Summary
Background
The recognition of eosinophilic oesophagitis (EoE) has risen sharply, but its current epidemiology is still under debate.
Aim
To estimate accurately the prevalence and incidence ...rates of EoE, by a systematic review and meta‐analysis.
Methods
MEDLINE, EMBASE and SCOPUS databases were searched for population‐based studies on the epidemiology of EoE. Pooled incidence and prevalence rates, male:female and children:adult ratios, and geographical and temporal variations were calculated with random‐effects models.
Results
The search yielded 1334 references; the final quantitative summary included 13 population‐based studies from North America, Europe and Australia, with the results showing high heterogeneity. The pooled EoE incidence rate was 3.7/100 000 persons/year 95% confidence interval (CI): 1.7–6.5 and was higher for adults (7; 95% CI: 1–18.3) than for children (5.1; 95% CI: 1.5–10.9).
The pooled prevalence of EoE was 22.7 cases/100 000 inhabitants (95% CI: 12.4–36), rising to 28.1 (95% CI: 13–49) when studies with a lower risk of bias were considered; prevalence was higher in adults than in children (43.4; 95% CI: 22.5–71.2 vs. 29.5; 95% CI: 17.5–44.7, respectively), and in American compared to European studies.
A steady rise in EoE incidence and prevalence rates was observed upon comparison of studies conducted before and after 2008. No significant publication bias was found.
Conclusions
Eosinophilic oesophagitis is an increasingly common diagnosis in North America and Europe. The population‐based incidence and prevalence of eosinophilic oesophagitis vary widely across individual studies, probably due to variations in diagnosis and risk of bias of research. More prospective, large‐scale, multicenter studies are needed to evaluate reported data.
Summary
Background
Conflicting results have been recently reported for the accuracy of the Endoscopic Reference Score (EREFS), an standardised endoscopic classification, to predict the histological ...activity of eosinophilic oesophagitis (EoE).
Aim
To evaluate the accuracy of the EREFS to predict either histological or clinical activity of EoE.
Methods
Prospective multicentre study conducted in eight Spanish centres evaluating adult EoE patients, either naïve or after treatment. Symptoms were evaluated before upper endoscopy through the Dysphagia Symptom Score, whereas researchers scored the EREFS immediately after the endoscopic procedure, unaware of the histological outcome.
Results
One hundred and forty‐five EoE patients undergoing 240 consecutive endoscopic procedures were included. Exudates (P = 0.03), furrows (P = 0.03) and a composite score of inflammatory signs (exudates, furrows and oedema) (P < 0.001) accurately predicted histological activity. Exudates were the only endoscopic sign showing a good correlation with histological outcome after therapy. Furrows and oedema persisted in 50% and 70% of patients despite histological remission. No endoscopic feature exceeded 70% accuracy to predict histological activity. Likewise, no endoscopic finding could adequately predict dysphagia severity. Crepe paper mucosa, diffuse exudates and severe rings correlated with higher symptom scores.
Conclusions
Endoscopic findings assessed by the Endoscopic Reference Score did not correlate with histological or clinical disease activity in adult EoE patients. Only exudates correlated with peak eosinophil count and histological outcome, whereas furrows and oedema persisted in over half of patients despite histological remission.
Summary
Rheumatoid arthritis is a disabling autoimmune disease with a high global prevalence. Treatment with disease‐modifying anti‐arthritic drugs (DIMARDs) has been routinely used with beneficial ...effects but with adverse long‐term consequences; novel targeted biologics and small‐molecule inhibitors are promising options. In this study, we investigated whether purified omega unsaturated fatty acids (ω‐UFAs) and dialysable leukocyte extracts (DLEs) prevented the development of arthritis in a model of collagen‐induced arthritis (CIA) in mice. We also investigated whether the transcription factor NF‐κB and the NLRP3 inflammasome were involved in the process and whether their activity was modulated by treatment. The development of arthritis was evaluated for 84 days following treatment with nothing, dexamethasone, DLEs, docosahexaenoic acid, arachidonic acid, and oleic acid. Progression of CIA was monitored by evaluating clinical manifestations, inflammatory changes, and histological alterations in the pads’ articular tissues. Both DLEs and ω‐UFAs led to an almost complete inhibition of the inflammatory histopathology of CIA and this was concomitant with the inhibition of NF‐kB and the inhibition of the activation of NLRP3. These data suggest that ω‐UFAs and DLEs might have NF‐κB as a common target and that they might be used as ancillary medicines in the treatment of arthritis.
The Villa de Reyes Graben has an aquifer system with intensive extraction that exploits millennial waters (Carrillo-Rivera et al., Appl Hydrogeol 1:35–48, 1992) . This research, through ...hydrogeochemical characterization and mixing models based on extreme members (hydrogeochemical data of major ions and conservative trace elements), was intended to establish the effect of intensive extraction and anthropogenic activity in the aquifer system with overexploitation and undermined condition. According to results, two water families were identified, which in order of abundance are Na–HCO
3
> Na–Mg–Ca–HCO
3
. The ionic exchange, silicate weathering, and mixing are the principal processes that take place in the aquifer. A mixing model methodology was applied to identify groundwater ternary mixtures consisting of an intermediate flow (
C
1
), a shallow water flow with an artificial recharge or irrigation return (
C
2
), and a regional thermal flow (
C
3
). The results of the mixing model show the contribution of each end member
C
1
(64.7%),
C
2
(8.1%), and
C
3
(7.2%) to the water system. Finally, the hydrogeochemical characterization shows that the recharge is almost zero. The intensive extraction of more evolved water has produced subsidence and faulting effects on the ground, decreased piezometric levels, and the pollution of shallow water. Therefore, decision-makers must consider these findings to manage and handle water resources in an area-undermining condition. It is expected that the results of this work will be considered for future decision-making in places with similar situations.
We analyse high-resolution, high-s/n European Southern Observatories (ESO)-archive spectra (from UVES, the UV echelle spectrograph) of 76 inactive or modestly active stars of spectral type G to M, ...main sequence and giants. Using phoenix model photospheres with Ca ii K lines that match the observed line profiles, we (i) revise the effective temperatures, (ii) obtain a precise surface flux scale for each star and (iii) directly determine the exact surface fluxes of each Ca ii K chromospheric emission with respect to the photospheric line profile. We find that our stellar sample exhibits a lower boundary to its chromospheric surface flux distribution with an unprecedented definition. From a subsample of the 25 least active stars, we obtain a simple empirical formula for the basal Ca ii flux as a function of effective temperature:
$\log {F^{\rm basal}_{\rm Ca\,\small {II}(H+K)}} = 7.05(\pm 0.31) \log {T_{\rm eff}} - 20.86(\pm 1.15)$
. This is in good agreement with the Mg ii basal flux. In a direct comparison with the large body of Mt Wilson S-measurements of the chromospheric Ca ii emission and its well-defined cut-off, excellent agreement is achieved as well. A new result, however, is the small scatter of the least active star's fluxes about the basal flux. It is about 25 per cent and equals the residual uncertainties of our approach. At the same time, we do not find any evidence for a gravity dependence within these limits. This strongly confirms the basal flux as a well-defined and universal phenomenon, which characterizes every inactive chromosphere.
Aims. We demonstrate the universal character of the quiet-Sun chromosphere among inactive stars (solar-type and giants). By assessing the main physical processes, we shed new light on some common ...observational phenomena. Methods. We discuss measurements of the solar Mt. Wilson S-index, obtained by the Hamburg Robotic Telescope around the extreme minimum year 2009, and compare the established chromospheric basal Ca II K line flux to the Mt. Wilson S-index data of inactive (“flat activity”) stars, including giants. Results. During the unusually deep and extended activity minimum of 2009, the Sun reached S-index values considerably lower than in any of its previously observed minima. In several brief periods, the Sun coincided exactly with the S-indices of inactive (“flat”, presumed Maunder Minimum-type) solar analogues of the Mt. Wilson sample; at the same time, the solar visible surface was also free of any plages or remaining weak activity regions. The corresponding minimum Ca II K flux of the quiet Sun and of the presumed Maunder Minimum-type stars in the Mt. Wilson sample are found to be identical to the corresponding Ca II K chromospheric basal flux limit. Conclusions. We conclude that the quiet-Sun chromosphere is a universal phenomenon among inactive stars. Its mixed-polarity magnetic field, generated by a local, “fast” turbulent dynamo finally provides a natural explanation for the minimal soft X-ray emission observed for inactive stars. Given such a local dynamo also works for giant chromospheres, albeit on longer length scales, i.e., l ∝ R/g, with R and g as stellar radius and surface gravity, respectively, the existence of giant spicular phenomena and the guidance of mechanical energy toward the acceleration zone of cool stellar winds along flux-tubes have now become traceable.
•The geothermal system has characteristics of a non-magmatic convective system of extensional domain.•The groundwater chemistry shows an evolution process according to the Chebotarev ...sequence.•Mixing, dilution, and exchange processes are taking place in the groundwater.•The temperature of reservoir was calculated by chemical geothermometers.
The objective of this study was preliminary reconnaissance of the Atotonilco el Alto-Santa Rita geothermal system in the northeastern Chapala graben in the state of Jalisco, Mexico. This was accomplished by evaluating the hydrogeochemical characteristics of the aquifer and the geological context. The study area is located in the western sector of the Neogene-Quaternary continental arc of the Trans-Mexican Volcanic Belt (TMVB). Hydrothermal deposits in the area consist of crusts, veinlets, stockwork, and replacements. Deposits and hydrothermal alterations are associated with minerals of montmorillonite, zeolites, opal, quartz, calcite, pyrite, romanechite, nontronite, and celadonite. Thirty water samples were collected from wells, springs, and a spa containing thermal- and cold-water discharges. The thermal water had a neutral to basic pH (7–8.6) with high electrical conductivity (EC) and total dissolved solids (TDSs) at 216–870 μS/cm and 142–575 mg/L. The cold water had a slightly acid to neutral pH (6–7) and higher ranges of EC and TDS than the thermal water (419–943 μS/cm and 277–623 mg/L, respectively), indicating a greater concentration of ions in solution. According to the water chemistry of the system, three water groups are present: shallow water with a predominant meteoric component, a mixture of different types of water, and thermal water. These water groups form a single system containing distinct hydrochemical facies. The Chebotarev sequence provides evidence of a groundwater evolution process where water passes through the lithological profile of the zone (alluvial deposits, conglomerates, and volcanic rock). Processes taking place within the aquifer include ion exchange, silicate weathering, mixing. An anomalous δ18O enrichment characteristic of the geothermal fluids is present in some thermal spring and well waters. The mineralogical results suggest the presence of a hydrothermal system with semi-neutral to alkaline characteristics of thermal fluids. The reservoir temperature was estimated using chemical geothermometry, which indicated that the hydrothermal system can be categorized as an intermediate-temperature system (between 80° and 160 °C). The Atotonilco el Alto-Santa Rita hydrothermal system has characteristics of a non-magmatic convective system of extensional domain, this extensional domain is due to the different rollback rates of the Cocos and Rivera plates, provoked by the northeastward directed toroidal mantle flow through the gap between the Rivera and Cocos slabs. The distribution of thermal manifestations is controlled by a NWSE system of faults and the crossing of ENE–WSW and E–W faults in which the Chapala graben originates. Finally, the heat source likely originates in the thinning of the Earth’s crust due to extensional tectonics.
This research work was conducted to characterize boride phases, obtained from the powder-pack process, on AISI H13 and D2 steel substrates, and investigate their tribological behavior. The boriding ...was developed at a temperature of 1273 K with an exposure time of 8 h. X-ray diffraction, scanning electron microscopy, and energy-dispersive X-ray spectroscopy were conducted on the borided material to characterize the presence of the FeB, Fe2B, and CrB phases and the distribution of heavy elements on the surface of the substrates. The adherence of the boride layers was evaluated, in a qualitative form, through the Daimler-Benz Rockwell-C indentation technique. Sliding wear tests were then performed using a reciprocating wear test machine. All tests were conducted in dry conditions at room temperature. A frequency of 10 Hz and 15-mm sliding distance were used. The applied Hertzian pressure was 2.01 GPa. Scanning electron microscopy was used to observe and analyze the wear mechanisms. Additionally, the variation of the friction coefficient versus the number of cycles was obtained. Experimental results showed that the characteristic wear mechanism for the borided surface was plastic deformation and mild abrasive wear; for unborided substrates, cracking and spalling were observed.
Phenyleneimine oligomers 4,4'-(((1E,1'E)-(((1E,1'E)-(1,4-phenylenebis-(azanylylidene))bis(methanylylidene))bis(2,5-bis(octyloxy)-4,1-phenylene))bis(methanylyl-idene))-bis(azanylylidene))dianiline ...(OIC1MS) and 7,7'-(((1E,1'E)-(((1E,1'E)-((9H-fluorene-2,7-diyl)bis(azanylylidene))bis(methanylylidene))bis(2,5-bis(octyloxy)-4,1phenylene))bis- (methanylylidene))bis(azanylylidene))bis(9H-fluoren-2-amine) (OIC2MS) were prepared by means of conventional and mechanochemical synthesis and characterized by FT-IR, 1H- and 13C-NMR techniques. The optical properties of the compounds were studied in solution by using UV-visible spectroscopy, and the optical effects were analyzed as a function of solvent. The results show that OIC2MS exhibits interesting photochromic properties. Furthermore, the structural and electronic properties of the compounds were analyzed by TD-DFT. It was found that the mechanosynthesis is an efficient method for the synthesis of both tetraimines.
The results of a sliding wear tests on base and thermal treated gray cast iron (GCI) samples from internal combustion engine cylinder liner are reported here for dry and lubricated conditions. A ...thermal treatment was applied to samples of 10 x 10 mm to avoid the effect of residual stress and to obtain the microstructure of interest. Tribological tests were carried out up to 27000 cycles at room temperature. A frequency of 15 Hz, a stroke amplitude of 6 mm, and a maximum contact pressure of 1.12 GPa were selected. Under the unlubricated settings, a noticeable decrease in friction coefficient and specific wear rate are attributed to the appearance of irregular graphite nodules in the heating-quenching process. The significance of thermal treatment applied to low carbon cast iron in the derived self-lubricating function and its synergistic role with the oil lubricant is discussed. In this context, this work illustrates, for the first time, how the change in the morphology from flake graphite to irregular nodule graphite positively determines the reliability of gray casting irons.
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