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This research explores how filamentary objects behave when they collapse in the presence of exotic material. To accomplish this, we employ Palatini (R, T) theory as a candidate for exotic material. We derive the collapsing equation by enforcing the Darmois junction condition on the collapsed surface boundary. At this boundary, we obtain that the radial pressure is proportionate to the time‐dependent term of the field and is not zero. Lastly, we investigate the correlation between dark matter and gravitational waves and find that exotic terms disrupt the transmission of gravitational waves. It is worthwhile to mention here that our results (in both formalisms, metric approach and Palatini approach) reduce to (R) gravity and general relativity. [ABSTRACT FROM AUTHOR]

BACKGROUND: Ultraviolet Radiation (UVR) from the sun is a significant environmental component that impacts on human health. Excessive UVR exposure has immediate impacts like burning and tanning, as well as long-term consequences including skin damage, photo-aging, skin malignancies. The objective for this study is to determine the student's knowledge, attitude and practice regarding solar ultraviolet exposure in Karachi, Pakistan. METHODS: A cross-sectional study was done in Public Sector University; total 361 students were recruited through stratified cluster sampling from different colleges of university. Data collection was done by validated structured questionnaire. Logistic regression was used to determine the association of outcome variables with risk factors and p-value of <0.05 as a threshold of statistical analysis. RESULTS: Most of the students were appropriate knowledge (71%), positive attitude (51%) and safe practice (54%) regarding ultraviolet solar exposure. Almost half (69%) of participants were used sun protective agents. After adjustment of covariate, female gender (OR 2.20 (95% CI 1.29-4.07) (p-value 0.004), significantly associated with in-appropriate knowledge, third year students (OR 2.93 (95% CI 1.01-8.95) p-value 0.048) were significantly associated with negative attitude. Age group 18-21 years (OR 1.75(95% CI 1.43-5.31) p-value 0.003) were significantly associated with un-safe practice regarding solar ultraviolet exposure harmful effects. CONCLUSION: This study found that knowledge level was appropriate but attitude and practice level need to improve for prevention of harmful effects of solar ultra violet ray exposure. The study encourages students to be more aware of sun protection behavior in order to avoid the long-term effects of sun exposure. [ABSTRACT FROM AUTHOR]

Private information puts naïve traders at a significant trading disadvantage and at the same it provide crucial signals managers for investment adjustment. These two forces have opposing effects on the cost of equity, and the overall effect is determined by which force dominates. For clinching this effect, this study finds out how investment adjustment plays the moderating role between private information and COE. The study employs data of non-financial firms listed on PSX from 2008 to 2019. Further, the study employs a two-step system GMM dynamic panel estimator to analyze the data. The findings of the study show that companies with a low investment adjustment flexibility known as "value firms" do not gain as much from information incorporated in market prices compared to firms having high flexibility in adjusting investment "growth firms." This study adds to the literature by revealing unique insight on the effect of investment adjustment in reducing the influence of private information on COE and corporate investment as well. JEL classification: D82, G14, G410. [ABSTRACT FROM AUTHOR]

Customers have a tendency of need for confirmation when it comes to product quality and its features so that they are able to get maximum benefits for their money, there is an automatic cost and benefit analysis going on in the mind of the customers while selecting the product. Online testimonials are the most convenient source of fulfilling that need for confirmation which either make a customer trust a brand or vice versa. This study explores the role of online testimonials when it comes to brand trust, it strives to explore various aspects of the online testimonials which contribute in the pre-purchase phase perceptual development of the customer, furthermore Expectancy disconfirmation model was utilized as a theoretical foundation. Data was collected through semi-structured In-depth interviews which were taken from habitual online shoppers of Karachi. The data was analyzed through Nvivo to identify codes, from the codes, categories were extracted, and the categories were refined to extract final themes. The paper identifies certain the tendency of the role of online testimonials when it comes to brand trust along with some elements of online testimonials that customer deems important for decision making. [ABSTRACT FROM AUTHOR]