Novel Method for Assessing Moisture Damage in Asphalt Mixtures

Moisture damage is a major cause of early pavement deterioration and often accelerates other distresses such as rutting, fatigue cracking, and raveling. Water infiltrates into the pavement structure through the cracks and air voids and weakens the adhesive bond between the binder and the aggregates as well as the cohesive bond between the binder particles. Several tests have been adopted to test for moisture susceptibility, most commonly the Modified Lottman (AASHTO, T283) and the Hamburg Wheel Tracking Device (AASHTO, T32404), however, these tests correlate poorly with field results and do not properly replicate the conditions which a pavement structure experiences in the field. Also, the mechanism which determines the mode of failure due to moisture damage, being either adhesive or cohesive, remains largely not understood, and the research tackling this issue is very scarce. The objective of this study is to introduce a new testing procedure based on the pull-off approach and study the factors which influence the mode of failure of the samples, such as the asphalt film thickness and loading rate

Thermal properties of food and pharmaceutical powders

Foods and pharmaceuticals are complex systems usually exposed to various environmental conditions during processing and thus storage, stability, functionality and quality are key attributes that deserve careful attention. The quality and stability of foods and pharmaceuticals are mainly affected by environmental conditions such as temperature, humidity, time, and processing conditions (e.g. shear, pressure) under which they may undergo physical and/or chemical transformations. Glass transition as well as other thermal properties is a key to understand how external conditions affect physical changes of such materials. Development of new materials and understanding the physico-chemical behavior of existing ones require a scientific foundation that translates into safe and high quality foods, improved quality of pharmaceuticals and nutraceuticals with lower risk to patients and functional efficacy of polymers used in food and medicinal products. This research provides an overview of the glass transition and other thermal properties and introduces novel methods developed to characterize such properties

Household food waste generation during COVID-19 pandemic and unprecedented economic crisis: The case of Lebanon

Background: The COVID-19 pandemic has interrupted economies and food systems globally, leading to substantial consequences on food waste, which is also influenced by political and economic factors. To date, information on the attitudes and behaviors of households regarding food waste generation in developing countries like Lebanon, witnessing a multifaceted economic and COVID-19 crisis, is scarce. Previous studies reported that around one third of the food produced in Lebanon gets lost or wasted. This study aims to update the attitudes and behaviors determining household food waste in Lebanon in light of the COVID-19 pandemic and unprecedented economic crisis. Methods: Participants (n = 1251) from the five governorates of the country filled out a structured questionnaire composed of 3 sections and 31 questions. The variable “eat everything prepared” was used as a proxy for food waste. The effects of different socio-behavioral and demographic characteristics on household food waste generation in the country were estimated using a Logistic regression on STATA. Results: Most participants (69%) reported that the economic crisis had a greater impact on their food shopping and eating behaviors compared to the COVID-19 pandemic. In comparison, 65% reported that their household food waste generation did not change because of the COVID-19 pandemic, and 47% reported that their household food waste generation decreased because of the economic crisis. Employment status, income, educational level, and the number of householders did not affect food waste generation. Feelings of guilt, thinking of ways to use leftovers, and frequent preparation of more dishes were negatively associated with food waste generation while eating out and buying special offers showed the opposite effect. Conclusion: Our findings provide a better understanding of more effective community-based food waste-related interventions in Lebanon. Future research is still needed to explain the medium and long-term effects of COVID-19 and the economic crisis on food waste-related behaviors in the country since the behavioral changes uncovered in the current study might be temporary during the pandemic and the economic crisis and not permanent. This issue should be verified in the future using longitudinal surveys

Persistent Organic Pollutants in Human Milk: Exposure Levels and Determinants among Lactating Mothers in Lebanon

ABSTRACT: Exposure of newborns to persistent organic pollutants (POPs) is a public health concern. The objective of this study was to assess the prevalence of POPs in human milk collected from lactating mothers in Lebanon and to investigate the sociodemographic, nutritional, and other lifestyle determinants. Fifty-four breast milk samples were collected as per World Health Organization guidelines. A survey was used to assess the anthropometric and demographic characteristics of participants. Dietary habits were evaluated based on a semiquantitative food frequency questionnaire. Organochlorine pesticides and polychlorinated biphenyls were measured in milk samples with liquid-liquid extraction and gas chromatography. Among the screened POPs, dichlorodiphenyldichloroethylene (DDE) was the only POP detected in breast milk samples and was found in only 17.9% of the samples, with a mean (SD) of 11.6 (5.0) μg/L and a range of 5.7 to 21.4 μg/L. Prepregnancy body mass index and age were positively associated with DDE contamination in breast milk. Women who consumed cereals at least two times per week had detectable DDE contamination in their breast milk. Consumption of potatoes and beans at least once per week was also associated with DDE contamination. Our study is the first to assess the presence of POPs in breast milk in Lebanon. The benefits of breastfeeding compensate for the low prevalence of DDE in the breast milk. Our findings highlight the high need to implement monitoring policies, good agricultural practices, and education programs for breastfeeding mothers.This project was supported by the Graduate Studies and Research Office, Lebanese American University