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Type 2 diabetes (T2D) is characterised by the loss of first-phase insulin secretion. We studied mice with β-cell selective loss of the glucagon receptor (Gcgr fl/fl X Ins-1 Cre ), to investigate the role of intra-islet glucagon receptor (GCGR) signalling on pan-islet [Ca2+] I activity and insulin secretion. Metabolic profiling was conducted on Gcgr β-cell−/− and littermate controls. Crossing with GCaMP6f (STOP flox) animals further allowed for β-cell specific expression of a fluorescent calcium indicator. These islets were functionally imaged in vitro and in vivo. Wild-type mice were transplanted with islets expressing GCaMP6f in β-cells into the anterior eye chamber and placed on a high fat diet. Part of the cohort received a glucagon analogue (GCG-analogue) for 40 days and the control group were fed to achieve weight matching. Calcium imaging was performed regularly during the development of hyperglycaemia and in response to GCG-analogue treatment. Gcgr β-cell−/− mice exhibited higher glucose levels following intraperitoneal glucose challenge (control 12.7 mmol/L ± 0.6 vs. Gcgr β-cell−/− 15.4 mmol/L ± 0.0 at 15 min, p = 0.002); fasting glycaemia was not different to controls. In vitro , Gcgr β-cell−/− islets showed profound loss of pan-islet [Ca2+] I waves in response to glucose which was only partially rescued in vivo. Diet induced obesity and hyperglycaemia also resulted in a loss of co-ordinated [Ca2+] I waves in transplanted islets. This was reversed with GCG-analogue treatment, independently of weight-loss (n = 8). These data provide novel evidence for the role of intra-islet GCGR signalling in sustaining synchronised [Ca2+] I waves and support a possible therapeutic role for glucagonergic agents to restore the insulin secretory capacity lost in T2D. • Beta-cell selective loss of the glucagon receptor (Gcgr β-cell−/− ) results in defective insulin secretion. • Gcgr β-cell−/− islets display reduced ability for calcium waves to propagate and reduced beta-cell connectivity. • Long-term glucagon therapy reverts the loss of beta-cell calcium waves and dysglycaemia associated with diet induced obesity. [ABSTRACT FROM AUTHOR]

The average photon energy ( APE ) is commonly used as a means to classify solar irradiance based on the relative distribution of energy over the spectrum. Prior studies have shown a single APE can identify a unique spectral irradiance distribution with low standard deviation, but have not demonstrated this distribution will be the same across different geographic locations. This paper investigates this possibility by comparing the spectral distributions of global horizontal irradiance from two different locations, indexed by APE value. The APE is shown to be a strong predictor of spectral irradiance distribution for the two datasets after they are filtered to remove low irradiance data. Comparing the irradiance data from the two locations showed that the same APE value defines very similar distributions for global horizontal spectral irradiance recorded at the sites considered. This raises the possibility of using the APE value as a quality control for spectral irradiance measurements. [ABSTRACT FROM AUTHOR]

Objectives: To examine the association of neuropsychiatric symptom (NPS) severity with risk of transition to all-cause dementia, Alzheimer disease (AD), and vascular dementia (VaD).Design: Survival analysis of time to dementia, AD, or VaD onset.Setting: Population-based study.Participants: 230 participants diagnosed with cognitive impairment, no dementia (CIND) from the Cache County Study of Memory Health and Aging were followed for a mean of 3.3 years.Measurements: The Neuropsychiatric Inventory (NPI) was used to quantify the presence, frequency, and severity of NPS. Chi-squared statistics, t-tests, and Cox proportional hazard ratios were used to assess associations.Results: The conversion rate from CIND to all-cause dementia was 12% per year, with risk factors including an APOE ε4 allele, lower Mini-Mental State Examination, lower 3MS, and higher CDR sum-of-boxes. The presence of at least one NPS was a risk factor for all-cause dementia, as was the presence of NPS with mild severity. Nighttime behaviors were a risk factor for all-cause dementia and of AD, whereas hallucinations were a risk factor for VaD.Conclusions: These data confirm that NPS are risk factors for conversion from CIND to dementia. Of special interest is that even NPS of mild severity are a risk for all-cause dementia or AD. [ABSTRACT FROM AUTHOR]

Background: Evidence suggests that cardiovascular medications, including statins and antihypertensive medications, may delay cognitive decline in patients with Alzheimer dementia (AD). We examined the association of cardiovascular medication use and rate of functional decline in a population-based cohort of individuals with incident AD. Methods: In the Dementia Progression Study of the Cache County Study on Memory, Health, and Aging, 216 individuals with incident AD were identified and followed longitudinally with in-home visits for a mean of 3.0 years and 2.1 follow-up visits. The Clinical Dementia Rating (CDR) was completed at each follow-up. Medication use was inventoried during in-home visits. Generalized least-squares random-effects regression was performed with CDR Sum of Boxes (CDR-Sum) as the outcome and cardiovascular medication use as the major predictors. Results: CDR-Sum increased an average of 1.69 points annually, indicating a steady decline in functioning. After adjustment for demo- graphic variables and the baseline presence of cardiovascular conditions, use of statins = 0.03) and beta-blockers (p = 0.04) was associated with a slower annual rate of increase in CDR-Sum (slower rate of functional decline) of 0.75 and 0.68 points respectively, while diuretic use was associated with a faster rate of increase in CDR-Sum (p = 0.01; 0.96 points annually). Use of calcium-channel blockers, angiotensin-converting enzyme inhibitors, digoxin, or nitrates did not affect the rate of functional decline. Conclusions: In this population-based study of individuals with incident AD, use of statins and beta-blockers was associated with delay of functional decline. Further studies are needed to confirm these results and to determine whether treatment with these medications may help delay AD progression. [ABSTRACT FROM AUTHOR]

Abstract: While characterizing the kinetic parameters of apoplastic phenolic oxidation by peroxidase, we found anomalies caused by the Mes [2-(4-morpholino)ethanesulfonic acid] buffer being used. In the presence of Mes, certain phenolics appeared not to be oxidized by peroxidase, yet the oxidant, H2O2, was utilized. This anomaly seems to be due to the recycling of the phenolic substrate. The reaction is relatively inefficient, but at buffer concentrations of 10 mM or greater the recycling effect is nearly 100% with substrate concentrations less than 100 μM. The recycling effect is dependent on substrate structure, occurring with 4′-hydroxyacetophenone but not with 3′,5′-dimethoxy-4′-hydroxyacetophenone (acetosyringone). Characterization of the reaction parameters suggests that the phenoxyl radical from the peroxidase reaction interacts with Mes, causing the reduction and regeneration of the phenol. Similar responses occurred with related buffers such as Hepes [4-(2-hydroxyethyl)piperazine-1-ethanesulfonic acid] and Pipes [piperazine-1,4-bis(2-ethanesulfonic acid)]. Results from this work and other reports in the literature indicate that great care is required in interpreting any results involving these buffers under oxidizing conditions. [Copyright &y& Elsevier]

The plant apoplast is one of the first battlegrounds for pathogens invading via leaf stomata. The apoplast is the border just outside the cell membrane and in a leaf, much of the apoplast is in direct contact or near the air space within the leaf. It is one of the most accessible parts of the plant for the study of early events in the bacteria/plant interactions and likewise it offers lucrative possibilities for plant disease control. Recent studies have shown that two simple phenolics, acetovanillone and acetosyringone, respond to bacterial infection within the first few hours after inoculation, but their timing and concentrations vary depending on the type of interaction: saprophytic, susceptible, or resistant. Here we describe a second phase of the interaction, about 10h post inoculation, in which chlorogenic acids increase dramatically in pathogenic interactions, susceptible and resistant. Chlorogenic acid is stored in the plant vacuole and its appearance indicates leakage across the apoplast/membrane barrier, which in turn is likely to affect bacterial growth. Therefore we have tried to correlate bacterial multiplication with these chemical events in the three types of interactions. The oxidative environment of the apoplast during these early periods suggests that these phenolic compounds may influence the redox environment and directly inhibit bacterial multiplication during certain periods of the interaction. [ABSTRACT FROM AUTHOR]

A metal-supported solid oxide fuel cell (MS-SOFC) consisting of infiltrated NiMo/CZ internal reforming catalysts is operated under a direct ethanol feed condition at 700 °C with a steam-to-carbon (S/C) ratio of 2. The additional catalyst functional layer is required to internally reform the ethanol fuel into syngas while preventing the cell's rapid deactivation due to unwanted carbon deposits or coking. Our experimental results show that the cell with NiMo/CZ catalyst shows a higher maximum current density of 0.355 A cm−2 compared to 0.052 A cm−2 for the cell without catalyst at 0.4 V. The constant current stability performance was also improved. The cell with NiMo/CZ can operate for 90 h and shows less carbon deposition than the cell without a catalyst. Adding NiMo/CZ reforming catalyst into the MS-SOFC is a promising solution to enhance the operating lifetime and coke resistance in the ethanol steam reforming fed MS-SOFC system. [Display omitted] • Non-noble metal catalyst infiltration into metal-supported SOFC (MS-SOFC). • MS-SOFC with the catalyst operates under direct-ethanol feed conditions. • MS-SOFC with the catalyst shows an enhanced synthesis gas production rate. • MS-SOFC with the catalyst offers increased coking resistance. • MS-SOFC with the catalyst offers enhanced structural stability. [ABSTRACT FROM AUTHOR]

We evaluated bird community response to type, amount, and dispersionof trees, snags, and shrubs that were retained at harvest in mixedwood boreal forests of Alberta, Canada. We also evaluated whether the degree of similarity between bird communities in harvest and old-growth areas was related to the type and amount of materials retained at harvest. We combined data from three separate studies to generate a large data set covering a wide range of cut-block structures. Birds were surveyed using point counts and line transects. Residual vegetationwas surveyed partially on the ground, and partially from aerial photographs. Bird species commonly associated with parkland and open country habitats had high densities in harvest areas that contained abundant shrubs and few residual trees or snags. Within harvest areas where more trees, particularly large deciduous trees, were retained, and when those trees were retained in clumps, bird communities were more similar to those found in old-growth forests. Thus, by retaining clumps of large trees and snags in harvest areas managers may be able to create habitats that are used by old-growth forest bird species. However, for many forest birds, density was lower in cut-blocks with residual trees and snags than it was in old-growth forest. Results shouldbe interpreted cautiously because survival and reproductive success of forest birds in cut-blocks with residual trees and snags was not determined. [ABSTRACT FROM AUTHOR]

Abstract: Sunshine duration can be estimated using photovoltaic solar cells instead of conventional pyranometers or pyrheliometers, which are more expensive and therefore not suitable for low cost measurement applications in developing regions. A one-year meteorological dataset from Nicosia (Cyprus) including direct irradiance, global irradiance from a pyranometer and global irradiance from a reference PV cell was used to calculate sunshine duration following the WMO pyrheliometric method and three pyranometric methods by WMO Slob and Monna, Hinssen–Knap and Olivieri. Pyranometric algorithms were adapted to the tilted pyranometer and reference solar cell. Main results indicate that all the pyranometric algorithms underestimated sunshine duration over the span of a year in Cyprus in comparison with the reference pyrheliometric method; and that results between the pyranometer and the solar cell were comparable. The PV silicon solar cell is capable of measuring sunshine duration on a daily basis with an uncertainty similar to the obtained with a pyranometer when using the Olivieri algorithm. [Copyright &y& Elsevier]

Introduction: Bystander cardiopulmonary resuscitation (BCPR) is strongly advocated by resuscitation councils for paediatric out-of-hospital cardiac arrests (OHCAs). However, there are limited reports on rates of BCPR in children and its relationship with return of spontaneous circulation (ROSC) or survival outcomes.Objective: We describe the rate of BCPR and its association with any ROSC and survival- to- hospital-discharge.Methods: We conducted retrospective analysis of prospectively collected paediatric (<18 years of age) OHCA cases in England; we included specialist registry patients treated by emergency medical services (EMS) with known BCPR status and outcome between January 2014 and November 2018. Data included patient demographics, aetiology, witness status, initial rhythm, EMS, season, time of day and bystander status. Associations between BCPR, and any ROSC and survival-to-hospital-discharge outcomes were explored using multivariable logistic regression.Results: There were 2363 paediatric OHCAs treated across 11 EMS regions. BCPR was performed in 69.6% (1646/2363) of the cases overall (range 57.7% (206/367) to 83.7% (139/166) across EMS regions). Only 34.9% (550/1572) of BCPR cases were witnessed. Overall, any ROSC was achieved in 22.8% (523/2289) and survival to hospital discharge in 10.8% (225/2066). Adjusted odds ratio (aOR) for any ROSC was significantly improved following BCPR compared to no BCPR (aOR 1.37, 95% CI 1.03-1.81), but adjusted odds ratio for survival-to-hospital-discharge were similar (aOR 1.01, 95% CI 0.66-1.55).Conclusions: BCPR was associated with improved rates of any ROSC but not survival-to-hospital-discharge. Variations in EMS BCPR rates may indicate opportunities for regional targeted increase in public BCPR education. [ABSTRACT FROM AUTHOR]

The metal-supported solid oxide fuel cell (MS-SOFC) is of current research interest in the clean energy field due to its high performance, quick start-up, thermal cycle stability, and lower raw material cost compared to the conventional cermet-based SOFC. To efficiently operate a MS-SOFC using complex hydrocarbon and logistic fuels, it is required to introduce an internal reforming catalyst within the anode metal scaffold. This review article discusses some examples of the performance of MS-SOFCs under hydrocarbon and logistic fuels with and without an additional reforming catalyst. We also discuss the performance improvement of conventional cermet-based SOFCs by adding reforming catalysts via the infiltration method. This information can be directly applied to future MS-SOFC applications. Furthermore, this review article proposes possible novel methods such as direct precursor infiltration, catalyst-anode premixing, and atomic layer deposition methods to introduce the reforming catalyst into a MS-SOFC for improving its initial electrochemical performance and long-term stability under hydrocarbon and logistics fuel. • Effects of reforming catalysts on non-hydrogen SOFC were reviewed. • Publication mainly focused on opportunity and challenge of catalyst integration on MS-SOFC. • The study also highlights future reforming catalyst deposition methods for MS-SOFC. [ABSTRACT FROM AUTHOR]

A calcium-doped ceria (Ce 1-x Ca x O 2−δ , 0 ≤ x ≤ 0.3) has been applied as a ceramic support in NiMo-based catalysts for an internal reforming tubular solid oxide fuel cell running on isooctane. Introducing calcium into the CeO 2 -based ceramic was found to improve conductivity of Ce 1-x Ca x O 2−δ. The Ce 0.9 Ca 0.1 O 2−δ (x = 0.10) sample exhibited an optimum conductivity of 0.045 S cm−1 at 750 °C. The transport of oxygen ions in Ce 1-x Ca x O 2−δ promoted the catalytic partial oxidation of isooctane in the NiMo–Ce 1-x Ca x O 2−δ catalyst, which increased the fuel conversion as well as H 2 and CO yields. As a result, the NiMo–Ce 0.9 Ca 0.1 O 2−δ (x = 0.10) catalyst exhibited a high isooctane conversion of 98%, and the H 2 and CO yields achieved 74% and 83%, respectively, for reforming of isooctane and air at the O/C ratio of 1.0 at 750 °C. Furthermore, the NiMo–Ce 0.9 Ca 0.1 O 2−δ catalyst has been applied as an internal reforming layer for an inert-substrate-supported tubular solid oxide fuel cell running on isooctane/air. Due to its high reforming activity, the single cell presented an initial maximum power density of 355 mW cm−2 in isooctane/air at 750 °C and displayed stable electrochemical performance during ~30 h operation. These results demonstrated the application feasibility of the NiMo–Ce 0.9 Ca 0.1 O 2−δ catalyst for direct internal reforming solid oxide fuel cells running on isooctane/air. Image 1 • NiMo–Ce 0.9 Ca 0.1 O 2−δ is found to be an effective reforming catalyst for SOFC. • Conductivity of Ce 0.9 Ca 0.1 O 2−δ support is related to the reforming activity. • Oxygen transport property promotes the catalytic partial oxidation of isooctane. • Good performance stability is obtained for SOFC running on isooctane/air. [ABSTRACT FROM AUTHOR]

The present investigation is focused on improving the performance of molybdenum dioxide (MoO 2 ) by doping with Ti for the partial oxidation (POX) of n -dodecane. Ti-doped MoO 2 nanoparticles were synthesized via solvothermal cracking of polycrystalline MoO 3 microparticles prepared by ultrasonic spray pyrolysis in the presence of a Ti precursor. Partial oxidation of n -dodecane was conducted at 850 °C with an O 2 /C ratio of 0.5. The 6 at% Ti-doped MoO 2 was fully converted into orthorhombic carbide phase (β-Mo 2 C) during the reaction. This carbide sample showed high catalytic activity and stability with conversion and H 2 yield of 94.4% and 86.3% after 24 h on stream, respectively. On the other hand, un-doped MoO 2 was partially converted into the carbide phase during the reaction, which led to mixed oxide and carbide phases. This mixed phase showed poor catalytic activity and rapid deactivation after only 6 h of operation. Our ammonia temperature programmed desorption (TPD) and pyridine diffuse reflectance infrared Fourier transform (DRIFT) tests suggest that the addition of Ti to MoO 2 improves both the density and strength of Lewis acid sites, and hence improves hydrocarbon activation. This increased surface carbon activation would enhance the carburization process of the Ti-doped MoO 2 catalyst and retain the carbide phase under the POX condition. [ABSTRACT FROM AUTHOR]

A Ni-based nanoparticle catalyst was synthesized over a silica support via wet impregnation using either ethylene glycol or water. X-ray diffraction and transmission electron microscopy analysis showed that the particle size of the Ni catalyst prepared using ethylene glycol as the solvent tended to be smaller than that obtained when water was used. The resulting catalysts were tested for performance toward partial oxidation (POX) of isooctane at high weight hourly space velocities (WHSV). The results were compared with those from a Rh-based catalyst, which is commonly used for the same reaction. At a WHSV of 13.8 h −1 , a Ni/SiO 2 catalyst with an average Ni particle size of 6.8 nm exhibits higher catalytic activity and stability with an improved resistance to carbon formation than a Ni/SiO 2 catalyst with an average Ni particle size of 16.6 nm. The catalyst with the smaller Ni particles outperformed the supported Rh catalyst for the POX of isooctane. To further improve the Ni dispersion and enhance its ability to run at even higher WHSVs with milliseconds of residence time, ceria was used as a promoter. The ceria-promoted Ni catalyst was also prepared by the wet impregnation method using ethylene glycol as the solvent. The addition of ceria corresponded with a further reduction in the size of the Ni nanoparticles and improved Ni dispersion. Using the Ni-Ce/SiO 2 catalyst the WHSV could be increased up to 20.0 h −1 while still maintaining its good catalytic activity. At this high WHSV of 20.0 h -1 , the Ni/SiO 2 catalyst without the ceria promoter and the Rh catalyst showed severe deactivation due to the formation of surface carbon deposits. [ABSTRACT FROM AUTHOR]