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An integrated socio-economic agent-based modeling framework towards assessing farmers’ decision making under water scarcity and varying utility functions
Get PDFA spatio-temporal Agent Based Modeling (ABM) framework is developed to probabilistically predict farmers' decisions concerning their future farming practices when faced with potential water scarcity induced by future climate change. The proposed framework forecasts farmers' behavior assuming varying utility functions. The functionality of the proposed ABM is illustrated in an agriculturally dominated plain along the Eastern Mediterranean coastline. The model results indicated that modelling farmers as agents, who were solely interested in optimizing their agro-business budget, was only able to reproduce 35% of the answers provided by the farmers through a administered field questionnaire. Model simulations highlighted the importance of representing the farmers' combined socio-economic attributes when assessing their future decisions on land tenure. This approach accounts for social factors, such as the farmers' attitudes, subjective norms, social influence, memories of previous civil unrest and farming traditions, in addition to their economic utility to model farmer decision making. Under this scenario, correspondence between model simulations and farmers' answers reached 95%. Additionally, the model results show that when faced with the negative impacts of climate change, the majority of farmers seek adaptive measures, such as changing their crops and/or seeking new water sources, only when future water shortages were predicted to be low to moderate. Most opt to cease farming and allow their lands to urbanize or go fallow, when future water shortages were predicted to be high. Meanwhile, incorporating and modeling the social influence structures within the ABM diminished farmers' willingness to adapt and doubled their propensity to sell or quit their land. The proposed framework is able to account for a variety of utility functions and to successfully capture the actions and interactions between farmers and their environment; thus, it represents an innovative modeling approach for assessing farmers’ behavior and decision-making in the face of future climate change. The nonspecific structure of the framework allows its application at any agriculturally dominated setting facing future water shortages promulgated by a changing climate. © 2022 Elsevier Lt
Analyzing eutrophication and harmful algal bloom dynamics in a deep Mediterranean hypereutrophic reservoir
Get PDFExcessive point and non-point nutrient loadings accompanied with elevated temperatures have increased the prevalence of harmful algal bloom (HAB). HABs pose significant environmental and public health concerns, particularly for inland freshwater systems. In this study, the eutrophication and HAB dynamics in the Qaraoun Reservoir, a hypereutrophic deep monomictic reservoir suffering from poor water quality, were assessed. The reservoir was mostly phosphorus limited, and large algal particulates dominated light attenuation in the water column. During bloom events, surface chlorophyll-a concentrations increased up to 961.3 µg/L, while surface concentrations of ammonia and ortho-phosphate were rapidly depleted; surface dissolved oxygen reached supersaturation levels and surface pH levels were up to 3 units higher than those measured in the hypolimnion. Meanwhile, measured Microcystin-LR toxin concentrations in the reservoir exceeded the World Health Organization 1 μg/L provisional guideline 45% of the times. Yet, the results showed that most of the toxins were intra-cellular, suggesting that they decayed rapidly when released into the reservoir. Results from a random forests ensemble model indicated that tracking the changes in surface dissolved oxygen levels, ammonium, ortho-phosphate, and pH can be an effective program towards predicting the reservoir’s trophic state and algae blooms. © 2022, The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature
A NEW LAYER OF REFUGEE POLITICS AT UNHCR BIOMETRIC TECHNOLOGY: SYRIAN REFUGEE BIOMETRIC REGISTRATION BY UNHCR IN LEBANON
Get PDFOver the past decade, biometric technology has started to emerge as a component of the politics of empowerment, notably in international aid situations like UNHCR. Considering, the development of digitalized, biometric refugee data adds a new layer of complexity to UNHCR's already problematic relationship with the host state. Hence, this thesis intends to provide a detailed descriptive analysis on the landscape of UNHCR's biometric registration operation in response to the Syrian crisis in Lebanon. In addition, I analyze the data-sharing discussion between UNHCR and Lebanon while reflecting on the political climate in Lebanon. As a methodology, I review pertinent academic publications, policies, news pieces, and publications on reports that look at biometric instruments and the numerous uses of biometrics in humanitarian situations. The approach also entails five expert interviews with individuals involved in refugee issues in Lebanon. The research makes use of the concepts of function creep to explore biometrics data usage and implementation in Lebanon and its implications. The study indicates that the UNHCR biometric operation in Lebanon has attracted new players to improve the efficiency of the UNHCR operation. However, these new actors, such as the UNHCR, WFP, and Iris Guard, take up a position in Lebanon's governance of Syrian refugees. The transfer of responsibility between the GoL and these new actors occurred for political and financial reasons
Setting an Inclusive Framework for Human Security & Social Justice within the IMF and GoL Restructuring and Reform Plan: Education an Equalizer and Enabler : Policy Brief
No full textPublication made possible through the American University of Beirut and Malala Fund Strategic Partnership.This policy brief urges Lebanese policymakers to recognize and address the education crisis in the country, which is being amplified by its current multifaceted economic and social challenges. Prioritizing the protection of the education sector, particularly for vulnerable groups such as women and girls, is critical to prevent its collapse under possible austerity measures associated with International Monetary Fund (IMF) intervention. The brief strongly recommends policy reforms that ensure adequate social safeguards, promote transparency and accountability, and support the restructuring of public finances. The brief underscores the necessity of cooperation between the government, civil society, and international donor community, encouraging increased investment in education infrastructure. Drawing from examples in Tunisia and Jordan, the brief cautions against austerity measures that negatively impact education and widen social and gender disparities. Policymakers are implored to uphold education as an equalizer and enabler, securing its role in fostering long-term sustainable recovery, social peace, and economic development in Lebanon
Effect of Plastic Nets on Saffron Growth
No full textSaffron (Crocus sativus L.) stands as the most expensive spice in the world. Newly introduced to Lebanon, widespread implementations of this crop are blooming in the Beqaa region, especially by AUB Arec through its teachings. Saffron blooms in the fall season, each flower produces three stigmas, and it is estimated that an average of 150 thousand flowers are needed to produce 1 kg of Saffron dry weight. Saffron is a male sterile plant, which duplicates manually through its underground corms. This project was implemented due to the high increase of sunlight in the Beqaa region, which prompted the use of nets as controlled shading to evaluate the optimal environmental growth and development for Saffron. The research will analyze the effect of the number of holes per square Inch in nets.
Each treatment allows a different percentage of light to reach the plants. The experiment portrays a 616 m2 land plot of an already planted saffron field, which held corms 3 years of age, imported from the kingdom of the Netherlands. The research accommodates 5 total treatments, each treatment corresponding to a net covering a plot in different hole number/size, starting from control (no net), followed by two nets with five 0.51cm holes per square Inch, one with twenty-five 0.1cm holes per square Inch, and one with thirty 0.08cm holes per square Inch; control treatment will be left open to the elements to reveal the effect of nets as a comparison to a non-netted plot. These five treatments will be replicated four times.
Our objective is to study which net had the most significance on Saffron growth, development, and increase in the number of blooming flowers, corm number, size, and plant height/cluster number. Higher hole density in nets led to reduced light transmittance, triggering plants to seek light and resulting in increased above-ground biomass.
Nets with lower hole density demonstrated the highest effectiveness by promoting greater flower counts and stigma weights, suggesting a conducive environment for saffron flower growth. Nets with higher hole density positively influenced cormlet formation and proliferation, contributing to the development of cormlets
Sustainability assessment of sanitary pad solutions to reduce period poverty
Get PDFProduction, disposal, and access to menstrual products pose significant challenges in middle- and low-income regions intensifying period poverty. This underscores the urgent need to find sustainable and affordable sanitary product alternatives. This study discusses and compares various types of sanitary pads considering environmental, economic, and social aspects. The labor conditions associated with the production of materials used in sanitary pads and the high cost of disposable plastic-based pads were found to be the main causes of the social and economic strains. A life cycle assessment and environmental cost indicator (ECI) for disposable and reusable pads (virgin cotton, recycled cotton, banana fibers) reveal that disposable pads incur high costs and environmental challenges due to plastic content. Reusable cotton pads can be sustainable, especially if made from recycled cotton, but banana fiber pads are the most environmentally, economically, and socially viable, with an ECI 7 times lower than disposable pads and 3 times lower than reusable cotton pads since 77% of its materials are sourced from agricultural waste. Consequently, it is recommended to encourage the use of bio-based pads like banana fiber pads since their fabrication process is sustainable and simple as materials can be easily sourced. If properly managed, bio-based reusable pads can enable local and women-led production, empowering and providing women with an income source, while ensuring affordable access to sanitary products to combat period poverty. © 2023, The Author(s), under exclusive licence to Springer Nature B.V
GLUT3 promotes macrophage signaling and function via RAS-mediated endocytosis in atopic dermatitis and wound healing
Get PDFThe facilitative GLUT1 and GLUT3 hexose transporters are expressed abundantly in macrophages, but whether they have distinct functions remains unclear. We confirmed that GLUT1 expression increased after M1 polarization stimuli and found that GLUT3 expression increased after M2 stimulation in macrophages. Conditional deletion of Glut3 (LysM-Cre Glut3fl/fl) impaired M2 polarization of bone marrow–derived macrophages. Alternatively activated macrophages from the skin of patients with atopic dermatitis showed increased GLUT3 expression, and a calcipotriol-induced model of atopic dermatitis was rescued in LysM-Cre Glut3fl/fl mice. M2-like macrophages expressed GLUT3 in human wound tissues as assessed by transcriptomics and costaining, and GLUT3 expression was significantly decreased in nonhealing, compared with healing, diabetic foot ulcers. In an excisional wound healing model, LysM-Cre Glut3fl/fl mice showed significantly impaired M2 macrophage polarization and delayed wound healing. GLUT3 promoted IL-4/STAT6 signaling, independently of its glucose transport activity. Unlike plasma membrane–localized GLUT1, GLUT3 was localized primarily to endosomes and was required for the efficient endocytosis of IL-4Rα subunits. GLUT3 interacted directly with GTP-bound RAS in vitro and in vivo through its intracytoplasmic loop domain, and this interaction was required for efficient STAT6 activation and M2 polarization. PAK activation and macropinocytosis were also impaired without GLUT3, suggesting broader roles for GLUT3 in the regulation of endocytosis. Thus, GLUT3 is required for efficient alternative macrophage polarization and function, through a glucose transport–independent, RAS-mediated role in the regulation of endocytosis and IL-4/STAT6 activation. Copyright: © 2023, Yu et al
The Ten Most Common Questions on Cytomegalovirus Infection in Hematopoietic Stem Cell Transplant Patients
No full textWith the rising number of patients undergoing hematopoietic stem cell transplantation (HSCT), clinicians are more likely to encounter infectious complications in immunocompromised hosts, particularly cytomegalovirus (CMV) infection. Besides the high mortality of CMV end-organ disease, patients with detectable CMV viremia may have worse outcomes and decreased survival even in the absence of end-organ disease. In view of the implications on morbidity and mortality, clinicians should maintain a high index of suspicion and initiate antiviral drugs promptly when CMV infection is confirmed. High-risk patients should be identified in order to provide optimal management. Additionally, novel antiviral agents with a good safety profile and minor adverse events are now available for prophylaxis in high-risk patients and for treatment of resistant or refractory CMV infection. The following review provides concise, yet comprehensive, guidance on the burden and risk factors of CMV in this population, as well as an update on the latest evidence for the management of CMV infection. © 2022, The Author(s)
Broadband ferromagnetic resonance of ultrathin yttrium iron garnet films by pulsed laser deposition: Effects of deposition parameters
Get PDFIn this study, we investigate the growth and characteristics of ultrathin ferrimagnetic yttrium iron garnet (YIG, Y3Fe5O12) films on a Gallium Gadolinium Garnet (GGG) substrate using the pulsed laser deposition technique (PLD). We aim to improve the magnetic quality of the films by varying the deposition parameters, specifically the laser energy and oxygen pressure. We conduct broadband ferromagnetic resonance (FMR) measurements to characterize the magnetic properties and Gilbert damping of the films. Our findings demonstrate that adjusting the deposition parameters systematically controls the saturation magnetization and Gilbert damping of YIG films. Our measurements show that in the absence of oxygen, the films exhibit higher-than-expected values of magnetization and Gilbert damping, suggesting that the films have a higher Fe concentration. Conversely, when introducing oxygen in the chamber, we observe a decrease in the magnetization and damping values, approaching those of bulk YIG films. Notably, we achieve a saturation magnetization of 0.185 T and an ultra-low Gilbert damping of 1.7 × 10−4 for films deposited under conditions of high laser energy and oxygen pressure. This is mainly due to a better Y:Fe ratio approaching the stoichiometric value of 0.6 as the oxygen pressure increased. Our findings provide valuable insights for preparing high-quality ferrimagnetic films suitable for various magnonics applications and spin Hall devices. © 2023 Elsevier B.V
