A segmentation clock patterns cellular differentiation in a bacterial biofilm.

Contrary to multicellular organisms that display segmentation during development, communities of unicellular organisms are believed to be devoid of such sophisticated patterning. Unexpectedly, we find that the gene expression underlying the nitrogen stress response of a developing Bacillus subtilis biofilm becomes organized into a ring-like pattern. Mathematical modeling and genetic probing of the underlying circuit indicate that this patterning is generated by a clock and wavefront mechanism, similar to that driving vertebrate somitogenesis. We experimentally validated this hypothesis by showing that predicted nutrient conditions can even lead to multiple concentric rings, resembling segments. We additionally confirmed that this patterning mechanism is driven by cell-autonomous oscillations. Importantly, we show that the clock and wavefront process also spatially patterns sporulation within the biofilm. Together, these findings reveal a biofilm segmentation clock that organizes cellular differentiation in space and time, thereby challenging the paradigm that such patterning mechanisms are exclusive to plant and animal development.

Magnesium Flux Modulates Ribosomes to Increase Bacterial Survival.

Bacteria exhibit cell-to-cell variability in their resilience to stress, for example, following antibiotic exposure. Higher resilience is typically ascribed to "dormant" non-growing cellular states. Here, by measuring membrane potential dynamics of Bacillus subtilis cells, we show that actively growing bacteria can cope with ribosome-targeting antibiotics through an alternative mechanism based on ion flux modulation. Specifically, we observed two types of cellular behavior: growth-defective cells exhibited a mathematically predicted transient increase in membrane potential (hyperpolarization), followed by cell death, whereas growing cells lacked hyperpolarization events and showed elevated survival. Using structural perturbations of the ribosome and proteomic analysis, we uncovered that stress resilience arises from magnesium influx, which prevents hyperpolarization. Thus, ion flux modulation provides a distinct mechanism to cope with ribosomal stress. These results suggest new approaches to increase the effectiveness of ribosome-targeting antibiotics and reveal an intriguing connection between ribosomes and the membrane potential, two fundamental properties of cells.

SnapShot: Electrochemical Communication in Biofilms.

The role of electricity in biological systems was first appreciated through electrical stimulation experiments performed by Luigi Galvani in the 18th century. These pioneering experiments demonstrated that the behavior of living tissues is governed by the flow of electrochemical species-an insight that gave rise to the modern field of electrophysiology. Since then, electrophysiology has largely remained a bastion of neuroscience. However, exciting recent developments have demonstrated that even simple bacteria residing in communities use electrochemical communication to coordinate population-level behaviors. These recent works are defining the emerging field of bacterial biofilm electrophysiology. To view this SnapShot, open or download the PDF.

Chromosomal Arrangement of Phosphorelay Genes Couples Sporulation and DNA Replication.

Genes encoding proteins in a common regulatory network are frequently located close to one another on the chromosome to facilitate co-regulation or couple gene expression to growth rate. Contrasting with these observations, here, we demonstrate a functional role for the arrangement of Bacillus subtilis sporulation network genes on opposite sides of the chromosome. We show that the arrangement of two sporulation network genes, one located close to the origin and the other close to the terminus, leads to a transient gene dosage imbalance during chromosome replication. This imbalance is detected by the sporulation network to produce cell-cycle coordinated pulses of the sporulation master regulator Spo0A∼P. This pulsed response allows cells to decide between sporulation and continued vegetative growth during each cell cycle spent in starvation. The simplicity of this coordination mechanism suggests that it may be widely applicable in a variety of gene regulatory and stress-response settings. VIDEO ABSTRACT.

Fabrication of InVO4/SnWO4 heterostructured photocatalyst for efficient photocatalytic degradation of tetracycline under visible light.

In the present study, novel InVO4/SnWO4 nanocomposites with different concentrations of SnWO4 were successfully prepared using a facile hydrothermal technique and investigated employing a wide range of analytical methods for efficient photocatalytic degradation of tetracycline (TC). X-ray diffraction analysis showed the presence of the orthorhombic phases of both InVO4 and SnWO4 in the composite catalyst. Dispersion of SnWO4 nanoplates over the InVO4 nanosheets enhanced the synergistic interactions, improving the separation of charge carriers and their transfer. Furthermore, the formation of heterostructure expanded the absorption range and promoted visible light harvesting. The TC degradation efficiency of InVO4/SnWO4 nanocomposite (5 mg loading of SnWO4) reached 97.13% in 80 min under visible light, with the kinetic rate constants 5.51 and 7.63 times greater than those of pure InVO4 and SnWO4, respectively. Additionally, the scavenger results proved that hydroxyl radicals and holes played a significant role in the photodegradation of TC. Furthermore, the electrochemical impedance spectroscopy (EIS) and transient photocurrent response analysis showed enhanced e-/h+ partition efficiency. Thus, the formation of heterostructure with strong synergistic interactions can effectively transfer the excited charge carriers and shorten the reunion rate. Accordingly, the InVO4/SnWO4 nanocomposites exhibited remarkable photocatalytic performance due to the increased number of charge carriers on the surface.

Chemoresistive Sensor Readout Circuit Design for Detecting Gases with Slow Response Time Characteristics.

Based on an analysis of the signal characteristics of gas sensors, this work presents a chemoresistive sensor readout circuit design for detecting gases with slow response time characteristics. The proposed readout circuit directly generates a reference voltage corresponding to the initial value of the gas sensor and extracts only the amount of gas concentration change in the sensor. Because the proposed readout circuit can adaptively regenerate the suitable reference voltage under various changing ambient conditions, it can alleviate the variation in output values at the same gas concentration caused by non-uniformities among gas sensors. Furthermore, this readout circuit effectively eliminates the initial value shifts due to the poor reproducibility of the gas sensor itself without requiring complex digital signal calibrations. This work focuses on a commercially viable readout circuit structure that can effectively obtain slow response gas information without requiring a large capacitor. The proposed readout circuit operation was verified by simulations using spectre in cadence simulation software. It was then implemented on a printed circuit board with discrete components to confirm the effectiveness with existing gas sensor systems and its commercial viability.

Engineering chloroplast development in rice through cell-specific control of endogenous genetic circuits.

The engineering of C4 photosynthetic activity into the C3 plant rice has the potential to nearly double rice yields. To engineer a two-cell photosynthetic system in rice, the rice bundle sheath (BS) must be rewired to enhance photosynthetic capacity. Here, we show that BS chloroplast biogenesis is enhanced when the transcriptional activator, Oryza sativa Cytokinin GATA transcription factor 1 (OsCGA1), is driven by a vascular specific promoter. Ectopic expression of OsCGA1 resulted in increased BS chloroplast planar area and increased expression of photosynthesis-associated nuclear genes (PhANG), required for the biogenesis of photosynthetically active chloroplasts in BS cells of rice. A further refinement using a DNAse dead Cas9 (dCas9) activation module driven by the same cell-type specific promoter, directed enhanced chloroplast development of the BS cells when gRNA sequences were delivered by the dCas9 module to the promoter of the endogenous OsCGA1 gene. Single gRNA expression was sufficient to mediate the transactivation of both the endogenous gene and a transgenic GUS reporter fused with OsCGA1 promoter. Our results illustrate the potential for tissue-specific dCas9-activation and the co-regulation of genes needed for multistep engineering of C4 rice.

Lactobacillus rhamnosus HDB1258 modulates gut microbiota-mediated immune response in mice with or without lipopolysaccharide-induced systemic inflammation.

BACKGROUND: Gut microbiota closely communicate in the immune system to maintain a balanced immune homeostasis in the gastrointestinal tract of the host. Oral administration of probiotics modulates gut microbiota composition. In the present study, we isolated Lactobacillus rhamnosus HDB1258, which induced tumor necrosis factor (TNF)-α and interleukin (IL)-10 expression in macrophages, from the feces of breastfeeding infants and examined how HDB1258 could regulate the homeostatic immune response in mice with or without lipopolysaccharide (LPS)-induced systemic inflammation. RESULTS: Oral administration of HDB1258 significantly increased splenic NK cell cytotoxicity, peritoneal macrophage phagocytosis, splenic and colonic TNF-α expression, TNF-α to IL-10 expression ratio, and fecal IgA level in control mice, while Th1 and Treg cell differentiation was not affected in the spleen. However, HDB1258 treatment significantly suppressed peritoneal macrophage phagocytosis and blood prostaglandin E2 level in mice with LPS-induced systemic inflammation. Its treatment increased LPS-suppressed ratios of Treg to Th1 cell population, Foxp3 to T-bet expression, and IL-10 to TNF-α expression. Oral administration of HDB1258 significantly decreased LPS-induced colon shortening, myeloperoxidase activity and NF-κB+/CD11c+ cell population in the colon, while the ratio of IL-10 to TNF-α expression increased. Moreover, HDB1258 treatment shifted gut microbiota composition in mice with and without LPS-induced systemic inflammation: it increased the Cyanobacteria and PAC000664_g (belonging to Bacteroidetes) populations and reduced Deferribacteres and EU622763_s group (belonging to Bacteroidetes) populations. In particular, PAC001066_g and PAC001072_s populations were negatively correlated with the ratio of IL-10 to TNF-α expression in the colon, while the PAC001070_s group population was positively correlated. CONCLUSIONS: Oral administered HDB1258 may enhance the immune response by activating innate immunity including to macrophage phagocytosis and NK cell cytotoxicity in the healthy host and suppress systemic inflammation in the host with inflammation by the modulation of gut microbiota and IL-10 to TNF-α expression ratio in immune cells.

Metabolic co-dependence gives rise to collective oscillations within biofilms.

Cells that reside within a community can cooperate and also compete with each other for resources. It remains unclear how these opposing interactions are resolved at the population level. Here we investigate such an internal conflict within a microbial (Bacillus subtilis) biofilm community: cells in the biofilm periphery not only protect interior cells from external attack but also starve them through nutrient consumption. We discover that this conflict between protection and starvation is resolved through emergence of long-range metabolic co-dependence between peripheral and interior cells. As a result, biofilm growth halts periodically, increasing nutrient availability for the sheltered interior cells. We show that this collective oscillation in biofilm growth benefits the community in the event of a chemical attack. These findings indicate that oscillations support population-level conflict resolution by coordinating competing metabolic demands in space and time, suggesting new strategies to control biofilm growth.

Development of breast phantoms using a 3D printer and glandular dose evaluation.

In this study, breast phantoms were fabricated by emulating glandular and adipose tissues separately using a three-dimensional (3D) printer. In addition, direct and quantitative glandular dose evaluations were performed. A quantitative method was developed to evaluate the glandular and adipose tissues separately when performing glandular dose evaluations. The variables used for glandular dose evaluation were breast thickness, glandular tissue ratio, and additional filter materials. The values obtained using a Monte Carlo simulation and those measured using a glass dosimeter were compared and analyzed. The analysis showed that as the glandular tissue ratio increased, the dose decreased by approximately 10%, which is not a significant variation. The comparison revealed that the simulated values of the glandular dose were approximately 15% higher than the measured values. The use of silver and rhodium filters resulted in a mean simulated dose of 1.00 mGy and 0.72 mGy, respectively, while the corresponding mean measured values were 0.89 mGy ± 0.03 mGy and 0.62 mGy ± 0.02 mGy. The mean glandular dose can be reliably evaluated by comparing the simulated and measured values.

Caffeic Acid Phenethyl Ester-Incorporated Radio-Sensitive Nanoparticles of Phenylboronic Acid Pinacol Ester-Conjugated Hyaluronic Acid for Application in Radioprotection.

We synthesized phenylboronic acid pinacol ester (PBPE)-conjugated hyaluronic acid (HA) via thiobis(ethylamine) (TbEA) linkage (abbreviated as HAsPBPE conjugates) to fabricate the radiosensitive delivery of caffeic acid phenetyl ester (CAPE) and for application in radioprotection. PBPE was primarily conjugated with TbEA and then PBPE-TbEA conjugates were conjugated again with hyaluronic acid using carbodiimide chemistry. CAPE-incorporated nanoparticles of HAsPBPE were fabricated by the nanoprecipitation method and then the organic solvent was removed by dialysis. CAPE-incorporated HAsPBPE nanoparticles have a small particle size of about 80 or 100 nm and they have a spherical shape. When CAPE-incorporated HAsPBPE nanoparticles were irradiated, nanoparticles became swelled or disintegrated and their morphologies were changed. Furthermore, the CAPE release rate from HAsPBPE nanoparticles were increased according to the radiation dose, indicating that CAPE-incorporated HAsPBPE nanoparticles have radio-sensitivity. CAPE and CAPE-incorporated HAsPBPE nanoparticles appropriately prevented radiation-induced cell death and suppressed intracellular accumulation of reactive oxygen species (ROS). CAPE and CAPE-incorporated HAsPBPE nanoparticles efficiently improved survivability of mice from radiation-induced death and reduced apoptotic cell death. We suggest that HAsPBPE nanoparticles are promising candidates for the radio-sensitive delivery of CAPE.

A Metal Artifact Reduction Method Using a Fully Convolutional Network in the Sinogram and Image Domains for Dental Computed Tomography.

The reconstruction quality of dental computed tomography (DCT) is vulnerable to metal implants because the presence of dense metallic objects causes beam hardening and streak artifacts in the reconstructed images. These metal artifacts degrade the images and decrease the clinical usefulness of DCT. Although interpolation-based metal artifact reduction (MAR) methods have been introduced, they may not be efficient in DCT because teeth as well as metallic objects have high X-ray attenuation. In this study, we investigated an effective MAR method based on a fully convolutional network (FCN) in both sinogram and image domains. The method consisted of three main steps: (1) segmentation of the metal trace, (2) FCN-based restoration in the sinogram domain, and (3) FCN-based restoration in image domain followed by metal insertion. We performed a computational simulation and an experiment to investigate the image quality and evaluated the effectiveness of the proposed method. The results of the proposed method were compared with those obtained by the normalized MAR method and the deep learning-based MAR algorithm in the sinogram domain with respect to the root-mean-square error and the structural similarity. Our results indicate that the proposed MAR method significantly reduced the presence of metal artifacts in DCT images and demonstrated better image performance than those of the other algorithms in reducing the streak artifacts without introducing any contrast anomaly.

OsMPK6 plays a critical role in cell differentiation during early embryogenesis in Oryza sativa.

The formation of body axes is the basis of morphogenesis during plant embryogenesis. We identified embryo-lethal mutants of rice (Oryza sativa) in which T-DNAs were inserted in OsMPK6 Embryonic organs were absent because their development was arrested at the globular stage. Similar to observations made with gle4, shootless, and organless, the osmpk6 mutations affected the initial step of cell differentiation. Expression of an apical-basal axis marker gene, OSH1, was reduced in the mutant embryos while that of the radial axes marker genes OsSCR and OsPNH1 was not detected. The signal for ROC1, a protodermal cell marker, was weak at the globular stage and gradually disappeared. Transcript levels of auxin and gibberellin biosynthesis genes were diminished in osmpk6 embryos. In addition, phytoalexin biosynthesis genes were down-regulated in osmpk6 and a major diterpene phytoalexin, momilactone A, did not accumulate in the mutant embryos. These results indicate that OsMPK6 begins to play a critical role during early embryogenesis, especially when the L1 radial axis is being formed.

Enhanced osteoinductivity of recombinant human bone morphogenetic protein-2 in combination with epidermal growth factor in a rabbit tibial defect model.

This study aims to explore the effect of recombinant human bone morphogenetic protein-2 (rhBMP-2) on bone formation when treated with epidermal growth factor (EGF) using human mesenchymal stem cells (hMSCs) and a rabbit tibial defect model. The rhBMP-2 (250 ng/ml)+EGF (10 ng/ml) group showed higher alkaline phosphatase (ALP) activity, ALP expression, increased calcium amount than rhBMP-2 group. In micro-CT and histology results of animal experiments, the rhBMP-2+EGF group showed more amount of bone bridging compared to the rhBMP-2 group. Among the 8-week groups, the rhBMP-2+EGF group showed significantly higher percent bone volume and trabecular number compared to the rhBMP-2 group. The combined treatment with EGF and rhBMP-2 induced significantly higher bone formation compared to that of rhBMP-2 only in both hMSCs and a rabbit tibial defect model. Therefore, EGF is expected to facilitate bone formation effect of rhBMP-2 when both factors are treated in combination.

Evaluating psychological anxiety in patients receiving radiation therapy using smartwatch.

PURPOSE: Patients undergoing radiation therapy (RT) often experience psychological anxiety that manifests as muscle contraction. Our study explored psychological anxiety in these patients by using biological signals recorded using a smartwatch. MATERIALS AND METHODS: Informed consent was obtained from participating patients prior to the initiation of RT. The patients wore a smartwatch from the waiting room until the conclusion of the treatment. The smartwatch acquired data related to heart rate features (average, minimum, and maximum) and stress score features (average, minimum, and maximum). On the first day of treatment, we analyzed the participants' heart rates and stress scores before and during the treatment. The acquired data were categorized according to sex and age. For patients with more than three days of data, we observed trends in heart rate during treatment relative to heart rate before treatment (HRtb) over the course of treatment. Statistical analyses were performed using the Wilcoxon signed-rank test and paired t-test. RESULTS: Twenty-nine individuals participated in the study, of which 17 had more than 3 days of data. During treatment, all patients exhibited elevated heart rates and stress scores, particularly those in the younger groups. The HRtb levels decreased as treatment progresses. CONCLUSION: Patients undergoing RT experience notable psychological anxiety, which tends to diminish as the treatment progresses. Early stage interventions are crucial to alleviate patient anxiety during RT.

Framework for dual-energy-like chest radiography image synthesis from single-energy computed tomography based on cycle-consistent generative adversarial network.

BACKGROUND: Dual-energy (DE) chest radiography (CXR) enables the selective imaging of two relevant materials, namely, soft tissue and bone structures, to better characterize various chest pathologies (i.e., lung nodule, bony lesions, etc.) and potentially improve CXR-based diagnosis. Recently, deep-learning-based image synthesis techniques have attracted considerable attention as alternatives to existing DE methods (i.e., dual-exposure-based and sandwich-detector-based methods) because software-based bone-only and bone-suppression images in CXR could be useful. PURPOSE: The objective of this study was to develop a new framework for DE-like CXR image synthesis from single-energy computed tomography (CT) based on a cycle-consistent generative adversarial network. METHODS: The core techniques of the proposed framework are divided into three categories: (1) data configuration from the generation of pseudo CXR from single energy CT, (2) learning of the developed network architecture using pseudo CXR and pseudo-DE imaging using a single-energy CT, and (3) inference of the trained network on real single-energy CXR. We performed a visual inspection and comparative evaluation using various metrics and introduced a figure of image quality (FIQ) to consider the effects of our framework on the spatial resolution and noise in terms of a single index through various test cases. RESULTS: Our results indicate that the proposed framework is effective and exhibits potential synthetic imaging ability for two relevant materials: soft tissue and bone structures. Its effectiveness was validated, and its ability to overcome the limitations associated with DE imaging techniques (e.g., increase in exposure dose owing to the requirement of two acquisitions, and emphasis on noise characteristics) via an artificial intelligence technique was presented. CONCLUSIONS: The developed framework addresses X-ray dose issues in the field of radiation imaging and enables pseudo-DE imaging with single exposure.

Association of metformin with cardiovascular and graft outcomes in kidney transplant recipients with posttransplantation diabetes mellitus.

Background: Posttransplantation diabetes mellitus (PTDM) is a crucial problem after kidney transplantation. We aimed to determine whether metformin affects cardiovascular and graft outcomes in patients with PTDM. Methods: This retrospective cohort study included 1,663 kidney transplant recipients without preexisting diabetes mellitus. The patients were divided into metformin and non-metformin groups, with matched propensity scores. We also estimated metformin's effect on percutaneous coronary intervention (PCI), major adverse cardiovascular events (MACEs), acute rejection, and graft failure. Results: Of 634 recipients with PTDM, 406 recipients were treated with metformin. The incidence of PCI was 2.4% and 7.1% in the metformin and non-metformin groups, respectively (p = 0.04). The metformin group exhibited a lower risk of PCI in Cox regression analyses (hazard ratio [HR], 0.27; 95% confidence interval [CI], 0.10-0.77; p = 0.014), especially in subgroups with male sex, age over 49 years (median), long-term metformin use (mean of ≥1,729 days), and simultaneous tacrolimus administration. Long-term metformin use was also associated with lower incidence of MACEs (HR, 0.09; 95% CI, 0.01-0.67; p = 0.02). Incidence of graft failure was 9.9% and 17.0% in the metformin and non-metformin groups, respectively (p = 0.046). Both long-term use and higher dose of metformin, as well as tacrolimus administration with metformin, were associated with a lower risk of graft failure (HR, 0.29; 95% CI, 0.11-0.75; p = 0.01; HR, 0.39; 95% CI, 0.18-0.85; p = 0.02; and HR, 0.39; 95% CI, 0.19-0.79; p = 0.009, respectively). Conclusion: Metformin use is associated with a decreased risk of developing coronary artery disease and better graft outcomes in PTDM.

Two AP2 family genes, supernumerary bract (SNB) and Osindeterminate spikelet 1 (OsIDS1), synergistically control inflorescence architecture and floral meristem establishment in rice.

Meristem identity is crucial in determining the inflorescence architecture of grass species. We previously reported that SUPERNUMERARY BRACT (SNB) regulates the transition of spikelet meristems into floral meristems in rice (Oryza sativa). Here we demonstrated that SNB and Oryza sativa INDETERMINATE SPIKELET 1 (OsIDS1) together play important roles in inflorescence architecture and the establishment of floral meristems. In snb osids1 double mutants, the numbers of branches and spikelets within a panicle are significantly decreased, and the transition to a floral meristem is further delayed compared with the snb single mutant. Expression analyses showed that SNB and OsIDS1 are required for spatio-temporal expression of B- and E-function floral organ identity genes in the lodicules. In addition, the AP2 family genes are important for determining the degree of ramification in branch meristems, regulating the spatio-temporal expression of spikelet meristem genes, such as FRIZZY PANICLE (FZP). Furthermore, overexpression of microRNA172 (miR172) causes reductions in SNB and OsIDS1 transcript levels, and phenotypes of the transgenic plants are more severe than for snb osids1. This indicates that additional gene(s) participate in the development of branch and floral meristems. Preferential expression of mature miR172s in the area around the spikelet meristems implies that depletion of the AP2 family genes in those meristems via miR172 is an important step in controlling inflorescence branching and the formation of floral organs.

The rice gene DEFECTIVE TAPETUM AND MEIOCYTES 1 (DTM1) is required for early tapetum development and meiosis.

Tapetum development and meiosis play crucial roles in anther development. Here we identified a rice gene, DEFECTIVE TAPETUM AND MEIOCYTES 1 (DTM1), which controls the early stages of that development. This gene encodes for an endoplasmic reticulum (ER) membrane protein that is present only in cereals. Our T-DNA insertion mutations gave rise to abnormal tapetal formation. Cellular organelles, especially the ER, were underdeveloped, which led to hampered differentiation and degeneration of the tapetum. In addition, the development of pollen mother cells was arrested at the early stages of meiotic prophase I. RNA in-situ hybridization analyses showed that DTM1 transcripts were most abundant in tapetal cells at stages 6 and 7, and moderately in the pollen mother cells and meiocytes. Transcripts of UDT1, which functions in tapetum development during early meiosis, were reduced in dtm1 anthers, as were those of PAIR1, which is involved in chromosome pairing and synapsis during meiosis. However, expression of MSP1 and MEL1, which function in anther wall specification and germ cell division, respectively, was not altered in the dtm1 mutant. Moreover, transcripts of DTM1 were reduced in msp1 mutant anthers, but not in udt1 and pair1 mutants. These results, together with their mutant phenotypes, suggest that DTM1 plays important roles in the ER membrane during early tapetum development, functioning after MSP1 and before UDT1, and also in meiocyte development, after MEL1 and before PAIR1.

Electric urban delivery trucks: energy use, greenhouse gas emissions, and cost-effectiveness.

We compare electric and diesel urban delivery trucks in terms of life-cycle energy consumption, greenhouse gas (GHG) emissions, and total cost of ownership (TCO). The relative benefits of electric trucks depend heavily on vehicle efficiency associated with drive cycle, diesel fuel price, travel demand, electric drive battery replacement and price, electricity generation and transmission efficiency, electric truck recharging infrastructure, and purchase price. For a drive cycle with frequent stops and low average speed such as the New York City Cycle (NYCC), electric trucks emit 42-61% less GHGs and consume 32-54% less energy than diesel trucks, depending upon vehicle efficiency cases. Over an array of possible conditions, the median TCO of electric trucks is 22% less than that of diesel trucks on the NYCC. For a drive cycle with less frequent stops and high average speed such as the City-Suburban Heavy Vehicle Cycle (CSHVC), electric trucks emit 19-43% less GHGs and consume 5-34% less energy, but cost 1% more than diesel counterparts. Considering current and projected U.S. regional electricity generation mixes, for the baseline case, the energy use and GHG emissions ratios of electric to diesel trucks range from 48 to 82% and 25 to 89%, respectively.