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Yiwen Fan1, Alexander C Pauer1, Arthur A Gonzales1, Hicham Fenniri1–3 1Department of Chemical Engineering, Northeastern University, Boston, MA 02115, USA; 2Department of Bioengineering, Northeastern University, Boston, MA 02115, USA; 3Department of Chemistry and Chemical Biology, Northeastern University, Boston, MA 02115, USACorrespondence: Hicham FenniriDepartment of Chemical Engineering, Northeastern University, 360 Huntington Avenue, Boston, MA 02115, USATel +1 617 373 7690Fax +1 617 373 2209Email h.fenniri@northeastern.eduPurpose: This work presents the preparation of a nanocomposite of ampicillin-conjugated gold nanoparticles (AuNPs) and self-assembled rosette nanotubes (RNTs), and evaluates its antibacterial properties against two strains of drug-resistant bacteria (Staphylococcus aureus [S. aureus], methicillin-resistant S. aureus [MRSA]).Materials and methods: Small, nearly monodisperse AuNPs (1.43±0.5 nm in diameter) nucleated on the surface of polyethylene glycol-functionalized RNTs in a one-pot reaction. Upon conjugation with ampicillin, their diameter increased to 1.86±0.32 nm. The antibacterial activity of the nanocomposite against S. aureus and MRSA was tested using different concentrations of ampicillin. The cytocompatibility of the nanocomposite was also tested against human dermal fibroblasts.Results: Based on bacterial inhibition studies, the nanocomposite demonstrated enhanced antibiotic activity against both bacterial strains. The minimum inhibitory concentration (MIC) of the nanocomposite against S. aureus was found to be 0.58 μg/mL, which was 18% lower than ampicillin alone. The nanocomposite also exhibited a 20 hrs MIC of 4 μg/mL against MRSA, approximately 10–20 times lower than previously reported values for ampicillin alone. In addition, at concentrations of 4 μg/mL of ampicillin (70 μg/mL of AuNPs), the nanocomposite showed negligible cytotoxic effects.Conclusion: Our findings offer a new approach for the treatment of drug-resistant bacteria by potentiating inhibitory effects of existing antibiotics, and delivering them using a non-toxic formulation.Keywords: ampicillin, rosette nanotubes, gold nanoparticles, S. aureus, methicillin-resistant S. aureus

Pseudomonas aeruginosa is a common pathogen of acute and chronic infections that can increase risk to burned patients and those with chronic wounds, especially when forming biofilms. These complex ecosystems are formed by several bacteria that communicate, cooperate, and compete with each other. To enhance its survival capacity in such a competitive environment, P. aeruginosa produces secondary metabolites with a range of biological activities, among other factors. Here, we evaluated how such bioactive molecules mediate intraspecies interactions to modulate P. aeruginosa biofilm formation. An overall decrease in biofilm formation on the surface of stainless steel coupons was observed for both dual-strain and single-strain biofilms formed in the presence of secondary metabolites extracted from other P. aeruginosa strains. Modulation of biofilm formation by these metabolites during P. aeruginosa intraspecies interactions suggests a role for these molecules in strain competition. The most likely mechanism by which it occurs might be modulation of iron uptake. Among the genes analyzed, those related to import (tonB1) and biosynthesis (pvdS) of the siderophore pyoverdine were the most downregulated during exposure to the metabolite extracts. Exploring P. aeruginosa intraspecies interactions during biofilm formation might be an interesting approach to understand its lifestyle better and, thus, the mechanisms involved in the species’ biofilm formation.

Abstract One of the serious challenges for the implementation of continuous emulsion polymerisation is their significant fouling. The elucidation of time-dependent fouling processes and the development of inline analysis methods for fouling mass quantification are crucial to making progress in this area. Inline-sensor concepts based on ultrasonic measurements as well as residence time and conversion analysis were investigated regarding their suitability for the detection of time-dependent fouling formation and compared with gravimetrical results in order to validate their precision. Both a set-up using a turnover analysis for determination of losses in reaction volume by fouling and an ultrasound-based measurement system detecting deposit-caused changes by evaluating the average sound velocity could be used as suitable sensor concepts. The accuracies of both sensors are below 10% deviation to fouling references.

This paper discusses the possibility of deploying automated guided vehicle (AGV) technology in a company’s production hall. Chronometric measurements of material handling and people handling were performed. The handling processes were divided into five sub-processes, which were analysed in terms of production line operation, distance, and carrying capacity of the automated guided vehicles. Based on the measurements, we found that it was necessary to use four vehicles for handling in the foam production hall. The company is applying this automation project to foams, and after successful testing, plans to continue with automation for leather upholstery. To ensure the correct chronometric results, we measured the distances between each workstation on the production floor at the company. Based on an analysis of material handling on the production lines, we evaluated that there is a possibility of applying AGVs on the entire production floor. We analysed the volumes of material transfer and the possibilities of interconnection within the existing material handling in the enterprise. Complications arise when deploying AGVs in the plant because the handling to the production lines is not only provided by the parent company, but also by the component suppliers themselves. Based on this observation, we have identified potential collision points within the operation between automated guided vehicles and other material handling equipment or people. For this reason, we deployed one more AGV on the handling routes to prevent unwanted collisions. This means that a human would be able to perform even more processes than a machine and can circulate 80 times, where a machine under the same conditions would only perform the entire circulation 57 times. There is room here to use humans for other processes and to automate the handling of goods, although it introduces delays that can be eliminated by deploying additional automated guided vehicles. This opens room for further research questions on how these vehicles can be deployed, even in a small space, and how existing material handling can be automated.

BackgroundIntestinal organoids are stem cell-derived, 3D “mini-guts” with similar functions as the native intestinal epithelium such as electrolyte transport or establishment of an epithelial barrier. During intestinal inflammation, epithelial functions are dysregulated by proinflammatory cytokines like tumor necrosis factor α (TNFα) and other messengers from the immune system resulting in a loss of electrolytes and water due to an impaired epithelial barrier and higher net secretion.MethodsA murine small intestinal organoid model was established to study (long-term) effects of TNFα on the intestinal epithelium in vitro using live imaging, immunohistochemical staining and qPCR.ResultsTNFα induced apoptosis in intestinal organoids as indicated by an increased number of cells with immunoreactivity for cleaved caspase 3. Furthermore, TNFα exposure led to swelling of the organoids which was inhibited by bumetanide and was concomitant with an upregulation of the bumetanide-sensitive Na+-K+-2Cl- symporter 1 (NKCC1) as shown by qPCR. Fura-2 imaging experiments revealed time-dependent changes in Ca2+ signaling consisting of a rise in the basal cytosolic Ca2+ concentration at day 1 and an increase of the carbachol-induced Ca2+ response after 3 days TNFα exposure. This was prevented by preincubation with La3+, an inhibitor of non-selective cation channels, or by using a Ca2+-free buffer indicating an enhancement of the Ca2+ influx from the extracellular side by the cytokine. No significant changes in cDNA levels of epithelial barrier proteins could be observed in the presence of TNFα.ConclusionIntestinal organoids are a useful tool to study the mechanism underlying the TNFα-induced secretion on enterocytes such as the regulation of NKCC1 expression or the modulation of cellular Ca2+ signaling.

AbstractBackground Early in the COVID-19 pandemic, GPs had to distinguish SARS-CoV-2 from other aetiologies in patients presenting with respiratory tract infection (RTI) symptoms on clinical grounds and adapt management accordingly.Objectives To test the diagnostic accuracy of GPs’ clinical diagnosis of a SARS-CoV-2 infection in a period when COVID-19 was a new disease. To describe GPs’ management of patients presenting with RTI for whom no confirmed diagnosis was available. To investigate associations between patient and clinical features with a SARS-CoV-2 infection.Methods In April 2020–March 2021, 876 patients (9 countries) were recruited when they contacted their GP with symptoms of an RTI of unknown aetiology. A swab was taken at baseline for later analysis. Aetiology (PCR), diagnostic accuracy of GPs’ clinical SARS-CoV-2 diagnosis, and patient management were explored. Factors related to SARS-CoV-2 infection were determined by logistic regression modelling.Results GPs suspected SARS-CoV-2 in 53% of patients whereas 27% of patients tested positive for SARS-CoV-2. True-positive patients (23%) were more intensively managed for follow-up, antiviral prescribing and advice than true-negatives (42%). False negatives (5%) were under-advised, particularly for social distancing and isolation. Older age (OR: 1.02 (1.01–1.03)), male sex (OR: 1.68 (1.16–2.41)), loss of taste/smell (OR: 5.8 (3.7–9)), fever (OR: 1.9 (1.3–2.8)), muscle aches (OR: 2.1 (1.5–3)), and a known risk factor for COVID-19 (travel, health care worker, contact with proven case; OR: 2.7 (1.8–4)) were predictive of SARS-CoV-2 infection. Absence of loss of taste/smell, fever, muscle aches and a known risk factor for COVID-19 correctly excluded SARS-CoV-2 in 92.3% of patients, whereas presence of 3, or 4 of these variables correctly classified SARS-CoV-2 in 57.7% and 87.1%.Conclusion Correct clinical diagnosis of SARS-CoV-2 infection, without POC-testing available, appeared to be complicated.

Stargardt macular degeneration (STGD) is a central blinding disease caused by loss of or dysfunctional ABCA4 transporter in both photoreceptors and retinal pigment epithelial (RPE) cells. Toxic bisretinoid-lipofuscin buildup in the RPE cells is a pathological hallmark of STGD patients and its mouse model, the Abca4-/-. These vitamin A-derived fluorophores have been shown to induce oxidative stress, stimulate complement activity, and cause chronic inflammation of the RPE. In vivo modulation of complement regulatory pathway in the STGD mouse model has partially rescued the STGD phenotype suggesting that complement attack on the RPE is an important etiologic factor in disease pathogenesis. While bisretinoid-dependent complement activation was further evidenced in cultured RPE cells, this pathway has never been investigated directly in the context of RPE from STGD donor eyes. In the current study, we evaluate the complement reactivity in postmortem donor eyes of clinically diagnosed STGD patients. All three STGD donor eyes RPE displayed strong immunoreactivity for an antibody specific to 4-Hydroxynonenal, a lipid peroxidation byproduct. Also, unlike the control eyes, all three STGD donor eyes showed significantly increased membrane attack complex deposition on the RPE cells. In STGD eyes, increased MAC accumulation was mirrored by elevated C3 fragments internalized by the RPE and inversely correlated with the levels of complement factor H, a major complement regulatory protein. Here, we report the first direct evidence of RPE complement dysregulation as a causative factor in developing Stargardt phenotype.

PurposeTo describe the pathology of AMD in eyes with geographic atrophy (GA) using confocal scanning laser ophthalmoscopy (SLO) blue light autofluorescence (BAF), and near-infrared (IR) AF and to correlate it with the histology and immunohistochemistry analysis at the margins of the GA lesion.MethodsEnucleated, fixed eyes from seventeen donors with GA were imaged and analyzed by BAF-SLO, IRAF-SLO, and by fundus macroscopy (FM). Tissue from the margins of the GA lesions was cut and processed for resin embedding and histology or cryosectioning and fluorescence in the green and far-red channels, and immunohistochemistry to assess markers of inflammation. Isolated DNA from donors was genotyped for single nucleotide polymorphisms (SNPs) previously shown to be risk factors for the development and progression of AMD.ResultsAround the leading edge of the GA lesions we observed hypertrophic RPE cells with cytoplasm filled with granules fluorescent both in the far-red and green-red channels; abundant microglia and macrophage; deposition of complement factor H (CFH) in Bruch's membrane (BM) and increased membrane attack complex (MAC) on RPE cells.ConclusionsFluorescence imaging of cryosections of RPE cells around the leading edge of the GA lesions suggest that IRAF-SLO visualizes mostly melanin-related compounds. In addition, medium-size GA atrophy displayed the most significant changes in inflammation markers.

Cover cropping provides versatile benefits for sustainable agriculture, but many cover crops are potential host plants for pathogens such as Sclerotinia sclerotiorum (Lib.) de Bary. Therefore, 14 cover crops were investigated for their interaction with sclerotia, topsoil moisture and temperature in two consecutive field trials in East Austria. In July, after the cover crops were sown, sclerotia were inoculated at 3 cm soil depth in two mesh tubes per plot with 1×1 mm and 3×10 mm mesh size and remained until March. Cover crops did not affect decay of sclerotia, but sclerotia declined faster in 3×10 mm mesh compared to 1×1 mm (75.7 and 54.7%; respectively). Degree days reached the required 500 °C for apothecia development in September in both years, but only in year 1 was topsoil moisture sufficient for apothecia development. Nonmetric dimensional scaling revealed that, among others, topsoil temperature in March was significant for sclerotia germination in spring and was independent of plant biomass. There are indications that Poaceae such as sorghum × Sudan grass and Sudan grass can stimulate early germination under cover crops, causing vulnerability of sclerotia to degradation. This could reduce the pathogen pressure for the subsequent irrigated cash crops.

Lawrence Berkeley National Laboratory (LBNL, Berkeley Lab) is a multi-program scientific facility operated by the University of California (UC) for the U.S. Department of Energy (DOE). Berkeley Lab’s research is focused on the physical, biological, environmental, and computational sciences, with the objective of delivering scientific knowledge and discoveries pertinent to DOE’s mission. This annual report describes environmental protection activities and potential impacts resulting from LBNL operations conducted in 2018. The format and content of this report satisfy the requirements of both DOE Order 231.1B, Administrative Change 1 (Environment, Safety, and Health Reporting) and the operating contract between UC and DOE (DOE Contract No. DE-AC02-05CH11231, also known as Contract 31).LBNL activities are planned and conducted with full regard to protecting employees, the public, and the environment, as well as complying with all applicable environmental, safety, and health laws and regulations. As presented in Chapter 2, Berkeley Lab implements an Environmental Management System (EMS) to oversee environmental compliance activities and continually improve overall environmental performance while maintaining operational capability and sustaining its overall mission.The effectiveness of the EMS and environmental programs is reviewed annually as part of the performance evaluation process of Contract 31. For fiscal year (FY) 2018, which began October 1, 2017, and ended September 30, 2018, the EMS was given a performance rating of B plus for its management of environmental activities (on a scale from A plus as the highest grade, to F as the lowest). The measurement and rating system was developed jointly by Berkeley Lab, UC, and DOE. The FY 2018 rating was based on how Berkeley Lab met the objective in DOE’s FY 2018 Performance Evaluation and Measurement Plan (Appendix B in Contract 31, Section J) of providing an efficient and effective EMS. Six significant accomplishments, which ranged from effective teaming on projects and with regulatory agencies to improved program assessment approaches, were factors in the rating.The EMS was also graded through the federal Office of Management and Budget’s annual EMS performance metrics, in which a reporting scorecard rates elements of the International Organization for Standardization (ISO) 14001 standard and the degree of integration between the EMS and Berkeley Lab’s sustainable practices. Overall scores fall into one of three categories: green (highest), yellow (middle), or red (lowest). For FY 2018, Berkeley Lab received a score of green. A week-long formal conformity audit of the EMS was conducted at the end of July by a qualified external party, as is required every three years. The audit team found that Berkeley Lab’s EMS continues to conform to the ISO standard with no major nonconformance.An overview of environmental protection and restoration programs is provided in Chapter 3, including information about compliance activities, operating permits, and regulatory agency inspections and audits that occurred during 2018. Twenty-one minor violations and two Class II violations were issued during agency inspections of programs governing aboveground and underground storage tanks, hazardous waste treatment units, hazardous waste storage areas, hazardous materials management, and wastewater, stormwater, and air emission sources.This report also includes information on environmental monitoring performed in 2018 (Chapter 4). The results of these monitoring activities confirmed that groundwater cleanup actions have been effective in reducing concentrations of volatile organic compounds (VOCs) in the groundwater, although concentrations appear to be reaching asymptotic levels in some areas. Site groundwater plumes are stable or are attenuating, and VOCs are not migrating off site. All emissions and discharges from LBNL operations were within environmental compliance release limits except oxides of nitrogen and carbon monoxide from boilers (under 5 million BTUs) from Buildings 2, 66, and 88.The radiological dose assessments (Chapter 5) performed in 2018 concluded that the maximum potential dose to a hypothetical resident from Berkeley Lab’s airborne radionuclide releases was approximately 0.04% of the DOE andU.S. Environmental Protection Agency annual limit of 10 millirem per year (mrem/yr); the potential dose from all radiation sources at Berkeley Lab was approximately 0.15% of the average natural background radiation dose of 310 mrem/yr in the United States, and about 0.5% of the DOE annual limit of 100 mrem/yr from all sources.

This paper discusses the possibility of deploying automated guided vehicle (AGV) technology in a company's production hall. Chronometric measurements of material handling and people handling were performed. The handling processes were divided into five sub-processes, which were analysed in terms of production line operation, distance, and carrying capacity of the automated guided vehicles. Based on the measurements, we found that it was necessary to use four vehicles for handling in the foam production hall. The company is applying this automation project to foams, and after successful testing, plans to continue with automation for leather upholstery. To ensure the correct chronometric results, we measured the distances between each workstation on the production floor at the company. Based on an analysis of material handling on the production lines, we evaluated that there is a possibility of applying AGVs on the entire production floor. We analysed the volumes of material transfer and the possibilities of interconnection within the existing material handling in the enterprise. Complications arise when deploying AGVs in the plant because the handling to the production lines is not only provided by the parent company, but also by the component suppliers themselves. Based on this observation, we have identified potential collision points within the operation between automated guided vehicles and other material handling equipment or people. For this reason, we deployed one more AGV on the handling routes to prevent unwanted collisions. This means that a human would be able to perform even more processes than a machine and can circulate 80 times, where a machine under the same conditions would only perform the entire circulation 57 times. There is room here to use humans for other processes and to automate the handling of goods, although it introduces delays that can be eliminated by deploying additional automated guided vehicles. This opens room for further research questions on how these vehicles can be deployed, even in a small space, and how existing material handling can be automated. [ABSTRACT FROM AUTHOR]

Self-healing, thermoresponsive hydrogels with a triple network (TN) were obtained by copolymerizing N-isopropyl acryl amide (NiPAAm) with polyvinyl alkohol (PVA) functionalized with methacrylic acid and N,N′-methylene bis(acryl amide) crosslinker in the presence of low amounts (

Purpose: This paper aims to investigate sustainability research collaborations between the City of Vancouver and the University of British Columbia (UBC), as a case study to better understand how to use city-university partnerships to advance effective urban sustainability policy and practices. The study compiles a basic inventory of partnerships since 2010, describes their benefits, areas for improvement, barriers to collaboration and proposes ways to increase and improve future collaborations. Design/methodology/approach: The study draws on an electronic survey completed by 58 individuals and interviews with 13 such participants who were faculty members and staff at UBC and Vancouver. Findings: Most collaborations responded to climate change in some way, were initiated through informal professional relationships and involved single departments in each organization. Projects ranged in size, duration and level of municipal funding. Although project participants were generally happy with past experiences, future collaborations could be improved by increasing leadership commitment and resources and producing more mutually beneficial outcomes. Barriers included lacking awareness of potential partners, difficulty aligning municipal needs with academic research interests and divergent expectations about project resources. The study recommends introducing formal processes to help identify overlapping interests and opportunities, enhance co-creation of projects and increase leadership and resources. Practical implications: The findings may inform the development and implementation of future city-university partnerships to advance sustainable policies and practices in urban areas. Originality/value: This paper contributes by reviewing experiences with city-university collaborations and offering evidence-based recommendations to improve them, thereby increasing opportunities for more effective urban sustainability solutions.

Nanofiber membranes (NFMs) coated with noble metals are intensively researched for various applications such as wearable electronics, environmental sensors, and point of care diagnostics. To achieve the desired functionality while minimizing costs, a combination of facile coating methods and accurate microstructural designs is required, but remains elusive. Herein, novel conductive and porous membranes are designed based on a facile and scalable approach to fabricating conformally coated gold layers on electrospun PVDF fibers (Au-PVDF-NFMs) via electroless plating. The deposition of a conformal and fully interconnected gold layer with an average thickness of circa 38 nm on the surface of nanofibers is confirmed by systematic characterizations. The high-conjunction gold layers endows a high electrical conductivity to the membranes, yielding a low sheet resistance of 1.2 Ω/sq. In addition, the membranes show integrated functionalities such as hydrophobicity and gas permeability. Notably, the NFMs also show excellent mechanical durability under both stretching and bending, with negligible conductivity losses after 1000 test cycles. Thanks to these properties, the Au-PVDF-NFMs demonstrates practical suitability as gas diffusion electrodes (GDEs) for electrochemical CO2 reduction. The Au-PVDF-NFMs exhibit a substantial Faradaic efficiency towards CO, as high as ∼ 85 % at −0.7 V vs reversible hydrogen electrode (RHE), and are able to reach current densities of 100 mA cm−2 at −0.95 V versus RHE.

Lawrence Berkeley National Laboratory (LBNL, Berkeley Lab) is a multi-program scientific facility operated by theUniversity of California (UC) for the U.S. Department of Energy (DOE). Berkeley Lab’s research is focused on thephysical, biological, environmental, and computational sciences with the objective of delivering scientificknowledge and discoveries pertinent to DOE’s mission. This annual report describes environmental protectionactivities and potential impacts resulting from LBNL operations conducted in 2017. The format and content of thisreport satisfy the requirements of both DOE Order 231.1B, Administrative Change 1 (Environment, Safety, andHealth Reporting) and the operating contract between UC and DOE (DOE Contract No. DE-AC02-05CH11231, alsoknown as Contract 31).Activities are planned and conducted with full regard to protecting employees, the public, and the environment, aswell as complying with all applicable environmental, safety, and health laws and regulations. Berkeley Labimplements an Environmental Management System (EMS) to oversee these compliance activities and continuallyimprove overall environmental performance while maintaining operational capability and sustaining its overallmission.The effectiveness of the EMS and environmental programs is reviewed annually as part of the performanceevaluation process of Contract 31. For fiscal year (FY) 2017, which began October 1, 2016, and ended September30, 2017, the EMS was given a performance rating of B plus for its management of environmental activities (on ascale from A plus as the highest grade to F as the lowest). The measurement and rating system was developedjointly by Berkeley Lab, UC, and DOE. The FY 2017 rating was based on how Berkeley Lab met the objective inDOE’s FY 2017 Performance Evaluation and Measurement Plan (Appendix B in Contract 31, Section J) of providingan efficient and effective EMS. Six significant accomplishments, which ranged from effective teaming on projectsand with regulatory agencies to improved program assessment approaches, were factors in the rating.The EMS was also graded through the federal Office of Management and Budget’s annual EMS performancemetrics, in which a reporting scorecard rates elements of the International Organization for Standardization (ISO)14001 standard and the degree of integration between the EMS and Berkeley Lab’s sustainable practices. Overallscores fall into one of three categories: green (highest), yellow (middle), or red (lowest). For FY 2017, Berkeley Labreceived a score of green, as described in more detail in Chapter 2.An overview of environmental protection and restoration programs is provided (Chapter 3), including informationabout compliance activities, operating permits, and regulatory agency inspections that occurred during 2017.Thirteen minor violations issued during City of Berkeley inspections of above and underground storage tanks,treatment units, and hazardous waste storage areas are discussed in this chapter.This report also includes information on environmental monitoring performed in 2017 (Chapter 4). The results ofthese monitoring activities confirmed that groundwater cleanup actions continue to show improving conditions,and all emissions and discharges from LBNL operations were within environmental compliance release limits, withthe exception of some stormwater discharges. Most stormwater discharges measured throughout the LBNL sitefall within acceptable levels established by the state’s stormwater permit; however, iron and aluminum exceededNumeric Action Levels. To reduce iron and aluminum discharge levels, Berkeley Lab is aggressively implementingcontrols such as construction of asphaltic berms and check dams to restrain and filter runoff to storm drains, andinstallation of filtration units in storm drain basins to collect sediment and absorb metal contaminants.The radiological dose assessments (Chapter 5) performed in 2017 concluded that the maximum potential dose to ahypothetical resident from Berkeley Lab’s airborne radionuclide releases was approximately 0.1% of the DOE andU.S. Environmental Protection Agency annual limit of 10 millirem per year (mrem/yr); the potential dose from allradiation sources at Berkeley Lab was approximately 0.06% of the average natural background radiation dose of310 mrem/yr in the United States, and about 0.2% of the DOE annual limit of 100 mrem/yr from all sources.