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The process of pulping and papermaking is a complicated, resource-demanding operation that requires energy, water, and chemicals. When not managed properly, the process can also contribute significantly to pollution. The washing process is one critical operation that impacts the process's economics and environmental footprint. Most mills utilize rotary vacuum washers to separate black liquor from pulp, ensuring clean pulp for further processing downstream. Numerous factors influence the efficiency of a brown stock washer, and the washing operation itself is intricate. This study employs the system dynamics modeling approach to examine the critical role of brown stock washing in the pulp and paper industry, emphasizing optimizing process parameters for improved efficiency and sustainability. In the first part of the paper, a single stage of the washer system is modeled by establishing mass balance equations for key streams, including pulp, liquor, and dissolved solids. Within the system dynamics environment, separate models are developed for each stream, allowing for a detailed analysis of their behavior. To enhance modeling efficiency, the brown stock washing process is divided into four distinct operations: dilution, pulp formation, washing, and filtration. Breaking down the process into these operations makes it possible to focus on optimizing each step for improved overall performance. Furthermore, a control strategy is implemented to ensure stability in critical areas such as dilution vat level, discharged pulp consistency, and filtration tank level. In the final phase of the research, a multistage countercurrent brown stock washing line comprising three washers is modeled. Researchers can gain insights into how different components interact and influence overall performance by evaluating various parameters and analyzing the line's efficiency. This comprehensive analysis enables them to identify potential improvements and optimize the washing process for enhanced productivity and quality output. The conclusions drawn from this work offer valuable guidance for optimizing water management practices in the pulp and paper sector, contributing to the industry's sustainability goals and regulatory compliance. [ABSTRACT FROM AUTHOR] more...

Sustainability and energy efficiency are now two pivotal goals that society aims towards. Green roofs and facades have gained significant attention in this direction for innovative, sustainable solutions for enhancing building energy performance. With a focus on sustainable urban development and energy-efficient building practices, this study delves into the intricate relationship between these green infrastructure elements and the overall energy dynamics of constructed environments. Furthermore, a range of case studies from diverse geographical locations are presented to provide valuable insights into their practical implications as emerging technologies that contribute to improved insulation, reduced heat transfer, regulating indoor temperatures, and mitigation of urban heat island effects, thus reducing the need for artificial heating and cooling and optimizing overall energy consumption. This comprehensive review serves as a dataset for understanding and highlighting all the research findings of the numerical and experimental investigations invested in the field of greenery systems to encourage their integration, which is crucial for combating climate change and pollution. Previous research is often focused on isolated, short-term, or single-climate analyses of consumption; therefore, by providing an inclusive description of their practical benefits in both temperate and extreme climates, the gap in previous articles is tackled. [ABSTRACT FROM AUTHOR] more...

This paper aims to determine the environmental benefits associated with the implementation of a solar PV system to complement the conventional Electricité Du Liban/genset electrical system for the delivery of energy to an industrial facility. The selected case study is a juice manufacturing industrial facility located in Lebanon. Its energy demand is 6000 MWh/year. The components of the PV/hybrid energy system are the following: one 420 modules PV generator, seven three-phase grid-dependent inverters, three 1000 kW generators and one 500 kW generator. The ecoinvent database is used to model the life cycle inventory, and the IMPACT 2002+ methodology is used for the life cycle impact assessment. Results show at the assembly level that the manufacturing of the photovoltaic modules, mounting system components, inverters and cables results in harmful emissions that increase the system's environmental impacts. However, a comparative analysis between the entire life cycle of the PV/hybrid system and the conventional system indicates that the incorporation of the photovoltaic system results in a reduction in environmental impacts across all categories. The end-of-life scenario comprises landfilling/incineration and recycling of the components. Results show that the end-of-life stage poses a minor contribution to the overall life cycle impacts. [ABSTRACT FROM AUTHOR] more...

Infections are well‐known complications in patients following traumatic injuries, frequently leading to high morbidity and mortality. In particular, trauma occurring in disaster settings, both natural and man‐made, such as armed conflicts and explosives detonation, results in challenging medical conditions that impede the best management practices. The incidence of invasive fungal infections (IFI) is increasing in trauma patients who lack the typical risk factors like an immune compromised state or others. This narrative review will focus on IFI as a direct complication after natural disasters, wars, and man‐made mass destruction with a summary of the available evidence about the epidemiology, clinical manifestations, risk factors, microbiology, and proper management. In this setting, the clinical manifestations of IFI may include skin and soft tissue infections, osteomyelitis, visceral infections, and pneumonia. IFI should be considered in the war inflicted patients who are exposed to unsterile environments or have wounds contaminated with soil and decaying organic matter. [ABSTRACT FROM AUTHOR] more...

Background: Infectious agents associated with community-acquired acute respiratory infections (ARIs) remain understudied in Lebanon. We aim to assess the microbiological profiles of ARIs by employing polymerase chain reaction (PCR) and identifying predictors of positive PCR results among patients admitted for ARI. Methods and results: We conducted a retrospective single-center study at the American University of Beirut Medical Center, including all respiratory PCR panels performed on pediatric (< 18) and adult (≥ 18) patients presenting with an ARI from January 2015 to March 2018, prior to the onset of the COVID-19 pandemic. We aimed to identify the epidemiological patterns of ARIs and the factors associated with positive PCRs in both adult and pediatric patients. Among 281 respiratory PCRs, 168 (59.7%) were positive for at least one pathogen, with 54.1% positive PCR for viruses, 7.8% for bacteria species, and 3.9% with virus-bacteria codetection. Almost 60% of the patients received antibiotics prior to PCR testing. PCR panels yielded more positive results in pediatric patients than in adults (P = 0.005). Bacterial detection was more common in adults compared to pediatrics (P < 0.001). The most common organism recovered in the entire population was Human Rhinovirus (RhV) (18.5%). Patients with pleural effusion on chest CT were less likely to have a positive PCR (95% Cl: 0.22–0.99). On multivariate analysis, pediatric age group (P < 0.001), stem cell transplant (P = 0.006), fever (P = 0.03) and UTRI symptoms (P = 0.004) were all predictive of a positive viral PCR. Conclusion: Understanding the local epidemiology of ARI is crucial for proper antimicrobial stewardship. The identification of factors associated with positive respiratory PCR enhances our understanding of clinical characteristics and potential predictors of viral detection in our population. [ABSTRACT FROM AUTHOR] more...

Background: Infectious agents associated with community-acquired acute respiratory infections (ARIs) remain understudied in Lebanon. We aim to assess the microbiological profiles of ARIs by employing polymerase chain reaction (PCR) and identifying predictors of positive PCR results among patients admitted for ARI. Methods and results: We conducted a retrospective single-center study at the American University of Beirut Medical Center, including all respiratory PCR panels performed on pediatric (< 18) and adult (≥ 18) patients presenting with an ARI from January 2015 to March 2018, prior to the onset of the COVID-19 pandemic. We aimed to identify the epidemiological patterns of ARIs and the factors associated with positive PCRs in both adult and pediatric patients. Among 281 respiratory PCRs, 168 (59.7%) were positive for at least one pathogen, with 54.1% positive PCR for viruses, 7.8% for bacteria species, and 3.9% with virus-bacteria codetection. Almost 60% of the patients received antibiotics prior to PCR testing. PCR panels yielded more positive results in pediatric patients than in adults (P = 0.005). Bacterial detection was more common in adults compared to pediatrics (P < 0.001). The most common organism recovered in the entire population was Human Rhinovirus (RhV) (18.5%). Patients with pleural effusion on chest CT were less likely to have a positive PCR (95% Cl: 0.22–0.99). On multivariate analysis, pediatric age group (P < 0.001), stem cell transplant (P = 0.006), fever (P = 0.03) and UTRI symptoms (P = 0.004) were all predictive of a positive viral PCR. Conclusion: Understanding the local epidemiology of ARI is crucial for proper antimicrobial stewardship. The identification of factors associated with positive respiratory PCR enhances our understanding of clinical characteristics and potential predictors of viral detection in our population. [ABSTRACT FROM AUTHOR] more...

The building sector, one of the most energy-consuming, is among the most current topics due to the maturing concerns about the anthropogenic factor's impact on CO2 quantities in the atmosphere and its association with global temperature rise. Using sustainable building materials is a promising alternative in building envelope applications to improve in-use energy efficiency. These materials, having a low environmental impact, the advantage of being renewable, and low embodied energy, contribute to global sustainability. This comprehensive literature review presents a broad overview of these materials' hygrothermal characteristics, thermal performance, and energy use. The main goal is to compile the most important research findings on these materials' capabilities for building construction and their contributions and effects on energy performance and thermal insulation. [ABSTRACT FROM AUTHOR] more...

Invasive fungal infections, notably candidemia, have been associated with COVID-19. The epidemiology of candidemia has significantly changed during the COVID-19 pandemic. We aim to identify the microbiological profile, resistance rates, and outcomes of COVID-19-associated candidemia (CAC) compared to patients with candidemia not associated with COVID-19. We retrospectively collected data on patients with candidemia admitted to the American University of Beirut Medical Center between 2004 and 2022. We compared the epidemiology of candidemia during and prior to the COVID-19 pandemic. Additionally, we compared the outcomes of critically ill patients with CAC to those with candidemia without COVID-19 from March 2020 till March 2022. Among 245 candidemia episodes, 156 occurred prior to the pandemic and 89 during the pandemic. Of the latter, 39 (43.8%) were CAC, most of which (82%) were reported from intensive care units (ICU). Non-albicans Candida (NAC) spp. were predominant throughout the study period (67.7%). Candida auris infection was the most common cause of NAC spp. in CAC. C. glabrata had decreased susceptibility rates to fluconazole and caspofungin during the pandemic period (46.1% and 38.4%, respectively). The mortality rate in the overall ICU population during the pandemic was 76.6%, much higher than the previously reported candidemia mortality rate observed in studies involving ICU patients. There was no significant difference in 30-day mortality between CAC and non-CAC (75.0% vs. 78.1%; p = 0.76). Performing ophthalmic examination (p = 0.002), CVC removal during the 48 h following the candidemia (p = 0.008) and speciation (p = 0.028) were significantly associated with a lower case-fatality rate. The epidemiology of candidemia has been significantly affected by the COVID-19 pandemic at our center. Rigorous infection control measures and proper antifungal stewardship are essential to combat highly resistant species such as C. auris. [ABSTRACT FROM AUTHOR] more...

Cake washing has been used to remove compounds trapped in the pores of a filter cake. These compounds could be desired products that should be recovered. Cake washing and electrowashing have been studied and found to present many benefits, but in some cases washing filter cakes can be a slow process. In this work, electrowashing (EW) and pressure electrowashing (PEW) were for the first time applied to enhance the liquid flowing in the the algal filter cake, which has a very high specific resistance and low washing velocity. The new EW and PEW processes were compared with conventional pressure washing (PW) of Arthrospira platensis microalgae. Washing was carried out to extract desired biocompounds (CPC, APC and proteins) from the filter cake. The study showed that the use of a constant direct current (60 A/m2) coupled with the effect of an applied hydraulic pressure was an effective way to increase the cake washing kinetics. It also demonstrated that it was possible to extract proteins and pigments by applying the washing by displacement technique. [ABSTRACT FROM AUTHOR] more...

Harvesting microalgae has presented many challenges in the past, especially when taking into account the final dryness of the product and the energy requirements for the drying process. This study investigates the use of dead-end electrofiltration to dewater an Arthrospira platensis suspension under different pressures (1 to 4 bar) and electric current densities (30 to 80 A/m2). Filtration without an electric field helped reach a final cake dryness in the range of 13.3-15%. Electrofiltration was found to be a more effective dewatering method, reaching a final cake dryness of up to 20.8% with an energy consumption of 0.105 kWh/kg water removed, which is significantly lower than the energy consumption reported in literature. Increasing the electric current density helped increase the cake dryness, whereas increasing the operating pressure was not effective enough due to the high cake compressibility. Electrofiltration also modifies the filtrate and cake properties due to the electrolysis reactions. [ABSTRACT FROM AUTHOR] more...

Arthrospira platensis (A. platensis) is a microalga with a wide range of commercial uses. One of the main concerns that needs to be addressed in microalgae biorefineries is the costs associated with the harvesting and concentration steps. Filtration has been shown to be an effective technique for concentrating microalgae and recent studies have attempted to enhance membrane filtration by applying an external electric field to the filtration cell. This study consisted of assessing the use of electrically assisted filtration (electrofiltration) at 60 A/m2 and 1 bar for the dewatering of A. platensis, as well as the effect of pretreating the microalgae with ultrasounds (US) on the filtration process. Untreated A. platensis exhibited better filtration kinetics than US-treated A. platensis, and electrofiltration was found to increase the cake dryness. More protein and pigments were present in the US-treated microalgae solution compared to the untreated microalgae, which led to the presence of higher concentrations of protein and pigments in the filtrate streams after pressure filtration at 1 bar without the application of an external electric field. Electrofiltration was found to consume less energy compared to traditional drying techniques used for A. platensis. However, electrofiltration degrades the biocompounds present in the filtrate and cake due to pH changes and other electrophoresis phenomena, which shows the need to optimize the process in future work. [ABSTRACT FROM AUTHOR] more...

In an effort to standardize practice, the European Confederation of Medical Mycology (ECMM) developed the European Confederation of Medical Mycology Quality of Clinical Candidaemia Management (EQUAL) Candida score. This study investigated the utility of the EQUAL Candida score in predicting mortality in patients with candidemia admitted between January 2004 and July 2019. A total of 142 cases were included in the study, and 43.6% died within 30 days of candidemia diagnosis. There were no significant differences between survivors and non-survivors in terms of comorbidities predisposing to candidemia, except for malignancy (p = 0.021). The overall mean EQUAL score was 11.5 in the total population and 11.8 ± 3.82 and 11.03 ± 4.59 in survivors and non-survivors, respectively. When patients with a central venous catheter (CVC) were considered alone, survivors were found to have significantly higher scores than non-survivors (13.1 ± 3.19 vs. 11.3 ± 4.77, p = 0.025). When assessing components of the EQUAL Score separately, only candida speciation (p = 0.013), susceptibility testing (p = 0.012) and echocardiography results (p = 0.012) were significantly associated with a lower case-fatality rate. A higher EQUAL Candida score was able to predict a lower case-fatality rate in patients with a CVC. [ABSTRACT FROM AUTHOR] more...

Palliative care is increasingly recognized as fundamental to health and human dignity. However, a growing body of evidence highlights the variations in access to palliative care based on personal characteristics, belonging to a certain group, and socioeconomic background. Discriminatory attitudes and behaviors and lack of legal reform protecting the rights of marginalized populations are still common, particularly across Lebanon and the Middle East and North Africa region. This article presents a summary of a roundtable discussion organized by the Lebanese Medical Association for Sexual Health in collaboration with the Lebanese Center for Palliative Care-Balsam, focusing on improving palliative care provision for the following populations: prisoners; lesbian, gay, bisexual, and transgender people; refugees; migrant domestic workers; and people with substance use disorder. It also offers recommendations based on the key themes identified from the discussion, in the hope that they will guide the development of guidelines and policy to advance equity in palliative care provision for marginalized populations. [ABSTRACT FROM AUTHOR] more...

Infections are the most commonly encountered complications in patients with cancer. The classical signs and symptoms of infections are often not present in this patient population, which makes the diagnosis more challenging. Host factors play a major role in the development and prognosis of infections in cancer patients; these can be related to the underlying type of malignancy (solid organ versus hematological), tumor burden, anatomic obstruction, altered integrity of barriers (skin or mucosa), treatment-related factors (from chemotherapy, radiation treatment, surgery, interventional procedures, and/or medical device placement) and the degree of immunosuppression. This article reviews common, as well as less common, imaging manifestations of infections and their potential mimics in the abdomen and pelvis in cancer patients and discusses their differentiating features, with the role of imaging in various organs in the abdomen and pelvis taking into consideration relevant clinical background information and the main risk factors. [ABSTRACT FROM AUTHOR] more...

Background: Telemedicine has been proposed as a means to improve access to palliative care. There is limited information about how health care workers feel about providing this kind of care and how families feel about receiving it. Objective: This study assesses provider and caregiver perceptions of the safety and efficacy of the Distance Support Program (DSP) of a home-based palliative care provider in Beirut, Lebanon. Design: Interviews were conducted with 8 physicians and nurses who provided that care through the DSP as well as 49 caregivers of patients who received care between January 2015 and December 2017. Interviews were analyzed thematically. Results: Although they would have preferred having access to home visits, caregivers reported that they valued the information, guidance, and emotional support they received through the DSP and they appreciated having telephone access to providers. Health providers reported the DSP was more efficient than home visits. They felt it was safest when delivered by an experienced provider, they had access to a reliable caregiver, and the patient was assessed at least once. They felt it was important to communicate clear expectations to patients and caregivers when delivering care by telephone. Conclusions: Telemedicine can be a useful tool to provide palliative care services in settings where they would otherwise not be available. [ABSTRACT FROM AUTHOR] more...

Hand, foot, and mouth disease (HFMD) is an acute and highly contagious viral illness mainly affecting the pediatric population. Recently, there has been an increasing number of reported adult-onset HFMD.[[1], [3], [5], [7]] It is estimated that around 11% of exposed adults get infected and less than 1% manifest the disease,[5] possibly relating to childhood enterovirus exposure leading to cross-immunity and immunologic memory.[8] Compared to childhood-onset disease, adult-onset HFMD may have an altered disease course and clinical manifestations. [Extracted from the article] more...

Objectives Invasive aspergillosis (IA) caused by Aspergillus terreus is a significant cause of morbidity and mortality in patients with haematological malignancy (HM). Very few data are available in this patient population to differentiate IA patients with A. terreus from those with non-terreus species of Aspergillus to compare outcomes. We retrospectively investigated 513 HM patients who were treated for either definite or probable IA between June 1993 and August 2012 in a cancer centre. Methods We compared baseline characteristics, antifungal therapies and outcomes between patients infected with A. terreus (n = 96, 18.7%) and those infected with non-terreus Aspergillus species (n = 335, 65.3%). Eighty-one patients with mixed or unspecified Aspergillus infections were excluded. Results Breakthrough infections occurred more frequently in the A. terreus group (91% versus 77%, P = 0.009). A. terreus infection was associated with a lower rate of final response to antifungal therapy (21% versus 38%, P = 0.0015) and a higher rate of IA-associated mortality (51% versus 30%, P < 0.001). Multivariate analyses showed that these associations were independent of patients' clinical characteristics and the antifungal regimens they received. Factors independently associated with final response included treatment with azoles (OR 3.1, 95% CI 1.9–5.0, P < 0.0001) and Aspergillus species (A. terreus versus non-terreus Aspergillus species) (OR 0.5, 95% CI 0.3–0.98, P = 0.043). Additionally, Aspergillus species and treatment with azoles were independently associated with IA-associated mortality. Conclusions A. terreus IA in HM patients was associated with worse outcome than IA caused by non-terreus Aspergillus species. Poor prognosis in patients with invasive A. terreus infections is independent of anti-Aspergillus azole-based treatment. [ABSTRACT FROM PUBLISHER] more...

Background. There are limited data regarding clinical presentation and management of Staphylococcus aureus central line- associated bloodstream infection (CLABSI) in immunocompromised cancer patients. Methods. In this review, we evaluated 299 patients with 304 episodes of S. aureus -CLABSI between 2005 and 2011. Findings. By multivariate analysis, the major predictors of complicated S. aureus-CLABSI were septic shock, catheter site inflammation, presence of peripherally inserted central catheter, anti-cancer chemotherapy within 10 days, and persistent bacteremia beyond 72 hours ( P ≤ 0.02). A total of 67% of the cases were defined as complicated. In the subset of patients who were uncomplicated on presentation, patients receiving antimicrobials ≥ 14 days had similar rates of relapse, attributable mortality, and development of complications compared to those receiving shorter-course therapy. By competing risk analysis, removal of the catheter within 3 days of the onset of bacteremia was associated with a lower relapse rate at 90 days ( P = 0.024). Interpretation. The majority of S. aureus-CLABSI in cancer patients are complicated and require prolonged course of antimicrobial treatment. Early removal of the catheter within the first 3 days is associated with better course. In patients with prompt removal of the catheter and no evidence of a complicated course, treatment beyond 2 weeks may not be necessary. [ABSTRACT FROM AUTHOR] more...

Background: Central venous catheters (CVC) removal and reinsertion of a new CVC in the setting of central line associated bloodstream infections (CLABSI) is not always possible in septic patients. The purpose of this study was to evaluate the outcome of patients with Staphylococcus aureus-CLABSI (SA-CLABSI) who had their CVCs exchanged over guidewire for minocycline/rifampin-coated (M/R)-CVC within seven days of bacteremia. Methods: Each case was matched with two control patients who had SA-CLABSI and had their CVC removed within seven days and two control patients who had their CVC retained beyond seven days. In addition, an in vitro model was developed for exchange of catheters. Results: We identified 40 patients with SA-CLABSI. Eight patients had their CVC exchanged over guidewire with M/R-CVC and were compared to 16 patients who had their CVC removed and 16 other patients who had their CVC retained. Patients who had their CVC exchanged over guidewire had a similar clinical response and relapse rates compared to patients whose CVC was removed or retained. However the rate of overall mortality was higher in patients who retained their CVC compared to those whose CVC was exchanged or removed (p = 0.034). The in vitro catheter exchange model showed that catheter exchange over guidewire using M/R-CVC completely prevented biofilm colonization compared to exchange using uncoated CVC (p < 0.0001). Conclusions: In the setting of SA-CLABSI, exchanging the CVC over guidewire with M/R-CVC could be an alternative to removing the CVC and reinserting another CVC at a different site and may be associated with a lower rate of overall mortality. Further large prospective randomized clinical trials are warranted. [ABSTRACT FROM AUTHOR] more...

Rapidly growing mycobacteria (RGM) are environmental organisms capable of causing a wide spectrum of diseases. We identified 116 cancer patients with RGM. Mycobacterium mucogenicum was the leading cause of disease. Removal of the catheter correlated with significant decrease in the bacteremia relapse rate (P = .007). A median duration of 4 weeks of therapy produced a good outcome. [ABSTRACT FROM PUBLISHER] more...

The present study aims to determine the carcinogenic and neurotoxic risks associated with acrylamide intake from cereal products. Analysis on a UPLC–MS/MS spectrometer revealed that oat-based and mixed cereals contain the highest amount of acrylamide among cereal products with levels as high as 271 and 348 μg/kg, respectively. Children were shown to exhibit both carcinogenic and neurotoxic risks regardless of the type of cereal product consumed. For adults above 50 years of age, only consumers of oat-based cereal products seem to exhibit carcinogenic and neurotoxic risks. To avoid a carcinogenic and neurotoxic risk among the Lebanese population, we propose that food processors set the maximum tolerable concentration for acrylamide in cereal products at 94.8 μg/kg product, a value which is threefolds lower than the average acrylamide levels found in this study. Alternatively, and unreasonably, the average Lebanese population and children among the Lebanese population may choose to cut down on cereal consumption by 1.7- and 7.2-folds respectively, should they want to avoid a health hazard as a result of acrylamide intake. The industry should also respond by optimizing the production process in a way to reduce acrylamide levels in cereals. [ABSTRACT FROM AUTHOR] more...

Asbestos-cement was manufactured and used in Lebanon since the early 1950s. Corrugated rooftops of asbestos-cement were mostly spread within residential areas throughout the country. These rooftops are subject to weathering factors which are known to increase friability and risk of hazardous fiber release. This study aimed at assessing the asbestos-cement rooftop friability and the possible emerging risks in the urban-industrial city of Chekka, North Lebanon. The evaluation of the asbestos-cement included two field assessment algorithms and a standardized pull-up test. Hazard of fiber emissions was assessed by a pull-up test method, whereas vulnerability was determined by a level of interaction between people and the rooftops. Geographic object-based image analysis was used to map hazard, vulnerability, and risk of asbestos rooftops in the study area. The field algorithms classified most rooftops in a bad state compared with the pull-up test which ranked most of them as good. The X-ray diffraction analysis showed the presence of serpentine and amphibole fibers, except for crocidolite, in some rooftop samples. Hazard, vulnerability, and risk maps of the sampled area showed how hazard potential was amplified by vulnerability of population to possible fiber emission. [ABSTRACT FROM AUTHOR] more...