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PURPOSE: The effect of different types of lipid emulsion may guide therapy of patients with intestinal failure (IF) to limit morbidity such as intestinal failure-associated liver disease (IFALD). METHODS: A retrospective chart review of pediatric patients with IF who received soybean oil lipid emulsion (SL) or mixed oil lipid emulsion (ML) was performed. Data over 1 year were collected. RESULTS: Forty-five patients received SL and 34 received ML. There were no differences in the incidence (82 versus 74%, P = 0.35) or resolution (86 versus 92%, P = 0.5) of IFALD between the cohorts. The median dose of ML was higher compared to SL (2 versus 1 g/kg/day, P < 0.001). If resolved, IFALD resolved rapidly in the ML cohort compared to the SL cohort (67 versus 37 days, P = 0.01). Weight gain was higher in the ML compared to the SL cohort at resolution of IFALD or 1 year from diagnosis of IF (P = 0.009). CONCLUSION: The administration of ML did not alter the incidence or resolution of IFALD compared to SL in pediatric IF. There was rapid resolution of IFALD and enhanced weight gain in the ML cohort compared to SL in pediatric IF.
Subject(s)
Intestinal Diseases , Intestinal Failure , Liver Diseases , Liver Failure , Humans , Child , Fat Emulsions, Intravenous/therapeutic use , Parenteral Nutrition , Retrospective Studies , Intestinal Diseases/drug therapy , Liver Diseases/complications , Liver Failure/complications , Soybean Oil/therapeutic use , Weight Gain , Fish OilsABSTRACT
Methane emissions from solid waste may represent a substantial fraction of the global anthropogenic budget, but few comprehensive studies exist to assess inventory assumptions. We quantified emissions at hundreds of large landfills across 18 states in the United States between 2016 and 2022 using airborne imaging spectrometers. Spanning 20% of open United States landfills, this represents the most systematic measurement-based study of methane point sources of the waste sector. We detected significant point source emissions at a majority (52%) of these sites, many with emissions persisting over multiple revisits (weeks to years). We compared these against independent contemporaneous in situ airborne observations at 15 landfills and established good agreement. Our findings indicate a need for long-term, synoptic-scale monitoring of landfill emissions in the context of climate change mitigation policy.
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Carbon dioxide and methane emissions are the two primary anthropogenic climate-forcing agents and an important source of uncertainty in the global carbon budget. Uncertainties are further magnified when emissions occur at fine spatial scales (<1 km), making attribution challenging. We present the first observations from NASA's Earth Surface Mineral Dust Source Investigation (EMIT) imaging spectrometer showing quantification and attribution of fine-scale methane (0.3 to 73 tonnes CH4 hour-1) and carbon dioxide sources (1571 to 3511 tonnes CO2 hour-1) spanning the oil and gas, waste, and energy sectors. For selected countries observed during the first 30 days of EMIT operations, methane emissions varied at a regional scale, with the largest total emissions observed for Turkmenistan (731 ± 148 tonnes CH4 hour-1). These results highlight the contributions of current and planned point source imagers in closing global carbon budgets.
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BACKGROUND: Hypoglycemia in neonates is common and contributes to 4.0-5.8% of neonatal intensive care unit (NICU) admissions. In utero nicotine exposure is underexplored as a potential contributor to neonatal hypoglycemia. Rat models have shown that in utero nicotine exposure can be associated with a reduction in pancreatic beta cell mass, leading to glucose dysregulation. The primary aim of this work is to study the risk of developing hypoglycemia after birth in a population of in utero nicotine-exposed neonates. METHODS: We conducted a retrospective matched cohort study that augmented an existing dataset of neonates admitted to a level IV NICU with household-based in utero nicotine exposure (Nâ=â335). Neonates in the control group parents denied household smoking (Nâ=â325), were born within a 6-month timeframe, and were within a birthweight of 50 grams of a nicotine-exposed neonate. Data reviewed included gestational age, growth parameters, maternal history of diabetes, and glucose levels within the first three hours of life per unit protocol. RESULTS: 660 neonates were included in the analysis. In utero nicotine exposure demonstrated a 94.3% posterior probability (PP) for greater hypoglycemia risk (RRâ=â1.185, 95% CrIâ=â[0.953, 1.445]). A 94.6% PP was demonstrated when neonates who were small for gestational age, intrauterine growth-restricted, and born to diabetic mothers were excluded (nâ=â482; RRâ=â1.271, 95% CrIâ=â[0.946, 1.669]). CONCLUSION: Nicotine exposure in utero was found to be a potential risk factor for developing hypoglycemia after birth. Mechanisms of action should be explored, and additional research on in utero nicotine exposure risks should follow.
Subject(s)
Hypoglycemia , Infant, Newborn, Diseases , Infant, Newborn , Female , Humans , Rats , Animals , Nicotine/adverse effects , Retrospective Studies , Cohort Studies , Hypoglycemia/chemically induced , Infant, Newborn, Diseases/epidemiology , Fetal Growth Retardation , GlucoseABSTRACT
The settling velocity of a particle is an integral parameter in stormwater modeling and design. The settling velocity can be used to predict the fate and transport of stormwater particles and if the particles contribute to nutrient loading in a watershed. Prediction of settling velocity for inorganic particles is generally well-researched and well-understood. Organic particles tend to vary widely in their physical properties and there are currently no set standards or empirical equations for estimating the settling velocity of organic particles. This paper presents data from tree leaves and seeds settling velocity experiments to better understand how organic particles settle in the context of settling velocity equations such as the one developed by Ferguson and Church. Analysis of the collected data showed that the second of the two drag coefficients (C2) used in the Ferguson and Church Equation was sensitive to particle type and shape. By averaging C2 by particle type and species, there was a correlation between the observed settling velocity and the settling velocity predicted by the Ferguson and Church Equation (R2 = 0.83). With these results, stormwater modelers and designers are equipped with a better understanding of how to represent common organic particles in terms of settling velocity. Additional research on a wider variety of organic particle types and species would expand on the dataset presented here.
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Prenylated isoflavonoids are phytochemicals with promising antifungal properties. Recently, it was shown that glabridin and wighteone disrupted the plasma membrane (PM) of the food spoilage yeast Zygosaccharomyces parabailii in distinct ways, which led us to investigate further their modes of action (MoA). Transcriptomic profiling with Z. parabailii showed that genes encoding transmembrane ATPase transporters, including Yor1, and genes homologous to the pleiotropic drug resistance (PDR) subfamily in Saccharomyces cerevisiae were upregulated in response to both compounds. Gene functions involved in fatty acid and lipid metabolism, proteostasis, and DNA replication processes were overrepresented among genes upregulated by glabridin and/or wighteone. Chemogenomic analysis using the genome-wide deletant collection for S. cerevisiae further suggested an important role for PM lipids and PM proteins. Deletants of gene functions involved in biosynthesis of very-long-chain fatty acids (constituents of PM sphingolipids) and ergosterol were hypersensitive to both compounds. Using lipid biosynthesis inhibitors, we corroborated roles for sphingolipids and ergosterol in prenylated isoflavonoid action. The PM ABC transporter Yor1 and Lem3-dependent flippases conferred sensitivity and resistance, respectively, to the compounds, suggesting an important role for PM phospholipid asymmetry in their MoAs. Impaired tryptophan availability, likely linked to perturbation of the PM tryptophan permease Tat2, was evident in response to glabridin. Finally, substantial evidence highlighted a role of the endoplasmic reticulum (ER) in cellular responses to wighteone, including gene functions associated with ER membrane stress or with phospholipid biosynthesis, the primary lipid of the ER membrane. IMPORTANCE Preservatives, such as sorbic acid and benzoic acid, inhibit the growth of undesirable yeast and molds in foods. Unfortunately, preservative tolerance and resistance in food spoilage yeast, such as Zygosaccharomyces parabailii, is a growing challenge in the food industry, which can compromise food safety and increase food waste. Prenylated isoflavonoids are the main defense phytochemicals in the Fabaceae family. Glabridin and wighteone belong to this group of compounds and have shown potent antifungal activity against food spoilage yeasts. The present study demonstrated the mode of action of these compounds against food spoilage yeasts by using advanced molecular tools. Overall, the cellular actions of these two prenylated isoflavonoids share similarities (at the level of the plasma membrane) but also differences. Tryptophan import was specifically affected by glabridin, whereas endoplasmic reticulum membrane stress was specifically induced by wighteone. Understanding the mode of action of these novel antifungal agents is essential for their application in food preservation.
Subject(s)
Refuse Disposal , Saccharomyces cerevisiae Proteins , Saccharomyces cerevisiae/metabolism , Antifungal Agents/pharmacology , Antifungal Agents/metabolism , Food , Tryptophan/metabolism , Yeasts , Lipids , Membrane Transport Proteins/metabolism , Saccharomyces cerevisiae Proteins/metabolismABSTRACT
OBJECTIVE: To explore the use of an episode grouper to more accurately identify the complete set of surgical services typically provided in a surgical episode of care and the corresponding range of prices, using colectomy for cancer as the example. BACKGROUND: Price transparency is an important policy issue that will require surgeons to better understand the components and cost of care. METHODS: This study uses the Episode Grouper for Medicare business logic to construct colectomy surgical episodes of care for cancer using Medicare claims data for the Boston Hospital Referral Region from 2012 to 2015. Descriptive statistics show the mean reimbursement based on patient severity and stage of surgery, along with the number of unique clinicians billing for care and the mix of services provided. RESULTS: The Episode Grouper for Medicare episode grouper identified 3182 colectomies in Boston between 2012 and 2015, with 1607 done for cancer. The mean Medicare allowed amount per case is $29,954 and varies from $26,605 to $36,850 as you move from low to high-severity cases. The intrafacility stage is the most expensive ($23,175 on average) compared with the pre ($780) and post ($6,479) facility stages. There is tremendous heterogeneity in the service mix. CONCLUSIONS: Episode groupers are a potentially valuable tool for identifying variations in service mix and teaming patterns that correlate with a total price. By looking at patient care holistically, stakeholders can identify opportunities for price transparency and care redesign that have heretofore been hidden.
Subject(s)
Bass , Neoplasms , Surgeons , Aged , Humans , United States , Animals , Episode of Care , MedicareABSTRACT
OBJECTIVE: Lipid emulsion contributes to parenteral nutrition associated cholestasis (PNAC). For decades, soybean oil-based intravenous lipid emulsion (SO-ILE) was the predominant product. Recently, a multicomponent lipid emulsion containing soybean oil, medium-chain triglycerides, olive oil and fish oil (SMOF-ILE) has been used off-label in neonatal care. This study evaluates the incidence of PNAC in neonates who received SMOF-ILE or SO-ILE. METHODS: This was a retrospective review of neonates who received SMOF-ILE or SO-ILE for at least 14 days. Patients receiving SMOF-ILE were matched based on gestational age (GA) and birth weight to a historical cohort receiving SO-ILE. The primary outcomes were the incidences of PNAC among all patients and patients without intestinal failure. The secondary outcomes were clinical outcomes and incidence of PNAC stratified by GA. Clinical outcomes included liver function tests, growth parameters, and development of retinopathy of prematurity and intraventricular hemorrhage. RESULTS: Forty-three neonates who received SMOF-ILE were matched to 43 neonates who received SOILE. There were no significant differences in baseline characteristics. The incidence of PNAC in the total population was 12% in the SMOF-ILE cohort and 23% in the SO-ILE cohort (p = 0.26). The lipid dosage of SMOF-ILE was significantly higher at time of peak direct serum bilirubin concentration compared with SO-ILE cohort (p = 0.05). Clinically significant differences were noted in laboratory endpoints in several subgroups. CONCLUSIONS: There was no significant difference in the incidence of PNAC among neonates in a SMOFILE cohort compared with a historical SO-ILE cohort.
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BACKGROUND: The enumeration of the primary care workforce relies on potentially inaccurate specialty designations sourced from licensure registries and clinician surveys. OBJECTIVE: To use an activity-based measure of primary care to estimate the number of physicians, nurse practitioners (NPs), and physician assistants (PAs) providing primary care to Medicare beneficiaries. DESIGN: Observational study using Medicare fee-for-service (FFS) claims data. SUBJECTS: All clinicians in the US billing Medicare in 2019 and their fee-for-service Medicare patients. MAIN MEASURES: We construct three measures that together distinguish primary care from specialty clinicians: (1) presence of evaluation and management (E&M) services in a setting consistent with primary care, (2) the dispersion of clinical care across International Classification of Diseases-10 (ICD-10) chapters, and (3) the extent of provided services that are atypical of primary care (e.g., surgical procedure). We apply parameters to the measures to identify the clinicians likely providing primary care and compare the resulting classifications across provider type. KEY RESULTS: Of physicians with at least 50 Medicare beneficiaries, 19-22% provide primary care. Of medical generalists (i.e., family medicine, internal medicine) with at least 50 beneficiaries, 61-68% provide primary care. We estimate that 40-45% of NPs and 27-30% of PAs meeting the panel size threshold are primary care providers in FFS Medicare. CONCLUSIONS: Our findings suggest that based on a primary care practice style, the number of primary care physicians in FFS Medicare is likely smaller than conventional estimates. However, compared to prior estimates, the number of primary care NPs is larger and the number of PAs is similar.
Subject(s)
Medicare , Physicians , Humans , Aged , United States , Workforce , Fee-for-Service Plans , Primary Health CareABSTRACT
This study investigated item- and test-level functioning of the Structured Assessment of Violence Risk in Youth (SAVRY) and differential item functioning (DIF) across gender and race/ethnicity in justice-involved youth (JIY) using item response theory analysis. Participants were 868 JIY (23.7% female; 26.9% White, 50.9% Black, and 22.2% Hispanic) in pre-trial detention centers in Connecticut. Results obtained from the application of the graded response model showed that the SAVRY items were not equally discriminating JIY with varying levels of the latent trait, with "Poor compliance" as the most discriminating item and "History of self-harm or suicide attempts" as the least discriminating item. At the test level, the SAVRY provided precise (reliable) information about the latent trait for the majority of JIY whose latent trait between two standard deviations below and above the mean. Results of DIF revealed that six items operated inconsistently between White, Black, and Hispanic JIY, among which two items also functioned differentially across gender.
Subject(s)
Psychological Tests , Violence , Adolescent , Female , Humans , Male , Connecticut , Hispanic or Latino , White , Black or African American , Correctional FacilitiesABSTRACT
BACKGROUND: Outcomes data of intramedullary nail fixation (IMN) constructs for complex Schatzker VI tibial plateau fractures are scant in the literature. This study compares the clinical and radiographic outcomes of IMN, dual plate, and single plate constructs for Schatzker IV tibial plateau fractures. METHODS: Retrospective cohort study of sixty-two patients at a University-based Level 1 trauma center who underwent open reduction internal fixation for Schatzker VI tibial plateau fracture. Constructs evaluated were IMN (with or without raft screws), dual plating, and single plating. Demographic, clinical, and radiographic outcomes were recorded. All fractures were additionally classified based on the OTA classification for sub analyses. Mean follow-up was 13.2 (SD 13.3) months. Predictors of construct selection and outcomes were evaluated with bivariate logistic regression. Outcomes were compared between groups with independent samples t-tests and Chi Square tests. RESULTS: No significant demographic differences were found between IMN, dual plate or single plate construct cohorts. There was a higher proportion of open fractures within the IMN construct group versus the dual plate cohort (21.1% vs 3.6%). No statistically significant differences in radiographic outcomes were observed between cohort groups except for small but statistically significant differences in condylar width (CW) ratio change and tibial slope; when fracture cohorts were sub analyzed by specific OTA classification, there were no significant differences in any radiographic outcomes. There was a significant difference between the ratio of OTA 41C1, C2 and C3 fractures regarding treatment allocation (p = 0.004), favoring dual plate fixation for OTA 41C3 fractures. There were no significant differences found between treatment cohorts in terms of all cause complications (p > 0.05). IMN and single plate constructs were utilized when posteromedial condyle fractures were nondisplaced or minimally displaced. CONCLUSION: Intramedullary nail fixation with or without supplemental raft screws produced similar short-term clinical and radiographic results compared to dual and single plate constructs among patients with Schatzker VI fracture types, regardless of OTA classification. Level of Evidence Level III retrospective cohort.
Subject(s)
Tibial Fractures , Tibial Plateau Fractures , Humans , Retrospective Studies , Fracture Fixation, Internal/methods , Bone Plates , Tibial Fractures/diagnostic imaging , Tibial Fractures/surgery , Treatment OutcomeABSTRACT
Understanding, prioritizing, and mitigating methane (CH4) emissions requires quantifying CH4 budgets from facility scales to regional scales with the ability to differentiate between source sectors. We deployed a tiered observing system for multiple basins in the United States (San Joaquin Valley, Uinta, Denver-Julesburg, Permian, Marcellus). We quantify strong point source emissions (>10 kg CH4 h-1) using airborne imaging spectrometers, attribute them to sectors, and assess their intermittency with multiple revisits. We compare these point source emissions to total basin CH4 fluxes derived from inversion of Sentinel-5p satellite CH4 observations. Across basins, point sources make up on average 40% of the regional flux. We sampled some basins several times across multiple months and years and find a distinct bimodal structure to emission timescales: the total point source budget is split nearly in half by short-lasting and long-lasting emission events. With the increasing airborne and satellite observing capabilities planned for the near future, tiered observing systems will more fully quantify and attribute CH4 emissions from facility to regional scales, which is needed to effectively and efficiently reduce methane emissions.
Subject(s)
Air Pollutants , Methane , Air Pollutants/analysis , Methane/analysis , United StatesABSTRACT
Stimuli-responsive materials are exploited in biological, materials, and sensing applications. We introduce a new endogenous stimulus, biomacromolecule crowding, which we achieve by leveraging changes in thermoresponsive properties of polymers upon high concentrations of crowding agents. We prepare poly(2-oxazoline) amphiphiles that exhibit lower critical solution temperatures (LCST) in serum above physiological temperature. These amphiphiles stabilize oil-in-water nanoemulsions at temperatures below the LCST but are ineffective surfactants above the LCST, resulting in emulsion fusion. We find that the transformations observed upon heating nanoemulsions above their surfactant's LCST can instead be induced at physiological temperatures through the addition of polymers and protein, rendering thermoresponsive materials "crowding responsive." We demonstrate that the cytosol is a stimulus for nanoemulsions, with droplet fusion occurring upon injection into cells of living zebrafish embryos. This report sets the stage for classes of thermoresponsive materials to respond to macromolecule concentration rather than temperature changes.
Subject(s)
Nanostructures , Stimuli Responsive Polymers , Animals , Emulsions , Polymers , Surface-Active Agents , Temperature , Water , ZebrafishABSTRACT
Clinical implementation of online adaptive radiation therapy requires initial and ongoing performance assessment of the underlying auto-segmentation and adaptive planning algorithms, although a straightforward and efficient process for this in phantom is lacking. The purpose of this work was to investigate robustness and repeatability of the artificial intelligence-assisted online segmentation and adaptive planning process on the Varian Ethos adaptive platform, and to develop an end-to-end test strategy for online adaptive radiation therapy. Five synthetic deformations were generated and applied to a computed tomography image of an anthropomorphic pelvis phantom, and reference treatment plans were generated from each of the resulting deformed images. The undeformed phantom was repeatedly imaged, and the online adaptive process was performed including auto-segmentation, review and manual correction of contours, and adaptive plan creation. One adaptive fractions in five different deformation scenarios were performed. The manually corrected contours had a high degree of consistency (> 93% Dice similarity coefficient and < 1.0 mm mean surface distance) across repeated fractions, with no significant variation across the synthetic deformation instance except for bowel (p = 0.026, one-way ANOVA). Adaptive treatment plans also resulted in highly consistent dose-volume values for targets and organs at risk. A straightforward and efficient process was developed and used to quantify a set of organ specific contouring and dosimetric action levels to help establish uncertainty bounds for an end-to-end test on the Varian Ethos system.
Subject(s)
Radiotherapy Planning, Computer-Assisted , Radiotherapy, Intensity-Modulated , Artificial Intelligence , Humans , Organs at Risk , Radiotherapy Dosage , Radiotherapy Planning, Computer-Assisted/methods , Radiotherapy, Intensity-Modulated/methods , Reproducibility of ResultsABSTRACT
Background and Objective: Small, dense low-density lipoproteins (LDLs) are considered more atherogenic than normal size LDLs. However, the measurement of small, dense LDLs requires sophisticated laboratory methods, such as ultracentrifugation, gradient gel electrophoresis, or nuclear magnetic resonance. We aimed to analyze whether the LDL apolipoprotein B (LDLapoB)-to-LDL cholesterol (LDLC) ratio is associated with cardiovascular mortality and whether this ratio represents a biomarker for small, dense LDLs. Methods: LDLC and LDLapoB were measured (beta-quantification) and calculated (according to Friedewald and Baca, respectively) for 3291 participants of the LURIC Study, with a median (inter-quartile range) follow-up for cardiovascular mortality of 9.9 (8.7−10.7) years. An independent replication cohort included 1660 participants. Associations of the LDLapoB/LDLC ratio with LDL subclass particle concentrations (ultracentrifugation) were tested for 282 participants. Results: In the LURIC Study, the mean (standard deviation) LDLC and LDLapoB concentrations were 117 (34) and 85 (22) mg/dL, respectively; 621 cardiovascular deaths occurred. Elevated LDLapoB/LDLC (calculated and measured) ratios were significantly and independently associated with increased cardiovascular mortality in the entire cohort (fourth vs. first quartile: hazard ratio (95% confidence interval) = 2.07 (1.53−2.79)) and in statin-naïve patients. The association between calculated LDLapoB/LDLC ratio and cardiovascular mortality was replicated in an independent cohort. High LDLapoB/LDLC ratios were associated with higher LDL5 and LDL6 concentrations (both p < 0.001), but not with concentrations of larger LDLs. Conclusions: Elevated measured and calculated LDLapoB/LDLC ratios are associated with increased cardiovascular mortality. Use of LDLapoB/LDLC ratios allows estimation of the atherogenic risk conferred by small, dense LDLs.
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Background: Females of the gammaridean amphipod Ampelisca eschrichtii with signs of regenerating, previously atrophied ovaries were recovered from the northeastern shelf of Sakhalin Island (Okhotsk Sea, Russia). Ovarian regeneration was previously unknown for any amphipod species. A. eschrichtii have a predominantly 2-year life cycle (from embryo to adult death) and reproduce once between late winter or early spring at the age of 2 years. Occasionally, females survive to a third year. An adaptive value of extended survival among these females is likely to require that they are also reproductive. Methods: Histological sections from a second-year female with ovarian atrophy, a female with normal ovaries, a third-year female with ovarian regeneration, as well as testes of an immature and a sexually mature male were compared to determine the sources of cells of the germinal and somatic lines necessary for ovarian regeneration. Results: Ovarian regeneration in the third-year female began with the formation of a new germinal zone from germ cells preserved in the atrophied ovaries and eosinophilic cells of the previously starving second-year female. Eosinophilic cells form the mesodermal component of the germinal zone. A mass of these cells appeared in the second-year female that had atrophied ovaries and in large numbers on the intestine wall of the third-year female with regenerating ovaries. These eosinophilic cells appear to migrate into the regenerating ovaries. Conclusions: All germ cells of the second-year female are not lost during ovarian atrophy and can be involved in subsequent ovarian regeneration. Eosinophilic cells involved in ovarian regeneration are of mesodermal origin. The eosinophilic cell morphologies are similar to those of quiescence cells (cells in a reversible state that do not divide but retain the ability to re-enter cell division and participate in regeneration). These histological data thus indicate that eosinophilic and germ cells of third-year females can participate in the regeneration of the ovaries to reproduce a second brood. The precursors of these third-year females (a small number the second-year females with an asynchronous [summer] breeding period and ovaries that have atrophied due to seasonal starvation) appear to possess sources of somatic and germ cells that are sufficient for ovarian regeneration and that may be adaptations to starvation stress.
Subject(s)
Amphipoda , Ovary , Animals , Male , Female , Germ Cells , Reproduction , Life Cycle StagesABSTRACT
In spring 2020, the University of Minnesota Erosion and Stormwater Management Certification Program temporarily ceased in-person workshops due to the spread of COVID-19. Twenty workshops were canceled, and the 1,233 attendees (all adult learners) were moved into asynchronous online course sections. These online workshops were the first remote courses that many of the attendees had ever attempted. Here, we provide tips for successfully creating online classes for nontraditional student populations.
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Powered by renewable electricity, biological | inorganic hybrids employ water-splitting electrocatalysis and generate H2 as reducing equivalents for microbial catalysis. The approach integrates the beauty of biocatalysis with the energy efficiency of inorganic materials for sustainable chemical production. Yet a successful integration requires delicate control of the hybrid's extracellular chemical environment. Such an argument is evident in the exemplary case of O2 because biocatalysis has a stringent requirement of O2 but the electrocatalysis may inadvertently perturb the oxidative pressure of biological moieties. Here we report the addition of perfluorocarbon (PFC) nanoemulsions promote a biocompatible O2 microenvironment in a O2-sensitive N2-fixing biological | inorganic hybrid. Langmuir-type nonspecific binding between bacteria and nanoemulsions facilitates O2 transport in bacterial microenvironment and leads to a 250% increase in efficiency for organic fertilizers within 120 hours. Controlling the biological microenvironment with nanomaterials heralds a general approach accommodating the compatibility in biological | inorganic hybrids.
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Temporal variation in the density and distribution of the burrowing shrimps, Neotrypaea californiensis and Upogebia pugettensis, were compared in two estuaries along the West coast of the United States (USA) where they are recognized as important ecosystem engineers. Since these shrimp construct deep burrows in the sediment, we quantified the relationship between burrow openings and shrimp density (1.5 and 1.7 burrow openings per shrimp for N. californiensis and U. pugettensis respectively) to permit population abundance estimates to be made over broad landscape scales. Neotrypaea californiensis populations estimated from burrow counts collected using a gridded survey design across representative tide flats declined by 25% between 2008-2010 in Yaquina Bay, Oregon and by 67% in Willapa Bay, Washington from 2006-2011, but increased again in Willapa Bay by 2014. Upogebia pugettensis had mostly disappeared from Willapa Bay by 2006 and declines were observed in Yaquina Bay, but the magnitude and long-term trajectory of U. pugettensis in this estuary was less clear. These species population fluctuations mirrored those observed in density collected at discrete sampling locations over the same period, equate to large changes in secondary production, and have likely resulted in substantial changes to estuarine habitat and food webs.
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Platelet-rich plasma (PRP) has been investigated to promote wound healing in a variety of tissues. Thrombin, another essential component of wound healing, is sometimes combined with PRP to generate a fibrin clot in order to retain the sample at the delivery site and to stimulate growth factor release. Using a fully autologous approach, autologous serum (AS) with thrombin activity can be prepared using a one-step procedure by supplementing with ethanol (E+ AS) to prolong room temperature stability or prepared ethanol free (E- AS) by utilizing a two-step procedure to prolong stability. The objective of this study was to evaluate potential wound healing mechanisms of these two preparations using commercially available devices. A variety of tests were conducted to assess biocompatibility and growth factor release from PRP at various ratios. It was found that E- AS contained greater leukocyte viability in the product (97.1 ± 2.0% compared to 41.8 ± 11.5%), supported greater bone marrow mesenchymal stem cell proliferation (3.7× vs 0.8× at a 1:4 ratio and 3.6× vs 1.6× at a 1:10 ratio), and stimulated release of growth factors and cytokines from PRP to a greater extent than E+ AS. Of the 36 growth factors and cytokines evaluated, release of 27 of them were significantly reduced by the presence of ethanol in at least one of the tested configurations. It is concluded that the high concentrations of ethanol needed to stabilize point of care autologous thrombin preparations could be detrimental to normal wound healing processes.