Mg matrix was studied using SEM. Grain size analysis of the as-cast and FSP AZ91/(TiC + Al2O3) composite was done using optical microscopy. The performance of the fabricated nanocomposite was investigated using microhardness, bulk hardness and scratch tests. Microhardness testing was done at 50 gf load and bulk hardness at 5 Kgf load. Scratch test was performed at 2 and 5 N normal load values on a universal tribometer using Rockwell indentor. AZ91/(TiC + Al2O3) composite exhibited improved mechanical properties.

Abstract: BackgroundDespite technical advances in coronary artery bypass grafting (CABG), early postoperative myocardial ischaemia still remains a challenging problem. The aim of this study was to determine the incidence, clinical features, angiographic characteristics, and management of early graft failure in the present CABG era. MethodsBetween January 1997 and December 2002, 1731 patients underwent CABG at our institution. Coronary angiography was performed in patients with clinical evidence of early postoperative ischaemia (≤3 months). Thirty of these patients with graft failure constituted the population of this study. ResultsOff-pump and on-pump CABG were almost evenly performed in these patients [n=16 (53%) and n=14 (47%) respectively]. Acute myocardial infarction and unstable angina were the leading indications for coronary angiography in the majority of patients [n=28 (93%)]. The most common cause of graft failure was occlusion / thrombosis [n=20 (67%)]. Percutaneous coronary intervention (PCI) was offered to the majority of patients [n=22 (73%)]. Of these patients, 14 underwent PCI to native coronary arteries, whereas eight underwent PCI to the culprit vessel. Three patients underwent reoperation, and five received medical management. Four patients (13%) died in hospital (two after redo CABG, one after unsuccessful PCI, and one patient managed medically). Two patients (7%) had nonfatal major complications (one non-ST-elevation myocardial infarction and one stroke). ConclusionEarly graft failure generally presents as acute coronary syndrome. Graft occlusion/ thrombosis is the leading cause of ischaemia. Patients with graft failure can undergo PCI with a relatively low risk, but the need for redo CABG in associated with a high mortality. (Neth Heart J 2009;17:13-7.)

The distribution of Zn, Cu, Mn, and Fe in the pedosphere varies with the genetic horizons that are evolved through soil-forming processes altering parent material. In Alfisols, the driving processes are eluviation and illuviation. Our objective was to determine the relationship of soil-forming processes with the distribution of total and DTPA-extractable forms of Zn, Cu, Mn, and Fe in Alfisols. Nine profiles, three each from concave hill slope in the Siwalik Himalaya, piedmont, and plain on a topo-sequence in Punjab, were sampled. Soil samples were collected from each horizon and analyzed for total and DTPA-extractable Zn, Cu, Mn, and Fe. Total content ranged from 36 to 113 mg kg−1for Zn, from 12 to 42 mg kg−1for Cu, from 210 to 586 mg kg−1for Mn, and from 1.42 to 4.82% for Fe. DTPA-extractable content ranged from 0.22 to 2.30 mg kg−1for Zn, from 0.30 to 2.58 mg kg−1for Cu, from 2.80 to 86.5 mg kg−1for Mn, and from 3.10 to 30.5 mg kg−1for Fe. Total contents of Zn, Mn, and Fe were highest in the profiles of the piedmont, moderate in the profiles of the concave hill slope, and lowest in the profiles of the plain depicting their association with landform units. DTPA-extractable forms decreased with depth, increased with increase in organic matter, and decreased with increase in clay content. There were no correlations between total contents of Zn and Mn with soil separates, although total contents of Fe and Cu increased with increase in clay content. Invariably, illuvial horizons contained higher amounts of total elements than eluvial and subsoil horizons. Data showed that the landform units rule the profile contents and the pedogenic processes govern the distribution of the total elements, whereas organic carbon controls DTPA-extractable forms.

The effect of trovafloxacin, ciprofloxacin and ceftriaxone on cytokine production of human peripheral blood mononuclear cells (PBMCs) was examined. PBMC responses were measured after stimulation with lipopolysaccharide (LPS), lipoteichoic acid (LTA) or killed or viable Streptococcus pneumoniae and Haemophilus influenzae. Trovafloxacin inhibited the production of tumour necrosis factor alpha (TNF-alpha), interleukin-1beta (IL-1beta), IL-6 and IL-8 by PBMCs after stimulation with either LPS or LTA by 83%. Similar inhibition occurred in PBMCs incubated with killed or live bacteria and trovafloxacin, but not with ciprofloxacin or ceftriaxone. The relevance of this in vitro observation was explored by examining TNF-alpha and IL-6 responses in trovafloxacin-treated mice. Serum concentrations of both cytokines 1 h after LPS challenge were 95% less than serum concentrations in mice that were not given trovafloxacin. Reverse transcription- polymerase chain reaction studies of the mechanisms determining cytokine down-regulation demonstrated that trovafloxacin reduced TNF-alpha, IL-1beta and IL-6 mRNA to levels similar to those of unstimulated cells. These observations indicate that trovafloxacin can consistently and significantly reduce production of cytokines that play an important role in sepsis. In vitro, this effect can occur in the presence of bacteriolysis and is associated with inhibition of transcription of cytokine genes.

Slurry erosion–corrosion is a severe issue for many engineering components used in marine, petrochemical, and agricultural sectors. The deleterious effects of the slurry erosion–corrosion significantly lower the service life and enhance the maintenance cost. For limiting the slurry erosion–corrosion effects, there is a need for high-performance advanced materials. In the present work, equimolar MoNbTaTiZr high-entropy alloy (HEA) was developed, and its slurry erosion–corrosion behavior was investigated. For comparison, conventionally used stainless steel SS316L was also investigated. The detailed microstructural characterization showed the presence of a two-phase bcc crystal structure in the HEA. The major bcc phase was predominantly composed of Ta, Mo, and Nb with the interdendritic region being rich in Ti and Zr. The MoNbTaTiZr HEA showed 2 times higher hardness than the SS316L steel. Under slurry erosion–corrosion condition, the HEA showed 3.5 times higher resistance while under erosive conditions, two times better performance than the reference material. The analysis of the eroded surface morphology showed the presence of a mixed ductile–brittle erosion response for the HEA. The improved performance of the HEA is predominantly related to the high hardness and extremely high corrosion resistance. Electrochemical corrosion testing revealed that the HEA has 80 times lower current density than SS316L and high pitting resistance, resulting in low corrosion rates. The electrochemical impedance spectroscopy (EIS) findings showed a denser and highly stable passive layer. The results indicated that MoNbTaTiZr HEA could be effectively used for countering the slurry erosion–corrosion and corrosive conditions.

Distribution of sulfur and its three predominant forms in 10 lignitic coal seams developed in fluvial environments in east Texas was examined. The average sulfur content for individual seams varied from 0.88 to 3.98%, while the total sulfur content of 10‐cm sections of these seams varied from 0.53 to 16.79%. Sulfate sulfur was a minor component compared to pyritic or organic sulfur. The organic sulfur content determined by the standard American Society for Testing and Materials (ASTM) procedure as the difference between the inorganic sulfur (sulfate + pyritic sulfur) and the total sulfur in the original material, in general, remained uniform within a given lignite profile. A significant correlation was obtained between the organic sulfur content obtained by the ASTM procedure and a more direct method of density separation of specific gravity < 1.6 fraction and the determination of total sulfur in this fraction with an induction furnace and automatic titrator. Pyritic sulfur had the most variable distribution with a greater concentration of pyrite occurring at the seam fringes, which suggests the need for separate handling of these highpyrite content mine spoils for safe disposal.

Lignite overburden core samples obtained in the premining stage were size-fractionated and analyzed by x-ray diffraction and chemical methods to determine their mineralogical composition. Although we found a broad similarity in crystalline mineral assemblage in these fluvial sediments from east Texas, we also observed wide variations in the distribution of smectite, kaolinite, mica, vermiculite, and chlorite, with sample location and depth. Electron microscopic investigations indicated that localized concentrations of siderite were probably authigenic in origin. The physicochemical properties and mineralogical composition data obtained in these investigations suggest that segregation of existing low-fertility surface soils for top-dressing may be unnecessary, provided that pyrite-rich spoil material and clayey substrata are not deposited in the upper soil zone.

Scanning electron micrographs of pyrite separted from lignitic coal show the occurence of several morphological forms of simple and comopound particles. Porous and nonporous particles of pyrite crystals are sometimes scattered on the surfaces of grains. Framboids of individual pyrite crystals are porous and weekly aggregated into spheroids that are commonly 20 to 50 µ in diameter. Polyframboids are made up of framboids cemented together into irregular aggregates. Pyrite microcrystals are 0.25 to 1.5 µ across and, thus, have a large, exposed surface area. These findings suggest that sulfide oxidation and acidity formation will proceed at a relatively rapid rate when pyritic mine spoil is exposed to weathering forces.

The influence of mineralogical composition, saturating ions, and electrolyte concentration on the flocculation and dispersion behavior of various clay minerals was used to explain reductions in the hydraulic conductivity observed in many sodic soils containing little or no expandable clay minerals. Sodium-saturated clay minerals were found to differ in their sensitivity to flocculation by NaHCO3in the decreasing order: illite, vermiculite, smectite, and kaolinite. Critical salt concentrations (CSC) were 185, 58, 28 to 60, and 8 me/liter, respectively, for the above clays.

The whirling motion of a fixed-free viscoelastic shaft, whose model is based on the spring and dashpot (Kelvin element), is considered. We develop a precise determination of the system's stability by first obtaining its eigenvalues. It is shown that asymptotic stability exists as long as the angular speed of the shaft is below a certain critical value. On the other hand, the degree of stability first increases as the speed is increased but eventually decreases again.

Capium (elephant grass) chips were treated at 180°C for 1 to 3 h, solid concentrations 3 to 14%, with 50% aquous ethanol in a recently-developed reactor. About 70% delignification and 90% hemicellulose removal in solid form, and 95% glucose yield in 16h by enzymatic hydrolysis, were obtained under optimum reaction conditions. The effectiveness of lignocellulosic biomass fractionation is due largely to the reactor design which facilitates efficient separation of components and overcomes lignin condensation problems.

It has long been considered a general rule for nerve regeneration that the reinnervation of skeletal muscle is nonselective. Regenerating nerve fibers are supposed to reconnect with one skeletal muscle as readily as another according to studies covering a wide range of vertebrates (Weiss, 1937; Weiss & Taylor, 1944; Weiss & Hoag, 1946; Bernstein & Guth, 1961; Guth, 1961, 1962, 1963). Similarly, in embryogenesis proper functional connexions between nerve centers and particular muscles are supposedly attained, not by selective nerve outgrowth but rather through a process of ‘myotypic modulation’ (Weiss, 1955) that presupposes nonselective peripheral innervation. Doubt about the general validity of this rule and the concepts behind it has come from a series of studies on regeneration of the oculomotor nerve in teleosts, urodeles, and anurans and of spinal fin nerves in teleosts (Sperry, 1946, 1947, 1950, 1965; Sperry & Deupree, 1956; Arora & Sperry, 1957a, 1964).

In man and other mammals normal motor co-ordination is not restored, as a rule, after regeneration of a severed peripheral nerve-trunk (Sperry, 1945). The random misdirection of regenerating fibres into foreign muscles tends to prevent normal dissociated action within the re-innervated musculature. In contrast, larval amphibians have been found to show excellent recovery of motor function in the form of ‘homologous or myotypic response’ (Weiss, 1936, 1941) following the cutting and regeneration of limb-nerves, limb transplantation, and the crossconnecting of limb nerves to foreign muscles. Similarly, good restoration of muscle co-ordination has been observed in the pectoral fin of adult teleost fishes (Sperry, 1950, 1956). It has been suggested (Sperry, 1941, 1951) that such recovery is most easily explained in terms of a central readjustment of synaptic connexions to suit the altered pattern of peripheral innervation. Morphological or other direct evidence for such synaptic changes, however, has not been found.

Two rare benign tumours of the tongue, granular cell myoblastoma and neurofibroma, have been presented. A brief review of the literature with relevant pathological and therapeutic aspects of the lesions have been discussed.

Nystatin, a polyene antifungal antibiotic, induces systolic arrest of the isolated hearts of the frog, rat or rabbit. In the frog, heart failure induced by raising venous pressure was antagonised and the cardiac outflow was increased. Coronary flow in the perfused heart of the rat or rabbit was decreased.

The effects of hamycin, a cardiotonic polyene antibiotic, were studied on the perfused heart of the albino rat, a species resistant to the digitalis glycosides. Perfusion with a concentration of 1 × 1−8g./ml. induced systolic arrest in 15 to 20 min. This was preceded by auriculoventricular block and a decrease in the heart rate. Effects on the amplitude of contraction and coronary flow were however variable. Ouabain. 2 × 10−6g./ml. and propylene glycol, which was the solvent for hamycin, did not have any significant effects on this preparation.

Two-dimensional (2D) materials have gained enormous attention in recent years owing to their huge potential in future electronics and optics. On the one hand, conventional 2D materials like graphene, MoS2, h-BN are being intensively studied, on the other hand, search for novel 2D materials is at a rapid pace. In this study, we have investigated electrical properties of 2D nanosheets of ultrathin Indium Selenide (InSe), a member of the III-VI chalcogenides' family. The InSe layers were prepared via micromechanical cleavage of its bulk crystal and were integrated into a field-effect transistor (FET) device as the transport channel. On characterizing the InSe-based FETs, InSe showed n-type conductance with the mobility of 2.1x10[?]4 cm2V[?]1s[?]1.

Treatment of frog heart with hamycin, an antifungal antibiotic, effected an increase in the potassium content of perfusion fluid. Changes in sodium content were not observed.