Fungi - an Amalgam of Toxins and Antibiotics: a Mini- Review

Fungi are eukaryotes with many functions. Earlier, fungi were classified in the plant kingdom but were later classified as a separate kingdom due to their unique cell walls. Fungi are heterotrophs like animals and are more closely related to animals. The perception of fungi is inconspicuous due to their small sizes and their ability to grow symbiotically in plants, animals, other fungi, and parasites. Fungi are used for their nutrition, fermentation potential, and bactericidal potential. However, fungi are also toxic due to certain bioactive compounds known as mycotoxins. Candida and Aspergillus are invasive species that contribute to a high percentage of mycoses in oncological and haematological patients. The mortality rate due to invasive aspergillosis and candidiasis is high, at 4% and 2%, respectively. In the agriculture sector, a significant contributor to damage to crops globally is the invasion of filamentous fungi. Fungi invasion destroys over 125 million tons of wheat, rice, soybeans, potatoes, and maize annually. If prevented, 600 million people may be fed. Therefore, it is vital to consider the dual role of fungi, therapeutic, and pathogenic

Causative Organisms, Clinical Course and Complications of Pyogenic Meningitis in Children

pyogenic meningitis, monitor clinical course and assess complications. Methods: The study was conducted in Paediatric department of Rawalpindi General Hospital, Rawalpindi, over a period of 1 year. Thirty patients were enrolled in the study. History, complete examination, routine investigations, blood culture and cerebrospinal fluid (CSF) routine examination and culture were performed. Cranial ultrasound and CT scan of brain were performed in selected patients. Treatment was given for ten days, and after discharge patients were followed upto 6 months. Data was entered and analyzed using computer programme SPSS version 10.0. Results: Mean age of patients was 40 + 39.2 months. Eighteen (60%) were male and 12 (40%) were females. The most common clinical presentation was fever (100 %) with mean duration 3.4 + 0.7 days. Cerebrospinal fluid culture was positive in 12 (40%) patients. The most common organism isolated was Streptococcus pneumoniae in 7 (23.3%).On follow up 6 (20%) patients had hearing loss. Thirteen (43.3%) patients fully recovered after therapy, 15 (50.0%) recovered with complications while 2 (6.6%) patients expired. Conclusion: The clinical features like loss of consciousness, signs of meningeal irritation (SOMI) and signs of raised intracranial pressure (ICP) are significantly associated with morbidity and mortality. The positive CSF culture, cranial ultrasound and CT scan findings are also associated with morbidity and mortality

Modeling of plasma dynamics during pulsed electron beam ablation of graphite.

Recent advances in the field of plasma nanofabrication suggest that plasma-based technologies may replace many of the conventional chemical and thermal routes in the synthesis of nanomaterials (with at least one dimension below 100 nm) and thin films. In contrast to the conventional processing routes, where only neutral species are involved, a plasma is made up of energetic species including ions, electrons, and excited molecules in addition to neutrals. Due to the highly energetic nature of interactions among these species and with other surfaces (substrates), a plasma allows for the formation of materials at higher rates even though their concentrations might be low as compared with those of neutral species in non-plasma based methods. While the mechanisms of the various interactions in a plasma are undoubtedly complex and require a fundamental understanding, they offer new opportunities for material nanofabrication. Pulsed electron beam ablation (PEBA) has recently emerged as a novel and promising technique for high quality thin films growth. Pulsed electron beam film deposition consists of many physical processes including target material heating, target ablation, plasma plume expansion, and film growth on a substrate. Electron beam ablation is a complex process, which comprises heating, phase change, and removal of a fine fraction from the target surface. Ablation strongly affects the space distribution, composition, mass transfer processes, which in turn has a critical bearing on the structure, stoichiometry and properties of thin films. Plasma plume expansion into an ambient gas is a fundamental issue in PEBA as the quality of thin films deposited onto the substrate depends on the composition, energy and density of particles ejected from the target. A one-dimensional heat conduction model is presented to investigate the heating and ablation of a graphite target upon interaction with a polyenergetic electron beam. The effect of electron beam efficiency, power density, accelerating voltage, and Knudsen layer just above the target surface during ablation are taken into account in the model. Phase transition induced during ablation is considered through the temperature dependent thermodynamic properties of graphite. The temperature distribution, surface receding velocity, melting depth, ablation depth, and ablated mass per unit area are numerically simulated. Upon ablation, plasma expansion, induced by interaction of a nanosecond electron beam pulse (~100 ns) with a graphite target in an argon atmosphere at reduced pressure, was investigated by solving gas-dynamics equations. The spatiotemporal profiles of the temperature, pressure, velocity, and density of the plasma plume are numerically simulated for a beam efficiency of 0.6 and accelerating voltage of 15 kV. Each model is validated by comparing some of the obtained simulation results with experimental data available in the literature.Doctor of Philosophy (PhD) in Natural Resources Engineerin

Quantitative risk assessment of a marine riser: an integrated approach

This work presents an integrated risk assessment methodology for structural failure of a marine riser and the consequent release of oil causing ecological risks to marine life. -- A simple, but efficient methodology for fatigue reliability assessment of a vertical top-tensioned rigid riser is proposed. The fatigue damage response is considered as a narrow-band Gaussian stationary random process with a zero mean for the short-term behavior. However, non-linearity in a response associated with Morison-type wave loading is accounted for by using a factor, which is the ratio of expected damage according to a non-linear probability distribution to the expected damage according to a linear method of analysis. Long-term non-stationary response is obtained by summing up a large number of short-term stationary responses. Uncertainties associated with both strength and stress functions of the limit state are quantified by a lognormal distribution. A closed form reliability analysis is carried out, which is based on the limit state function formulated in terms of Miner's cumulative damage rule. The results thus obtained are compared with the well-documented lognormal format of reliability analysis based on time to fatigue failure. The validity of selecting a lognormal hazard rate function for fatigue life is discussed. A Monte Carlo simulation technique is also used as a reliability assessment method. A simple algorithm is used to reduce the large uncertainty associated with direct sampling. Uncertainty arises in the direct sampling technique because of using a small number of simulations in calculating small failure probabilities. A worked example is included to show the practical riser design problem based on reliability analysis. -- As a part of the ecological risk assessment, a fugacity-based methodology is presented to predict the multimedia fate of spilled oil in a marine environment. A level IV (dynamic) fugacity-based methodology coupled with weathering processes is presented. A two-compartment system, comprised of water and sediment, is used to explore the fate of oil. During a spill, oil is entrained into the water column due to natural dispersion, which is considered as the primary input source to the water compartment. Direct input to the sediment compartment is assumed negligible. However, the water column acts as a source to the sediment compartment. Unlike the conventional multimedia modelling approach, the impact area is not predefined; rather the oil slick spreading process determines the contaminated area growth. Naphthalene is used as an indicator for oil. To demonstrate the application of the proposed methodology, simulations for a batch spill scenario of Statfjord oil are also presented. The current study suggests that the water compartment response to the chemical input is faster than the sediment compartment. The major fate processes identified are advection and volume growth in water and sediment, respectively. -- The current study has used the U.S. EPA ecological risk assessment (ERA) framework to estimate the effects on marine life due to underwater release of oil and gas from a broken riser. This approach combines the hydrodynamics of underwater blowout, weathering algorithms, and multimedia fate and transport to measure the exposure concentration. Uncertainties related to multimedia input parameters are incorporated in the analysis. The 95th percentile of the exposure concentration (EC95% ) is taken as the representative exposure concentration (as a conservative value). A bootstrapping method is utilized to characterize EC 95% and associated uncertainty. Toxicity data available in the literature are used to calculate the 5th percentile of the 'predicted no observed effect concentration' (PNEC5% ) using bootstrapping. The risk is characterized based on the cumulative distribution of risk quotient (RQ), which is defined as the ratio of EC 95% , to PNEC5%. -- This thesis describes a probabilistic basis for the ERA, which is essential from risk management and decision making viewpoints. Two case studies of underwater oil and gas mixture release, and oil release with no gaseous mixture, are used to show the systematic implementation of the methodology, elements of ERA, and the probabilistic method in assessing and characterizing the risk

Quantifying particle sorting in microbubble streaming flows

This work seeks to characterize and model the size-dependent behaviour of microparticles in a bubble streaming flow. We show that in microchannels, the steady streaming flow generated by an ultrasonically driven semicylindrical microbubble can be combined with a Poiseuille flow to achieve tunable, high throughput, size-sensitive sorting and trapping of particles much smaller than the bubble itself. We propose a simple geometric mechanism, based on flow speeds and channel geometry, that reliably predicts the sorting behaviour seen in experiment. It is also shown that an asymptotic theory that incorporates the device geometry and superimposed channel flow accurately models key flow features such as peak speeds and particle trajectories. Finally, the forces acting on particles on oscillatory time scales are determined experimentally using a novel method in which the trajectories of small and large particles are compared. These forces are found to scale quadratically with both oscillatory flow speed and particle size. Simulations of particle trajectories are used to show that Saffman lift is not primarily responsible for these forces. Instead, a lubrication theory is proposed that is able to predict both the magnitude and dependence of forces on particles

Development of a coastal fumigation model for continuous emission from an elevated point source and a computer software (Fumig)

A fumigation model based on probability density function (PDF) approach is presented here to study the dispersion of air pollutants emitted from a stack on the shoreline. This work considers dispersion of the pollutants in the stable layer and within thermal internal boundary layer (TIBL) proceeds independently. The growth of TIBL is considered parabolic with distance inland and turbulence is taken as homogeneous and stationary within the TIBL. Dispersion of particles (contaminant) in lateral and vertical directions is assumed independent of each other. This assumption allows us to consider the position of particles in both directions as independent random variables. The lateral dispersion distribution within the TIBL is considered as Gaussian and independent of height. A skewed hi-Gaussian vertical velocity PDF is used to account for the physics of dispersion due to different characteristics of updrafts and downdrafts within TIBL. Incorporating finite Lagrangian time scale for the vertical velocity component, it is observed that it reduces the vertical dispersion in the beginning and moves the point of maximum concentration further downwind. Due to little dispersion in the beginning, there is more plume to be dispersed causing higher concentrations at large distances. The model has considered Weil and Brower's (1984) convective limit to analyze dispersion characteristics within TIBL. The revised model discussed here is evaluated with the data available from the Nanticoke field experiment on fumigation conducted in the summer of 1978 in Ontario, Canada. The results of the revised model are in better agreement with the observed data, as compared to other available models. The study suggests the use of mean absolute error and mean relative error as quantitative measures of model performance along with the residual analysis. For easy and effective use of the newly developed model, user-friendly computer software 'Fumig' is developed in visual basic. Fumig is built upon the developed model and enable easy assessment of concentration profiles under fumigation conditions

PERBANDINGAN ADSORBEN DAUN NIPAH (Nypa fruticans) DAN SERABUT BUAH NIPAH TERHADAP ZAT WARNA METHYLENE BLUE

Nipah atau Nypa fruticans merupakan tumbuhan dengan kandungan selulosa yang cukup besar sehingga bisa digunakan sebagai adsorben. Penelitian ini bertujuan untuk mengetahui perbandingan adsorben daun nipah dan serabut buah nipah terhadap zat warna methylene blue. Proses aktivasi serbuk daun nipah dan serbuk serabut buah nipah dilakukan dengan menggunakan proses maserasi dengan menggunakan pelarut Ethanol p,a. dan HCl 1N. Bahan penyerap yang digunakan pada penelitian ini menggunakan larutan standar methylene blue, sedangkan proses pengukuran panjang gelombang menggunakan alat spektrofotometer UV-Vis. Hasil kalibrasi yang diperoleh dari proses perbandingan adsorben daun nipah dan serabut buah nipah terhadap zat warna methylene blue menggunakan panjang gelombang maksimum 660 nm dengan menggunakan konsentrasi 0,2, 0,4, 0,6, dan 0,8 ppm dimana nilai absorbansi untuk daun nipah dan serabut buah nipah yang  dihasilkan  berbeda,  adapun  nilai  absorbansi  untuk  daun  nipah  yaitu  0,198; 0,203; 0,395; dan 0,407 dan nilai absorbansi untuk serabut buah nipah yaitu 0,096; 0,125; 0,205; dan 0,354. Hasil dari proses pengukuran panjang gelombang di atas menggunakan larutan standar methylene blue dengan adsorben serbuk daun nipah maka nilai absorbansi yang didapatkan yaitu 3,00 ppm, adapun nilai konsentrasi yang didapat ialah 30,29 ppm, sedangkan proses pengukuran panjang gelombang menggunakan larutan standar methylene blue dengan serbuk serabut buah nipah maka nilai absorbansi yang didapatkan yaitu 1,96 ppm, adapun nilai konsentrasi yang didapat ialah 22 ppm. Hasil dari proses perbandingan adsorpsi dari adsorben serbuk daun nipah dan serbuk serabut buah nipah adalah sebagai berikut: 30,29 ppm dan 22 ppm