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Energy conservation in microorganisms is classically categorized into respiration and fermentation; however, recent work shows some species can use mixed or alternative bioenergetic strategies. We explored the use of extracellular electron transfer for energy conservation in diverse lactic acid bacteria (LAB), microorganisms that mainly rely on fermentative metabolism and are important in food fermentations. The LAB Lactiplantibacillus plantarum uses extracellular electron transfer to increase its NAD+/NADH ratio, generate more ATP through substrate-level phosphorylation, and accumulate biomass more rapidly. This novel, hybrid metabolism is dependent on a type-II NADH dehydrogenase (Ndh2) and conditionally requires a flavin-binding extracellular lipoprotein (PplA) under laboratory conditions. It confers increased fermentation product yield, metabolic flux, and environmental acidification in laboratory media and during kale juice fermentation. The discovery of a single pathway that simultaneously blends features of fermentation and respiration in a primarily fermentative microorganism expands our knowledge of energy conservation and provides immediate biotechnology applications.

The onset of COVID-19 required drastic changes on how students interacted in EE-Emerge, a course where the students design and build exhibits demonstrating engineering to the public. COVID-19 was used as an opportunity to expose students on how teams in industry collaborate effectively on a project remotely across time zones, and how to communicate their results on sites like GitHub and Hackster.

In this work, the online offering of a sophomore electrical and computer engineering hands-on course at UC Davis during COVID-19 pandemic is discussed. In response to California's social distancing guidelines, the course was abruptly moved from in-person to remote instruction. To overcome the challenges inherent in remote instruction, we employed novel policies, "Boost Points" (BP) and "Student Assistants" (SA), to incentivize early action on lab assignments and interaction between students. We present survey and participation data that show students favor these techniques. Finally, we outline future directions for SA/BP in lab-based circuits courses.

Real-time process metrics are standard for the majority of fermentation-based industries but have not been widely adopted by the wine industry. In this study, replicate fermentations were conducted with temperature as the main process parameter and assessed via in-line Oxidation Reduction Potential (ORP) probes and at-line profiling of phenolics compounds by UV-Vis spectroscopy. The California and Oregon vineyards used in this study displayed consistent vinification outcomes over five vintages and are representative of sites producing faster- and slower-fermenting musts. The selected sites have been previously characterized by fermentation kinetics, elemental profile, phenolics, and sensory analysis. ORP probes were integrated into individual fermentors to record how ORP changed throughout the fermentation process. The ORP profiles generally followed expected trends with deviations revealing previously undetectable process differences between sites and replicates. Site-specific differences were also observed in phenolic and anthocyanin extraction. Elemental composition was also analyzed for each vineyard, revealing distinctive profiles that correlated with the fermentation kinetics and may influence the redox status of these wines. The rapid ORP responses observed related to winemaking decisions and yeast activity suggest ORP is a useful process parameter that should be tracked in addition to Brix, temperature, and phenolics extraction for monitoring fermentations.

Dedicated lactation rooms are a modern development as mothers return to work while still providing breastmilk to their absent infants. This study describes the built environment microbiome of lactation rooms and daycares, and explores the influence of temperature and humidity on the microbiome of lactation rooms. Sterile swabs were used to collect samples from five different sites in lactation rooms at University of California, Davis and from five different sites in daycares located in Davis, California. DNA from the swabs was extracted and the V4 region of the 16S rRNA gene was sequenced using Illumina MiSeq. Temperature and relative humidity data were collected on a subset of the lactation rooms. Sampled lactation rooms could be either dedicated lactation rooms or could also serve other functions (e.g., combined lactation room and restroom lounge). The majority of sequence reads were identified as belonging to family Moraxellaceae, with 73% of all reads included in analysis identified as an unknown species of Acinetobacter. Alpha diversity was analyzed using the Shannon index, while beta diversity was analyzed using unweighted and weighted UniFrac distance. The Jaccard distance was used to measure amount of change at sampling locations between time points for analysis of the impact of temperature and humidity on the microbiome. There were significant differences in the beta diversity of the microbiome of lactation rooms by room type. There were also significant differences in the beta diversity of the microbiome by sample collection location. There were no significant differences in either alpha or beta diversity associated with room temperature or humidity. Additional studies are needed to understand if the differences in lactation room type may result in differences in the breastmilk microbiome of milk collected in those rooms, and to what extent any such differences may influence the infant microbiome.

Collagen is a biological macromolecule capable of second harmonic generation, allowing label-free detection in tissues; in addition, molecular orientation can be determined from the polarization dependence of the second harmonic signal. Previously we reported that in-plane orientation of collagen fibrils could be determined by modulating the polarization angle of the laser during scanning. We have now extended this method so that out-of-plane orientation angles can be determined at the same time, allowing visualization of the 3-dimensional structure of collagenous tissues. This approach offers advantages compared with other methods for determining out-of-plane orientation. First, the orientation angles are directly calculated from the polarimetry data obtained in a single scan, while other reported methods require data from multiple scans, use of iterative optimization methods, application of fitting algorithms, or extensive post-optical processing. Second, our method does not require highly specialized instrumentation, and thus can be adapted for use in almost any nonlinear optical microscopy setup. It is suitable for both basic and clinical applications. We present three-dimensional images of structurally complex collagenous tissues that illustrate the power of such 3-dimensional analyses to reveal the architecture of biological structures.

Most wine fermentations are completed in successive batches during a 2 month harvest period. Red wine fermentations are usually completed in 10 to 14 days, while white wine fermentations are completed in 21 to 24 days. The demand for resources—equipment, water, energy, labor, etc.—in a short time motivates the precise, automated control of the fermentation process. While the effects of temperature on wine chemistry are well studied, few advanced control strategies have been developed for the precise control of temperature for wine chemistry research. In this study, a nonlinear model predictive controller (NMPC) was developed to determine the temperature to achieve the desired fermentation rate. The controller was combined with a pulse cooling and heating strategy to improve the energy efficiency of temperature control. The feasibility of this approach is demonstrated by simulations and experiments in 15 L fermentations.

Energy conservation in microorganisms is classically categorized into respiration and fermentation; however, recent work shows some species can use mixed or alternative bioenergetic strategies. We explored the use of extracellular electron transfer for energy conservation in diverse lactic acid bacteria (LAB), microorganisms that mainly rely on fermentative metabolism and are important in food fermentations. The LAB Lactiplantibacillus plantarum uses extracellular electron transfer to increase its NAD+/NADH ratio, generate more ATP through substrate-level phosphorylation, and accumulate biomass more rapidly. This novel, hybrid metabolism is dependent on a type-II NADH dehydrogenase (Ndh2) and conditionally requires a flavin-binding extracellular lipoprotein (PplA) under laboratory conditions. It confers increased fermentation product yield, metabolic flux, and environmental acidification in laboratory media and during kale juice fermentation. The discovery of a single pathway that simultaneously blends features of fermentation and respiration in a primarily fermentative microorganism expands our knowledge of energy conservation and provides immediate biotechnology applications.

Combined with real-time monitoring of density and temperature, the control of the redox potential provides a new approach to influencing cell metabolism during growth, cell viability and non-growing yeast activity in wine fermentations. Prior research indicates that the problem of sluggish and incomplete fermentation can be alleviated by maintaining a constant redox potential during the ethanol fermentation. A secondary trait of hydrogen sulfide formation from elemental sulfur also seems to be associated with the development of low redox potentials during fermentation and this might be prevented by the deliberate control of redox potentials in a certain range. While the control of the redox potential during wine fermentations has been demonstrated previously at the research scale (100 L), the ability to control it in larger volumes typically seen in commercial conditions remained unanswered. Wine fermentations from the same load of Cabernet Sauvignon grapes from the 2021 harvest were conducted at three volumes: 100 L and 1500 L in a research winery and 10,000 L in a commercial winery. Using only pulses of air delivery, the redox potential was successfully controlled to −40 mV referenced to a silver/silver chloride electrode throughout the fermentations, at all scales. This appears to be the first published result of a controlled fermentation trial that includes the commercial scale and demonstrates the scalability of control of redox potential in wine fermentations.

An in-line color and total phenolic sensor is described to track the color and total phenol evolution during red wine fermentations. The sensor uses multiple light-emitting diodes (LEDs) spanning the ultraviolet and visible spectrum, in particular 280 and 525 nm. The performance of phenolic sensor was evaluated by analyzing fermentation samples collected from multiple red wine fermentations performed during the 2012 season. The study confirmed that the LED phenolic sensor measurements strongly correlate with measurements performed with a reference UV-vis spectrophotometer and that in-line measurements can be made in a practical manner after removal of yeast and pulp with a 2.0 µm filter. The use of a 100 µm path-length flow cell avoids the need for dilution, making in-line measurements possible. The sensor provides in-line measurement on the evolution of the total phenolic content and color extraction patterns during red wine fermentations.

Prostate cancer is the commonest non-cutaneous cancer in males and frequently metastasizes to nodal and skeletal tissues. Metastases to soft tissue viscera such as lung and liver are associated with decreased overall survival compared to nodal and skeletal metastases despite androgen deprivation and chemotherapy with palliative intent.We present a case with complete resolution of lung metastases after 225Ac-PSMA targeted alpha endoradiotherapy in a treatment naïve patient with metastatic prostate cancer. Our case gives preliminary clinical support for the efficacy of 225Ac-PSMA therapy in lung metastases.

Photoswitchable spiropyran has been conjugated to the crowned ring system DO3A, which improves its solubility in dipolar and polar media and stabilizes the merocyanine isomer. Adding the lanthanide ion gadolinium(III) to the macrocyclic ring system leads to a photoresponsive magnetic resonance imaging contrast agent that displays an increased spin-lattice relaxation time (T₁) upon visible light stimulation. In this work, the photoresponse of this photochromic molecule to weak light illumination using blue and green light emitting diodes was investigated, simulating the emission spectra from bioluminescent enzymes. Photon emission rate of the light emitting diodes was changed, from 1.75 × 10¹⁶ photons·s⁻¹ to 2.37 × 10¹² photons·s⁻¹. We observed a consistent visible light-induced isomerization of the merocyanine to the spiropyran form with photon fluxes as low as 2.37 × 10¹² photons·s⁻¹ resulting in a relaxivity change of the compound. This demonstrates the potential for use of the described imaging probes in low light level applications such as sensing bioluminescence enzyme activity. The isomerization behavior of gadolinium(III)-ion complexed and non-complexed spiropyran-DO3A was analyzed in water and ethanol solution in response to low light illumination and compared to the emitted photon emission rate from over-expressed Gaussia princeps luciferase.

The sum-frequency spectroscopy signatures of NH-(amide A) and C = O (amide I) groups, the amide segments in all proteins, are measured in thin films that consist of an ensemble of right-handed, helical poly-gamma-benzyl-L-glutamate (PBLG) macromolecules that are endgrafted and self-organized into a monomolecular film with a large degree of unidirectional order. Distinct sum-frequency spectral signatures associated with the amide A and the amide I bands are observed because of a strong noncentro-symmetry produced by intra- and intermolecular forces. Hydrogen bonding self-organizes amino and acidic groups within the molecular helical scaffold. In an endgrafted thin film, repulsive electrostatic forces between PBLG macromolecules stabilize the organization between molecules. The average orientation of the PBLG chain was measured. Imaging scans using sum-frequency generation, complemented by atomic force microscopy, were used to investigate the uniformity of orientation of the PBLG chains.

The dielectric properties are reported for nanoporous thin films of poly(methyl silsesquioxane) (MSSQ) for use as an ultralow, dielectric intermetal insulator. Direct experimental conformation is provided that the films have low dielectric constants with low loss up to 10 GHz. Low-frequency measurements are also reported.

Real-time process metrics are standard for the majority of fermentation-based industries but have not been widely adopted by the wine industry. In this study, replicate fermentations were conducted with temperature as the main process parameter and assessed via in-line Oxidation Reduction Potential (ORP) probes and at-line profiling of phenolics compounds by UV-Vis spectroscopy. The California and Oregon vineyards used in this study displayed consistent vinification outcomes over five vintages and are representative of sites producing faster- and slower-fermenting musts. The selected sites have been previously characterized by fermentation kinetics, elemental profile, phenolics, and sensory analysis. ORP probes were integrated into individual fermentors to record how ORP changed throughout the fermentation process. The ORP profiles generally followed expected trends with deviations revealing previously undetectable process differences between sites and replicates. Site-specific differences were also observed in phenolic and anthocyanin extraction. Elemental composition was also analyzed for each vineyard, revealing distinctive profiles that correlated with the fermentation kinetics and may influence the redox status of these wines. The rapid ORP responses observed related to winemaking decisions and yeast activity suggest ORP is a useful process parameter that should be tracked in addition to Brix, temperature, and phenolics extraction for monitoring fermentations.

Abstract Collagen is a biological macromolecule capable of second harmonic generation, allowing label-free detection in tissues; in addition, molecular orientation can be determined from the polarization dependence of the second harmonic signal. Previously we reported that in-plane orientation of collagen fibrils could be determined by modulating the polarization angle of the laser during scanning. We have now extended this method so that out-of-plane orientation angles can be determined at the same time, allowing visualization of the 3-dimensional structure of collagenous tissues. This approach offers advantages compared with other methods for determining out-of-plane orientation. First, the orientation angles are directly calculated from the polarimetry data obtained in a single scan, while other reported methods require data from multiple scans, use of iterative optimization methods, application of fitting algorithms, or extensive post-optical processing. Second, our method does not require highly specialized instrumentation, and thus can be adapted for use in almost any nonlinear optical microscopy setup. It is suitable for both basic and clinical applications. We present three-dimensional images of structurally complex collagenous tissues that illustrate the power of such 3-dimensional analyses to reveal the architecture of biological structures.

The factors impacting the adoption of mobile enterprise applications (MEAs) are important to understand if the value of using these applications is to materialize as improved business performance. By means of a review of the literature, the conceptual design of a model, a survey, and qualitative analysis, this mixed method study examined the factors which influence the adoption of three MEAs in the insurance industry. Interesting findings include the importance of willingness to fund devices on the adoption by users and the importance of job relevance and the location dependency of the MEAs on their usefulness. These findings are of relevance to researchers and organizations intending on deploying MEAs and practitioners should pay attention to the factors which can influence user acceptance of MEAs.

Dedicated lactation rooms are a modern development as mothers return to work while still providing breastmilk to their absent infants. This study describes the built environment microbiome of lactation rooms and daycares, and explores the influence of temperature and humidity on the microbiome of lactation rooms. Sterile swabs were used to collect samples from five different sites in lactation rooms at University of California, Davis and from five different sites in daycares located in Davis, California. DNA from the swabs was extracted and the V4 region of the 16S rRNA gene was sequenced using Illumina MiSeq. Temperature and relative humidity data were collected on a subset of the lactation rooms. Sampled lactation rooms could be either dedicated lactation rooms or could also serve other functions (e.g., combined lactation room and restroom lounge). The majority of sequence reads were identified as belonging to family Moraxellaceae, with 73% of all reads included in analysis identified as an unknown species of Acinetobacter. Alpha diversity was analyzed using the Shannon index, while beta diversity was analyzed using unweighted and weighted UniFrac distance. The Jaccard distance was used to measure amount of change at sampling locations between time points for analysis of the impact of temperature and humidity on the microbiome. There were significant differences in the beta diversity of the microbiome of lactation rooms by room type. There were also significant differences in the beta diversity of the microbiome by sample collection location. There were no significant differences in either alpha or beta diversity associated with room temperature or humidity. Additional studies are needed to understand if the differences in lactation room type may result in differences in the breastmilk microbiome of milk collected in those rooms, and to what extent any such differences may influence the infant microbiome.

Most wine fermentations are completed in successive batches during a 2 month harvest period. Red wine fermentations are usually completed in 10 to 14 days, while white wine fermentations are completed in 21 to 24 days. The demand for resources—equipment, water, energy, labor, etc.—in a short time motivates the precise, automated control of the fermentation process. While the effects of temperature on wine chemistry are well studied, few advanced control strategies have been developed for the precise control of temperature for wine chemistry research. In this study, a nonlinear model predictive controller (NMPC) was developed to determine the temperature to achieve the desired fermentation rate. The controller was combined with a pulse cooling and heating strategy to improve the energy efficiency of temperature control. The feasibility of this approach is demonstrated by simulations and experiments in 15 L fermentations. [ABSTRACT FROM AUTHOR]