Lundsgaardharrison7099

In the current study, electron paramagnetic resonance (EPR) spectroscopy was employed to measure environmentally persistent free radicals (EPFRs) in the total particulate matter (TPM) of mainstream and sidestream TPM of conventional cigarettes and the TPM of e-cigarettes. Comparable concentrations of EPFRs were detected in both sidestream (8.05 ± 1.32) × 104 pmol/g and mainstream TPM (7.41 ± 0.85) × 104 pmol/g of conventional cigarettes. TPM exposure to air resulted in long-lived oxygen centered, secondary radicals with EPR g values of 2.0041 for mainstream and 2.0044 for sidestream. Surprisingly, despite no combustion process, the TPM from e-cigarettes (menthol flavor of NJOY and V2 brands) also contain EPFRs with g values of 2.0031-2.0033, characteristic of carbon centered radicals, while the radical signal in the vanilla flavor of V2 brand was remarkably similar to semiquinones in cigarette smoke with a higher g value (2.0063). The radical concentration in e-cigarettes was much lower as compared to tobacco TPM. Although the production of ROS generated by e-cigarettes is comparatively lower than ROS generated by conventional cigarettes, EPFRs in e-cigarettes appear to be more potent than those in tobacco TPM with respect to hydroxyl radical generation yield per unit EPFR. EPFRs in e-cigarette TPM may be a potential source of health impacts.Chain elongation is a process that produces medium chain fatty acids (MCFAs) such as caproic acid which is one of the promising products of carboxylate platform. This study analyzed the impact of bioaugmentation of heat treated anaerobic digester sludge with C. kluyveri (AS+Ck) on caproic acid production from mixed substrate (lactose, lactate, acetate and ethanol). It was compared with processes initiated with non-augmented heat treated anaerobic digester sludge (AS) and mono-culture of C. kluyveri (Ck). Moreover, stability of the chain elongation process was evaluated by performing repeated batch experiments. All bacterial cultures demonstrated efficient caproate production in the first batch cycle. After 18 days caproate concentration reached 9.06 ± 0.43, 7.86 ± 0.38 and 7.67 ± 0.37 g/L for AS, Ck and AS+Ck cultures, respectively. AS microbiome was enriched towards caproate production in the second cycle and showed the highest caproate concentration of 11.44 ± 0.47 g/L. On the other hand, bioaugmented culture showed the lowest caproate production in the second cycle (4.10 ± 0.30 g/L). Microbiome analysis in both, AS and AS+Ck culture samples, indicated strong enrichment towards the anaerobic order of Clostridia. Strains belonging to genera Sporanaerobacter, Paraclostridium, Haloimpatiens, Clostridium and Bacillus were dominating in the bioreactors.Young women in sub-Saharan Africa have the highest risk of human immunodeficiency virus (HIV) acquisition through sexual contact of all groups. Vaginal controlled release of antiretrovirals is a priority option for the prevention of sexual transmission of the virus in women. In this manuscript, bilayer films were prepared based on ethylcellulose and a natural polymer (xanthan or tragacanth gum) plasticized with glycerol and tributylcitrate for tenofovir-controlled release. The mechanical properties and microstructure of the blank films were characterized by texture analysis, Fourier transform infrared spectroscopy, and scanning electron microscopy. The loaded films were evaluated in simulated vaginal fluid through release and swelling studies and ex vivo mucoadhesion assessments. The results show that the preparation method produced bilayer films with adequate mechanical properties. The contribution of both layers allowed the sustained release of tenofovir and a mucoadhesion time of up to 360 h. The toxicity of the materials was evaluated in three cell lines of vaginal origin. The films constituted by ethylcellulose and xanthan gum in a 21 proportion (EX2-D) showed the longest mucoadhesion time, with 15 days of tenofovir-controlled release, zero toxicity, and optimal mechanical properties. These films are therefore a promising option for offering women a means of self-protection against the sexual transmission of HIV.The use of NMR spectroscopy has emerged as a premier tool to characterize the higher order structure of protein therapeutics and in particular IgG1 monoclonal antibodies (mAbs). Due to their large size, traditional 1H-15N correlation experiments have proven exceedingly difficult to implement on mAbs, and a number of alternative techniques have been proposed, including the one-dimensional (1D) 1H protein fingerprint by line shape enhancement (PROFILE) method and the two-dimensional (2D) 1H-13C methyl correlation-based approach. Both 1D and 2D approaches have relative strengths and weaknesses, related to the inherent sensitivity and resolution of the respective methods. To further increase the utility of NMR to the biopharmaceutical community, harmonized criteria for decision making in employing 1D and 2D approaches for mAb characterization are warranted. To this end, we have conducted an interlaboratory comparative study of the 1D PROFILE and 2D methyl methods on several mAbs samples to determine the degree to which each method is suited to detect spectral difference between the samples and the degree to which results from each correlate with one another. Results from the study demonstrate both methods provide statistical data highly comparable to one another and that each method is capable of complementing the limitations commonly associated with the other, thus providing a better overall picture of higher order structure.Using first-principles simulations, we surveyed the interactions between porous MoS2 monolayers in the 2H phase and 15 small molecules (H2, O2, H2O, H2S, CO, CO2, SO2, N2, NO, NO2, NH3, HF, HCl, CH4, and CH3OH). Four types of molecules including H2, O2, H2S, and NO2 directly dissociate and saturate the corners of the most common S-rimmed triangular pores, while other molecules only molecularly adsorb. The trisublayered structure of a MoS2 monolayer allows a new in-pore stable adsorption configuration in addition to the most studied above-pore adsorption configuration. Furthermore, the gas penetration pathways through the MoS2 membranes are no longer the conventional single-peak curve with one transition state like in the case of porous graphenes but are the "M"-shaped curve featuring two transition states connected by a stable in-pore adsorption state. The irreversible pore passivation via dissociative adsorption and reversible pore decoration by molecular adsorption will lead to very different separation performances of the MoS2 membranes, largely by changing the effective pore size. For example, the S-rimmed pores in the pore-3Mo2S membrane allow free pass of CH4 and CO2 molecules. If passivated by H atoms, the membrane can be used to separate gas mixtures like H2/CH4 and H2/CO2 with selectivities of 1091 and 1081, respectively. The permeance value of H2 is estimated to be about 0.15 mol m-2 s-1 Pa-1 at room temperature and 0.1 bar pressure drop across the membrane. In contrast, the medium strong adsorption of a SO2 molecule in the center of the pore will completely block the passage of CO2 and CH4, whose removal only needs heating. Our work reveals the complex behaviors of porous transition metal dichalcogenides (TMDs) toward guest molecules.Shape-shifting liquid crystal networks (LCNs) can transform their morphology and properties in response to external stimuli. These active and adaptive polymer materials can have impact in a diversity of fields, including haptic displays, energy harvesting, biomedicine, and soft robotics. Electrically driven transformations in LCN coatings are particularly promising for application in electronic devices, in which electrodes are easily integrated and allow for patterning of the functional response. The morphing of these coatings, which are glassy in the absence of an electric field, relies on a complex interplay between polymer viscoelasticity, liquid crystal order, and electric field properties. Morphological transformations require the material to undergo a glass transition that plasticizes the polymer sufficiently to enable volumetric and shape changes. Understanding how an alternating current can plasticize very stiff, densely cross-linked networks remains an unresolved challenge. Here, we use a nanoscale strain detection method to elucidate this electric-field-induced devitrification of LCNs. We find how a high-frequency alternating field gives rise to pronounced nanomechanical changes at a critical frequency, which signals the electrical glass transition. Across this transition, collective motion of the liquid crystal molecules causes the network to yield from within, leading to network weakening and subsequent nonlinear expansion. These results unambiguously prove the existence of electroplasticization. Fine-tuning the induced emergence of plasticity will not only enhance the surface functionality but also enable more efficient conversion of electrical energy into mechanical work.The COVID-19 pandemic is one of those global challenges that transcends territorial, political, ideological, religious, cultural, and certainly academic boundaries. Public health and healthcare workers are at the frontline, working to contain and to mitigate the spread of this disease. Although intervening biological and immunological responses against viral infection may seem far from the physical sciences and engineering that typically work with inanimate objects, there actually is much that can-and should-be done to help in this global crisis. In this Perspective, we convert the basics of infectious respiratory diseases and viruses into physical sciences and engineering intuitions, and through this exercise, we present examples of questions, hypotheses, and research needs identified based on clinicians' experiences. We hope researchers in the physical sciences and engineering will proactively study these challenges, develop new hypotheses, define new research areas, and work with biological researchers, healthcare, and public health professionals to create user-centered solutions and to inform the general public, so that we can better address the many challenges associated with the transmission and spread of infectious respiratory diseases.In modern manufacturing, it is a widely accepted limitation that the parts patterned by an additive or subtractive manufacturing process (i.e., a lathe, mill, or 3D printer) must be smaller than the machine itself that produced them. Once such parts are manufactured, they can be postprocessed, fastened together, welded, or adhesively bonded to form larger structures. We have developed a foaming prepolymer resin for lithographic additive manufacturing, which can be expanded after printing to produce parts up to 40× larger than their original volume. This allows for the fabrication of structures significantly larger than the build volume of the 3D printer that produced them. Complex geometries comprised of porous foams have implications in technologically demanding fields such as architecture, aerospace, energy, and biomedicine. This manuscript presents a comprehensive screening process for resin formulations, detailed analysis of printing parameters, and observed mechanical properties of the 3D-printed foams.