A study on male homosexual behavior.

INTRODUCTION: Male homosexual behavior carries a high risk of transmitting sexually transmitted infections (STIs). Ignorance regarding the associated high risk, indulgence inspite of no natural homosexual orientation and not using protective barrier methods can affect the sexual health of adolescents and adults. AIM: (1) To assess the proportion of men who have sex with men (MSM) having a natural homosexual orientation compared to those who had acquired the homosexual behavior initially under various circumstances (such as due to certain misconceptions, fear of having heterosexual contact, peer pressure, and influence of alcohol). (2) To assess the level of awareness regarding increased risk of transmission of STIs associated with homosexual behavior and regarding protective barrier methods. MATERIALS AND METHODS: After obtaining consent from the subjects, questionnaire - based interview used for obtaining data for this observational (cross-sectional) study. RESULTS: (1) Of the 50 subjects, only about 25% had interest in homosexual behavior prior to initial episode. (2) About 50% subjects indulged in homosexual behavior due to lack/fear of having heterosexual contact. (3) About 60% subjects believed that homosexual behavior carried relatively lower risk of acquiring STIs and 68% subjects have had unprotected contact. (4) About 70% subjects had only acquired this behavior and nearly 60% subjects were interested in heterosexual marriage and not interested in further homosexual behavior. CONCLUSION: (1) Homosexuality is a natural orientation in some and an acquired behavior in the rest. (2) If homosexual behavior is acquired, due to misconceptions, then imparting sex education and awareness regarding involved risks, and the importance of protective barrier methods will prevent ignorance driven behavior. For those with natural homosexual orientation, the importance of protective barrier methods in homosexual behavior needs emphasis.

Seborrheic keratosis over genitalia masquerading as Buschke Lowenstein tumor.

Seborrheic keratosis (SK) is a common benign condition of the skin. It does not usually appear before middle age. Upper trunk and face are the sites most commonly involved. Lesions are also frequently seen on the extremities. SK of the genitalia is a rare entity. It has been frequently mistaken as genital warts and differentiation is made only on histopathology. We report a case of SK with polypoidal lesions restricted to the skin on and around the genitalia since 10 years. SK should be considered in the differential diagnosis of pedunculated lesions of the penis. The histopathology after shave excision is diagnostic.

Estimation of scattered radiation in digital breast tomosynthesis.

Digital breast tomosynthesis (DBT) is a promising technique to overcome the tissue superposition limitations found in planar 2D x-ray mammography. However, as most DBT systems do not employ an anti-scatter grid, the levels of scattered radiation recorded within the image receptor are significantly higher than that observed in planar 2D x-ray mammography. Knowledge of this field is necessary as part of any correction scheme and for computer modelling and optimisation of this examination. Monte Carlo (MC) simulations are often used for this purpose, however they are computationally expensive and a more rapid method of calculation is desirable. This issue is addressed in this work by the development of a fast kernel-based methodology for scatter field estimation using a detailed realistic DBT geometry. Thickness-dependent scatter kernels, which were validated against the literature with a maximum discrepancy of 4% for an idealised geometry, have been calculated and a new physical parameter (air gap distance) was used to estimate more accurately the distribution of scattered radiation for a series of anthropomorphic breast phantom models. The proposed methodology considers, for the first time, the effects of scattered radiation from the compression paddle and breast support plate, which can represent more than 30% of the total scattered radiation recorded within the image receptor. The results show that the scatter field estimator can calculate scattered radiation images in an average of 80 min for projection angles up to 25° with equal to or less than a 10% error across most of the breast area when compared with direct MC simulations.

Simulation and assessment of realistic breast lesions using fractal growth models.

A new method of generating realistic three dimensional simulated breast lesions known as diffusion limited aggregation (DLA) is presented, and compared with the random walk (RW) method. Both methods of lesion simulation utilize a physics-based method for inserting these simulated lesions into 2D clinical mammogram images that takes into account the polychromatic x-ray spectrum, local glandularity and scatter. DLA and RW masses were assessed for realism via a receiver operating characteristic (ROC) study with nine observers. The study comprised 150 images of which 50 were real pathology proven mammograms, 50 were normal mammograms with RW inserted masses and 50 were normal mammograms with DLA inserted masses. The average area under the ROC curve for the DLA method was 0.55 (95% confidence interval 0.51-0.59) compared to 0.60 (95% confidence interval 0.56-0.63) for the RW method. The observer study results suggest that the DLA method produced more realistic masses with more variability in shape compared to the RW method. DLA generated lesions can overcome the lack of complexity in structure and shape in many current methods of mass simulation.

Computer design synthesis of a below knee-Syme prosthesis.

A detailed design synthesis analysis of the BK Syme prosthesis is provided, to determine the socket's cutout orientation size and shape, cutout fillet shape, socket wall thickness distribution and the reinforced fiber distribution in the socket wall, for a minimally stressed structurally safe lightweight prosthesis. For analysis purpose, the most adverse socket loading is obtained at the push-off stage of gait; this loading is idealised as an axial in-plane loading on the bottom edge of the circular cylindrical socket shell whose top edge is considered fixed. Finite element stress analysis of the socket shell (with uniform and graded wall thickness) are performed for various orientations of the cutout and for various types of corner fillets. A lateral cutout with a streamline fillet is recommended. The wall material (i.e., thickness) distribution is determined so as to minimise the stresses, while ensuring that the wall material's stress limits are not exceeded. For such a maximally-stressed lightweight socket shell, the panels in the neighbourhood of the cutout are checked to ensure that they do not buckle under their acquired stresses. A fiber-reinforced laminated composite socket shell is also analysed, to recommend optimum variables in orientations and densities of reinforcing fibers.