Mathematical analysis of corneal oxygenation

Purpose: To develop a quasi steady state model for the time course concentration profile describing the oxygen diffusion and consumption in a multilayered corneal tissue and investigate the effect of various model parameters on the oxygen concentration for open and closed eyes. Method: A simple mathematical model for the oxygen transport in multilayered corneal tissue was developed using Fick’s law of diffusion and Michaelis-Menten kinetics of metabolism. A Crank-Nicoloson finite difference scheme of the equation describing the oxygen diffusion and consumption was written, in which spatial diffusive terms were approximated by central differences while the temporal terms were approximated by average of forward and backward time differences. A system of linear equations obtained from the Crank-Nicholoson finite differences schemes was solved by the Thomos Algorithm. Result: The model predict that oxygen tension without contact lens for an open and closed eye increases along the distance from the aqueous side in each of the layers and the partial pressure gradient in the stroma is higher than that in the epithelium and endothelium layers. It is also observed that the oxygen tension with contact lens in the steady and transient stares, in case of low oxygen permeability of lens decreases along the distance from the aqueous side to the stroma, whereas, at higher oxygen permeability of the lens it increases along the distance for open and closed eyes. Conclusion: Oxygen tension as observed in the cornea of an open eye with or without contact lens is higher than that in closed eye. Also at a high oxygen permeability of contact lens enhance the oxygen tension significantly than that of low oxygen permeability. Keywords: Oxygen transport, finite difference, metabolism, oxygen consumption, pressure gradient

A non destructive method to detect the incipient fault in rolling element bearing

It is essential to have prior warning of incipient fault (s) in any critical equipment occurring due to vibration. Vibration monitoring is good nondestructive technique to detect the fault of machines at an early stage. Capturing vibration signature of machines at slow speed is a difficult task due to impact of low energy, mostly absorbed by the structural path and falls much below the cut off frequency of the normally available accelerometer. To resolve the issue, a systematic proce-dure has been developed. It has the facility to break the signal in different level, envelope capturing and finally convert to frequency spectrum. The system has been tested under various operating condition that suits to industry to diagnose the problem of bearing. The method can predict the problem very well at its inception

Evaluation and diversity analysis in Indian mustard [Brassica juncea (L.) Czern & Coss.] germplasm accessions on the basis of principal component analysis

Principal component analysis was carried out with 20 morphological traits (including quantitative as well as qualitative) among 96 germplasm lines of Indian mustard [Brassica juncea (L.) Czern & Coss.]. Principal factor analysis led to the identification of eight principal components (PCs) which explained about 70.41% variability. The first principal component (PC1) explained 16.21% of the total variation. The remaining PC’s explained progressively lesser and lesser of the total variation. Varimax Rotation enabled loading of similar type of variables on a common principal factor (PF) permitting to designate them as yield factor, maturity factor and oil factor etc. Based on PF scores and cluster mean values the germplasm accessions viz., RC2, RC32 and RC51 (cluster I), RC95 and RC96 (cluster X) were found superior for seed yield/plant and yield related factors like primary and secondary branches/plant; while the accessions RC34, RC185 and RC195 (cluster III) and RC53 (cluster VIII) were found superior for oil content. These accessions may further be utilized in breeding programmes for evolving mustard varieties having high seed yield and oil content. Hierarchical cluster analysis resulted into ten clusters containing two to 26 accessions. The results of cluster and principal factor analyses were in confirmation of each other

Genetics of earliness in fenugreek under powdery mildew inoculated and natural environments

Inheritance of days to flower and maturity in fenugreek (Trigonella foenum-graecum L.) was studied using six generations (P1, P2, FI, F2, B1 and B2) of a cross between HM 350 (early) and HM65 (late) in two different environments ie. inoculated with conidia of powdery mildew disease (E1) and normal (E2). Partial dominance was observed for both the traits under both the environments. The variances of F2 and backcross generations revealed the predominance of non-additive gene action. Genetic analysis suggested that generally all types of epistatic effects were significant for both the traits studied in one environment or another. Intermating of selects in early generations has been suggested for further improvement in these traits. &nbsp

Utilizing geospatial information to implement SDGs and monitor their Progress

It is more than 4 years since the 2030 agenda for sustainable development was adopted by the United Nations and its member states in September 2015. Several efforts are being made by member countries to contribute towards achieving the 17 Sustainable Development Goals (SDGs). The progress which had been made over time in achieving SDGs can be monitored by measuring a set of quantifiable indicators for each of the goals. It has been seen that geospatial information plays a significant role in measuring some of the targets, hence it is relevant in the implementation of SDGs and monitoring of their progress. Synoptic view and repetitive coverage of the Earth's features and phenomenon by different satellites is a powerful and propitious technological advancement. The paper reviews robustness of Earth Observation data for continuous planning, monitoring, and evaluation of SDGs. The scientific world has made commendable progress by providing geospatial data at various spatial, spectral, radiometric, and temporal resolutions enabling usage of the data for various applications. This paper also reviews the application of big data from earth observation and citizen science data to implement SDGs with a multi-disciplinary approach. It covers literature from various academic landscapes utilizing geospatial data for mapping, monitoring, and evaluating the earth's features and phenomena as it establishes the basis of its utilization for the achievement of the SDGs

Dehairing Australian alpaca fibres with a cashmere dehairing machine

Many classes of alpaca fibres contain a certain amount of coarse fibres, which are strong and stiff, and cause discomfort to the end users of the alpaca fibre products. It is therefore desirable to separate the coarse fibres from the fine alpaca fibres. This paper reports trial results on alpaca dehairing using a cashmere dehairing machine. The diameters of alpaca fleece, dehaired alpaca fibres and removed alpaca fibres were analysed, and the fibre lengths before and after dehairing have been compared. The results indicate that it is feasible to dehair alpaca fibres using a cashmere dehairing facility. The dehaired alpaca fibres are cleaner, bulkier and softer, with around 1.5 &mu;m reduction in average fibre diameter, but the dehairing process shortens the dehaired fibre length considerably. The dehairing effectiveness of coarse fibre removal using the cashmere dehairing technology has also been discussed in this paper. <br /

Use of Water Balance and Tracer-Based Approaches to Monitor Groundwater Recharge in the Hyper-Arid Gobi Desert of Northwestern China

The groundwater recharge mechanism in the hyper-arid Gobi Desert of Northwestern China was analyzed using water balance and tracer-based approaches. Investigations of evaporation, soil water content, and their relationships with individual rainfall events were conducted from April to August of 2004. Water sampling of rainwater, groundwater, and surface water was also conducted. During this period, 10 precipitation events with a total amount of 41.5 mm, including a maximum of 28.9 mm, were observed. Evaporation during the period was estimated to be 33.1 mm. Only the soil water, which was derived from the heaviest precipitation, remained in the vadose zone. This is because a dry surface layer, which was formed several days after the heaviest precipitation event, prevented evaporation. Prior to that, the heaviest precipitation rapidly infiltrated without being affected by evaporation. This is corroborated by the isotopic evidence that both the heaviest precipitation and the groundwater retained no trace of significant kinetic evaporation. Estimated δ-values of the remaining soil water based on isotopic fractionation and its mass balance theories also demonstrated no trace of kinetic fractionation in the infiltration process. Moreover, stable isotopic compositions of the heaviest precipitation and the groundwater were very similar. Therefore, we concluded that the high-intensity precipitation, which rapidly infiltrated without any trace of evaporation, was the main source of the groundwater