Measured electron contribution to Shuttle plasma environment: Abbreviated update

The differential energy spectra of electrons between 1 and 100 eV were measured by an electron spectrometer flown on an early shuttle. This energy range was scanned in 64 incremental steps with a resolution of 7%. The most striking feature that was observed throughout these spectra was a relatively flat distribution of the higher energy electrons out to 100 eV. This is in contrast to normal ambient spectra which consistently show a rapid decline in quantitative flux beyond 50 to 55 eV. The lower energy (1 to 2 eV) end of these spectra showed steep thermal trails comparable to normal ambient spectral structure. In general, daytime fluxes were significantly higher than those obtained during nighttime measurements. Quantitative flux excursions which may possibly be associated with thruster firing were frequently observed. Spectral structure suggestive of the N2 vibrational excitation energy loss mechanism was also seen in the data from some measurement periods. Examples of these spectra are shown and possible correlations are discussed

Carbon capture in the cement industry: technologies, progress, and retrofitting

Several different carbon-capture technologies have been proposed for use in the cement industry. This paper reviews their attributes, the progress that has been made toward their commercialization, and the major challenges facing their retrofitting to existing cement plants. A technology readiness level (TRL) scale for carbon capture in the cement industry is developed. For application at cement plants, partial oxy-fuel combustion, amine scrubbing, and calcium looping are the most developed (TRL 6 being the pilot system demonstrated in relevant environment), followed by direct capture (TRL 4–5 being the component and system validation at lab-scale in a relevant environment) and full oxy-fuel combustion (TRL 4 being the component and system validation at lab-scale in a lab environment). Our review suggests that advancing to TRL 7 (demonstration in plant environment) seems to be a challenge for the industry, representing a major step up from TRL 6. The important attributes that a cement plant must have to be “carbon-capture ready” for each capture technology selection is evaluated. Common requirements are space around the preheater and precalciner section, access to CO2 transport infrastructure, and a retrofittable preheater tower. Evidence from the electricity generation sector suggests that carbon capture readiness is not always cost-effective. The similar durations of cement-plant renovation and capture-plant construction suggests that synchronizing these two actions may save considerable time and money

Urate crystals induce macrophage PAF‑AH secretion which is differentially regulated by TGFβ1 and hydrocortisone

The aim of the present study was to establish the role of platelet‑activating factor acetyl hydrolase (PAF‑AH) in the resolution phase of gout using an established in vitro mononuclear cell model. The effects of signalling pathway inhibitors on PAF‑AH secretion, as well as the effects of the common treatments hydrocortisone and colchicine, an antibody against the anti‑inflammatory cytokine transforming growth factor β1 (TGFβ1), and the transcriptional inhibitor actinomycin D, were also investigated. The effect of recombinant PAF‑AH on cytokine secretion by these cells was also determined. Human peripheral blood‑derived monocytes were isolated and differentiated into macrophages. Monocytes and macrophages were stimulated with monosodium monohydrate urate (MSU) crystals or lipopolysaccharide in the presence or absence of AEG3482 [a c‑Jun N‑terminal kinase (JNK) inhibitor], MG132 (a proteasome inhibitor), hydrocortisone or colchicine. Cultures were then analysed for PAF‑AH secretion using ELISA. A 6‑fold upregulation of PAF‑AH secretion was observed following macrophage exposure to MSU crystals for 24 h (29.3±6 vs. 5.4±0.3 ng/ml unstimulated; P<0.05). Following 72 h, PAF‑AH levels decreased significantly (11.1±1.8; P<0.01). Secretion was further enhanced following pre‑treatment with the JNK protein kinase inhibitor AEG3482 prior to MSU crystal stimulation (P<0.05) and was abrogated when cells were preincubated with actinomycin D or the proteasome inhibitor MG132 (50, 100 and 200 µM). The addition of recombinant PAF‑AH (2.5‑10 ng/ml) to MSU crystal‑stimulated immature monocyte cultures significantly decreased pro‑inflammatory interleukin (IL)‑1β (unstimulated 687±124 vs. stimulated 113±30 pg/ml) and IL‑6 secretion (unstimulated 590±50 vs. stimulated 182±19 pg/ml). Treatment of MSU crystal‑stimulated macrophages with hydrocortisone (2 µM) also significantly decreased PAF‑AH release (P<0.05). Neutralising anti‑TGFβ1 addition decreased PAF‑AH dose‑dependently with the highest inhibition observed at 1 µg/ml (P<0.05). The results implicated that PAF‑AH may have an anti‑inflammatory role in the resolution phase of gout

Current-Voltage Characteristics of Weyl Semimetal Semiconducting Devices, Veselago Lenses and Hyperbolic Dirac Phase

The current-voltage characteristics of a new range of devices built around Weyl semimetals has been predicted using the Landauer formalism. The potential step and barrier have been reconsidered for a three-dimensional Weyl semimetals, with analogies to the two-dimensional material graphene and to optics. With the use of our results we also show how a Veselago lens can be made from Weyl semimetals, e.g. from NbAs and NbP. Such a lens may have many practical applications and can be used as a probing tip in a scanning tunneling microscope (STM). The ballistic character of Weyl fermion transport inside the semimetal tip, combined with the ideal focusing of the Weyl fermions (by Veselago lens) on the surface of the tip may create a very narrow electron beam from the tip to the surface of the studied material. With a Weyl semimetal probing tip the resolution of the present STMs can be improved significantly, and one may image not only individual atoms but also individual electron orbitals or chemical bonding and therewith to resolve the long-term issue of chemical and hydrogen bond formation. We show that applying a pressure to the Weyl semimental, having no centre of spacial inversion one may model matter at extreme conditions such as those arising in the vicinity of a black hole. As the materials Cd3As2 and Na3Bi show an asymmetry in their Dirac cones, a scaling factor was used to model this asymmetry. The scaling factor created additional regions of no propagation and condensed the appearance of resonances. We argue that under an external pressure there may arise a topological phase transition in Weyl semimetals, where the electron transport changes character and becomes anisotropic. There a hyperbolic Dirac phases occurs where there is a strong light absorption and photo-current generation

'Special K' and a loss of cell-to-cell adhesion in proximal tubule-derived epithelial cells: modulation of the adherens junction complex by ketamine

Ketamine, a mild hallucinogenic class C drug, is the fastest growing ‘party drug’ used by 16–24 year olds in the UK. As the recreational use of Ketamine increases we are beginning to see the signs of major renal and bladder complications. To date however, we know nothing of a role for Ketamine in modulating both structure and function of the human renal proximal tubule. In the current study we have used an established model cell line for human epithelial cells of the proximal tubule (HK2) to demonstrate that Ketamine evokes early changes in expression of proteins central to the adherens junction complex. Furthermore we use AFM single-cell force spectroscopy to assess if these changes functionally uncouple cells of the proximal tubule ahead of any overt loss in epithelial cell function. Our data suggests that Ketamine (24–48 hrs) produces gross changes in cell morphology and cytoskeletal architecture towards a fibrotic phenotype. These physical changes matched the concentration-dependent (0.1–1 mg/mL) cytotoxic effect of Ketamine and reflect a loss in expression of the key adherens junction proteins epithelial (E)- and neural (N)-cadherin and β-catenin. Down-regulation of protein expression does not involve the pro-fibrotic cytokine TGFβ, nor is it regulated by the usual increase in expression of Slug or Snail, the transcriptional regulators for E-cadherin. However, the loss in E-cadherin can be partially rescued pharmacologically by blocking p38 MAPK using SB203580. These data provide compelling evidence that Ketamine alters epithelial cell-to-cell adhesion and cell-coupling in the proximal kidney via a non-classical pro-fibrotic mechanism and the data provides the first indication that this illicit substance can have major implications on renal function. Understanding Ketamine-induced renal pathology may identify targets for future therapeutic intervention

The dynamical evolution of massive black hole binaries - I. Hardening in a fixed stellar background

The stellar ejection rate and the rates of change of the binary semimajor axis and eccentricity are derived from scattering experiments for the restricted three-body problem. They are used to study the evolution of binaries in simple models for galactic nuclei, starting soon after the black holes become bound and continuing until the evolution is dominated by the emission of gravitational radiation, or until the ejected mass is too large for the galaxy to be considered fixed. The eccentricity growth is found to be unimportant unless the binary forms with a large eccentricity. The scattering results are compared with predictions from Chandrasekhar's dynamical-friction formula and with previous work on the capture and scattering of comets by planetary systems. They suggest that a binary with masses $m_1\geq m_2$ should not be considered hard until its orbital velocity exceeds the background velocity dispersion by a factor that scales as $(1+m_1/m_2)^{1/2}$.Comment: includes 9 postscript figures, mn.sty, fixup.sty, psfig.st

Non-invasive assessment of pulmonary vascular resistance in pulmonary hypertension: Current knowledge and future direction

Pulmonary Hypertension (PHT) is relatively common, dangerous and under-recognised. Pulmonary hypertension is not a diagnosis in itself; it is caused by a number of differing diseases each with different treatments and prognoses. Therefore, timely and accurate recognition of the underlying cause for PHT is essential for appropriate management. This is especially true for patients with Pulmonary Arterial Hypertension (PAH) in the current era of disease-specific drug therapy. Measurement of Pulmonary Vascular Resistance (PVR) helps separate pre-capillary from post-capillary PHT, and is measured with right heart catheterisation (RHC). Echocardiography has been used to derive a number of non-invasive surrogates for PVR, with varying accuracy. Ultimately, the goal of non-invasive assessment of PVR is to separate PHT due to left heart disease from PHT due to increased PVR, to help streamline investigation and subsequent treatment. In this review, we summarise the physiology and pathophysiology of pulmonary blood flow, the various causes of pulmonary hypertension, and non-invasive surrogates for PVR

Atrial Fibrillation-Linked Germline GJA5/Connexin40 Mutants Showed an Increased Hemichannel Function

Mutations in GJA5 encoding the gap junction protein connexin40 (Cx40) have been linked to lone atrial fibrillation (AF). Some of these mutants result in impaired gap junction function due to either abnormal connexin localization or impaired gap junction channels, which may play a role in promoting AF. However, the effects of the AF-linked Cx40 mutants on hemichannel function has not been studied. Here we investigated two AF-linked germline Cx40 mutants, V85I and L221I. These two mutants formed putative gap junction plaques at cell-cell interfaces, with similar gap junction coupling conductance as that of wild-type Cx40. Connexin deficient HeLa cells expressing either of these two mutants displayed prominent propidium iodide (PI)-uptake distinct from cells expressing wild-type Cx40 or other AF-linked Cx40 mutants, I75F, L229M and Q49X. The PI-uptake was sensitive to [Ca2+]o and carbenoxolone, but was not affected by probenecid, indicating that uptake is mediated via connexin hemichannels. A gain-of-hemichannel function in these two AF-linked Cx40 mutants may provide a novel mechanism underlying the etiology of AF

The Recent Rise of Southern Banking

Between 1984 and 1986 the legislatures of several southern states enacted changes to their banking laws that enabled banking companies in Southern Region states to acquire and be acquired by banking companies in other Southern Region states, as long as these companies qualified as “Southern.” The purpose of the compact was to allow some southern banking companies an opportunity to grow and gain financial strength before full interstate banking was permitted. This study shows that the compact was successful. In 1985 no southern banking companies were among the top ten banks in the country, but by 2005 four were. Furthermore, no major southern bank has been acquired by a U.S. banking company outside of the South, although several southern banking companies have bought banks in other regions. The southern economy and its banking industry have benefited, although the benefits have been unevenly spread among states