Publications by authors named "Steven Simske"

Article Synopsis
  • Sustainable fuel initiatives, like the EPA's Renewable Fuel Standard and the Department of Energy's Sustainable Aviation Fuel Grand Challenge, have boosted the production of corn ethanol and soybean biodiesel, but localized biomass sourcing information is lacking.
  • A new dataset utilizes geospatial analysis and USDA crop census data from 2017 to provide insights into biomass sourcing, helping to bridge the knowledge gap related to biofuel costs and environmental impacts.
  • By offering detailed, county-level data, this dataset enhances techno-economic assessments and life-cycle analyses, aiding stakeholders in making better investment and resource decisions regarding first-generation biofuels in the U.S.
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Blockchain can function as a foundational technology with numerous applications in smart cities. The objective of this paper is twofold. First, it provides a detailed overview of the extant literature on blockchain applications in smart cities; second, it reveals the trends and suggests future research directions for scholars who wish to contribute to this rapidly growing field.

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Bone loss associated with microgravity exposure poses a significant barrier to long-duration spaceflight. Osteoprotegerin-Fc (OPG-Fc) is a receptor activator of nuclear factor kappa-B ligand (RANKL) inhibitor that causes sustained inhibition of bone resorption after a single subcutaneous injection. We tested the ability of OPG-Fc to preserve bone mass during 12 days of spaceflight (SF).

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Background/aim: Insulin-like growth factor-1 (IGF-1) and macrophage colony-stimulating factor (MCSF) are critical to skeletal homeostasis. We investigated the effects of combined IGF-1 plus MCSF on mice.

Materials And Methods: C57BL/6J mice, aged 7 weeks, were assigned to baseline, vehicle, IGF-1, MCSF, or combined IGF-1 plus MCSF (1 mg/kg/day each, n=12-13/group, 28-day duration).

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In this study, we examined the effects of 2-week hindlimb un-loading in mice followed by re-ambulation with voluntary access to running wheels. The recovery period was terminated at a time point when physical performance--defined by velocity, time, and distance ran per day--of the suspended group matched that of an unsuspended group. Mice were assigned to one of four groups: unsuspended non-exercise (Control), 14 days of hindlimb suspension (HS), 7 days of access to running wheels (E7), or 14 days of HS plus 7 days access to running wheels (HSE7).

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Macrophage colony-stimulating factor (M-CSF) is a hematopoietic growth factor that plays a critical role in early osteoclastogenesis. To characterize the skeletal effects of M-CSF, we administered soluble M-CSF to mice. It was hypothesized that M-CSF would stimulate bone formation through coupled activity of osteoclasts and osteoblasts.

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This letter introduces a new algorithm for the restoration of a noisy blurred image based on the support vector regression (SVR). Experiments show that the performance of the SVR is very robust in blind image deconvolution where the types of blurs, point spread function (PSF) support, and noise level are all unknown.

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Most current Holter devices monitor the ECG for 24 to 72 hours. However, for the accurate diagnosis of many cardiac diseases, especially for the wide variety of asymptomatic cases, continuous ECG monitoring for weeks or even months may be required. In this paper, we focus on the issue of ECG compression during long-term monitoring of the patient.

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The number one priority for any manned space mission is the health and safety of its crew. The study of the short and long term physiological effects on humans is paramount to ensuring crew health and mission success. One of the challenges associated in studying the physiological effects of space flight on humans, such as loss of bone and muscle mass, has been that of readily attaining the data needed to characterize the changes.

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Osteoporosis is a disease characterized by low bone mass and structural deterioration of bone tissue, leading to bone fragility and increased susceptibility to fractures. The microgravity of space creates an extreme environment that provides a model for osteoporosis in humans. This greatly accelerated form of osteopenia results in a 0.

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Macrophage-Colony Stimulating Factor (M-CSF) is critical for osteoclast differentiation and development. It has been previously observed that M-CSF administration and over-expression in mice causes an increase in cortical bone formation. We hypothesize that M-CSF increases osteoblast activity indirectly via coupling of these two bone cells.

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The objective of this study was to examine changes in the long bones of male C57BL/6J mice with growth and aging, and to consider the applicability of this animal for use in studying Type II osteoporosis. Male C57BL/6J mice were aged in our colony between 4 and 104 weeks (n=9-15/group). The right femur and humeri were measured for length and subjected to mechanical testing (3-point flexure) and compositional analysis.

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There are several aspects of the spaceflight environment that may lead to changes in immunity: mission-related psychological stress, radiation, and changes in gravity. On December 5, 2001, the space shuttle Endeavor launched for a 12-day mission to examine these effects on C57BL/6 mice for the first time. On their return, assays were performed on the spleen, blood, and bone marrow.

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This portion of the study quantified the effects of a 12-day space shuttle mission (Space Transport System-108/UF-1) on body and lymphoid organ masses, activation marker expression, cytokine secretion, and erythrocyte and thrombocyte characteristics in C57BL/6 mice. Animals in flight (Flt group) had 10-12% lower body mass compared with ground controls housed either in animal enclosure modules or under standard vivarium conditions (P < 0.001) and the smallest thymus and spleen masses.

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We investigated the effect of major histocompatibility complex class II (MHC II) knockout on the development of the mouse peripheral skeleton. These C2D mice had less skeletal development at 8, 12 and 16 weeks of age compared to wild-type C57BL/6J (B6) male mice. The C2D mice had decreased femur mechanical, geometric and compositional measurements compared to wild type mice at each of these ages.

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To determine whether the mouse loses bone with aging and whether the changes mimic those observed in human aging, we examined the changes in the tibial metaphysis and diaphysis in the male C57BL/6J mouse over its life span using microcomputed tomography (microCT). Cancellous bone volume fraction (BV/TV) decreased 60% between 6 weeks and 24 months of age. Loss was characterized by decreased trabecular number (Tb.

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Previous investigations have reported that space flight may produce a stimulating effect on microbial metabolism; however, the specific underlying mechanisms associated with the observed changes have not yet been identified. In an effort to systematically evaluate the effect of space flight on each phase of microbial growth (lag, exponential and stationary), a series of experiments was carried out using in vitro suspension cultures of Escherichia coli aboard seven US Space Shuttle missions. The results indicated that, as a result of space flight, the lag phase was shortened, the duration of exponential growth was increased, and the final cell population density was approximately doubled.

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