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Introduction: Laparoscopic lavage and drainage (LLD) emerged as an alternative to Hartmann's procedure (HP) for patients with diverticulitis and uncontained perforation. Although initially popular as a less invasive approach, its use in modern practice is in question. This summary will review the available literature to show techniques, outcomes, and indications. Methods: The literature was reviewed for relevant case studies, randomized trials, prospective series, retrospective analyses, and meta-analyses to define peritoneal lavage and determine the clinical outcomes of peritoneal lavage. Results: LLD can be considered on an individual basis for Hinchey III diverticulitis (purulent peritonitis), but there are several contraindications. The extent of adhesionolysis (limited versus extensive) as well as the management of sites of perforation found during surgery are debated. Most surgeons continue lavage with warm saline until water runs clear and place drains in the operation. Three randomized controlled trials (RCTs), the LADIES, SCANDIV, and DILALA trials compared LLD with either resection and anastomosis or Hartmann's procedure. One other RCT (the LapLAND trial) is still with results pending. The LADIES trial studied LLD versus primary anastomosis and resection in Hinchey III diverticulitis and was terminated early secondary to higher 30-day morbidity in the LLD arm; however, 3-year data showed no significant difference in morbidity and mortality. The SCANDIV trial compared LLD with resection in acute diverticulitis (Hinchey I–III) and saw no difference in 90-day morbidity or mortality; however, it noted higher rates of reoperation in the LLD group. The DILALA trial compared Hinchey III diverticulitis patients undergoing LLD with open HP and found that the LLD group had a lower rate of reoperation at 2 years, but no difference in rates of readmission or mortality. Conclusions: Debate still remains over the technique of LLD and specific indications, as well as outcomes compared with resection and primary anastomosis or HP. [ABSTRACT FROM AUTHOR]

Introduction: Acute diverticulitis represents a significant disease burden in the United States and developed world. This article examines current trends in the treatment of acute diverticulitis and concentrates on the utility of antibiotics in acute uncomplicated cases managed in the outpatient setting. Methods: The literature was reviewed for randomized controlled trials (RCTs) to discern the best practice and recommendations for antibiotics for diverticulitis. The time period included relevant RCTs after 2000. Results: Four recent RCTs examine the use of antibiotics in acute uncomplicated diverticulitis. The AVOD study was an RCT that managed inpatients with either antibiotics or IV fluids alone and demonstrated non-inferiority of non-antibiotic management with respect to recovery, complication rates, or recurrence. The DIABLO trial randomized first episodes of acute uncomplicated diverticulitis admitted to the hospital with antibiotics or supportive care and found no difference in morbidity or mortality between the two groups and longer hospital stay for patients treated with antibiotics. The DINAMO study examined outpatients managed with antibiotics by mouth or without and found no difference in morbidity in 90 day follow-up. The STAND study was the only of these four to use a placebo and found no difference between hospital stay or other adverse events at 30 days. In response to this, the ASCRS, AAFP and other societies now recommend against the routine use of antibiotics in acute uncomplicated diverticulitis. Conclusions: Several quality studies found similar outcomes in cases of acute uncomplicated diverticulitis treated with or without antibiotics. Based on these findings, societal guidelines do not recommend routine antibiotics for acute diverticulitis. [ABSTRACT FROM AUTHOR]

GaN devices play a major role in modern electronics, providing high-power handling, efficient high-frequency operation, and resilience in harsh environments. However, electric field crowding at the edge of the anode often limits its full potential, leading to single-event effects (SEEs) at lower bias voltages under heavy ion radiation. Here, we report on the performance of homojunction GaN vertical PiN diodes with a hybrid edge termination design under heavy ion irradiation, specifically, oxygen ions, chlorine ions, Cf-252 fission fragments, and alpha particles from an Am-241 source. The unique hybrid edge termination (HET) design provides better electric field management, preventing breakdown from occurring at the edge of the anode at lower voltages. The results of this study reveal that these devices exhibit excellent tolerance to 12-MeV oxygen and 16-MeV chlorine ions, owing to their low linear energy transfer (LET) and range in GaN. However, single-event burnout (SEB) is observed during the Cf-252 exposure at about 50% of the diodes' electrical breakdown voltage due to the presence of higher LET and longer-range ions. Optical and scanning electron microscopy (SEM) reveal that the damage that caused by SEB lies close to the center of these devices rather than the anode edge. Devices with junction termination extension (JTE) instead of HET edge termination also show similar SEB when irradiated with Cf-252 fission fragments. Physical damage due to SEB occurs at the edge of the anode for these devices. These comparative results show the benefits of HET for enhancing the resistance of GaN-based PiN diodes to heavy ion irradiation. [ABSTRACT FROM AUTHOR]

The conserved Shugoshin (SGO) protein family is essential for mediating proper chromosome segregation from yeast to humans but has also been implicated in diverse roles outside of the nucleus. SGO's roles include inhibiting incorrect spindle attachment in the kinetochore, regulating the spindle assembly checkpoint (SAC), and ensuring centriole cohesion in the centrosome, all functions that involve different microtubule scaffolding structures in the cell. In Caenorhabditis elegans, a species with holocentric chromosomes, SGO-1 is not required for cohesin protection or spindle attachment but appears important for licensing meiotic recombination. Here we provide the first functional evidence that in C. elegans, Shugoshin functions in another extranuclear, microtubule-based structure, the primary cilium. We identify the centrosomal and microtubule-regulating transforming acidic coiled-coil protein, TACC/TAC-1, which also localizes to the basal body, as an SGO-1 binding protein. Genetic analyses indicate that TAC-1 activity must be maintained below a threshold at the ciliary base for correct cilia function, and that SGO-1 likely participates in constraining TAC-1 to the basal body by influencing the function of the transition zone 'ciliary gate'. This research expands our understanding of cellular functions of Shugoshin proteins and contributes to the growing examples of overlap between kinetochore, centrosome and cilia proteomes. [ABSTRACT FROM AUTHOR]

Creep strength in polycrystalline Ni-based superalloys is influenced by the formation of a rich variety of planar faults forming within the strengthening γ ′ phase. The lengthening and thickening rate of these faults – and therefore the creep rate – depends on an intriguing combination of dislocation interactions at the γ - γ ′ interface and diffusional processes of the alloying elements at the core of the fault tip. The effect of alloy composition on this process is not fully understood. In this work we use correlative high resolution transmission electron microscopy and energy-dispersive X-ray spectroscopy to study the deformation faults in two different Ni-based superalloys with carefully designed ratios of disordering-to-ordering-promoting elements (Co-Cr against Nb-Ta-Ti). The results show that the additions of ordering-promoting elements reduce the diffusional processes required for the faults to lengthen and thicken thus reducing the creep rates found for the higher Nb-Ta-Ti alloy. These insights provide a path to follow in the design of improved grades of creep-resistant polycrystalline alloys beyond 700 ∘ C. [ABSTRACT FROM AUTHOR]

Ion- and terrestrial neutron-induced single-event burnout (SEB) data indicate that a thicker, more lightly doped epitaxial (epi) region significantly increases the threshold at which ion-induced SEB occurs in silicon carbide (SiC) power MOSFETs and junction barrier Schottky (JBS) diodes. Simulations indicate that the reduction of power dissipation along the core of the ion track is responsible for the increased robustness of the devices that have higher breakdown voltage ratings. Implications for circuit design show that using a 3300-V power MOSFET provides a significant increase in SEB threshold margin compared to a 1200-V MOSFET, with minor impact on power dissipation during normal operation. [ABSTRACT FROM AUTHOR]

The Space Ionizing Radiation Environment and Effects (SIRE2) toolkit has been developed to update and extend the tools used by the space and radiation effects community. It includes new environment models, the capability to examine how the environment changes along satellite and other trajectories and batch processing capabilities for both environments and radiation effects on electronics. An overview of the capabilities in the SIRE2 Toolkit is provided, and examples of applying SIRE2 to satellite orbits and arbitrary trajectories are given. Key Points: The calculation options include legacy models, the latest models, and batch calculations of space radiation environments and radiation effectsThe tools allow space radiation environment calculations on segments of orbits and on arbitrary spacecraft trajectoriesSIRE2 provides a new probabilistic model for solar energetic particle peak flux [ABSTRACT FROM AUTHOR]

Heavy-ion data suggest that a common mechanism is responsible for single-event burnout (SEB) in 1200-V power MOSFETs and junction barrier Schottky (JBS) diodes. Similarly, heavy-ion data suggest a common mechanism is also responsible for leakage current degradation in both devices. This mechanism, based on ion-induced, highly localized energy pulses, is demonstrated in simulations and shown to be capable of causing degradation and SEB for both the MOSFETs and JBS diodes. [ABSTRACT FROM AUTHOR]

Recent observations of electrical stress-induced recoverable degradation in InAs/AlSb high-electron mobility transistors (HEMTs) have been attributed to metastable defects in the AlSb layer generated by the injected holes. Here we present a detailed theoretical analysis of the degradation mechanism. We show that recoverable degradation does not require the presence of hot carriers in the vicinity of the defects but the degradation is enhanced when the injected holes become more energetic. The metastable degradation arises without the presence of an energy barrier. A comprehensive survey of candidate defects suggest that substitutional and interstitial oxygen are responsible for the degradation. Therefore, reducing the oxygen contamination during device fabrication is likely to significantly improve the reliability of InAs/AlSb HEMTs. [ABSTRACT FROM AUTHOR]

Objective: To evaluate the quality of recovery in dogs undergoing elective orthopaedic surgery induced with either propofol or a combination of ketamine and diazepam. Materials and Methods: Sixty client‐owned dogs undergoing single‐limb elective orthopaedic procedures were enrolled. Dogs were randomly assigned to receive induction with propofol (4 mg/kg) (group P) or ketamine (5 mg/kg) with diazepam (0.25 mg/kg) (group KD) to which all scorers were blinded. The recovery monitoring period lasted for 1 hour following extubation. The recovery period was video‐recorded for blinded scoring at a later time. Scoring for quality of recovery was carried out using three different systems (lower numbers=better quality): a simple descriptive scale (1 to 5), a visual analogue scale (0 to 10 cm) and a numeric rating scale (0 to 10). Videos were reviewed by three ACVAA board‐certified anaesthesiologist raters. Results: Five dogs were deemed to be ineligible. The mean (±SD) duration of anaesthesia was 260.4 ±57.84 minutes in group KD and 261.1 ±51.83 minutes in group P. There was no difference between groups for time to extubation, head lift or sternal recumbency. The number of dogs having a recovery that was scored overall as bad (mean simple descriptive scale > 4, mean visual analogue scale or numeric rating scale > 5) was not different between groups. Dogs in group KD had significantly lower scores than group P dogs (simple descriptive scale P=0.01, numeric rating scale P=0.03, visual analogue scale P=0.03). Clinical Significance: Induction with ketamine and diazepam resulted in a smoother recovery from anaesthesia than induction with propofol. [ABSTRACT FROM AUTHOR]

A simulation paradigm is proposed to examine the effects of transistor-level degradation produced by total ionizing dose (TID) on top-level system performance parameters. The approach is demonstrated on a command and data handling (C&DH) board for deep-space CubeSats. Simulation and postirradiation measurements of a temperature control loop show that TID degradation changes temperature regulation significantly. [ABSTRACT FROM AUTHOR]

Bulk and silicon-on-insulator (SOI) n-channel FinFETs with fin widths of 15–40 nm and channel lengths of 45 and 1000 nm were irradiated with 1.8 MeV protons at temperatures of 295 and 90 K. Bulk and SOI FinFETs show improved transconductance and steeper subthreshold slopes before irradiation at 90 K than at 295 K. Increased off-state leakage currents are observed for longer channel bulk FinFETs for doses above 300–500 krad (SiO2) for 295 and 90 K irradiation, and at lower doses for shorter channel devices. Threshold-voltage shifts for irradiation up to 1 Mrad(SiO2) are greater for SOI devices at 90 K than at 295 K due to enhanced charge trapping in the buried oxide (BOX). TCAD simulations provide insight into radiation-induced trapped-charge densities in the SOI devices. [ABSTRACT FROM AUTHOR]

1.8-MeV proton irradiation to a fluence of 1014/cm2 does not significantly affect the resistance or low-frequency noise of copper or ruthenium resistors fabricated via modern microelectronic fabrication techniques used to form metal lines. The room-temperature noise of these Cu and Ru resistors is surprisingly similar to that of Cu and Pt metal lines and wires fabricated using late-1970s nanofabrication techniques; however, measurements of the temperature dependence of the noise show that the defect kinetics are quite different among the various materials. A large increase in the noise magnitude observed above 200 K in Cu but not in Ru is consistent with the superior resistance to electromigration that Ru lines have shown, relative to Cu. [ABSTRACT FROM AUTHOR]

Cross sections and failure in time rates for neutron-induced single-event burnout (SEB) are estimated for SiC power MOSFETs using a method based on combining results from heavy ion SEB experimental data, 3-D TCAD prediction of sensitive volumes, and Monte Carlo radiation transport simulations of secondary particle production. The results agree well with experimental data and are useful in understanding the mechanisms for neutron-induced SEB data. [ABSTRACT FROM AUTHOR]

The complications of identifying radiation effects in electromechanical sensors in the presence of mechanical variation are discussed. A corresponding analysis method is developed to separate radiation degradation effects from expected sensing variation due to mechanical tolerances of test fixtures. This is achieved by statistically characterizing the fixture variation for each sensor before irradiation, and evaluating the statistical significance of any sensitivity changes after irradiation. The method is demonstrated using a contactless Hall-effect rotary encoder IC commonly used in robotic systems. Sensitivity changes in measurements relevant to robotic controller design are isolated and quantified as a maximum positioning error of 0.5° and an angular velocity error of 1.5%. These measurements can be used to improve a commercial off-the-shelf robotic system’s tolerance to radiation by designing motion controllers robust to sensitivity changes prior to total device failure. [ABSTRACT FROM AUTHOR]

Laser-induced single-event transients (SETs) are observed in black phosphorus (BP) MOSFETs. The SETs are relatively small, which is consistent with expectations for thin-film fully depleted transistors. The position dependence and the bias-dependence of the measured SETs in BP transistors are investigated to study the charge collection mechanisms. The peak drain current is maximized when the pulsed-laser strikes at the center of the channel region. The amplitudes of the SETs are also relatively independent of the overdrive voltage. The drain-to-source SET current increases when $\vert \text {V}_{\mathrm {DS}}\vert $ increases, due to a shunt effect. [ABSTRACT FROM AUTHOR]

Examines the determination of the minority-carrier diffusion length of polycrystalline silicon materials. Application of the surface photovoltage method; Quality of polycrystalline silicon solar cell material; Absorption spectra of the polycrystalline samples.

This work is original research which is based on data gathered from annual reports and accounts. It covers some 267 businesses which had the largest annual turnovers for manufacturing companies, within Britain, in 1971 and were still in existence in 1979. The data have been subjected to analysis to reveal preferred product-market postures, movements in posture, effects of annual turnover size on strategies, and the effects of being located within specific industries. In comparison with the work of D. F. Channon for the preceding twenty years it can be seen that, on the whole, the trend towards diversification has continued throughout the broad spectrum of British Industry. [ABSTRACT FROM AUTHOR]

A consistently suppressed viral load enables HIV (+) patients to live longer, healthier lives and reduces the probability of transmitting the virus. Since the prevalence of HIV is four times higher among those with psychiatric disorders than in the general population, it is likely that this group would also have greater difficulty remaining in care and achieving viral suppression. A secondary data analysis utilizing screening data from the Preventing AIDS Through Health (PATH) for Triples (PFT) Study were examined to assess HIV load suppression among 254 psychiatric inpatients with comorbid substance use disorders in Philadelphia. Viral load results from the past 12 months were obtained from medical records for 63 inpatients identified as HIV (+). The sample was predominately African American (76%), male (56%), and the average age was 43 years. Psychiatric disorders included depression (64%), schizophrenia (21%), and bipolar disorder (13%) with patients reporting use of alcohol (73%), cocaine (64%), cannabis (29%) and opioids (16%) prior to admission. Among this high risk sample of HIV (+) patients, about one-half (52%) achieved viral suppression, with recent opioid users six times more likely to have a detectable viral load than non-opioid users (OR 6.0; CI 1.1-31.7, p = .035). The 52% viral load suppression rate among psychiatric inpatient was higher than expected, given that the CDC’s national suppression rate among those diagnosed with HIV in the general population is 58%. However, individuals with mental illness and substance use disorders require constant surveillance, monitoring, and supportive services to achieve viral suppression. Many of those who were virally suppressed were engaged in Philadelphia’s extensive treatment network, whereas those who were detectable and enrolled in the PFT intervention were often homeless with unstable psychiatric symptoms and current substance use disorders, particularly opioid abuse. [ABSTRACT FROM AUTHOR]

The design, operation, and performance of a laboratory-scale X-ray computed tomography arrangement that is capable of elevated-temperature deformation studies of superalloys to 800 °C and possibly beyond are reported. The system is optimized for acquisition of three-dimensional (3D) backprojection images recorded sequentially during tensile deformation at strain rates between 10−4 and 10−2 s−1, captured in situ. It is used to characterize the evolution of damage—for example, void formation and microcracking—in Nimonic 80A and Inconel 718 superalloys, which are studied as exemplar polycrystalline alloys with lesser and greater ductility, respectively. the results indicate that such damage can be resolved to within 30 to 50 μm. Collection of temporally and spatially resolved data for the damage evolution during deformation is proven. Hence, the processes leading to creep fracture initiation and final rupture can be quantified in a novel way. [ABSTRACT FROM AUTHOR]

The effect of Nb/Ti ratio on environmentally-assisted crack growth of three prototype Ni-based superalloys is studied. For these alloys, the yield strength is unaltered with increasing Nb/Ti ratio due to an increase in grain size. This situation has allowed the rationalization of the factors influencing damage tolerance at 700 °C. Primary intergranular cracks have been investigated using energy-dispersive X-ray spectroscopy in a scanning transmission electron microscope and the analysis of electron back-scatter diffraction patterns. Any possible detrimental effect of Nb on the observed crack tip damage due to Nb-rich oxide formation is not observed. Instead, evidence is presented to indicate that the tertiary γ′-precipitates are dissolving ahead of the crack consistent with the formation of oxides such as alumina and rutile. Our results have implications for alloy design efforts; at any given strength level, both more and less damage-tolerant variants of these alloys can be designed. [ABSTRACT FROM AUTHOR]

Correlative high-resolution transmission electron microscopy and energy-dispersive X-ray spectroscopy are used to study deformation-induced planar faults in the single-crystal superalloy MD2 crept at 800 °C and 650 MPa. Segregation of Cr and Co at microtwins, anti-phase boundaries (APB), and complex/superlattice extrinsic and intrinsic stacking faults (CESF/SESF and CISF/SISF) is confirmed and quantified. The extent of this is found to depend upon the fault type, being most pronounced for the APB. The CESF/SESF is studied in detail due to its role as a precursor of the microtwins causing the majority of plasticity under these conditions. Quantitative modeling is carried out to rationalize the findings; the experimental results are consistent with a greater predicted velocity for the lengthening of the CESF/SESF—compared with the other types of fault—and hence confirm its role in the diffusion-assisted plasticity needed for the microtwinning mechanism to be operative. [ABSTRACT FROM AUTHOR]

Total ionizing dose effects are investigated on a physically unclonable function (PUF) based on CMOS breakdown. Devices irradiated to 2 Mrad(SiO2) show less than 11% change in current ratio at 1.2 V. The read-out window of programmed PUFs decreases significantly at high-dose proton irradiation, and then recovers back to the original value after annealing. The proton test results for the pFET selector, the unbroken nFET, and the broken nFET indicate that the threshold-voltage shift of the pFET selector contributes mainly to the degradation of the PUF. [ABSTRACT FROM AUTHOR]

A family of novel polycrystalline Ni-based superalloys with varying Ti:Nb ratios has been created using computational alloy design techniques, and subsequently characterized using atom probe tomography and electron microscopy. Phase chemistry, elemental partitioning, and γ′ character have been analyzed and compared with thermodynamic predictions created using Thermo-Calc. Phase compositions and γ′ volume fraction were found to compare favorably with the thermodynamically predicted values, while predicted partitioning behavior for Ti, Nb, Cr, and Co tended to overestimate γ′ preference over the γ matrix, often with opposing trends vs Nb concentration. [ABSTRACT FROM AUTHOR]

The accurate representation of aerosols in climate models requires direct ambient measurement of the size- and composition-dependent particle production fluxes. Here, we present the design, testing, and analysis of data collected through the first instrument capable of measuring hygroscopicity-based, size-resolved particle fluxes using a continuous-flow Hygroscopicity-Resolved Relaxed Eddy Accumulation (Hy-Res REA) technique. The Hy-Res REA system used in this study includes a 3D sonic anemometer, two fast-response solenoid valves, two condensation particle counters, a scanning mobility particle sizer, and a hygroscopicity tandem differential mobility analyzer. The different components of the instrument were tested inside the US Environmental Protection Agency's Aerosol Test Facility for sodium chloride and ammonium sulfate particle fluxes. The new REA system design does not require particle accumulation, and therefore avoids the diffusional wall losses associated with long residence times of particles inside the air collectors of traditional REA devices. A linear relationship was found between the sodium chloride particle fluxes measured by eddy covariance and REA techniques. The particle detection limit of the Hy-Res REA flux system is estimated to be ~3 × 105 m-2 s-1. The estimated sodium chloride particle classification limit, for the mixture of sodium chloride and ammonium sulfate particles of comparable concentrations, is ~6 × 106 m-2 s-1. [ABSTRACT FROM AUTHOR]

Abstract: Atmospheric measurements of aerosol size‐resolved hygroscopicity at submicron sizes are carried out at the United States Army Corps of Engineers Field Research Facility in Duck, North Carolina. The scientific aim of the field deployment is to gain improved understanding of the springtime advection of aerosols from the East Coast of the United States over the Atlantic and help to constrain assessments of anthropogenic particle contributions to the marine boundary layer aerosol budget. Air mass back trajectories show that the aerosol sampled at the coast is largely of continental origin that either gets transported directly from the land or spends some time over the Atlantic Ocean. Aerosol size‐resolved hygroscopicity measurements are consistent with air masses of both continental and marine background that are heavily influenced by the continental outflow. Aitken and accumulation mode mean diameters range from 49.1 ± 1.7 nm to 66.9 ± 0.8 nm and 142.8 ± 1.1 nm to 155.0 ± 2.8 nm, respectively. Hygroscopicity distributions for 96 nm, 188 nm, and 284 nm dry‐sized particles show the mode hygroscopicity parameter range from 0.20 ± 0.01 to 0.54 ± 0.03, suggesting the presence of anthropogenic aerosols. We have used the method described by Royalty et al. (2017) to decompose the hygroscopicity distributions into three distinct classes based on the ambient aerosol hygroscopic properties relative to the hygroscopic properties of a reference compound. The method shows that continental outflow heavily influences aerosol chemical and physical properties at the East Coast, with hygroscopicities of submicron aerosols consistent with sulfate‐containing species (62% to 83%), with small contributions from sodium‐ and carbon‐containing particles (up to 9% and 37%, respectively). [ABSTRACT FROM AUTHOR]

Muon-induced single-event upset cross sections are estimated for a 28-nm static random access memory (SRAM) using Monte Carlo simulations informed by ion test results. As an exercise in modeling with limited information, details of the 28-nm SRAM’s cell structure were not used (and not available) to inform choices of device model parameters such as sensitive volume dimensions and efficiencies. Instead, inferences were made based on heavy-ion and proton single event upset data. Volume dimensions were sufficiently small to resolve the charge collection profile resulting from highly localized low linear energy transfer particle strikes. Results are compared to muon experimental data taken at TRIUMF for validation. Rate predictions are made for the 28-nm SRAM using the calibrated model and compared to expected neutron rates. Muon-induced upset rates at sea level for both marginally reduced and significantly reduced electrical biases, as well as rates at 39 000 feet, are predicted to be significantly less than neutron rates in all these environments. This result is consistent with other authors’ efforts in similarly scaled bulk CMOS SRAMs, indicating that the modeling method used is reliable. [ABSTRACT FROM PUBLISHER]

Background: Clinical practice guidelines (CPGs) are widely used to inform the development of protocols for clinical management. Previous work has demonstrated that the quality of CPGs varies widely. This systematic review aimed to determine the quality of CPGs in kidney transplantation in the UK. Methods: CPGs in kidney transplantation published between 2010 and 2017 were identified through searches of MEDLINE, NHS NICE Evidence, and websites of relevant UK societies. Using the Appraisal of Guidelines for Research and Evaluation (AGREE) II tool, three appraisers rated the quality of CPGs across six domains, the overall quality of each CPG, and whether it should be recommended for future use. Domain scores were calculated, and inter‐rater reliability using the intraclass correlation coefficient (ICC) was reported. Results: Thirteen CPGs met the inclusion criteria. The domain ‘clarity of presentation’ scored highest, followed closely by ‘scope and purpose’. The poorest scoring domains were ‘applicability’ and ‘editorial independence’. Editorial independence also had the widest range of scores. Of the 13 CPGs, one was not recommended for future use, seven were recommended for use with modifications, and five for future use with no need for modification. Mean overall CPG quality was 5 (range 3–6) of a maximum score of 7, and mean inter‐rater reliability was substantial with an ICC of 0·71. Conclusion: UK CPGs scored satisfactorily, although with wide variation in how well each domain scored both within and across CPGs. The quality of UK CPGs can still be improved. [ABSTRACT FROM AUTHOR]

The impact of anthropogenic aerosol on climate forcing remains uncertain largely due to inadequate representation of natural aerosols in climate models. The marine boundary layer (MBL) might serve as a model location to study natural aerosol processes. Yet source and sink mechanisms controlling the MBL aerosol number, size distribution, chemical composition, and hygroscopic properties remain poorly constrained. Here aerosol size distribution and water uptake measurements were made aboard the R/V Hi'ialakai from 27 June to 3 July 2016 in the subtropical North Pacific Ocean. Size distributions were predominantly bimodal with an average integrated number concentration of 197 ± 98 cm−3. Hygroscopic growth factors were measured using the tandem differential mobility analyzer technique for dry 48, 96, and 144 nm particles. Mode kappa values for these were 0.57 ± 0.12, 0.51 ± 0.09, and 0.52 ± 0.08, respectively. To better understand remote MBL aerosol sources, a new algorithm was developed which decomposes hygroscopicity distributions into three classes: carbon-containing particles, sulfate-like particles, and sodium-containing particles. Results from this algorithm showed low and steady sodium-containing particle concentrations while the sulfate-like and carbon-containing particle concentrations varied during the cruise. According to the classification scheme, carbon-containing particles contributed at least 3-7%, sulfate-like particles contributed at most 77-88% and sodium-containing particles at least contributed 9-16% to the total aerosol number concentration. Size distribution and hygroscopicity data, in conjunction with air mass back trajectory analysis, suggested that the aerosol budget in the subtropical North Pacific MBL may be controlled by aerosol entrainment from the free troposphere. [ABSTRACT FROM AUTHOR]

Pure iron has been oxidized at 600 °C and 1 bar in dry O2 (oxygen partial pressure 0.05, bal. N2) and the mass gain as well as the thicknesses of the individual oxide phases have been measured. The oxidation process has been simulated using a modified version of the homogenization model as implemented in Dictra; this has helped to rationalize the kinetics of oxide scale formation and in particular the evolution of the hematite (Fe2O3), magnetite (Fe3O4), and wustite (FeO) which form. Independently assessed thermodynamic and kinetic Calphad databases are needed for the calculations; details of these are given. Reasonable agreement between simulation results and experimental data is obtained, though it is concluded that the large influence of grain boundary diffusion on the oxidation rate needs further consideration. [ABSTRACT FROM AUTHOR]

Aim Maintenance of the blood and extracellular volume requires tight control of endothelial macromolecule permeability, which is regulated by c AMP signalling. This study probes the role of the c AMP mediators rap guanine nucleotide exchange factor 3 and 4 (Epac1 and Epac2) for in vivo control of microvascular macromolecule permeability under basal conditions. Methods Epac1−/− and Epac2−/− C57 BL /6J mice were produced and compared with wild-type mice for transvascular flux of radio-labelled albumin in skin, adipose tissue, intestine, heart and skeletal muscle. The transvascular leakage was also studied by dynamic contrast-enhanced magnetic resonance imaging ( DCE- MRI) using the MRI contrast agent Gadomer-17 as probe. Results Epac1−/− mice had constitutively increased transvascular macromolecule transport, indicating Epac1-dependent restriction of baseline permeability. In addition, Epac1−/− mice showed little or no enhancement of vascular permeability in response to atrial natriuretic peptide ( ANP), whether probed with labelled albumin or Gadomer-17. Epac2−/− and wild-type mice had similar basal and ANP-stimulated clearances. Ultrastructure analysis revealed that Epac1−/− microvascular interendothelial junctions had constitutively less junctional complex. Conclusion Epac1 exerts a tonic inhibition of in vivo basal microvascular permeability. The loss of this tonic action increases baseline permeability, presumably by reducing the interendothelial permeability resistance. Part of the action of ANP to increase permeability in wild-type microvessels may involve inhibition of the basal Epac1-dependent activity. [ABSTRACT FROM AUTHOR]

Objectives The objective of this study was to evaluate possible nonlinear lamotrigine ( LTG) pharmacokinetics at elevated concentration. LTG is reported to have linear kinetics, so that elimination rate is linearly proportional to blood concentration and a change in dose is accompanied by a proportionate change in serum concentration. We encountered patients in whom LTG serum concentration increased dramatically in response to minor or no change in LTG dose. We studied this phenomenon in patients with LTG toxicity in one clinic. Materials and methods Using electronic medical records from 1997 to 2014, we identified patients who developed clinical LTG toxicity with LTG serum concentrations >20 mg/l, after tolerating lamotrigine at lower serum concentrations. We reviewed LTG dose change and other changes that preceded the episode of toxicity. Results Twenty-two patients had at least one episode of LTG toxicity with levels higher than 20 mg/l (of 922 patients with available levels). The peak serum concentration varied from 21.1 to 40.3 mg/l (mean 28.7). The increase in level was explained in three patients (post-delivery in one, addition of valproate in two). In the 18 others, the increase was not explained or it was disproportionate to an increase in LTG dose. Conclusions Spikes in LTG levels and associated clinical toxicity may occur unexpectedly, suggesting that elimination kinetics may be nonlinear in some individuals at serum concentrations in the upper range. Measurement and close monitoring of LTG levels is warranted for new symptoms that could be consistent with lamotrigine toxicity, particularly when the baseline serum concentration has been >10 mg/l. [ABSTRACT FROM AUTHOR]

A persistent loss-of-lock error was experimentally observed in a 20 nm charge-pump phase-locked loop (PLL). Through circuit modeling and simulation, the observed error was attributed to a non-recoverable off-state leakage increase resulted from two-photon absorption (TPA) laser-induced damage. The laser-induced damage is consistent with results from 28 nm bulk transistors. [ABSTRACT FROM PUBLISHER]

An in-situ testing method for high-temperature time-resolved surface observations inside the scanning electron microscope is described and used to improve the mechanistic understanding of a new polycrystalline nickel-based superalloy. The in-situ observations are able to elucidate surface mechanisms of damage in different deformation regimes. Tensile tests from ambient conditions to 750 °C determine the effect of temperature on the prevalent modes of deformation. At low and intermediate temperatures, the formation of discrete slip bands and the cracking of the harder precipitates (carbides) are observed directly. Under this regime, both inter- and trans-granular failure are observed. At the highest temperatures tested, the mechanism of damage is different; the grain boundaries, their orientation and their precipitates play a crucial role. Void growth is directly observed as a consequence of small hard-particle decohesion from the matrix, within those grain boundaries of relative orientation which promotes the shear deformation. As deformation increases, voids grow and coalesce, forming grain boundary cracks thus leading to catastrophic intergranular failure: this manifests itself as low-ductility particularly at the high-temperature conditions. [ABSTRACT FROM AUTHOR]