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Chemical looping combustion is a promising technology for the capture of CO 2 involving redox materials as oxygen carriers. The effects of reduction conditions, namely, temperature and fuel partial pressure on the conversion products are investigated. The experiments were conducted in a laboratory fixed-bed reactor that was operated cyclically with alternating reduction and oxidation periods. Reactions are assumed to occur in the shell surrounding the particle grains with diffusion of oxygen to the surface from the grain core. Activation energies for the shell and core reactions range from 9 to 209 kJ/mol depending on the reaction step. [ABSTRACT FROM AUTHOR]

Introduction:Dynamin-related protein 1 (DRP1) is a large GTPase that mediates mitotic fission (the division of mitochondria which is coordinated with mitosis, ensuring equitable distribution of mitochondria to daughter cells). In pulmonary arterial hypertension (PAH) pulmonary artery smooth muscle cells (PASMC), mitotic fission, and DRP1 activity are increased, contributing to its hyperproliferative phenotype. We investigated the therapeutic efficacy of Drpitor1a, a novel, small molecule, Drp1 GTPase inhibitor, in a rat PAH model.Methods:A single dose of monocrotaline (MCT, 60mg/kg, SC) or PBS was injected to female Sprague-Dawley rats on day 0 (n=20 for MCT and n=15 for PBS). On day 14, the development of PAH was confirmed by echocardiography and the rats were randomized for treatments. An indwelling catheter was implanted through the left jugular vein on day 15. Drpitor1a (1mg/kg) or normal saline (NS) was administered by IV every 48 hours from day 17 to day 27. Right ventricular (RV) structure and function were assessed on day 28 with echocardiography. Pulmonary hemodynamics was evaluated on day 29 using right heart catheterization (RHC).Results:MCT rats developed PAH with RV dysfunction on day 14. There was no statistical difference between the Drpitor1a and NS groups at randomization. At the endpoint, MCT+Drpitor1a rats, vs. MCT+NS rats, had a significantly reduced severity of pulmonary hypertension evident as longer pulmonary artery acceleration time (PAAT) and lower pulmonary vascular resistance index. Drpitor1a also improved RV function, evident as greater RV free wall thickening (RVFWT%), increased tricuspid annular plane systolic excursion (TAPSE), and increased cardiac index (CI). Drpitor1a regressed pulmonary artery medial thickening and inhibited RV hypertrophy without hepatological, renal or hepatic toxicities.Conclusion:Drpitor1a is a safe and effective treatment for preclinical PAH.

Introduction.Takotsubo Syndrome (TS) has been associated with acute stress exposure and excessive activation of the adrenergic nervous system. Less is known about the role of chronic stress and of the hypothalamic-pituitary-adrenal (HPA) axis in the pathophysiology of TS. Hair cortisol concentration (HCC) is a novel biomarker of chronic stress and HPA axis activation. Plasma cortisol is incorporated in growing hair (average growth rate = 1 cm/month), reflecting HPA axis activity over the preceding months. In this study we measured HCC in TS patients and explored associations between HCC, trigger status, and psychological characteristics at enrollment.Methods.HCC was measured in a group of patients admitted with a new TS diagnosis based on Mayo Clinic criteria (n=18). Demographics, perceived stress, depression, anxiety, PTSD symptoms, coping skills, and resilience (self-report questionnaires); trigger history (standardized in-person interview); and HCC were collected at the baseline visit. Hair strands were cut near the scalp from a posterior vertex position. HCC was measured in the first 3 cm of hair, which reflects plasma cortisol levels during the previous 3 months. Samples were washed, ground, extracted in HPLC-grade methanol, and quantified (pg/mg) using a high-sensitivity enzyme immunoassay (EIA) kit. Descriptive statistics were used to characterize the sample, and Spearman rho to examine associations. A p value (2-sided) < .05 was considered significant.Results.Participants were 65.6 (SD 9.4) years old, 100% female, 100% white, 10% Hispanic. 52% married/living as married. Median HCC was 6.35 pg/mg (IQR 3.6, 15.2). HCC was significantly higher in patients reporting no triggers vs. those reporting a trigger prior to the TS episode (14.9 vs. 6.8 pg/ml, p=0.03). No associations were found between psychological measures and HCC, except for a non-significant inverse association between HCC and PTSD symptoms (rho=-0.35; p=0.14).Conclusions.This first exploration of HCC levels in patients with a recent TS episode suggests that chronic HPA axis activation likely does not play a role in the pathophysiology of TS. Findings need to be confirmed in a controlled study with a larger and more diverse sample.

Optical design and testing has numerous applications in industrial, military, consumer, and medical settings. Assembling a complete imaging or nonimage optical system may require the integration of optics, mechatronics, lighting technology, optimization, ray tracing, aberration analysis, image processing, tolerance compensation, and display rendering. This issue features original research ranging from the optical design of image and nonimage optical stimuli for human perception, optics applications, bio-optics applications, 3D display, solar energy system, opto-mechatronics to novel imaging or nonimage modalities in visible and infrared spectral imaging, modulation transfer function measurement, and innovative interferometry.

Several letters to the editor are presented in response to articles in the February 2014 issue including "Imagine All the People," by Colonel Robert J. Sallee, "Compensation Controversies," and "Mission Accomplished."

Mutations in the catalytic subunit of protein kinase A (PKAc) drive the stress hormone disorder adrenal Cushing’s syndrome. We define mechanisms of action for the PKAc-L205R and W196R variants. Proximity proteomic techniques demonstrate that both Cushing’s mutants are excluded from A kinase-anchoring protein (AKAP)-signaling islands, whereas live-cell photoactivation microscopy reveals that these kinase mutants indiscriminately diffuse throughout the cell. Only cAMP analog drugs that displace native PKAc from AKAPs enhance cortisol release. Rescue experiments that incorporate PKAc mutants into AKAP complexes abolish cortisol overproduction, indicating that kinase anchoring restores normal endocrine function. Analyses of adrenal-specific PKAc-W196R knockin mice and Cushing’s syndrome patient tissue reveal defective signaling mechanisms of the disease. Surprisingly each Cushing’s mutant engages a different mitogenic-signaling pathway, with upregulation of YAP/TAZ by PKAc-L205R and ERK kinase activation by PKAc-W196R. Thus, aberrant spatiotemporal regulation of each Cushing’s variant promotes the transmission of distinct downstream pathogenic signals.

Much emphasis has been placed on the impact of falls among older adults, and the relationship between polypharmacy and falls in community-dwelling elders. As home healthcare agencies' critical role in the continuum of care is recognized, so is the responsibility for ensuring that quality patient outcomes are achieved resulting in reduced hospitalizations. As we examined the factors involved in falls and hospitalizations with our home care population, it became evident that the pharmacist plays a critical role in helping to ensure that risk factors associated with falls are minimized through a thorough medication therapy review, completed in collaboration with the case manager and the physician. This project was initiated to positively impact patient outcomes by identifying potential medication issues in those patients who were also identified as high fall risk.

Reporter gene assays (RGAs) are commonly used to measure biological pathway modulation by small molecules. Understanding how such compounds interact with the reporter enzyme is critical to accurately interpret RGA results. To improve our understanding of reporter enzymes and to develop optimal RGA systems, we investigated eight reporter enzymes differing in brightness, emission spectrum, stability, and substrate requirements. These included common reporter enzymes such as firefly luciferase (Photinus pyralis), Renilla reniformisluciferase, and β-lactamase, as well as mutated forms of R. reniformisluciferase emitting either blue- or green-shifted luminescence, a red-light emitting form of Luciola cruciatafirefly luciferase, a mutated form of Gaussia princepsluciferase, and a proprietary luciferase termed “NanoLuc” derived from the luminescent sea shrimp Oplophorus gracilirostris. To determine hit rates and structure–activity relationships, we screened a collection of 42,460 PubChem compounds at 10 μM using purified enzyme preparations. We then compared hit rates and chemotypes of actives for each enzyme. The hit rates ranged from <0.1% for β-lactamase to as high as 10% for mutated forms of Renillaluciferase. Related luciferases such as Renillaluciferase mutants showed high degrees of inhibitor overlap (40–70%), while unrelated luciferases such as firefly luciferases, Gaussialuciferase, and NanoLuc showed <10% overlap. Examination of representative inhibitors in cell-based assays revealed that inhibitor-based enzyme stabilization can lead to increases in bioluminescent signal for firefly luciferase, Renillaluciferase, and NanoLuc, with shorter half-life reporters showing increased activation responses. From this study we suggest strategies to improve the construction and interpretation of assays employing these reporter enzymes.

Anatase phase TiO2and related alloyed TiO2:N and TiO2:Nb congeners have been prepared by sol–gel processing techniques. The coalloyed TiO2:(Nb,N)-1composition, in which niobium substitutes for titanium on the cation sublattice and nitrogen appears in either chemisorbed or interstitial sites as well as substitutes for oxygen on the anion sublattice, has also been prepared. EPR spectroscopy performed on the coalloyed material at 4 K shows that the bulk material contains minor impurities of Ti3+and F+centers. Annealing this compound under oxygen oxidizes the material to give TiO2:(Nb,N)-2, which is EPR silent. All alloyed compositions show surface areas of 41–68 m2/g, different from the 2 m2/g for TiO2. In addition, the monoalloyed compounds show band gaps that are not significantly different than that of the parent TiO2composition (3.2 eV), whereas the coalloyed compound TiO2:(Nb,N)-1shows a significantly lower energy absorption edge of 2.0 eV. Each composition was tested for its ability to photodegrade methylene blue (MB) dye catalytically, and the coalloyed composition TiO2:(Nb,N)-1shows a 7-fold increase in rate (1.203 h–1) compared to the parent TiO2phase. The oxygen annealed version, TiO2:(Nb,N)-2, shows a rate of only 0.234 h–1, leading to the conclusion that bulk Ti3+and/or F+centers serve as catalytic sites for MB degradation.

The purpose of this study was to test the hypothesis that with improved technology, the presence of abscess in a postoperative fluid collection may be prospectively made. This is an Institutional Review Board-approved, Health Insurance Portability and Accountability Act-compliant retrospective review of computed tomography (CT)-guided intra-abdominal fluid collection drainages. The diagnostic CT scans of 95 consecutive patients performed on 16- and 64-multidetector CT (MDCT) were reviewed by four readers with varying abdominal imaging expertise. Readers were asked to determine fluid content, to document whether infection was present, and to rate reader confidence for infection. A fifth radiologist reviewed the collections for imaging characteristics. The gold standard for presence of infection was microbiological Gram stain and culture. The logistic regression model showed that both fluid collections containing gas or high attenuation fluid (average CT density 20 or greater Hounsfield units) are significant predictors of infection (P= 0.001). The average sensitivity over the four readers for determining presence of infection was 83.4 per cent and specificity was 39.3 per cent. Even in the era of MDCT, the ability to predict whether or not a fluid collection is infected or not, based on imaging findings alone, is limited. Presence of gas is a strong indicator of infection, but no imaging finding is characteristic of a sterile fluid collection.

Micro-patterned thin films interrogated in the Kretschmann configuration of SPR could extend the detection range to lower concentrations and small biomolecules due to a greater sensitivity. This was achieved with the same instrumentation and analysis methodologies developed for SPR with continuous films. The plasmonic properties of micro-patterned thin films composed of various layers of Ag and Au were investigated to find an optimal structure for biosensing application. The analytical parameters and biosensing performances were also evaluated for analysis of biological samples. Au microhole arrays of 3.2 m periodicity and 1.6 m hole diameter were prepared using a modified nanosphere lithography (NSL) technique. These microstructures showed optimal plasmonic properties for biosensing applications as they exhibit a 50% increase in sensitivity to refractive index changes compared to continuous thin films of the same thickness. Moreover, microhole arrays presented a faster response time to refractive index changes while analytical parameters such as the resolution and the noise in biosensing measurement were comparable to continuous films. When combined to the appropriate surface chemistry, a greater SPR response was measured for proteins using microhole arrays. Although microhole arrays required an additional preparation step, a cleaning step using oxygen plasma allowed multiple measurements with the same metallic surface with great repeatability. Hence, microhole arrays proved to be a simple approach to improve current SPR biosensing technique. Further investigations to understand the plasmonic properties of microhole were performed using an angle scanning SPR instrument.

Little is known about the long-term outcomes of obese living kidney donors (OLKDs). We undertook this study to describe renal outcomes of OLKDs several years after donation.

Little is known about the long-term outcomes of African American living kidney donors (AALKDs). We undertook this study to describe renal outcomes of AALKDs several years after donation.

This article presents letters to the editor in response to articles in previous issues including responses to an article about slowing down for the first six miles of a marathon to improve overall time. Responses to readers' questions about this slowdown technique are answered by running coach, Guy Avery.

Introduction:In Canada, acute asthma is a common cause of emergency department (ED) attendance and its treatment is affected by ED overcrowding and increasing wait times. Literature suggests that a clinical pathway (CP) for the treatment of acute asthma can increase the use of medical therapy, reduce hospital admission rates and decrease associated costs. However, only few have looked at the effect on ED length of stay (ED LOS) when such a CP is initiated by triage nurse/respiratory therapist among adults. In this optic, an asthma CP was launched on Feb. 2016 at Centre Hospitalier Universitaire de Sherbrooke (QC) and included medical directives allowing triage nurse and respiratory therapist initiation of treatment. Methods:The objectives are to determine the effect of an ED nurse/respiratory therapist-initiated asthma CP on (1) ED LOS, (2) time-to-treatment (beta-agonist, corticosteroids), time-to-MD and other secondary outcomes. This was a retrospective before-after study. Adults presenting to the ED before and after CP implementation with a final diagnosis of asthma or asthma exacerbation were eligible. The groups A (before implementation) and B (after implementation) were compared for ED LOS. Three subgroups of 50 patients were generated and compared for outcomes: A1 (before implementation), B1 (after implementation without CP) and B2 (after implementation with CP). All five groups were controlled for triage level and sex. Results:In total, 1086 patients were included; 543 before implementation (Mar. 2011 – Feb. 2016) and 543 after (Feb. 2016 – Jun. 2019), of whom 14% (N = 77) were treated by CP. The average ED LOS was similar (10.36h vs 10.65h; (p = 0,31)) in group A and in group B. In groups A1, B1 and B2, the median ED LOS were respectively 6.00, 6.84, 4.80; these differences were not statistically significant. The average time-to-treatment for beta-agonist in A1, B1 and B2 was respectively 148, 180 and 50 mins; the differences between B2 and A1 and between B2 and B1 were both statistically significant (p < 0,05). Conclusion:Although this study indicates a low compliance to the CP, it shows that time-to-treatment can be reduced. It didn't demonstrate any statistically significant decrease in ED LOS, most likely due to low number of patients and non-normal distribution, but the 1.2h shorter could be a major advantage if it proves true. Further studies are essential to understand facilitators and alleviate the barriers in anticipation of a multi-centric implementation.

Gingival diseases are the most widely held diseases in America. In some patients, periodontal disease appears in a generalized form, but more often it appears in localized areas. Furthermore, after treatment with scaling and root planing (SRP) in generalized cases, the disease is often reduced to a few local areas in the patient's mouth. Since periodontitis is a bacterial infection with known pathogenic microorganisms, the local delivery of antimicrobials has been considered to be a possible solution for treating and controlling localized forms of periodontal disease.Three current local chemotherapeutic agents are reviewed in this paper: doxycycline gel, chlorhexidine chip and minocycline microspheres. With the advancement of local drug delivery systems, clinicians and their patients have new alternatives for treatment of periodontal disease. [ABSTRACT FROM AUTHOR]

Corticotropin-releasing hormone (CRH) is a major regulator of adrenocorticotropic hormone and the production of glucocorticoids by the adrenal gland. Abnormal regulation of CRH and endogenous glucocorticoids has been implicated in the pathogenesis of asthma.

The question of whether distinct or similar neural substrates underlie primary emotions has not been resolved yet. To address this issue, we used fMRI to scan professional actors during self-induced states of sadness and happiness. Results demonstrated that, relative to an emotionally Neutral state, both the Sad and the Happy states were associated with significant loci of activation, bilaterally, in the orbitofrontal cortex, and in the left medial prefrontal cortex, left ventrolateral prefrontal cortex, left anterior temporal pole, and right pons. These loci of activation were localized distinctly within these regions, that is, in different sub-regions. These results suggest that sadness and happiness may be associated with similar brain regions but distinct sub-regions and neural circuits.

Animal studies and observations of neglect patients suggest that the posterior parietal cortex is part of a system that codes egocentred space. Few studies show the existence of areas involved in the representation of egocentred space in healthy humans. We investigated with fMRI and a conjunction protocol, the overlap of activity between optokinetic stimulation and a task of midline computation. Results showed that the right posterior parietal and frontal cortices were involved in both tasks (p<0.0001). The evidence presented in this study provides the neuroanatomical substrate involved in the recovery of neglect during vestibular stimulation. This last point is of clinical interest for the rehabilitation of hemineglect.

Gingival diseases are the most widely dispersed diseases in the United States. In some patients, periodontal disease appears in a generalized form, but more often it appears in localized areas. Furthermore, after treatment with scaling and root planing in generalized cases, the disease is often reduced to a few local areas in the patient's mouth. Because periodontitis is a bacterial infection with known pathogenic microorganisms, the local delivery of antimicrobial agents has been considered to be a possible solution for treating and controlling localized forms of periodontal disease. Three local chemotherapeutic agents are reviewed in this paper: tetracycline fiber, doxycycline gel, and chlorhexidine chip. With the advancement of local drug delivery systems, restorative dentists, periodontists, and their patients have new alternatives for the treatment of periodontal disease. Local chemotherapeutic agents offer an additional mode of therapy and should be used on a case-by-case basis, not necessarily as an initial treatment.

Periodontal diseases are oral disorders characterized by inflammation of the supporting tissues of the teeth. Usually, periodontitis is a progressively destructive loss of bone and periodontal ligament (loss of the attachment apparatus of the teeth). Periodontitis has documented risk factors, including but not limited to specific plaque bacteria, smoking, and diabetes mellitus. Initially, the link between systemic disease and periodontal diseases was thought to be unidirectional. Currently, there is increasing evidence that the relationship between these entities may be bidirectional. Recent case-control and cross-sectional studies indicate that periodontitis may confer a 7-fold increase in risk for preterm low birth weight infants and a 2-fold increase in risk for cardiovascular disease. These early reports indicate the potential association between systemic and oral health. Additionally, these studies support the central hypothesis that periodontal disease involves both a local and a systemic host inflammatory response. This knowledge of disease interrelationships may prove vital in intervention strategies to reduce patient risks and prevent systemic disease outcomes. Based on the current evidence of the periodontal-systemic disease connection, the purpose of this report is to help establish the groundwork for closer communication between physicians and periodontists in the military health care setting.

In the study reported in this paper, we characterized PACAP in the human fetal adrenal gland and we investigated the effect of PACAP on steroid secretion from cultured fetal adrenal cells. The adrenal gland from 20-week-old fetuses contained substantial concentrations of PACAP-immunoreactive material (88.6 ngg wet tissue). HPLC analysis of adrenal extracts revealed the presence of both PACAP27 and PACAP38, the latter being the predominant form. Incubation of cultured fetal adrenal cells with PACAP38 (10?7M) significantly increased cortisol and DHEAS secretion. Administration of the ?-adrenoreceptor agonist isoproterenol mimicked the stimulatory effect of PACAP on both steroid secretion whereas preincubation of fetal cells with the ?-adrenoreceptor antagonist propranolol suppressed the steroidogenic effect of PACAP. These data, together with the observation that PACAP receptors are exclusively located on chromaffin cells, suggest that, in the fetal human adrenal gland, the effect of PACAP on steroid secretion is mediated via the local release of catecholamines.

Early-onset periodontal diseases are often diagnosed in the military as a result of the requirements for annual dental examinations and the youthful population served. A young soldier diagnosed with rapidly progressive periodontitis completed initial therapy of root planing with the systemic antibiotic doxycycline but was poorly compliant with additional treatment. During a subsequent mandatory dental examination, new radiographs demonstrated a significant improvement in the quantity and quality of alveolar bone, illustrating the regeneration potential of the young patient with early-onset periodontal disease.

Alveolar ridge deformities are usually the result of trauma, periodontal disease, surgical insult, or developmental defects. Preventing ridge collapse with the extraction of maxillary anterior teeth is vital to an esthetic restorative result. Several techniques are available to prevent ridge collapse. In these case presentations, ridge preservation was achieved utilizing an acellular dermal matrix as a barrier membrane with a demineralized freeze‐dried bone allograft. This report demonstrated an acceptable esthetic result with no loss of ridge height or width. Soft tissue dimensions were also preserved. The two graft materials were well accepted by the body and healing was rapid and without significant discomfort. The technique illustrated provides the surgeon with another option to prevent ridge collapse and ultimately improve esthetics.J Periodontol 2000;71:1353‐1359.