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Viral Clearance of Cupric-Modified Phyllosilicate Minerals Against Enveloped and Non-Enveloped Viruses
Get PDFThe effectiveness of copper-based composites, specifically cupric ion (Cu2+)-modified phyllosilicate minerals, was evaluated in reducing the concentration of infectious agents in the environment while minimizing metal ion release. The phyllosilicate minerals, vermiculite, exfoliated and unexfoliated, and sepiolite, all modified with Cu2+, were compared with copper oxide for their antiviral activity against non-enveloped porcine parvovirus (PPV) and enveloped human coronavirus 229E (HCoV). Sepiolite effectively removed PPV and HCoV from the solution, regardless of Cu2+ presence, while vermiculite showed substantial viral clearance only when Cu2+ was present. The kinetics of viral clearance was fast, with complete clearance within one hour in many cases. To better understand the mechanism of virus clearance, EDTA was added at different times during the clearance study for PPV. EDTA prevented virus clearance in all vermiculite samples, whereas sepiolite containing copper still demonstrated substantial virus clearance. The addition of BSA before the virus binding was able to block binding in all cases. It was determined that binding is the key mechanism, and PPV can be eluted from the minerals with EDTA and still be infectious. This study provides the potent antiviral mechanisms of Cu2+-modified phyllosilicate minerals, offering insights for designing paints and plastics for high-touch surfaces to reduce viral transmission and enhance public health significantly
A Standards Perspective on Genomic Data Reusability and Reproducibility
Get PDFGenomic and metagenomic sequence data provides an unprecedented ability to re-examine findings, offering a transformative potential for advancing research, developing computational tools, enhancing clinical applications, and fostering scientific collaboration. However, effective and ethical reuse of genomics data is hampered by numerous technical and social challenges. The International Microbiome and Multi’Omics Standards Alliance (IMMSA, https://www.microbialstandards.org/) and the Genomic Standards Consortium (GSC, https://gensc.org) hosted a 5-part seminar series “A Year of Data Reuse” in 2024 to explore challenges and opportunities of data reuse and reproducibility across disparate domains of the genomic sciences. Addressing these challenges will require a multifaceted approach, including common metadata reporting, clear communication, standardized protocols, improved data management infrastructure, ethical guidelines, and collaborative policies that prioritize transparency and accessibility. We offer strategies to enable responsible and technically feasible data reuse, recognition of data reproducibility challenges, and emphasizing the importance of cross-disciplinary efforts in the pursuit of open science and data-driven innovation
“Nothing About Us Without Us”: Post-Exertional Malaise (PEM) and the Challenge of Designing Activism for People with ME and Long Covid
No full textThis chapter explores the unique problem experienced by communities of people with debilitating diseases who must combat the epistemic injustice they experience in order to improve their situation. The author draws on activism by people living with myalgic encephalomyelitis (ME) and Long Covid to explore how designers can create accessible forms of protest for people with disabilities. The #MillionsMissing campaigns created by #MEAction serve as a case study that shows how activist participation can help people understand and enact social justice principles. This case study highlights how complex chronic diseases facilitate embodied knowledge, which #MEAction uses to design protests that are accessible to people with ME and Long Covid
Porous micro-/nano-fibrous silver-coated polymeric scaffolds with tunable mechanical properties for wound healing applications
No full textElectro-spun scaffolds of poly(glycerol sebacate/poly(ε-caprolactone)(PGS/PCL) poly(methyl methacrylate)–poly(ε-caprolactone)(PMMA/PCL) have been using for biomedical applications of tissues engineering due to their attractive thermal, optical, and mechanical properties. In this work, we fabricate both nano-/micro-fibrous scaffolds from a hybrid material composite of PMMA/PCL and PGS/PCL fiber using a standard electro-spinning method and coat one side of the scaffolds with silver nanoparticles (AgNPs). This method of AgNPs coating prevents the scaffold (substrate) from melting behavior, and AgNPs coating reduces the pore diameter and increases fiber diameter, which improves their thermo-mechanical properties. Thereafter, we compare the mechanical properties of pristine PGS/PCL scaffold polymers; PMMA/PCL polymers with the AgNPs-coated PGS/PCL, PMMA/PCL scaffolds. The PMMA/PCL composite fibrous scaffolds show a higher modulus (E), tensile strength (TS), and lower tensile strain without any post-processing. These AgNPs-coated composite fibrous scaffolds provide potential applications in biomedical research fields, such as in fabricating of surgical meshes, bandages, and Band-Aids. Further, the enhanced antibacterial activities of AgNPs, which are used as a coating to our hybrid composite scaffolds, contribute to wound healing
Leveraging GIS for policy design: Spatial analytics as a strategic tool
Get PDFWe examine how geographic information system (GIS) tools contribute to policy design. Most accounts suggest that they merely generate information and data that can be used to enhance policy choices, a “design of services” perspective. More recent studies, however, suggest that GIS tools can also be used as procedural policy instruments, that is, to improve decision-making by facilitating stakeholder co-design and co-production processes, or what can be referred to as the designing “for” services. The activities of 57 GIS-based policy innovation labs (PILs) are examined. Seven critical but underutilized co-production activities that contribute to the attainment of public value are identified
Least squares as random walks
No full textLinear least squares (LLS) is perhaps the most common method of data analysis, dating back to Legendre, Gauss and Laplace. Framed as linear regression, LLS is also a backbone of mathematical statistics. Here we report on an unexpected new connection between LLS and random walks. To that end, we introduce the notion of a random walk based on a discrete sequence of data samples (data walk). We show that the slope of a straight line which annuls the net area under a residual data walk equals the one found by LLS. For equidistant data samples this result is exact and holds for an arbitrary distribution of steps
Purification of a Non-enveloped Virus using Sequential Aqueous Two-phase Extraction
No full textVirus-based vaccines and therapies require a purification method that is both cost-effective and easily scalable. An aqueous two-phase system (ATPS) consisting of polyethylene glycol (PEG) and citrate salt has been proven to deliver high virus recoveries along with high impurity removal. However, these systems often place the virus into a viscous PEG-rich phase or at the two-phase interface, leading to difficulties in subsequent downstream processes. This study explored a second ATPS to extract the virus product back into the citrate-rich phase by changing the chemical conditions, a required step for future application of ATPS in industrial processes. ATPS performance was tested as a function of phase component concentration, phase component volume ratios, PEG molecular weight, salt type, pH, and glycine addition to identify the most impactful parameters for the extraction of non-enveloped porcine parvovirus (PPV). By shifting the pH, lowering phase component concentrations, and increasing the volume ratio of the citrate-rich phase between the first and second ATPS steps, 66% of infectious PPV was recovered with 2.0 logs of host cell protein removal and 1.0 logs of host cell DNA removal. Using a PEG molecular weight of 8 kDa enabled a pH shift between the first and second ATPS steps without precipitation. Glycine addition during the first step of ATPS and phosphate salt use during the second step of ATPS did not significantly increase the overall recovery. In future studies, the optimized process will be implemented for multiple viral vector types and continuously to demonstrate continuous and low-cost viral vector manufacturing
Multivariate degradation modeling using generalized cauchy process and application in life prediction of dye-sensitized solar cells
No full textRecently, the Generalized Cauchy (GC) process has been applied to capture a Long Memory (LM) phenomenon in product degradation modeling and life prediction. Compared with the traditional fractional Brownian motion that captures the LM using a single Hurst parameter, the GC process has two free parameters (Hurst and fractal dimension parameters) that flexibly capture both global LM and local irregularity. However, all existing GC-based degradation models are for a single Degradation Characteristic (DC). In this article, motivated by a real degradation problem of dye-sensitized solar cells that jointly exhibits multiple DCs, global LM, local irregularity and DC-wise cross-correlation, we propose a novel GC-based Multivariate Degradation Model (GC-MDM) to simultaneously capture the aforementioned effects. A maximum likelihood estimation approach is developed to estimate parameters of the GC-MDM. Subsequently, product life prediction based on the GC-MDM is developed. The proposed GC-MDM is validated through a simulation study and a physical experiment of dye-sensitized solar cells. Results show that the proposed GC-MDM fundamentally improves the life prediction accuracy in comparison with conventional degradation models which significantly misestimate the uncertainty of product life
Detection of Extended X-Ray Emission around the PeVatron Microquasar V4641 Sgr with XRISM
Get PDFA recent report on the detection of very-high-energy gamma rays from V4641 Sagittarii (V4641 Sgr) up to ≈0.8 PeV has made it the second confirmed “PeVatron” microquasar. Here we report on the observation of V4641 Sgr with X-Ray Imaging and Spectroscopy Mission (XRISM) in 2024 September. Thanks to the large field of view and low background, the CCD imager Xtend successfully detected for the first time X-ray extended emission around V4641 Sgr with a significance of ≳4.5σ and \u3e10σ based on our imaging and spectral analysis, respectively. The spatial extent is estimated to have a radius of 7′ ± 3′ (13 ± 5 pc at a distance of 6.2 kpc) assuming a Gaussian-like radial distribution, which suggests that the particle acceleration site is within ~10 pc of the microquasar. If the X-ray morphology traces the diffusion of accelerated electrons, this spatial extent can be explained by either an enhanced magnetic field (∼80 μG) or a suppressed diffusion coefficient (∼1027 cm2 s−1 at 100 TeV). The integrated X-ray flux, (4-6) × 10−12 erg s−1 cm−2 (2-10 keV), would require a magnetic field strength higher than the Galactic mean (≳8 μG) if the diffuse X-ray emission originates from synchrotron radiation and the gamma-ray emission is predominantly hadronic. If the X-rays are of thermal origin, the measured extension, temperature, and plasma density can be explained by a jet with a luminosity of ∼2 × 1039 erg s−1, which is comparable to the Eddington luminosity of this system
Influence of different aged RAPs on the long-term performance of emulsified asphalt cold recycled mixture
No full textEmulsified asphalt cold recycled mixture (CRM) has attracted more and more scholars’ attention due to its advantages of construction at ambient temperature and high-usage of reclaimed asphalt pavement (RAP). However, research on the role of the aged asphalt binder on the surface of RAP in CRM during long-term pavement service is insufficient. Hence, this work studied the influence of different aged RAPs on the long-term performance of CRM. Firstly, different aged RAPs (RAP-6, RAP-12 and RAP-18) were prepared artificially. Then, the CRMs with different aged RAPs were obtained and treated through a long-term performance simulation test. Finally, the blending condition of new-aged asphalt binder on the surface of RAP and the basic road performance of CRM during long-term curing were analyzed. The results indicate that, compared with the cold mix asphalt mixture without aged asphalt binder, the aged asphalt binder plays a favorable role in enhancing the indirect tensile strength (ITS), low temperature anti-cracking resistance and water stability of CRM, whereas it has a negative influence on the high temperature stability of CRM. Meanwhile, this favorable role of the aged asphalt binder to low temperature anti-cracking resistance becomes quite weak for the CRM containing RAP-18. Moreover, for different CRMs after the long-term performance simulation test, the blending degree of the new-aged asphalt binder is enhanced gradually, as well as the more severe the aging of the aged asphalt binder is, the more the high temperature stability and water stability of the corresponding CRM is. Interestingly, the CRM with RAP-12 shows better ITS and low temperature performance than the CRM with RAP-6 or RAP-18 in the long-term curing process