490 research outputs found
A study on anatomical dimensions of bronchial tree
Background: The principle of minimal work requires that the conducting airways of human lungs should have a maximum radius for minimal resistance to gas flow. Malphigi et al said that the trachea terminated in dilated vesicle. The study of bronchial tree and their dimensions is useful in various aspects as to know the entry of foreign particles, to maintain posture for patients suffering from suppurative lung disorders. For anaesthetist to know the caliber of trachea for intubation, bronchoscopy. Bronchial anatomy is essential knowledge for thoracic surgeons in various surgical maneuvers.Methods: The study of bronchial tree is done in 20 pairs of lungs and the following are observed. Various dimensions like tracheal length, width, sub carinal angle, Length and diameter of principal bronchi from the level of bifurcation of trachea is noted with digital Vernier calipers and scale.Results: Though dimensional analysis of bronchi was studied, it shows no significance from earlier studies. In the present study all the dimensions are within normal limits. Out of 20 pairs 6 specimens showed variations in the branching patterns.Conclusions: The results suggests that there are limited variations in the dimensional study, now a days bronchoscopy procedures are widely used in diagnostic and therapeutic purposes. The sub carinal angle indirectly helps in diagnosis of cardiovascular problems and for surgical resection of segments
Why workers disengage? Factors from âHeadâ or âHeartâ to be tagged on?
Oil palm plantations are decisively situated in the various regions of Malaysia where the climatic conditions are appropriate for planting oil palm. One cannot compare the work environment of such plantations with normal office settings.The workers in those plantations are working in remote locations, totally cut off from the other part of the world. Majority workers are from Indonesia, Philippines like low income countries.The work environment is physically demanding and challenging to the workers due to many factors. An exploratory study has conducted on employee disengagement in the oil palm plantations in the Sabah region of Malaysia.The study has taken up employee disengagement factors due to the lack of interest among the local people to engage themselves in the oil palm plantations work and the plantation industry in Malaysia is facing an acute labor shortage to carry forwards the oil palm business.The study follows, field visits, interviews with the workers, focus group discussions and specifically Delphi.The findings supported to identify the 7 factors coming under
the theme employee disengagement as Wage and Welfare, Work Environment, Lack of Safety and security, Poor Organizational Support, Rigid Rules and regulations, and Lack of individual motivation.The study paves better insight to lead this qualitative research in an organized quantitative research
Changes in the ducts of the glands of the hard palate in reverse smokers
Three hundred fifty-nine cases of stomatitis nicotina were studied in reverse smokers of home made chuttas. One hundred thirty-five biopsies of papular unbilicated lesions of stomatitis nicotina were studied histopathologically. The biopsies were chosen after toluidine blue staining. Mild dysplastic to severe dysplastic changes were seen around the openings of the ducts of the glands. There were three cases of microinvasive carcinoma in the one hundred thirty-five biopsies. Cystic dilatation of the ducts, due to obstruction of the ducts by keratotic plugging, was not seen in stomatitis nicotina lesions but was seen in elderly women who had smoked reverse for more than 4 to 5 decades. The ducts of the glands could probably form a portal of entry for the tobacco pyrolytic products which may act as carcinogenics
Nicotine stomatitis and its relation to carcinoma of the hard palate in reverse smokers of chuttas
Clinical surveys and biopsy studies demonstrated a close correlation among reverse smoking, nicotine stomatitis, and carcinoma of the palate
Dynamics of parasite population and its histopathological and histophysiological effects in the stomach of a freshwater fish
The caryophyllaeid cestode Lytocestoides fossilis infects the freshwater catfish Heteropneustes fossilis. The study was conducted for two consecutive years (2004-06) to record the bio-statistical data of the parasite. The incidence, intensity, density and index of infection of the parasite have been recorded. The infection was more during June to September, moderate during February to May and low during October to January. The parasite brought about severe histopathological changes in the stomach of infected fish. The changes observed in the stomach of fish included structural damage of the villi, inflammation, and fibrosis associated with hyperplasia and metaplasia. The hypertrophy of mucous layer led to vacuolation and necrosis. Histochemical changes were noticed with enhanced carbohydrate, protein and lipid contents. The enhanced substrate content in the infected organ might be due to the disfunctioning of the digestive tract, which results in the accumulation of various metabolites. Mucus secretion was triggered as a protective interaction against parasitic invasion. The parasitic infection affects the general metabolic state of the host and as the result, the fish becomes sluggish and moribund
Histopathological Study of Stomatitis Nicotina
One hundred and thirteen biopsies of the palate in people accustomed to smoking cigars, most of them with the burning end of the cigar inside the mouth, have been studied
New blasting techniques for productivity enhancement in underground coal mines
The pace of developments in underground blasting technology is insignificant in contrast to developments in opencast blasting. Blasting practices in underground mine s has limited flexibility due to many safety criteria, statutory and field constraints. This has narrowed the scope of major modifications in the solid blasting design vis-Ă -vis the efficiency and yield per round. However, it is high time to balance the opencast and underground mine production, in view of the exhausting reserves in shallow depth and socio-environmental problems due to opencast mining. With this back-drop, Central Institute of Mining & Fuel Research (CIMFR), Regional Centre, Nagpur developed two new underground blasting techniques with simple modifications in explosive loading patterns. They are: (i) in-hole delay solid blasting technique was in-hole delay solid blasting technique by inserting multiple delay detonators in cut holes to improve the solid blasting efficiency. The conventionally available resources are used in this technique without violating the statutory guidelines. The trial blast results indicated improvements in all the parameters like pull, yield per round, powder factor and detonator factor. The overall improvement in pull per round was 49% with 1.5m deep rounds and 40% with 1.8m deep rounds. The technique also resulted in reduction of ground vibration intensity by 32-37%.
Another blasting method developed was bottom hole decking technique by inserting air-deck at the bottom of the blast holes. In this technique a spacer is to be placed at the bottom of the hole and remaining portion of the hole is conventionally charged. The length of spacer is equal to 10-12% of depth of blasthole.
A wooden spacer or any antistatic plastic pipe can also be used for decking. The technique was also applied in both soft and medium hard coal formations while exploiting the thin coal seams. The trial blast results indicated improvements in pull, yield per round and powder factor. The overall progress/pull per round observed was 36% with 1.5m deep rounds and it was up to 22%was 1.8m deep rounds with the powder factor (ton/kg) improvement up to 70%. The technique was also result in reduction of ground vibrations by 20-26%. The experimental results also reveal that the in-hole delay solid blasting and bottom hole decking techniques are suitable for relatively harder and softer formations respectively for improving blasting productivit
Effect of repeated blast Vibrations on damage intensity of granitic rock mass at an hydroelectric Construction project
Rock blasting induced ground vibrations produce deformations in the vicinity of blasting site. The effect of blast loading on structures is a growing concern of safety and stability. Extensive data are available on the behavior of surface structures subjected to blast vibrations. However, only limited information is available on the effect of blast induced dynamic forces on the underground opening like tunnels and caverns. The reported findings state that blast induced dynamic stress, one or several cycle of repeated strains may cause deterioration in the rock mass or create damage to the dam foundation. This paper deals with the research work carried out at jurala hydroelectric power project (JHPP) on the effect of repeated blast vibrations on powerhouse foundation in a jointed rock mass. The damage caused by blast induced vibrations can be categorized in to two types: (i) near-field damage due to high frequency vibrations when blast is occurring in the close proximity and (ii) far-field damage due to low frequency vibrations when the blast is occurring relatively farther distance. The near-field damage was assessed by monitoring ballast vibrations and borehole camera inspection survey. The far field damage was assessed by continuous monitoring of vibrations, borehole camera inspection survey and P-wave velocity measurement by ultrasonic testing machine. Borehole camera was used to examine the crack extension and damage inspection of rock mass. This paper reveals that repeated dynamic loading imparted on the jointed rock mass from subsequent blast, in the vicinity, resulted in damage even at 22% of critical peak particle velocity (Vmax). The far-field damage due to the repeated blast loading of 40-45 rounds was more than 77% of he near-field damage. The results of the experimental study indicated that vibration levels, even at less than critical Vmax, can cause safety and stability problems to the structures in /on joined rock mass, when exposed to the repeated blast loading. This paper stresses the need for consideration of the effect of repeated blast loading in fixing the threshold limits of Vmax to avoid far-field damage
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Eye movements and reading in glaucoma: observations on patients with advanced visual field loss
Purpose To investigate the relationship between reading speed and eye movements in patients with advanced glaucomatous visual field (VF) defects and age-similar visually healthy people. Methods Eighteen patients with advanced bilateral VF defects (mean age: 71, standard deviation [SD]: 7 years) and 39
controls (mean age: 67, SD: 8 years) had reading speed measured using short passages of text on a computer set-up incorporating eye tracking. Scanpaths were plotted and analysed from these experiments to derive measures of âperceptual spanâ (total number of letters read per number of saccades) and âtext saturationâ (the distance between the first and last fixation on lines of text). Another eye movement measure, termed âsaccadic frequencyâ (total number of saccades made to read a single word), was derived from a separate lexical decision task, where words were presented in isolation. Results Significant linear association was demonstrated between perceptual span and reading speed in patients (R2=0.42) and controls (R2=0.56). Linear association between saccadic frequency during the LDT and reading speed was also found in patients (R2=0.42), but not in controls (R2=0.02). Patients also exhibited greater average text saturation than controls (P=0.004). Conclusion Some, but not all, patients with advanced VF defects read slower than controls using short text passages. Differences in eye movement behaviour may partly account for this variability in patients. These patients were shown to saturate lines of text more during reading, which may explain previously-reported difficulties with sustained reading
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