3-Hydroxy coumarin demonstrates anti-biofilm and anti-hyphal efficacy against Candida albicans via inhibition of cell-adhesion, morphogenesis, and virulent genes regulation.

Candida albicans, a common fungus of human flora, can become an opportunistic pathogen and causes invasive candidiasis in immunocompromised individuals. Biofilm formation is the prime cause of antibiotic resistance during C. albicans infections and treating biofilm-forming cells is challenging due to their intractable and persistent nature. The study intends to explore the therapeutic potential of naturally produced compounds by competitive marine bacteria residing in marine biofilms against C. albicans biofilm. To this end, 3-hydroxy coumarin (3HC), a compound identified from the cell-free culture supernatant of the marine bacterium Brevundimonas abyssalis, was found to exhibit anti-biofilm and anti-hyphal activity against both reference and clinical isolates of C. albicans. The compound demonstrated significant inhibitory effects on biofilms and impaired the yeast-to-hyphal transition, wrinkle, and filament morphology at the minimal biofilm inhibitory concentration (MBIC) of 250 µg mL-1. Intriguingly, quantitative PCR analysis of 3HC-treated C. albicans biofilm revealed significant downregulation of virulence genes (hst7, ume6, efg1, cph1, ras1, als1) associated with adhesion and morphogenesis. Moreover, 3HC displayed non-fungicidal and non-toxic characteristics against human erythrocytes and buccal cells. In conclusion, this study showed that marine biofilms are a hidden source of diverse therapeutic drugs, and 3HC could be a potent drug to treat C. albicans infections.

Evaluating overtaking and filtering maneuver of motorcyclists and car drivers using advanced trajectory data analysis.

The present paper compares motorized two-wheeler (MTW) and passenger car's interactions with the rest of the traffic in urban roads while performing overtaking and filtering maneuvers. To better understand filtering maneuvers of motorcyclists and car drivers, an attempt was made to propose a new measure, i.e. pore size ratio. Additionally, the factors affecting lateral width acceptance for motorcyclists and car drivers while overtaking and filtering were studied using advanced trajectory data. A regression model was developed to predict the significant factors affecting motorcyclist's and car driver's decisions to accept lateral width with the adjacent vehicle while performing overtaking and filtering maneuvers. Finally, a comparative analysis between machine learning and the probit model revealed that, in the present case, machine learning models perform better than the probit model in terms of the model's discernment power. The findings of this study will help ameliorate the power of existing microsimulation tools.

Examining risky riding behavior in India using Motorcycle rider behavior questionnaire.

Powered two-wheelers (PTW) constitute the most vulnerable type of road user, primarily due to their lack of protection compared to other motorized vehicles, which can lead to a severe accident in the event of crashes. A notable increase in the percentage of PTW accidents resulting in fatalities has raised a serious need for further research in understanding riding behavior. The Motorcycle rider behavior questionnaire (MRBQ) based studies have shown promising results by using MRBQ to relate riding behavior with crash risk. Despite numerous studies using the MRBQ technique and inconsistency in derived inferences across the studies highlighted the need to revise MRBQ and carry out predictive validity for capturing the correct riding behavior of Indian riders. Therefore, this research modified the previously available questionnaire by considering the focus group's opinion, consisting of twenty professional riders, two transportation experts, and two traffic police officers. Additionally, the predictive validity check of MRBQ was carried out using a sample of Indian riders consisting of 392 participants. The exploratory factor analysis of the MRBQ revealed a 32 item version of the questionnaire divided into a four-factor structure (traffic errors, control errors, speed violations, and stunts). The present research highlighted some critical dissimilarities between PTW riders of India and other countries. The low mean score (based on the Likert scale) of the items under the four-factor structure indicated overall a safe PTW rider behavior of Indian riders. Among the four factors, speed violation showed the highest mean score and stunts showed the least mean score indicating frequent and infrequent aberrant ridding behaviors, respectively. A known group construct validity check revealed that gender had a significant and age an insignificant effect on the reporting of aberrant riding behaviors. Furthermore, a negative binomial regression analysis revealed that traffic error had the highest incidence rate ratio, confirming it to be the most significant predictor of crash risk for Indian riders. Finally, the study briefly discussed counter-measure strategies targeting specific riding behavior.

Comparative evaluation of bond strength of all-metal crowns with different luting agents after undergoing various modes of surface treatments: An in-vitro study.

AIM: This study includes a comparative evaluation of the various surface treatments of the intaglio surface of crowns in combination with various luting agents for maximal retention. MATERIALS AND METHODS: Totally, 150 dies of a standard complete crown preparation were fabricated. Wax pattern with a loop on the occlusal surface was prepared on each die using standard procedures, and then crowns were cast with nickel-chromium alloy. These crowns were randomly divided into five groups as per the surface of the intaglio surface of the metal copings. The crowns in each group were again subdivided randomly into three groups as per the luting agents used resin-modified glass ionomer cement, glass ionomer cement, and zinc phosphate cement. Retention was measured (MPa) by separating the metal crowns from the metallic die under tension on a Universal testing machine. STATISTICAL ANALYSIS USED: The data were recorded and statistically analyzed using one-way analysis of variance followed by Tukey's test. RESULTS: The retention differed both with surface treatment and type of luting agents. Untreated group showed the least bond strengths < sandblasting with 50 µm alumina < sandblasting with 50 µm alumina with ultrasonic cleaning < sandblasting with 110 µm alumina < sandblasting with 110 µm alumina along with ultrasonic cleaning. For luting agents, glass ionomer cement showed least bond strength because there was no chemical bonding present between metal crown and metallic die, followed by zinc phosphate cement and maximum bond strength were found for resin-modified glass ionomer cement. CONCLUSION: Among all types of surface treatments used in this study, maximum bond strength was yielded by sandblasting with 110 µm alumina + ultrasonic cleaning and the best luting agent was resin-modified glass ionomer cement.