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Globule leukocytes and mast cells in the rat trachea: their number, distribution, and response to compound 48/80 and dexamethasone.
Globule leukocytes in the epithelium of the rat trachea may be counterparts of mucosal mast cells that are located in the gastrointestinal tract. If they are indeed similar to mucosal mast cells, globule leukocytes would be expected to decrease in number in rats treated with dexamethasone but not in rats treated with compound 48/80, an agent which causes non-antigenic degranulation of connective tissue mast cells. In this study, we determined the number and compared the distribution of globule leukocytes and connective tissue mast cells in the tracheas of pathogen-free rats. We then determined whether the number of these two types of cells changes in rats treated for 5 days with compound 48/80, dexamethasone, a combination of compound 48/80 and dexamethasone, or saline. We identified globule leukocytes and mast cells in whole mounts and histological sections of rat tracheas by using a histochemical reaction that demonstrates the chymotrypsin-like protease (chloroacetate esterase) present in mast cell granules. Using this method, we found that approximately 225,000 globule leukocytes were present in the epithelium of the trachea. These cells were most abundant in the rostral trachea. Rats treated with dexamethasone had a 91% reduction in the number of globule leukocytes with protease-containing granules, but rats treated with compound 48/80 had a normal number of these cells. We found some 55,000 connective tissue mast cells in the same tracheas. Mast cells were most abundant in the posterior membrane of the caudal trachea and in the lamina propria between cartilaginous rings. Rats treated with compound 48/80 had a 96% reduction in mast cells with protease-containing granules, but rats treated with dexamethasone had a normal complement of mast cells. We conclude that globule leukocytes are abundant in the tracheas of healthy rats, are similar in morphology and pharmacological responses to mucosal mast cells located in other organs of rats, and are more numerous than and have a different distribution than connective tissue mast cells. Globule leukocytes in the tracheal epithelium may have a role in respiratory defenses similar to that of mucosal mast cells in other organs
Role of Reversal Learning Impairment in Social Disinhibition following Severe Traumatic Brain Injury
OBJECTIVES: The current study aimed to determine whether reversal learning impairments and feedback-related negativity (FRN), reflecting reward prediction error signals generated by negative feedback during the reversal learning tasks, were associated with social disinhibition in a group of participants with traumatic brain injury (TBI). METHODS: Number of reversal errors on a social and a non-social reversal learning task and FRN were examined for 21 participants with TBI and 21 control participants matched for age. Participants with TBI were also divided into low and high disinhibition groups based on rated videotaped interviews. RESULTS: Participants with TBI made more reversal errors and produced smaller amplitude FRNs than controls. Furthermore, participants with TBI high on social disinhibition made more reversal errors on the social reversal learning task than did those low on social disinhibition. FRN amplitude was not related to disinhibition. CONCLUSIONS: These results suggest that impairment in the ability to update behavior when social reinforcement contingencies change plays a role in social disinhibition after TBI. Furthermore, the social reversal learning task used in this study may be a useful neuropsychological tool for detecting susceptibility to acquired social disinhibition following TBI. Finally, that the FRN amplitude was not associated with social disinhibition suggests that reward prediction error signals are not critical for behavioral adaptation in the social domain
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INTEGRATED SAFETY MANAGEMENT SYSTEM SAFETY CULTURE IMPROVEMENT INITIATIVE
In 2007, the Department of Energy (DOE) identified safety culture as one of their top Integrated Safety Management System (ISMS) related priorities. A team was formed to address this issue. The team identified a consensus set of safety culture principles, along with implementation practices that could be used by DOE, NNSA, and their contractors. Documented improvement tools were identified and communicated to contractors participating in a year long pilot project. After a year, lessons learned will be collected and a path forward determined. The goal of this effort was to achieve improved safety and mission performance through ISMS continuous improvement. The focus of ISMS improvement was safety culture improvement building on operating experience from similar industries such as the domestic and international commercial nuclear and chemical industry
Vacuum Stability, Perturbativity, and Scalar Singlet Dark Matter
We analyze the one-loop vacuum stability and perturbativity bounds on a
singlet extension of the Standard Model (SM) scalar sector containing a scalar
dark matter candidate. We show that the presence of the singlet-doublet quartic
interaction relaxes the vacuum stability lower bound on the SM Higgs mass as a
function of the cutoff and lowers the corresponding upper bound based on
perturbativity considerations. We also find that vacuum stability requirements
may place a lower bound on the singlet dark matter mass for given singlet
quartic self coupling, leading to restrictions on the parameter space
consistent with the observed relic density. We argue that discovery of a light
singlet scalar dark matter particle could provide indirect information on the
singlet quartic self-coupling.Comment: 25 pages, 10 figures; v2 - fixed minor typos; v3 - added to text
discussions of other references, changed coloring of figures for easier black
and white viewin
Removal of organic matter from wastewater reverse osmosis concentrate using granular activated carbon and anion exchange resin adsorbent columns in sequence.
Reverse osmosis concentrate (ROC) generated as a waste stream during reverse osmosis treatment of reclaimed wastewater, presents significant disposal challenges. This is because it causes environmental pollution when it is disposed to lands and natural water bodies. A long-term dynamic adsorption experiment was conducted by passing ROC from a wastewater reclamation plant, firstly through a granular activated carbon (GAC) column, and subsequently through an anion exchange resin (Purolite) column, for the removal of two major ROC pollutants, namely dissolved organic carbon (DOC) and microorganic pollutants (MOP). GAC removed most of the smaller-sized low molecular weight neutrals and building block fractions as well as the hydrophobic fraction of DOC with much less removal by the subsequent Purolite column. In contrast, the humics fraction was less well removed by the GAC column; however, Purolite column removed all that was remaining of this fraction. This study demonstrated that combining adsorbents having different affinities towards a variety of DOC fractions constitute an effective method of taking advantage of their different properties and achieving larger DOC removals. Almost 100% of all 17 MOPs were removed by the GAC column, even after 2880 bed volumes of continuous use. This contrasted with the DOC fractions' removal which was much lower
The metabolome as a diagnostic for maximal aerobic capacity during exercise in type 1 diabetes
\ua9 The Author(s) 2024.Aims/hypothesis: Our aim was to characterise the in-depth metabolic response to aerobic exercise and the impact of residual pancreatic beta cell function in type 1 diabetes. We also aimed to use the metabolome to distinguish individuals with type 1 diabetes with reduced maximal aerobic capacity in exercise defined by V˙O2peak. Methods: Thirty participants with type 1 diabetes (≥3 years duration) and 30 control participants were recruited. Groups did not differ in age or sex. After quantification of peak stimulated C-peptide, participants were categorised into those with undetectable (<3 pmol/l), low (3–200 pmol/l) or high (>200 pmol/l) residual beta cell function. Maximal aerobic capacity was assessed by V˙O2peak test and did not differ between control and type 1 diabetes groups. All participants completed 45 min of incline treadmill walking (60% V˙O2peak) with venous blood taken prior to exercise, immediately post exercise and after 60 min recovery. Serum was analysed using targeted metabolomics. Metabolomic data were analysed by multivariate statistics to define the metabolic phenotype of exercise in type 1 diabetes. Receiver operating characteristic (ROC) curves were used to identify circulating metabolomic markers of maximal aerobic capacity (V˙O2peak) during exercise in health and type 1 diabetes. Results: Maximal aerobic capacity (V˙O2peak) inversely correlated with HbA1c in the type 1 diabetes group (r2=0.17, p=0.024). Higher resting serum tricarboxylic acid cycle metabolites malic acid (fold change 1.4, p=0.001) and lactate (fold change 1.22, p=1.23
710−5) differentiated people with type 1 diabetes. Higher serum acylcarnitines (AC) (AC C14:1, F value=12.25, p=0.001345; AC C12, F value=11.055, p=0.0018) were unique to the metabolic response to exercise in people with type 1 diabetes. C-peptide status differentially affected metabolic responses in serum ACs during exercise (AC C18:1, leverage 0.066; squared prediction error 3.07). The malic acid/pyruvate ratio in rested serum was diagnostic for maximal aerobic capacity (V˙O2peak) in people with type 1 diabetes (ROC curve AUC 0.867 [95% CI 0.716, 0.956]). Conclusions/interpretation: The serum metabolome distinguishes high and low maximal aerobic capacity and has diagnostic potential for facilitating personalised medicine approaches to manage aerobic exercise and fitness in type 1 diabetes. Graphical Abstract: (Figure presented.)
Synthetically tuneable biomimetic artificial photosynthetic reaction centres that closely resemble the natural system in purple bacteria
© 2016 The Royal Society of Chemistry. Porphyrin-based photosynthetic reaction centre (PRC) mimics, ZnPQ-Q2HP-C60 and MP2Q-Q2HP-C60 (M = Zn or 2H), designed to have a similar special-pair electron donor and similar charge-separation distances, redox processes and photochemical reaction rates to those in the natural PRC from purple bacteria, have been synthesised and extensive photochemical studies performed. Mechanisms of electron-transfer reactions are fully investigated using femtosecond and nanosecond transient absorption spectroscopy. In benzonitrile, all models show picosecond-timescale charge-separations and the final singlet charge-separations with the microsecond-timescale. The established lifetimes are long compared to other processes in organic solar cells or other organic light harvesting systems. These rigid, synthetically flexible molecules provide the closest mimics to the natural PRC so far synthesised and present a future direction for the design of light harvesters with controllable absorption, redox, and kinetics properties
The fate of trace organic contaminants during anaerobic digestion of primary sludge: A pilot scale study
© 2018 A pilot-scale study was conducted to investigate the fate of trace organic contaminants (TrOCs) during anaerobic digestion of primary sludge. Of the 44 TrOCs monitored, 24 were detected in all primary sludge samples. Phase distribution of TrOCs was correlated well with their hydrophobicity (>67% mass in the solid phase when LogD > 1.5). The pilot-scale anaerobic digester achieved a steady performance with a specific methane yield of 0.39–0.92 L/gVSremoved and methane composition of 63–65% despite considerable variation in the primary sludge. The fate of TrOCs in the aqueous and solid phases was governed by their physicochemical properties. Biotransformation was significant (>83%) for five TrOCs with logD 1.5 were poorly removed under anaerobic conditions. Sorption onto the solid phase appears to impede the biodegradation of these TrOCs
Occurrence and bioconcentration of micropollutants in Silver Perch (Bidyanus bidyanus) in a reclaimed water reservoir
© 2018 This study examined the occurrence of 49 micropollutants in reclaimed water and Silver Perch (Bidyanus bidyanus) living in a reclaimed water reservoir. The numbers of micropollutants detected in reclaimed water, Silver Perch liver, and Silver Perch flesh were 20, 23, and 19, respectively. Concentrations of all micropollutants in reclaimed water, except benzotriazole, were well below the Australian Guideline for Recycled Water (AGRW) values for potable purposes. The concentration of benzotriazole in reclaimed water was 675 ± 130 ng/L while the AGRW value for this compound was 7 ng/L. Not all micropollutants detected in the water phase were identified in the Silver Perch flesh and liver tissues. Likewise, not all micropollutants detected in the Silver Perch flesh and liver were identified in the reclaimed water. In general, micropollutant concentrations in the liver were higher than in the flesh. Perfluorooctane sulfonate (PFOS) was detected at a trace level in reclaimed water well below the AGRW guideline value for potable purposes, but showed a high and medium bioconcentration factor in Silver Perch liver and flesh, respectively. In addition, the risk quotient for PFOS was medium and high when considering its concentration in Silver Perch liver and flesh, respectively. Results reported here highlight the need to evaluate multiple parameters for a comprehensive risk assessment. The results also single out PFOS as a notable contaminant of concern for further investigation
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