A microfluidic bacteria culturing device with MALDI mass spectrometry detection

A novel microfluidic device was developed for bacterial cell culturing using mass spectrometry as the detector. One of the challenges in proteomics is to achieve high sensitivity in the identification of proteins in complex samples with widely varying concentrations. The main limitations for proteomic studies are relatively slow and labor-intensive steps such as cell culturing and protein digestion of small sample quantities. Microfluidics is a promising approach to increase throughput and to reduce the time-consuming steps that are necessary for proteomics. When an analytical detection method is combined with microfluidics it can overcome limitations that are important in the analysis of biological samples. In this work a microfluidic device was constructed from poly(methyl methacrylate) PMMA using hot embossing from a brass metal mold prepared from micro-milling and combined with off-line matrix assisted laser desorption-mass spectrometry mass spectrometry (MALDI-MS) for analysis. In this work, E. coli K12 strain was selected as a model for performing the analysis. Microfluidic devices were used to process the sample and mass spectrometry was used as detection method. The microfluidic device used in this study consists of three modules, capture, culture, and digestion chamber, integrated onto a single platform. The cells are captured on the microfluidic chip using polyclonal goat antibody on a modified PMMA surface, and are released using 0.25% trypsin, and transferred to the culture cell, which is filled with the growth medium. The temperature of the culture cell is maintained at 37 ºC using a heater and a PDMS cover slip was used for air perfusion. Samples collected at different culturing durations (4 h, and 10 h) are transferred to a micro-post bioreactor, which contains immobilized trypsin. The effluent from the microfluidic device was spotted onto a MALDI target and analyzed using MALDI time-of-flight mass spectrometry

A Quantitative Approach to Prioritize Sustainable Concrete

Cement industry consumes high energy and produces major emissions to the environment. In order to reduce the effects (environmental impact, energy, and resources) caused by conventional materials, various by-products and pozzolonic material are used to achieve sustainable concrete. Assessing the concrete performance based on multiple conflicting attributes is decisive and compelling. It is difficult to choose an alternative among the Supplementary Cementitious Materials (SCM) considering a set of quantitative performance attributes. Hence, the present study utilizes the theories of decision making to prioritize an alternative environmentally and technologically. The purpose of the present study is to observe the sustainable performance of five different concretes made of OPC, Fly ash, GGBS, Metakaolin and Composite Cement for a particular grade of concrete. The study has considered workability, strength attribute (compressive strength, split tensile and flexural strength) and durability attribute (Sorptivity and RCPT) at their respective optimum replacements. To prioritize an alternative material considering quantitative attributes, Technique for Order of Preference by Similarity to Ideal Solution (TOPSIS) is utilized. From the results, it is observed that considering all attributes, flyash based concrete has higher performance and is prioritized among others. The developed approach facilitates the decision-makers in the selection of a sustainable alternative

(R1511) Numerical Solution of Differential Difference Equations Having Boundary Layers at Both the Ends

In this paper, numerical solution of differential-difference equation having boundary layers at both ends is discussed. Using Taylor’s series, the given second order differential-difference equation is replaced by an asymptotically equivalent first order differential equation and solved by suitable choice of integrating factor and finite differences. The numerical results for several test examples are presented to demonstrate the applicability of the method

SEED EXTRACT OF ABELMOSCHUS MOSCHATUS MEDIK REVERSES NAF-INDUCED BEHAVIORAL CHANGES THROUGH NEURODEGENERATION AND OXIDATIVE STRESS IN BRAIN OF RAT

  Objective: This study reports protective effect of Abelmoschus moschatus seed extract against sodium fluoride-induced neurodegeneration through oxidative stress, neurohistological, and behavioral observations in Wistar rats.Methods: A total of 20 Wistar rats (around 250 g) were randomly classified into four groups, namely, control, fluoride (NaF), fluoride + A. moschatus seed aqueous extract (AMAE), and fluoride + A. moschatus seed ethanol extract (AMEE). The control group animals received normal tap water, fluoride group received fluoridated water at the rate of 40 mg/kg b. wt., 3rd group rats treated with fluoride (40 mg/kg b. wt.) + AMAE (300 mg/kg b. wt.), and 4th group rats treated with fluoride (40 mg/kg b. wt.) + AMEE (300 mg/kg b. wt.). Neurobehavioral responses of rotarod, hot plate, and maze learning tests and oxidantive stress markers including lipid peroxidation (LPO), GSH levels, superoxide dismutase, CAT, and GSH peroxidase (GPx) activities, and also histology with H and E as well as congo red staining were studied in control, fluoride, and A. moschatus seed extract treated against fluoride groups.Results: Decreased neurobehavioral responses with rotarod, hot plate, and maze and enhanced LPO (p<0.05) levels were found in fluoride received animals. Whereas, the superoxide dismutase (SOD), CAT, GSH, and GPx were decreased (p<0.05) in NaF treatment. The rats received seed extract along with NaF showed significant reversal of behavioral and oxidative stress markers and the effect of ethanol extract was more pronounced than aqueous extract. The fluoride-treated group showed disturbed cell structure and reduced number of cells in H and E as well as congo red staining which was reversed in cell morphology and restored cell number in seed extract against NaF-treated group. As a result of increased LPO, decreased antioxidant system, and decreased number of cells, neurodegeneration was observed resulting in the disturbance in functions associated with reported behavior.Conclusion: Okra with high antioxidants activity, seed extract showed reversal of LPO levels and antioxidant status in the brain tissue. And also plant extract administered rats displayed normal cell structure and number of cells than only fluoride received group. Therefore, the aqueous and ethanolic extract of A. moschatus plant seeds has neuroprotective effects against fluoride-induced motor, nociceptive, learning behavior, and on histological structure of brain through antioxidant mechanism. The ethanol extract has shown more efficacy than aqueous extract

DEM modelling and quantitative validation of flow characteristics and blending of pellets in a planar silo

Blending processes in a silo minimise the fluctuations in the property of bulk solids with the blending performance being strongly influenced by the flow pattern and operating mode among other process parameters such as batch size and type of input fluctuations. An accurate prediction of flow characteristics such as flow channel boundary and velocity profiles is important for understanding and quantifying the blending performance, thereby increasing the scope for new design by minimising the number of expensive pilot scale experiments required. In this thesis, the Discrete Element Method (DEM) is deployed to predict and understand the flow characteristics and blending of cylindrical plastic pellets in a planar flat bottom silo and a multi-flow blender (a silo with an insert and a blending tube). The predictions are validated against high-resolution velocity measurements analysed using Particle Image Velocimetry (PIV) technique. A planar model silo was built to measure the flow of pellets using PIV technique. The existing GeoPIV Matlab module was customised to extract the velocity fields in the Eulerian frame of reference and its accuracy has been verified. The developed tool was then applied to quantitatively investigate the mechanism of evolution of flow in a flat bottom silo and the dependency of the state of developed flow on the depth of the planar silo. It was shown that the development of flow during discharge can be divided into two stages: a rapid upward propagation of plug flow followed by a widening of the flow channel with increasing shearing boundaries. The size of the flow channel was found to be increasing with the depth of the silo. For the 100 mm deep silo, the flow is three dimensional with significant retardation in velocity at the frontal walls, whilst a negligible retardation was found for the 20 and 40 mm deep model silos. The thickness and frontal wall friction in planar silos thus play an important role in the development of flow patterns in model silos. In this thesis, DEM model calibration relating the macro-scale bulk friction and micro- scale particle friction at different rolling friction values was developed from DEM simulations of Jenike direct shear box. During the direct shear simulation, a constant normal force was achieved with the use of a shear lid geometry made with glued spheres thereby eliminating the use of a traditional servo control function. The influence of particle rotations and rolling friction on the limiting bulk friction for different particle sliding friction coefficients was explored. The accuracy of the calibration data was assessed by simulating the flow in a flat bottom silo and comparing the model predictions of flow rate, velocity profiles and flow channel boundary with the experiments. A good quantitative agreement was found between the experiment and simulations. The DEM model predictions were also compared with the kinematic model. Following the validation of the model, it was shown that the frontal friction and rolling friction are the influential parameters in simulating the flow patterns such as semi-mass and internal flow. It was further shown that flow transits from semi-mass flow to internal flow with the increase of frontal wall friction. The drastic influence of frontal wall friction on stress, flow patterns and force chains were analysed highlighting its implications on interpretations in 2D test silos. Finally, the developed DEM and PIV tools are employed to investigate blending in a flat bottom and multi-flow blender silo for different flow patterns. The analysis showed that the blending is more effective with the internal flow when compared to semi-mass flow in a flat bottom silo, in both continuous and discontinuous modes for a variety of process conditions such as batch size, the number of recirculation and frequency of input fluctuations. An algorithm was developed to evaluate the blending performance from the spatially averaged Eulerian velocity fields. The flow in a relatively large-scale multi-flow blender comprising nearly 606,000 particles, thereby fully replicating the test silo, was simulated and the challenges in reproducing the test conditions of continuous and discontinuous modes of operation were discussed. The flow patterns and blending were first analysed from the experiments in different configurations of the insert. Using the same input parameters for the model, it was shown that the model predictions of the velocity profiles along the height of the silo are in good agreement with the experiments. Internal flow, mixed flow and mass flow were predicted for the diverging, straight and converging insert configurations respectively and the blending performance for each of these configurations suggests an optimal configuration of the blender thereby demonstrating the potential of PIV and DEM in design optimisation. The possibility of conducting the DEM simulations under increased gravity in order to reduce the computational time has also been explored

Assessment of Right Ventricle by Echocardiogram

Assessment of right ventricular (RV) function is important to ascertain clinical outcome in patients with symptoms of right ventricular failure manifested as lower extremity swelling and abdominal congestion. RV function is not routinely assessed and reported in clinical practice. Unlike the bullet‐shaped left ventricle (LV), RV has a complex geometry with a triangular shape. RV is further divided into the inlet, trabecular apex, and infundibulum or conus. RV evaluation involves quantifying afterload and preload, assessing the mechanism and severity of tricuspid regurgitation (TR), and quantitative evaluation of RV performance. For quantification of RV size and function, we can use intravenous contrast for endocardial tracing of RV border to measure RV dimensions, tricuspid annular plane systolic excursion (TAPSE), fractional area change (FAC), Doppler index of myocardial performance (Tei index or myocardial performance index), pulsed wave or color Doppler tissue imaging systolic velocity [s\u27], or strain imaging. For qualitative evaluation of RV, the RV size is compared to the LV size in parasternal, short axis, and subcostal projections

Atypical teratoid/ rhabdoid tumour in adult - A rare case report

Atypical teratoid rhabdoid tumour is a rare and very aggressive malignant embryonal tumour of central nervous system (CNS) seen in infancy and early childhood. The exact incidence of childhood CNS AT/RT is difficult to determine because this tumor as a separate entity has been widely recognized only the last decade. Historically these tumors, also known as malignant rhabdoid tumour, were commonly mistaken as primitive neuroectodermal tumors because of certain similar morphological features on histopathological examination

Aggressive fibromatosis – Case report and brief review of literature

Aggressive fibromatosis is a benign tumor which arises from deep musculoaponeurotic structures and can occur anywhere in the body. It is characterized by local invasion and recurrence. It has been reported to occur in the head and neck (H & N) region, with 179 cases documented between 1968 and 2008