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1.
Water Res ; 253: 121261, 2024 Apr 01.
Article in English | MEDLINE | ID: mdl-38367373

ABSTRACT

Fully anoxic suspended growth treatment of domestic wastewater is rarely performed in practice at large scale. However, recent advances in membrane aerated biofilm reactor (MABR) technology can enable the "hybrid" concept that couples nitrification in the MABR with anoxic suspended growth for biological nitrogen removal. Small scale sequencing batch reactors were constructed to compare high-rate anoxic metabolization of influent carbon and biological phosphorus removal side-by-side with a conventional aerated system in a low-strength domestic wastewater (COD/TN ratio of approximately 6). Little differences existed in the oxidation of soluble readily biodegradable organic material between the two systems, but hydrolysis of particulate and colloidal organic matter in the anoxic reactor over a range of solid retention times was 60 % of the aerobic reactor. Reduced hydrolysis limited the amount of carbon available to ferment to volatile fatty acid (VFA), adversely impacting anoxic biological phosphorus removal (bio-P) process rates, and ortho-P removal performance was diminished by more than half at equivalent SRTs. At optimal growth conditions, i.e., an SRT of approximately 8 days and with supplementary VFA, ortho-P removal from the influent averaged roughly 75 %. Experimentation with supplemented acetic acid showed reduced anoxic metabolic efficiency, quantified via a P/O ratio of 0.90 versus 1.7 for the aerobic system, although overall anoxic bio-P removal demonstrably increased with external carbon.


Subject(s)
Phosphorus , Wastewater , Phosphorus/metabolism , Waste Disposal, Fluid , Nitrification , Carbon , Bioreactors , Nitrogen/metabolism , Denitrification
2.
AJNR Am J Neuroradiol ; 43(10): 1437-1444, 2022 10.
Article in English | MEDLINE | ID: mdl-36137654

ABSTRACT

BACKGROUND AND PURPOSE: MCA aneurysms are still commonly clipped surgically despite the recent development of a number of endovascular tools and techniques. We measured clinical uncertainty by studying the reliability of decisions made for patients with middle cerebral artery (MCA) aneurysms. MATERIALS AND METHODS: A portfolio of 60 MCA aneurysms was presented to surgical and endovascular specialists who were asked whether they considered surgery or endovascular treatment to be an option, whether they would consider recruitment of the patient in a randomized trial, and whether they would provide their final management recommendation. Agreement was studied using κ statistics. Intrarater reliability was assessed with the same, permuted portfolio of cases of MCA aneurysm sent to the same specialists 1 month later. RESULTS: Surgical management was the preferred option for neurosurgeons (n = 844/1320; [64%] responses/22 raters), while endovascular treatment was more commonly chosen by interventional neuroradiologists (1149/1500 [76.6%] responses/25 raters). Interrater agreement was only "slight" for all cases and all judges (κ = 0.094; 95% CI, 0.068-0.130). Agreement was no better within specialties or with more experience. On delayed requestioning, 11 of 35 raters (31%) disagreed with themselves on at least 20% of cases. Surgical management and endovascular treatment were always judged to be a treatment option, for all patients. Trial participation was offered to patients 65% of the time. CONCLUSIONS: Individual clinicians did not agree regarding the best management of patients with MCA aneurysms. A randomized trial comparing endovascular with surgical management of patients with MCA aneurysms is in order.


Subject(s)
Embolization, Therapeutic , Endovascular Procedures , Intracranial Aneurysm , Humans , Clinical Decision-Making , Reproducibility of Results , Uncertainty , Intracranial Aneurysm/diagnostic imaging , Intracranial Aneurysm/surgery , Neurosurgical Procedures/methods , Treatment Outcome , Retrospective Studies
3.
AJNR Am J Neuroradiol ; 42(3): 501-507, 2021 03.
Article in English | MEDLINE | ID: mdl-33509923

ABSTRACT

BACKGROUND AND PURPOSE: Conventional angiography is the benchmark examination to diagnose cerebral vasospasm, but there is limited evidence regarding its reliability. Our goals were the following: 1) to systematically review the literature on the reliability of the diagnosis of cerebral vasospasm using conventional angiography, and 2) to perform an agreement study among clinicians who perform endovascular treatment. MATERIALS AND METHODS: Articles reporting a classification system on the degree of cerebral vasospasm on conventional angiography were systematically searched, and agreement studies were identified. We assembled a portfolio of 221 cases of patients with subarachnoid hemorrhage and asked 17 raters with different backgrounds (radiology, neurosurgery, or neurology) and experience (junior ≤10 and senior >10 years) to independently evaluate cerebral vasospasm in 7 vessel segments using a 3-point scale and to evaluate, for each case, whether findings would justify endovascular treatment. Nine raters took part in the intraobserver reliability study. RESULTS: The systematic review showed a very heterogeneous literature, with 140 studies using 60 different nomenclatures and 21 different thresholds to define cerebral vasospasm, and 5 interobserver studies reporting a wide range of reliability (κ = 0.14-0.87). In our study, only senior raters reached substantial agreement (κ ≥ 0.6) on vasospasm of the supraclinoid ICA, M1, and basilar segments and only when assessments were dichotomized (presence or absence of ≥50% narrowing). Agreement on whether to proceed with endovascular management of vasospasm was only fair (κ ≤ 0.4). CONCLUSIONS: Research on cerebral vasospasm would benefit from standardization of definitions and thresholds. Dichotomized decisions by experienced readers are required for the reliable angiographic diagnosis of cerebral vasospasm.


Subject(s)
Cerebral Angiography/methods , Vasospasm, Intracranial/diagnostic imaging , Adolescent , Adult , Aged , Catheters , Female , Humans , Male , Middle Aged , Observer Variation , Reproducibility of Results , Subarachnoid Hemorrhage/complications , Vasospasm, Intracranial/etiology , Young Adult
4.
Water Sci Technol ; 82(3): 524-536, 2020 Aug.
Article in English | MEDLINE | ID: mdl-32960797

ABSTRACT

The membrane bioreactor (MBR) at the Traverse City Regional Wastewater Treatment Plant has experienced sudden and unpredictable periods of substantial permeability decline since 2011. Early observations detected irregularly-shaped Gram-positive bacteria that correlated with plant upsets. Use of biomolecular techniques, such as DNA sequencing of laboratory isolates and the mixed liquor microbial community, and fluorescent in situ hybridization, identified the dispersed organisms as members of the genus Staphylococcus. However, Staphylococcus species were consistently present during normal operation and therefore were more likely to be an indicator of the upset, not the cause. The results suggest that these microorganisms are responding to specific influent wastewater constituents. We chemically analysed seven mixed liquor samples from periods of permeability decline in 2017 and 2018, and four samples from a period of normal operation. During upset conditions, the total carbohydrate content exceeded that of normal operation by 40%. Additionally, mixed liquor calcium concentrations were 65% above normal during the upset in 2017. It is hypothesized and supported through multivariate statistical analysis and estimation of specific resistance to filtration values that a calcium-intermediated polymer bridging mechanism with extracellular polymeric substance constituents is a major contributor to fouling and permeability disruptions in the Traverse City MBR.


Subject(s)
Extracellular Polymeric Substance Matrix , Sewage , Bioreactors , Cities , In Situ Hybridization, Fluorescence , Membranes, Artificial , Wastewater
5.
Sci Data ; 7(1): 78, 2020 03 04.
Article in English | MEDLINE | ID: mdl-32132545

ABSTRACT

A challenge for data sharing in systems neuroscience is the multitude of different data formats used. Neurodata Without Borders: Neurophysiology 2.0 (NWB:N) has emerged as a standardized data format for the storage of cellular-level data together with meta-data, stimulus information, and behavior. A key next step to facilitate NWB:N adoption is to provide easy to use processing pipelines to import/export data from/to NWB:N. Here, we present a NWB-formatted dataset of 1863 single neurons recorded from the medial temporal lobes of 59 human subjects undergoing intracranial monitoring while they performed a recognition memory task. We provide code to analyze and export/import stimuli, behavior, and electrophysiological recordings to/from NWB in both MATLAB and Python. The data files are NWB:N compliant, which affords interoperability between programming languages and operating systems. This combined data and code release is a case study for how to utilize NWB:N for human single-neuron recordings and enables easy re-use of this hard-to-obtain data for both teaching and research on the mechanisms of human memory.


Subject(s)
Information Dissemination , Information Storage and Retrieval/standards , Memory , Neurons/physiology , Electrophysiological Phenomena , Humans , Software , Temporal Lobe/cytology
6.
Osteoarthritis Cartilage ; 27(8): 1174-1184, 2019 08.
Article in English | MEDLINE | ID: mdl-31028882

ABSTRACT

OBJECTIVE: Osteoarthritis (OA) is a multifactorial disease with etiological heterogeneity. The objective of this study was to classify OA subgroups by generating metabolomic phenotypes from human synovial fluid. DESIGN: Post mortem synovial fluids (n = 75) were analyzed by high performance-liquid chromatography mass spectrometry (LC-MS) to measure changes in the global metabolome. Comparisons of healthy (grade 0), early OA (grades I-II), and late OA (grades III-IV) donor populations were considered to reveal phenotypes throughout disease progression. RESULTS: Global metabolomic profiles in synovial fluid were distinct between healthy, early OA, and late OA donors. Pathways differentially activated among these groups included structural deterioration, glycerophospholipid metabolism, inflammation, central energy metabolism, oxidative stress, and vitamin metabolism. Within disease states (early and late OA), subgroups of donors revealed distinct phenotypes. Synovial fluid metabolomic phenotypes exhibited increased inflammation (early and late OA), oxidative stress (late OA), or structural deterioration (early and late OA) in the synovial fluid. CONCLUSION: These results revealed distinct metabolic phenotypes in human synovial fluid, provide insight into pathogenesis, represent novel biomarkers, and can move toward developing personalized interventions for subgroups of OA patients.


Subject(s)
Cartilage, Articular/metabolism , Metabolomics , Osteoarthritis, Knee/metabolism , Synovial Fluid/metabolism , Adult , Aged , Biomarkers/metabolism , Chromatography, Liquid , Disease Progression , Down-Regulation , Humans , Inflammation/metabolism , Mass Spectrometry , Middle Aged , Osteoarthritis, Knee/classification , Oxidative Stress , Phenotype , Severity of Illness Index , Up-Regulation , Young Adult
7.
Osteoarthritis Cartilage ; 27(3): 504-512, 2019 03.
Article in English | MEDLINE | ID: mdl-30572121

ABSTRACT

OBJECTIVE: Although joint injury itself damages joint tissues, a substantial amount of secondary damage is mediated by the cellular responses to the injury. Cellular responses include the production and activation of proteases (MMPs, ADAMTSs, Cathepsins), and the production of inflammatory cytokines. The trajectory of cellular responses is driven by the transcriptional activation of early response genes, which requires Cdk9-dependent RNA Polymerase II phosphorylation. Our objective was to determine whether inhibition of cdk9-dependent early response gene activation affects changes in the joint metabolome. DESIGN: To model post-traumatic osteoarthritis, we subjected mice to non-invasive Anterior Cruciate Ligament (ACL)-rupture joint injury. Following injury, mice were treated with flavopiridol - a potent and selective inhibitor of Cdk9 kinase activity - to inhibit Cdk9-dependent transcriptional activation, or vehicle control. Global joint metabolomics were analyzed 1 h after injury. RESULTS: We found that injury induced metabolomic changes, including increases in Vitamin D3 metabolism, anandamide, and others. Inhibition of primary response gene activation immediately after injury largely prevented the global changes in the metabolomics profiles. Cluster analysis of joint metabolomes identified groups of injury-induced and drug-responsive metabolites. CONCLUSIONS: Metabolomic profiling provides an instantaneous snapshot of biochemical activity representing cellular responses. We identified two sets of metabolites that change acutely after joint injury: those that require transcription of primary response genes, and those that do not. These data demonstrate the potential for inhibition of early response genes to alter the trajectory of cell-mediated degenerative changes following joint injury, which may offer novel targets for cell-mediated secondary joint damage.


Subject(s)
Joints/injuries , Osteoarthritis/metabolism , Animals , Anterior Cruciate Ligament Injuries/metabolism , Cyclin-Dependent Kinase 9/antagonists & inhibitors , Flavonoids/pharmacology , Joints/metabolism , Male , Metabolomics , Mice , Mice, Inbred C57BL , Osteoarthritis/etiology , Piperidines/pharmacology , Transcriptome
8.
Lupus ; 27(10): 1723-1728, 2018 Sep.
Article in English | MEDLINE | ID: mdl-29673280

ABSTRACT

Background While thrombopoeitin (TPO) agonists that act to simulate platelet production have been approved for use in steroid-refractory chronic immune thrombocytopenia purpura (ITP), there are few data on the safety and efficacy of these medications in patients with concurrent systemic lupus erythematosus (SLE) or antiphospholipid syndrome (APS). Given that these agents can increase all hematopoietic cell lineages, it is unclear if there is an increased risk for exacerbation of the underlying lymphocyte-driven autoimmune disease in this population. Case summaries This case series includes four patients with SLE, one with concurrent APS, who were treated for steroid-refractory ITP with TPO mimetics at the University of Virginia between 2005 and 2015. In three of the four cases the medication was successful in improving platelet counts and preventing bleeding events. In addition, none of the patients experienced thrombosis or worsening of their underlying autoimmune disease. Conclusions This case series suggests that TPO mimetics are safe and moderately effective in patients with ITP in the setting of SLE or APS and do not contribute to increased disease activity.


Subject(s)
Antiphospholipid Syndrome/immunology , Benzoates/therapeutic use , Blood Platelets/drug effects , Hydrazines/therapeutic use , Lupus Erythematosus, Systemic/immunology , Purpura, Thrombocytopenic, Idiopathic/drug therapy , Pyrazoles/therapeutic use , Receptors, Fc/therapeutic use , Recombinant Fusion Proteins/therapeutic use , Thrombopoietin/therapeutic use , Antiphospholipid Syndrome/blood , Antiphospholipid Syndrome/diagnosis , Autoimmunity/drug effects , Benzoates/adverse effects , Blood Platelets/immunology , Blood Platelets/metabolism , Female , Hemorrhage/chemically induced , Humans , Hydrazines/adverse effects , Lupus Erythematosus, Systemic/blood , Lupus Erythematosus, Systemic/diagnosis , Middle Aged , Molecular Mimicry , Purpura, Thrombocytopenic, Idiopathic/blood , Purpura, Thrombocytopenic, Idiopathic/diagnosis , Purpura, Thrombocytopenic, Idiopathic/immunology , Pyrazoles/adverse effects , Receptors, Thrombin/agonists , Recombinant Fusion Proteins/adverse effects , Retrospective Studies , Risk Factors , Thrombopoietin/adverse effects , Treatment Outcome , Virginia , Young Adult
9.
J Eur Acad Dermatol Venereol ; 32(8): 1352-1359, 2018 Aug.
Article in English | MEDLINE | ID: mdl-29524269

ABSTRACT

BACKGROUND: Panniculitis occurring in dermatomyositis is uncommon, with only a few cases described in the literature, most of them as case reports. OBJECTIVE: This report describes the clinicopathological and immunohistochemical findings in a series of 18 patients with panniculitis associated with dermatomyositis. METHODS: In each patient, we collected the clinical data of the cutaneous lesions as well as the characteristic clinical and laboratory findings. A series of histopathologic findings was recorded in the biopsy of each patient. A panel of antibodies was used in some cases to investigate the immunophenotype of the infiltrate. Data of treatment and follow-up were also collected. RESULTS: Of the 18 patients, 13 were female and 5 were male, ranging in age from 13 to 74 years (median, 46.4 years). In addition to panniculitis, all patients presented pathognomonic cutaneous findings of DM and reported proximal muscle weakness prior to the diagnosis of panniculitis. Muscle biopsy was performed in 17 patients and MRI in one, all with the diagnosis of inflammatory myopathy. None of the patients presented any associated neoplasia. Panniculitis lesions were located in the upper or lower limbs. Histopathology showed a mostly lobular panniculitis with lymphocytes as the main component of the infiltrate. Most cases showed also numerous plasma cells and lymphocytes surrounding necrotic adipocytes (rimming) were frequently seen. Lymphocytic vasculitis and abundant mucin interstitially deposited between collagen bundles of the dermis were also frequent findings. Late-stage lesions showed hyaline necrosis of the fat lobule and calcification. Immunohistochemistry demonstrated that most lymphocytes of the infiltrate were T-helper lymphocytes, with some B lymphocytes in the lymphoid aggregates and small clusters of CD-123-positive plasmacytoid dendritic cells in the involved fat lobule. CONCLUSION: Panniculitis in dermatomyositis is rare. Histopathologic findings of panniculitis dermatomyositis are identical to those of lupus panniculitis. Therefore, the final diagnosis requires clinic-pathologic correlation.


Subject(s)
Dermatomyositis/metabolism , Dermatomyositis/pathology , Panniculitis/metabolism , Panniculitis/pathology , Adolescent , Adult , Aged , B-Lymphocytes/pathology , Biopsy , Dendritic Cells/metabolism , Dendritic Cells/pathology , Dermatomyositis/complications , Female , Humans , Interleukin-3 Receptor alpha Subunit/metabolism , Male , Middle Aged , Muscle, Skeletal/pathology , Panniculitis/complications , T-Lymphocytes, Helper-Inducer/pathology , Young Adult
10.
Vet Comp Oncol ; 16(2): 253-261, 2018 Jun.
Article in English | MEDLINE | ID: mdl-29235249

ABSTRACT

Hemangiosarcoma (HSA) is a highly malignant tumour with aggressive biological behaviour. HSAs are more common in dogs than other domestic animals. The median survival time of dogs with HSA remains short, even with chemotherapy and surgery. Therefore, there is a critical need to improve the adjuvant chemotherapeutic regimens to improve clinical outcomes in dogs with HSA. Resveratrol has been shown to possess strong anti-proliferative and/or pro-apoptotic properties in human cancer cell lines. Nevertheless, the potential anticancer effects of resveratrol have not been reported in canine HSAs. The objective of this study is to determine the growth inhibitory effects of resveratrol in HSA cells when used alone or in combination with doxorubicin, a commonly used chemotherapeutic agent. Frog and DD-1 canine HSA cell lines were treated with varying concentrations of resveratrol with and without doxorubicin. Cell viability was measured by the MTT assay. The expression of apoptotic proteins, activation of p38 mitogen-activated protein kinase (MAPK), AMP-activated protein kinase (AMPK) and extracellular signal-regulated kinase 1/2 (ERK1/2) were assessed by western blotting. Similar to human cancer cell lines, resveratrol markedly inhibited the growth and induced apoptosis in both HSA cell lines. Mechanistically, resveratrol activated p38 MAPK, but did not affect the AMPK or the ERK1/2 pathways. Additional experiments showed that resveratrol augmented the growth-inhibitory and apoptotic effects of doxorubicin in both HSA cell lines. These findings suggest that resveratrol has pro-apoptotic effects in canine HSA cells; therefore, its use as a potential adjunct therapy in canine HSA patients warrants further investigation.


Subject(s)
Antineoplastic Agents, Phytogenic/pharmacology , Dog Diseases/drug therapy , Hemangiosarcoma/veterinary , Stilbenes/pharmacology , Analysis of Variance , Animals , Antibiotics, Antineoplastic , Antineoplastic Combined Chemotherapy Protocols/pharmacology , Anura , Apoptosis/drug effects , Cell Line, Tumor/drug effects , Dog Diseases/pathology , Dogs , Doxorubicin/pharmacology , Hemangiosarcoma/drug therapy , Hemangiosarcoma/pathology , Resveratrol
11.
Materials (Basel) ; 10(7)2017 Jul 12.
Article in English | MEDLINE | ID: mdl-28773150

ABSTRACT

The effects of alkaline copper quaternary (ACQ) and zinc borate (ZB) on the resistance of corn stalk fiber (CSF)-reinforced high-density polyethylene (HDPE) composites to biodegradation were examined. Both biocides could inhibit termites, mold fungi, and wood-decay fungi, even at high CSF formulations (i.e., 60%). Additionally, ACQ enhanced the resistance of the composite materials to certain biotic stresses better than ZB. The CSF/HDPE composites treated with ACQ at the 3.0% level exhibited a superior performance against termites, white rot fungi, and brown rot fungi. ACQ treatment at the 1% level was optimal for inhibiting soft rot fungi. Furthermore, mold growth was not observed on ACQ-treated CSF/HDPE samples. The untreated CSF/HDPE composites were more susceptible to mold infections and decay than the untreated poplar/HDPE composites, likely because of an incomplete removal of the pith. The chemical features of the corn stalk may also have influenced these differences, but this possibility will need to be explored in future investigations. Furthermore, the CSF component of CSF/HDPE composites is highly susceptible to fungal attacks, with the soft rot fungus inducing the largest mass losses, followed by the white rot fungus, and then the brown rot fungus.

12.
J Fish Biol ; 90(2): 505-527, 2017 Feb.
Article in English | MEDLINE | ID: mdl-27704556

ABSTRACT

Otolith chemistry is an effective technique for evaluating fish environmental history, but its utility in fisheries management has not been comprehensively examined. Thus, a review of otolith chemistry with emphasis on management applicability is presented. More than 1500 otolith chemistry manuscripts published from 1967 to 2015 are reviewed and descriptive case studies are used to illustrate the utility of otolith chemistry as a fisheries management tool. Otolith chemistry publications span a wide variety of topics (e.g. natal origins, habitat use, movement, stock discrimination and statistical theory) and species in freshwater and marine systems. Despite the broad distribution of manuscripts in a variety of fisheries, environmental and ecological journals, the majority of publications (83%, n = 1264) do not describe implications or applications of otolith chemistry for fisheries management. This information gap is addressed through case studies that illustrate management applications of otolith chemistry. Case studies cover numerous topics (e.g. natal origins, population connectivity, stock enhancement, transgenerational marking, pollution exposure history and invasive species management) in freshwater and marine systems using sport fishes, invasive fishes, endangered fishes and species of commercial and aquaculture importance. Otolith chemistry has diverse implications and applications for fisheries management worldwide. Collaboration among fisheries professionals from academia, government agencies and non-governmental organizations will help bridge the research-management divide and establish otolith chemistry as a fisheries management tool.


Subject(s)
Conservation of Natural Resources/methods , Fisheries , Otolithic Membrane/chemistry , Animals , Ecosystem , Fishes , Fresh Water , Introduced Species , Recreation
13.
Science ; 349(6244): aaa4019, 2015 Jul 10.
Article in English | MEDLINE | ID: mdl-26160951

ABSTRACT

Interdisciplinary studies of geologic archives have ushered in a new era of deciphering magnitudes, rates, and sources of sea-level rise from polar ice-sheet loss during past warm periods. Accounting for glacial isostatic processes helps to reconcile spatial variability in peak sea level during marine isotope stages 5e and 11, when the global mean reached 6 to 9 meters and 6 to 13 meters higher than present, respectively. Dynamic topography introduces large uncertainties on longer time scales, precluding robust sea-level estimates for intervals such as the Pliocene. Present climate is warming to a level associated with significant polar ice-sheet loss in the past. Here, we outline advances and challenges involved in constraining ice-sheet sensitivity to climate change with use of paleo-sea level records.

15.
Epidemiol Infect ; 143(8): 1702-9, 2015 Jun.
Article in English | MEDLINE | ID: mdl-25268811

ABSTRACT

Two related outbreaks (in 2009 and 2012) of cryptosporidiosis in Norwegian schoolchildren during a stay at a remote holiday farm provided us with a natural experiment to investigate possible secondary transmission of Cryptosporidium parvum IIa A19G1R1. After the children had returned home, clinical data and stool samples were obtained from their household contacts. Samples were investigated for the presence of Cryptosporidium oocysts by immunofluorescence antibody test. We found both asymptomatic and symptomatic infections, which are likely to have been secondary transmission. Laboratory-confirmed transmission rate was 17% [4/23, 95% confidence interval (CI) 7·0-37·1] in the 2009 outbreak, and 0% (95% CI 0-16·8) in the 2012 outbreak. Using a clinical definition, the probable secondary transmission rate in the 2012 outbreak was 8% (7/83, 95% CI 4·1-16·4). These findings highlight the importance of hygienic and public health measures during outbreaks or individual cases of cryptosporidiosis. We discuss our findings in light of previous studies reporting varying secondary transmission rates of Cryptosporidium spp.


Subject(s)
Asymptomatic Infections , Cryptosporidiosis/transmission , Cryptosporidium parvum/genetics , Disease Outbreaks , Feces/parasitology , Protozoan Proteins/genetics , Adolescent , Child , Cryptosporidiosis/epidemiology , Female , Fluorescent Antibody Technique , Humans , Male , Norway/epidemiology
16.
Rev Sci Instrum ; 85(11): 11E609, 2014 Nov.
Article in English | MEDLINE | ID: mdl-25430355

ABSTRACT

Sandia's Z Machine uses its high current to magnetically implode targets relevant to inertial confinement fusion. Since target performance is highly dependent on the applied drive field, measuring magnetic field at the target is essential for accurate simulations. Recently, the magnetic field at the target was measured through splitting of the sodium 3s-3p doublet at 5890 and 5896 Å. Spectroscopic dopants were applied to the exterior of the target, and spectral lines were observed in absorption. Magnetic fields in excess of 200 T were measured, corresponding to drive currents of approximately 5 MA early in the pulse.

19.
J Anim Sci ; 91(5): 2395-404, 2013 May.
Article in English | MEDLINE | ID: mdl-23463564

ABSTRACT

Antibiotics are used in ethanol production to control bacteria from competing with yeast for nutrients during starch fermentation. However, there is no published scientific information on whether antibiotic residues are present in distillers grains (DG), co-products from ethanol production, or whether they retain their biological activity. Therefore, the objectives of this study were to quantify concentrations of various antibiotic residues in DG and determine whether residues were biologically active. Twenty distillers wet grains and 20 distillers dried grains samples were collected quarterly from 9 states and 43 ethanol plants in the United States. Samples were analyzed for DM, CP, NDF, crude fat, S, P, and pH to describe the nutritional characteristics of the samples evaluated. Samples were also analyzed for the presence of erythromycin, penicillin G, tetracycline, tylosin, and virginiamycin M1, using liquid chromatography and mass spectrometry. Additionally, virginiamycin residues were determined, using a U.S. Food and Drug Administration-approved bioassay method. Samples were extracted and further analyzed for biological activity by exposing the sample extracts to 10(4) to 10(7) CFU/mL concentrations of sentinel bacterial strains Escherichia coli ATCC 8739 and Listeria monocytogenes ATCC 19115. Extracts that inhibited bacterial growth were considered to have biological activity. Physiochemical characteristics varied among samples but were consistent with previous findings. Thirteen percent of all samples contained low (≤1.12 mg/kg) antibiotic concentrations. Only 1 sample extract inhibited growth of Escherichia coli at 10(4) CFU/mL, but this sample contained no detectable concentrations of antibiotic residues. No extracts inhibited Listeria monocytogenes growth. These data indicate that the likelihood of detectable concentrations of antibiotic residues in DG is low; and if detected, they are found in very low concentrations. The inhibition in only 1 DG sample by sentinel bacteria suggests that antibiotic residues in DG were inactivated during the production process or are present in sublethal concentrations.


Subject(s)
Animal Feed/analysis , Anti-Bacterial Agents/pharmacology , Edible Grain/chemistry , Anti-Bacterial Agents/analysis , Chromatography, Liquid/veterinary , Colony Count, Microbial/veterinary , Escherichia coli/drug effects , Listeria monocytogenes/drug effects , Mass Spectrometry/veterinary , Minnesota
20.
Phys Rev E Stat Nonlin Soft Matter Phys ; 85(2 Pt 2): 026320, 2012 Feb.
Article in English | MEDLINE | ID: mdl-22463330

ABSTRACT

We present a modeling approach that enables numerical simulations of a boiling Van der Waals fluid based on the diffuse interface description. A boundary condition is implemented that allows in and out flux of mass at constant external pressure. In addition, a boundary condition for controlled wetting properties of the boiling surface is also proposed. We present isothermal verification cases for each element of our modeling approach. By using these two boundary conditions we are able to numerically access a system that contains the essential physics of the boiling process at microscopic scales. Evolution of bubbles under film boiling and nucleate boiling conditions are observed by varying boiling surface wettability. We observe flow patters around the three-phase contact line where the phase change is greatest. For a hydrophilic boiling surface, a complex flow pattern consistent with vapor recoil theory is observed.

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