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The effect of H2/CO addition on flame dynamics of propane-air mixtures in a stepped microcombustor with heat recirculation was investigated experimentally. Unstable flame propagation regimes and their transition modes were observed for a range of mixture velocities (5���8 m/s) and equivalence ratios (0.6���0.95). Up to 60% H2 addition to lean propane-air mixtures helps improve the flame stability range in the combustor. The suppression of these flame instabilities with H2 addition is attributed to the increase in the overall mixture reactivity and burning velocity. The enhancement in OH intensity with H2 addition indicated a change in the elementary reactions, thereby affecting the flame dynamics. Contrary to H2 addition, CO addition does not show any noticeable effect on the formation of stable flame modes. The change in mixture properties and burning velocity leads to a change in the flame behavior and alters the heat release rate due to H2 addition to propane-air mixtures. A higher percentage of H2 addition led to the reappearance of the unstable (rotating) flames in the microcombustor. Intrinsic flame instabilities appeared at higher H2 percentages due to differential diffusion and increased thermal-wall coupling effects.

Sprouted millets are excellent sources of energy-yielding compounds, and their nutrients are highly bioavailable. Also, herbs and spices are best known for their health-benefitting properties and give flavors aroma and taste, respectively. By combining all the three basic raw materials of the product along with natural gluten substitutes like Xanthan gum or wheat flour itself would serve as a better valuable option to substitute unhealthy maida noodles. The preliminary experiments were conducted with the ratios of millet flour and wheat flour as 1:1, 1:2, 1:3, 2:3, 3:2, 2:1, 3:1 which were found from one-factor-at-a-time (OFAT). Also, 30 different trails obtained from response surface methodology (RSM) were performed. From the results of the above experiments conducted, further tests were carried out by mixing two parts of the millet flour along with three parts of the wheat flour as this ratio was found to have better sensory attributes and more nutritional values (majorly protein, fiber, fat, iron, potassium, magnesium and vitamins). The sensory evaluation was conducted among individuals and groups by using 9-point Hedonic scale. Proximate analysis was carried out for the optimized nutrient-rich herbal noodles.

Methane is the primary component of natural gas, coal bed gases, shale gas and natural gas hydrates, and its commercially recoverable amounts exceed those of petroleum and coal by a few orders of magnitude. The strong C-H bonds of methane make its selective and controlled activation/dissociation difficult and this impedes the widespread utilization of this small alkane as a chemical feedstock to make value added chemicals, fuels and materials. Thus, developing alternate techniques, synthesising new catalytic materials and gaining fundamental mechanistic insights into C-H bond activation on known catalytic surfaces are pivotal to making ‘methane to chemicals and fuels’ a reality. Using state of the art quantum chemical simulations, it is shown for the first time that mechanical impact of methane molecules induces the dissociation of their strong C-H bonds. This novel bimolecular ‘coupling induced dissociation mechanism’ is demonstrated to convert methane molecules undergoing mechanical impact, directly to C2 hydrocarbons like ethane and ethylene. The impact induced vibrational excitation of the molecules allow successive transitions to lower potential energy states, leading to the concerted dissociation of C-H bonds of the molecules and coupling of the carbon atoms. Using ab initio molecular dynamics and Metadynamics simulations, it is shown that the mechanical impact of methane on an inactive transition metal like copper, in the form of nanoclusters, can dissociate it with activation free energy barriers between 60 and 90 kJ mol-1. The impact induced vibrational excitation of the molecule and the formation of a collision complex, which serves as a precursor for the dissociation of methane are key reasons for the low free energy barriers. Additionally, the small 3-dimensional copper nanoclusters have electronic structure and morphological features which favour the impact induced dissociation of methane while subsequent dehydrogenation steps have high barriers. The stabilization of the transition state and the products of dissociation (CH3 and H) by the under-coordinated Cu-O pair on the CuO surfaces, enable the dissociation of methane with an activation energy barrier as low as 76 kJ mol-1 on the most stable CuO(111) surface, compared to the barrier of 170 kJ mol-1 on Cu(111) surface. Thus, oxygen enhances the activity of copper in methane dissociation. The stronger the H chemisorption on the surface lattice oxygen on the different CuO surfaces, the more active is the surface in dissociating methane, making H chemisorption energy a descriptor for the reactivity of the surface. The weaker the copper- lattice oxygen interaction on the surface, the stronger is the H chemisorption on the lattice oxygen. The difference in the intrinsic metal- oxygen interaction on the different CuO surfaces is the root cause for the differences in their reactivity. In contrast to CuO, the 5-coordinated surface lattice oxygen on the most stable NiO surface, NiO(100), makes the surface inactive for methane dissociation with activation barrier of 136 kJ mol-1 compared to 70 kJ mol-1 on Ni(100) surface. NiO surfaces are as active as metallic Ni for methane dissociation when 1) the surface lattice oxygen is 4 coordinated as in the less stable NiO(110) surface; 2) NiO has surface Ni vacancies; and 3) NiO is doped with low valent dopants like Li. On comparing un-doped and doped surfaces, the H chemisorption energy, the descriptor for the reactivity of the lattice oxygen on different NiO surfaces, was found to have a weaker correlation with the intrinsic binding strength of the lattice oxygen on the surfaces. Low valent dopants like Li increase the activity of surface lattice oxygen for methane dissociation by lowering the binding strength of the surface lattice oxygen. In summary, this thesis reveals unusually high reactivity of methane resulting from collisional impact. The findings have implications for understanding of certain planetary phenomena, offer an explanation for the genesis of ‘abiogenic petroleum’ on the earth and also indicate opportunities for the commercial exploitation of methane. Insights into the role of lattice oxygen, vacancies and dopants on metal oxides in methane dissociation, and H chemisorption energy as a descriptor for reactivity can serve as guidelines in screening and designing efficient multifunctional catalysts for methane dissociation and oxidation reactions. DOCTOR OF PHILOSOPHY (SCBE)

The compliant nature of exosuits makes them ideal for providing assistance to complex joints like the shoulder. Exosuits require soft, compact and accurate sensing units for reliable feedback control. In this work, we introduce an OpenSim simulation-based prototype of a proprioception-inspired sensing framework for a multi-DoF shoulder exosuit. The prototype is used to study the feasibility of the sensing system concept to accurately track multiple degrees of freedom (DoFs) of the shoulder simultaneously. The sensing system fuses data from 4 custom string poten-tiometers (SPs), that work together to sense the joint angles at the shoulder. The tendon-routing of the SP modules in the exosuit is proprioception-inspired and based on the organization of the muscles influencing shoulder movement. The sensor fusion/mapping of the simulation data from multi-sensor space to joint space is a multivariate multiple regression problem and was solved using Multi-Layer Perceptron (MLP) & Long Short-Term Memory (LSTM) neural networks. A simulation of the framework in OpenSim on 200,000 random shoulder movements achieved a root mean square error (RMSE) of $\approx 0.2^{\mathrm{o}}$ when trained on 70,000 random movements and tested on 130,000 random movements in both DoFs simultaneously.

Motor rehabilitation and assistance post-stroke are becoming a major concern for healthcare services with an increasingly aging population. Wearable robots can be a technological solution to support gait rehabilitation and to provide assistance to enable users to carry out activities of daily living independently. To address the need for long-term assistance for stroke survivors suffering from drop foot, this paper proposes a low-cost, assistive ankle joint exoskeleton for gait assistance. The proposed exoskeleton is designed to provide ankle foot support thus enabling normal walking gait. Baseline gait reading was recorded from two force sensors attached to a custom-built shoe insole of the exoskeleton. From our experiments, the average maximum force during heel-strike (63.95 N) and toe-off (54.84 N) were found, in addition to the average period of a gait cycle (1.45 s). The timing and force data were used to control the actuation of tendons of the exoskeleton to prevent the foot from preemptively hitting the ground during swing phase.

For assistive devices to seamlessly and promptly assist users with activities of daily living (ADL), it is important to understand the user’s intention. Current assistive systems are mostly driven by unimodal sensory input which hinders their accuracy and responses. In this paper, we propose a context-aware sensor fusion framework to detect intention for assistive robotic devices which fuses information from a wearable video camera and wearable inertial measurement unit (IMU) sensors. A Naive Bayes classifier is used to predict the intent to move from IMU data and the object classification results from the video data. The proposed approach can achieve an accuracy of 85.2% in detecting movement intention.

The design of comfortable and effective physical human robot interaction (pHRI) interfaces for force transfer is a prominent challenge for coupled human-robot systems. Forces applied by the robot at the fingers create reaction forces on the dorsal surface of the hand, often leading to high pressure concentrations which can cause pain and discomfort. In this paper, the interaction between the pHRI interface and the dorsal surface of the hand is systematically characterized, and a new method for the design of comfortable interfaces is presented. The variability of the stiffness of the hand dorsum is quantified experimentally, and this data is used to minimize the peak pressure exerted on the hand dorsum, by varying the stiffness profile of the pHRI interface. This optimized design is demonstrated to improve the pressure distribution over the hand dorsum where the robot is attached to the hand. Additionally, to enable informed design choices, the effects of varying the stiffness of the pHRI interface on relative displacement between the robot and the hand dorsum are also characterized. This optimization approach to designing pHRI interface can be extended to different limbs, especially when there is a transfer of high moment loads to the human body, provided the appropriate stiffness data is available.

The utilization of low frequency ultrasound (US) offers a straightforward and powerful tool for the production of nanostructured materials, in particular for structurally stable, highly crystalline, and shape-controlled catalytic materials. Herein, we report an unconventional strategy for the synthesis of CuO nanoleaves within 5 min of US irradiation. The as-obtained CuO nanoleaves were found to be selective in the base-free aqueous oxidation of glycerol to dicarboxylic acids (78% yield of tartronic and oxalic acids), in the presence of hydrogen peroxide (H2O2) and under mild reaction conditions. Density Functional Theory (DFT) investigations revealed a synergy between the CuO catalyst and H2O2 in maintaining the structural integrity of the catalyst during the reaction, creating alternative efficient pathways for the selective formation of dicarboxylic acids. Isotope labeling experiments using H218O2 further confirmed that oxygen from hydrogen peroxide, not from CuO, was preferentially incorporated into the dicarboxylic acid, significantly preserving the monoclinic structure of the CuO catalyst.

A significant fraction of the world population is plagued by neuromuscular disorders which have no cure other than symptomatic management. An increasingly aging world population would inevitably lead to a further rise in these numbers. The management of the manifestations of many neuromuscular diseases ranging from Parkinson’s disease to stroke has been an active research topic in robotics since the 1960s. Pivotal advances in sensing, actuation, energy sources, and computing technologies have facilitated an increased penetration of wearable robotics into patient rehabilitation and assistance. Furthermore, breakthroughs in research areas including material sciences and new actuation schemes are further accelerating the development of wearable robotics. The purpose of this chapter is to provide a review of robotic devices for upper-limb rehabilitation and assistance. A discussion of the state-of-the-art in design, actuation, and intention-sensing technologies is presented. The chapter also outlines challenges hindering the clinical translation of these technologies and highlights future research opportunities.

Hydride transfer changes the charge structure of the reactant and thus, may induce reorientation/reorganization of solvent molecules. This solvent reorganization may in turn alter the energetics of the reaction. In the present work, we investigate the intramolecular hydride transfer by taking Lewis acid catalyzed glucose to fructose isomerization as an example. The C2-C1 hydride transfer is the rate limiting step in this reaction. Water and methanol are used as solvents and hydride transfer is simulated in the presence of explicit solvent molecules, treated quantum mechanically and at a finite temperature, using Car-Parrinello molecular dynamics (CPMD) and metadynamics. Activation free energy barrier for hydride transfer in methanol is found to be 50 kJ mol(-1) higher than that in water. In contrast, in density functional theory calculations, using an implicit solvent environment, the barriers are almost identical. Analysis of solvent dynamics and electronic polarization along the molecular dynamics trajectory and the results of CPMD-metadynamics simulation of the hydride transfer process in the absence of any solvent suggest that higher barrier in methanol is a result of non-equilibrium solvation. Methanol undergoes electronic polarization during the hydride transfer step. However, its molecular orientational relaxation is a much slower process that takes place after the hydride transfer, over an extended timescale. This results in non-equilibrium solvation. Water, on the other hand, does not undergo significant electronic polarization and thus, has to undergo minimal molecular reorientation to provide near equilibrium solvation to the transition state and an improved equilibrium solvation to the post hydride shift product state. Hence, the hydride transfer step is also observed to be exergonic in water and endergonic in methanol. The aforementioned explanation is juxtaposed to enzyme catalyzed charge transfer reactions, where the enhanced solvation of the transition and product states by enzymes, due to electrostatic interactions, reduces the activation free energy barrier and the free energy change of the reaction. Similarly, we suggest that, in the intramolecular hydride shift, improved solvation of the transition state and of the product state by water is achieved due to minimal polarization and reorientation, and (near) equilibrium solvation.

The design of effective and comfortable physical Human Robot Interaction (pHRI) interfaces for force transfer is a prominent challenge for coupled human-robot systems. Forces applied across the pHRI interface give rise to relative displacements across it. This is a result of the innate compliance of the system due to the presence of human soft tissue and device padding and can lead to errors in estimated position, as well as misalignment that could lead to discomfort or injury. Additionally, any loading applied by the robot creates reaction forces on the human body, often leading to high pressure concentrations at the interface which can cause pain and discomfort. In this thesis, we present a simulation environment that has been developed for the study of the pHRI interfaces and coupled human robot systems that involve them. The forces and displacements at the pHRI interfaces are systematically characterized via this simulation based approach, and a new method for design of these interfaces is presented. The simulation approach can be used along with appropriate human anthropometric data to design comfortable physical human robot interfaces for different parts of the human body as well. This can be especially useful when there is a transfer of high moment loads across small interface surfaces or very soft regions of the body. In this thesis, however we focus on the application of the simulation based approach to case studies of pHRI interfaces of hand orthoses, with specific use of the Maestro hand exoskeleton. Experimental characterization with the Maestro system and analytical studies of the same interfaces are also presented for comparison and verification of the numerical results given by our simulation approach.

Advances in optical imaging, and probe-based Confocal Laser Endomicroscopy (pCLE) in particular, offer real-time cellular level information for in-vivo tissue characterization. However for large area coverage, the limited field-of-view necessitates the use of a technique known as mosaicking to generate usable information from the incoming image stream. Mosaicking also needs a continuous stream of good quality images, but this is challenging as the probe needs to be maintained within an optimal working range and the contact force controlled to minimize tissue deformation. Robotic manipulation presents a potential solution to these challenges, but the lack of haptic feedback in current surgical robot systems hinders the technology's clinical adoption. This paper proposes a sensorless alternative based on processing the incoming image stream and deriving a quantitative measure representative of the image quality. This measure is then used by a controller, designed using model-free reinforcement learning techniques, to maintain optimal contact autonomously. The developed controller has shown near real-time performance in overcoming typical loss-of-contact and excess-deformation scenarios experienced during endomicroscopy scanning procedures.

BACKGROUND: Fast changing technology applications in intensive care units (ICUs) are believed to enhance the result of nursing care. We expect the nurses to work with constantly updated technology and presume that they are receptive to any revised version of medical devices. The nurse's perception on technology is infrequently discussed in hospitals or among medical device manufacturers. AIMS: The aim of this study was to assess the nurses' perception about the advancement of technology in ICUs. SETTINGS: The study was conducted among the nurses working in different ICUs in a selected tertiary care hospital in Bengaluru, India. MATERIALS AND METHODS: An exploratory study was done using a hybrid method of qualitative and quantitative techniques. Semi-structured interviews were conducted with nurses having ≥5 years of experience in ICUs, and thematic analysis was applied. Quantitative data were collected from the population of nurses with 1 year or more experience using survey questionnaire. STATISTIACAL ANALYSIS USED: ANOVA test and sample t-test were conducted on the applicable parameter. RESULTS: Most of the nurses found that high-tech equipment in ICUs is easy to operate, reduce their effort, prevent errors, and increase the comfort of the patient. The study found that nurses' perception about the advancement of technology does not vary according to age, experience, qualification, and whether they have attended any continued nursing education on technology applications. Statistically significant relationship was found between total perception and the nature of ICU in which the nurses work. CONCLUSIONS: The study found that nurses perceive advanced technology in ICU as beneficial. Nurses expressed their satisfaction about the advancement of technology, and they perceive it as a good learning opportunity for them. The participants expressed their need for more training when equipment with advanced technology or a revised version is brought in.

A numerical investigation of steady laminar premixed propane–air flames is presented. A three-dimensional simulation has been performed to examine the impact of operating conditions on steady-state characteristics of a perforated burner flame. A numerical simulation has been carried out using a reduced propane–air reaction mechanism having 30 species and 192 reactions. The results are validated against the one-dimensional flat-flame result obtained using PREMIX. Effects of the equivalence ratio, inlet velocity, hole–hole distance, and plate thermal conductivity on flame stability are examined. The flame stand-off distance increases with the increase in the inlet velocity. As the equivalence ratio increases, the heat flux to the plate increases as the flame moves closer to the plate. When the plate is adiabatic, the conical flame rests on the plate. The flame stand-off distance increases as the plate thermal conductivity is increased. The flame moves downstream of the plate as the distance between the adja...

Simple, accurate, precise, sensitive, and validated high-performance liquid chromatography (HPLC) and high-performance thin-layer chromatography (HPTLC)-densitometric methods were developed for simultaneous determination of fenofibrate (FEN), atorvastatin (ATO), and ezetimibe (EZE) in combined tablet dosage form. In Method A, the gradient RP-HPLC analysis was performed on a Shim-pack C18 column (150 × 6 mm id), using a mobile phase consisting of 0.1% formic acid and acetonitrile in solvent gradient elution for 25 min at a flow rate of 1.5 mL min−1. Quantification was carried out using a photodiode array UV detector at 245 nm. The employment of diode array detector allowed selectivity confirmation by peak purity evaluation. In Method B, the HPTLC analysis was carried out on an aluminum-backed sheet of silica gel 60F254 layer using toluene: methanol:triethylamine (8:1.5:0.1, v/v/v) as the mobile phase. Quantification was achieved with UV densitometry at 245 nm. The analytical methods were validated accordin...

The mechanism of glucose ring opening and isomerization to fructose, catalyzed by the Lewis acid catalyst CrCl3 in the presence of water, is investigated using Car-Parrinello molecular dynamics with metadynamics. Minimum energy pathways for the reactions are revealed and the corresponding free energy barriers are computed. Addition of glucose replaces two water molecules in the active [Cr(H2O)5OH](+2) complex, with two hydroxyl groups of glucose taking their place. Ring opening and isomerization reactions can only proceed if the first step involving the deprotonation of glucose is accompanied by the protonation of the OH(-) group in the partially hydrolyzed metal center ([Cr(C6H12O6)(H2O)3OH](+2) → [Cr(C6H11O6)(H2O)4](+2)). This provides further evidence that the partially hydrolyzed [Cr(H2O)5OH](+2) is the active species catalyzing ring opening and isomerization reactions and that unhydrolyzed Cr(+3) may not be able to catalyze the reactions. After the ring opening, the isomerization reaction proceeds via deprotonation, followed by hydride shift and the back donation of the proton from the metal complex to the sugar. Water molecules outside the first coordination sphere of the metal complex participate in the reaction for mediating the proton transfer. The hydride shift in the isomerization is the overall rate limiting step with a free energy barrier of 104 kJ mol(-1). The simulation computed barrier is in agreement with experiments.

A simple, rapid, and sensitive LC/electrospray ionization (ESI)-MS method was developed and validated for the simultaneous determination of rosuvastatin (ROS) and ezetimibe (EZE) in human plasma. Following liquid–liquid extraction, the analytes and an internal standard, atorvastatin (ATO), were separated using an isocratic mobile phase comprising 0.1% (v/v) formic acid–methanol (20 + 80, v/v) on an RP-C18 column. Detection was performed on a mass spectrometer by selected ion monitoring using their respective [M-H]– ions, m/z 480 for ROS, m/z 408 for EZE, and m/z 557 for ATO. For both analytes, the method was linear in the range of 0.1 to 10 ng/mL. Acceptable precision and accuracy were obtained for concentrations over the standard curve range. A run time of 4 min made it possible to determine many plasma samples/day. The validated LC/ESI-MS method can be used to study pharmacokinetics, bioavailability, and bioequivalence of combined dosage forms of ROS and EZE.

This paper reports the measurement of laminar burning velocities of DME (dimethyl ether)-air mixtures at higher mixture temperatures using planar flames stabilized in a controlled temperature mesoscale diverging channel. The reliability of this technique for flame speed measurement at high mixture temperatures has been established through various numerical studies using detailed 3-D computational model for DME-air mixtures. The distribution of fuel -air mass flux, reaction zone, and flame shape indicate that a planar flame is indeed formed in both transverse and depth directions of the channel. The stabilized flame is independent of any stretch effects except mild hydrodynamic strain due to channel divergence (30-50 s(-1)), and measured values of laminar burning velocities are within 5% of the actual value. The experiments were carried out at various equivalence ratios (phi = 0.7-1.4) and elevated mixture temperatures (350-640 K). The burning velocities and temperature exponents were determined using the planar flames stabilized at different mixture inlet velocities and temperatures. Slightly rich mixtures (phi = 1.1) point to the maximum burning velocity, in good agreement with recent literature at ambient conditions. Temperature exponents for different equivalence ratios increase to both sides of 4) = 1.1. Numerically calculated laminar burning velocities with different chemical kinetic schemes compared well with the measured burning velocities at higher mixture temperatures. (C) 2017 Elsevier Ltd. All rights reserved.

Financial regulation is a much debated topic for some time. The history of financial instruments started at a time when people started giving value to physical objects over and above its inherent utility. Right from the very beginning of their existence, it has been acknowledged that financial instruments are risky. There have been several legislative and regulatory attempts to regulate financial instruments. But every time the human ingenuity ensured that financial instruments remain afloat. Financial derivatives are a sub species of financial instruments No internationally accepted principles for regulation of financial instruments, especially financial derivatives exist. This article makes a comparative study of the approach taken by judiciary regarding the regulation of financial instruments in general and financial derivatives in particular. The US, UK and India are taken as sample countries, but major context is the Indian regulatory scenario.

Financial Derivatives have established themselves as a major driving force in the international monetary sphere in the recent past. Financial Derivatives were originally used as an effective monetary instrument to multiply the wealth through ripple effect, of late, these instruments are also used by banks and financial institutions to mitigate risk arising from the volatility of the underlying asset. This apart, derivatives along with the new generation monetary instruments such as investment securities in bearer form have already become the back bone of international economy. This paper attempts to study the policy frame work for regulation of financial derivatives.

This paper describes a validated high-performance thin-layer chromatography (HPTLC) method for the simultaneous determination of ivermectin (IVM) and albendazole (ALB) in combined tablet dosage forms. The HPTLC separation was carried out on aluminum-backed silica gel 60 F254 layers using toluene-ethyl acetateglacial acetic acid, 6:4:0.5 (ν/ν/ν), as the mobile phase. Quantification was achieved with UV detection at 247 nm. The developed analytical method was validated according to International Conference on Harmonization guidelines in terms of parameters such as accuracy, precision, linearity, and specificity. Good linearity was observed in the concentrations ranging from 0.12 to 0.54 and 8 to 36 μg per band for IVM and ALB, respectively. The recovery study results ranged from 98% to 101% for IVM and ALB, showing the accuracy of the method. The method was successfully applied for the analysis of the drugs in laboratory-prepared mixtures and commercial tablets. The developed method is simple, precise, and ...

Simple, accurate, precise, sensitive, and validated HPLC and HPTLC-densitometric methods were developed for simultaneous determination of amlodipine (AML), valsartan (VAL), and hydrochlorothiazide (HYD) in combined tablet dosage form. Method A, the gradient RP-HPLC analysis was performed on a Phenomenex Luna C18 (4.60 mm × 150 mm, 5 µ particle size) column, using a mobile phase consisting of 10 mM ammonium acetate buffer (pH 6.7) and methanol in solvent gradient elution for 20 min at a flow rate of 1 mL min−1. Quantification was carried out using a photodiode array UV detector at 238 nm. The employment of a diode array detector allowed selectivity confirmation by peak purity evaluation. Method B, the HPTLC analysis was carried out on an aluminum-backed sheet of silica gel 60F254 layers using chloroform: glacial acetic acid:n-butyl acetate (8:4:2, v/v/v) as the mobile phase. Quantification was achieved with UV densitometry at 320 nm. The analytical methods were validated according to International Conferen...

A new, simple, and rapid normal-phase high-performance thin-layer chromatography method was developed for the simultaneous separation of retinoic acid isomers (tretinoin and isotretinoin). The isomers were baseline-resolved on aluminum-backed silica gel 60 F254 layer using toluene-ethyl acetate-methanol (8:1:0.5, v/v) as the mobile phase. Quantification was achieved with ultraviolet (UV) detection at 334 nm. The developed analytical method was validated according to International Conference on Harmonization guidelines in terms of parameters like accuracy, precision, linearity, and specificity. Good linearity was observed in the concentrations ranging from 30 to 70 ng band−1 for both the isomers. Recovery study results ranged from 95 to 102% for both tretinoin and isotretinoin. The final optimized methodology was successfully applied to separate the isomers and was proven to be reproducible and accurate for its quantitative determination.

Diagnostic assays that leverage bloodborne neuron-derived (neuronal) nanoscale extracellular vesicles (nsEVs) as “windows into the brain” can predict incidence of Alzheimer’s Disease (AD) many years prior to onset. Beyond diagnostics, bloodborne neuronal nsEVs analysis may have substantial translational impact by revealing mechanisms of AD pathology; such knowledge could enlighten new drug targets and lead to new therapeutic approaches. The potential to establish three-dimensional nsEV analysis methods that characterize highly purified bloodborne nsEV populations in method of enrichment, cell type origin, and protein or RNA abundance dimensions could bring this promise to bear by yielding nsEV “omics” datasets that uncover new AD biomarkers and enable AD therapeutic development. In this review we provide a survey of both the current status of and new developments on the horizon in the field of neuronal nsEV analysis. This survey is supplemented by a discussion of the potential to translate such neuronal nsEV analyses to AD clinical diagnostic applications and drug development.