Thulium anomalies and rare earth element patterns in meteorites and Earth: Nebular fractionation and the nugget effect

This study reports the bulk rare earth element (REEs, La-Lu) compositions of 41 chondrites, including 32 falls and 9 finds from carbonaceous (CI, CM, CO and CV), enstatite (EH and EL) and ordinary (H, L and LL) groups, as well as 2 enstatite achondrites (aubrite). The CI-chondrite-normalized REE patterns and Eu anomalies in ordinary and enstatite chondrites show more scatter in more metamorphosed than in unequilibrated chondrites. This is due to parent-body redistribution of the REEs in various carrier phases during metamorphism. The dispersion in REE patterns of equilibrated ordinary chondrites is explained by the nugget effect associated with concentration of REEs in minor phosphate grains. Terrestrial rocks and samples from ordinary and enstatite chondrites display negative Tm anomalies of ~-4.5 % relative to ca chondrites. In contrast, CM, CO and CV (except Allende) show no significant Tm anomalies. Allende CV chondrite shows large excess Tm (~+10 %). These anomalies are similar to those found in group II refractory inclusions in meteorites but of much smaller magnitude. The presence of Tm anomalies in meteorites and terrestrial rocks suggests that either (i) the material in the inner part of the solar system was formed from a gas reservoir that had been depleted in refractory dust and carried positive Tm anomalies or (ii) CI chondrites are enriched in refractory dust and are not representative of solar composition for refractory elements. The observed Tm anomalies in ordinary and enstatite chondrites and terrestrial rocks, relative to carbonaceous chondrites, indicate that material akin to carbonaceous chondrites must have represented a small fraction of the constituents of the Earth.Comment: Geochimica et Cosmochimica Acta, in press, 58 pages, 6 tables, 14 figure

Tension pneumothorax, pneumoperitoneum, and cervical emphysema following a diagnostic colonoscopy

Colonoscopy is currently a widespread procedure used in screening for colorectal cancer. Iatrogenic colonic perforation during colonoscopy is a serious and potentially life-threatening complication that can cause significant morbidity and mortality. “Triple pneumo” (a combination of pneumothorax, pneumomediastinum, and pneumoperitoneum) following colonoscopy is a rare but a serious condition requiring immediate diagnosis and emergent intervention. In majority of these cases a colonic perforation is the initial injury that is followed by pneumothorax and pneumomediastinum through the potential anatomical connection with retroperitoneal and mediastinal spaces. In this rare case report we are presenting a case of “triple pneumo” with no evidence of colonic perforation. This patient developed a simultaneous pneumoperitoneum, pneumomediastinum, and a tension pneumothorax requiring immediate tube thoracostomy. This case may raise the awareness on the likelihood of these serious complications after colonoscopy

The Accuracy of Point-of-Care Ultrasound in Detecting Small Bowel Obstruction in Emergency Department

Radiological imaging plays an essential role in the evaluation of a patient with suspected small bowel obstruction (SBO). In a few studies, point-of-care ultrasound (POCUS) has been utilized as a primary imaging modality in patients with suspected SBO. POCUS has been shown to be an accurate tool in the diagnosis of SBO with multiple research studies noting a consistent high sensitivity with a range of 94–100% and specificity of 81–100%. Specific sonographic findings that increase the likelihood of SBO include dilatation of small bowel loops \u3e 25 mm, altered intestinal peristalsis, increased thickness of the bowel wall, and intraperitoneal fluid accumulation. Studies also reported that emergency physicians could apply this technique with limited and short-term ultrasound training. In this article, we aim to review the sensitivity and specificity of ultrasound examinations performed by emergency physicians in patients with suspected SBO

Early-Holocene greening of the Afro-Asian dust belt changed sources of mineral dust in West Asia

Production, transport and deposition of mineral dust have significant impacts on different components of the Earth systems through time and space. In modern times, dust plumes are associated with their source region(s) using satellite and land -based measurements and trajectory analysis of air masses through time. Reconstruction of past changes in the sources of mineral dust as related to changes in climate, however, must rely on the knowledge of the geochemical and mineralogical composition of modern and paleodust, and that of their potential source origins. In this contribution, we present a 13,000-yr record of variations in radiogenic Sr-Nd-Hf isotopes and Rare Earth Element (REE) anomalies as well as dust grain size from an ombrotrophic (rain fed) peat core in NW Iran as proxies of past changes in the sources of dust over the interior of West Asia. Our data shows that although the grain size of dust varies in a narrow range through the entire record, the geochemical fingerprint of dust particles deposited during the low flux, early Holocene period (11,700-6,000 yr BP) is distinctly different from aerosols deposited during high dust flux periods of the Younger Dryas and the mid-late Holocene (6,000-present). Our findings indicate that the composition of mineral dust deposited at the study site changed as a function of prevailing atmospheric circulation regimes and land exposure throughout the last deglacial period and the Holocene. Simulations of atmospheric circulation over the region show the Northern Hemisphere Summer Westerly Jet was displaced poleward across the study area during the early Holocene when Northern Hemisphere insolation was higher due to the Earth\u27s orbital configuration. This shift, coupled with lower dust emissions simulated based on greening of the Afro-Asian Dust Belt during the early Holocene likely led to potential sources in Central Asia dominating dust export to West Asia during this period. In contrast, the dominant western and southwest Asian and Eastern African sources have prevailed during the mid-Holocene to modern times. (C) 2017 Elsevier B.V. All rights reserved

A 28-ka history of sea surface temperature, primary productivity and planktonic community variability in the western Arabian Sea

Uranium series radionuclides and organic biomarkers, which represent major groups of planktonic organisms, were measured in western Arabian Sea sediments that span the past 28 ka. Variability in the past strength of the southwest and northeast monsoons and its influence on primary productivity, sea surface temperature (SST), and planktonic community structure were investigated. The average alkenone-derived SST for the last glacial period was similar to 3 degrees C lower than that measured for the Holocene. Prior to the deglacial, the lowest SSTs coincide with the highest measured fluxes of organic biomarkers, which represent primarily a planktonic suite of diatoms, coccolithophorids, dinoflagellates, and zooplankton. We propose that intensification of winter northeast monsoon winds during the last glacial period resulted in deep convective mixing, cold SSTs and enhanced primary productivity. In contrast, postdeglacial (\u3c 17 ka) SSTs are warmer during times in which biomarker fluxes are high. Associated with this transition is a planktonic community structure change, in which the ratio of the average cumulative flux of diatom biomarkers to the cumulative flux of coccolithophorid biomarkers is twice as high during the deglacial and Holocene than the average ratio during the last glacial period. We suggest that this temporal transition represents a shift from a winter northeast monsoon-dominated (pre-17 ka) to a summer southwest monsoon-dominated (post-17 ka) wind system

Comparing Three Data Mining Methods to Predict Kidney Transplant Survival

Introduction: One of the most important complications of post-transplant is rejection. Analyzing survival is one of the areas of medical prognosis and data mining, as an effective approach, has the capacity of analyzing and estimating outcomes in advance through discovering appropriate models among data. The present study aims at comparing the effectiveness of C5.0 algorithms, neural network and C & RTree to predict kidney transplant survival before transplant. Method: To detect factors effective in predicting transplant survival, information needs analysis was performed via a researcher-made questionnaire. A checklist was prepared and data of 513 kidney disease patient files were extracted from Sina Urology Research Center. Following CRISP methodology for data mining, IBM SPSS Modeler 14.2, C5.0, C&RTree algorithms and neural network were used. Results: Body Mass Index (BMI), cause of renal dysfunction and duration of dialysis were evaluated in all three models as the most effective factors in transplant survival. C5.0 algorithm with the highest validity (96.77) was the first in estimating kidney transplant survival in patients followed by C&RTree (83.7) and neural network (79.5) models. Conclusion: Among the three models, C5.0 algorithm was the top model with high validity that confirms its strength in predicting survival. The most effective kidney transplant survival factors were detected in this study; therefore, duration of transplant survival (year) can be determined considering the regulations set for a new sample with specific characteristics. © 2016 Leila Shahmoradi, Mostafa Langarizadeh, Gholamreza Pourmand, Ziba Aghsaei fard, and Alireza Borhani

Educational technology improves ECG interpretation of acute myocardial infarction for medical students and emergency medicine residents

Introduction: Asynchronous online training has become an increasingly popular educational format in the new era of technology-based professional development. We sought to evaluate the impact of an online asynchronous training module on the ability of medical students and emergency medicine (EM) residents to detect electrocardiogram (ECG) abnormalities of an acute myocardial infarction (AMI). Methods: We developed an online ECG training and testing module on AMI, with emphasis on recognizing ST elevation myocardial infarction (MI) and early activation of cardiac catheterization resources. Study participants included senior medical students and EM residents at all postgraduate levels rotating in our emergency department (ED). Participants were given a baseline set of ECGs for interpretation. This was followed by a brief interactive online training module on normal ECGs as well as abnormal ECGs representing an acute MI. Participants then underwent a post-test with a set of ECGs in which they had to interpret and decide appropriate intervention including catheterization lab activation. Results:148 students and 35 EM residents participated in this training in the 2012-2013 academic year. Students and EM residents showed significant improvements in recognizing ECG abnormalities after taking the asynchronous online training module. The mean score on the testing module for students improved from 5.9 (95% CI: [5.7-6.1]) to 7.3 (95% CI: [7.1-7.5]), with a mean difference of 1.4 (95% CI: [1.12-1.68]) (p Conclusion: An online interactive module of training improved the ability of medical students and EM residents to correctly recognize the ECG evidence of an acute MI. [West J Emerg Med.–0.

Loop-mediated isothermal amplification assay for identification of clinical Enterococcus species

Background: Enterococci are recognized as a cause of nosocomial infections and a major public health problem. The reliable identification to the species level of enterococci should be considered. Objectives: The study aimed to develop a LAMP assay for the rapid and accurate detection of Enterococcus faecalis and E. faecium. Methods: In total, 57 enterococcal isolates from UTI patients were identified using conventional microbiological methods. Two sets of specific primers were designed for E. faecalis and E. faecium targeting the mtlf and efmC genes, respectively. The LAMP assays were conducted using specific primers, dNTPs, MgSO4, Bst DNA polymerase, and templates. Results: The results of phenotypic testing indicated that of the 57 enterococcal isolates, 49 (85.9) were identified as E. faecalis and eight (14.1) as E. faecium. The optimal reaction temperatures in the LAMP assays were 60 and 61°C for the detection of E. faecalis and E. faecium, respectively. All the 57 enterococcal isolates were identified as E. faecalis by the LAMP assay. Conclusions: The present study highlights the importance of the LAMP assay as a rapid and confirmatory tool for the identification of clinical Enterococcus spp. © 2019, Archives of Clinical Infectious Diseases

A Comparison between Clinical and Pathologic Staging in Patients with Bladder Cancer

Purpose: To determine the accuracy of clinical staging methods of bladder cancer and TURBT results in estimating the pathologic stage of tumor.Materials and Methods: Thirty two patients who had undergone radical cystectomy were studied in this retrospective survey. The results of bimanual examination, cystoscopy, TURBT pathology report and the tumor contour in CT scan, (size, infiltrative deepness, pelvic lymph nodes involvement and hydronephrosis) were recorded. The type of surgery and pathologic report of cystectomy sample were analyzed as well. Then the results of bimanual examination, tumor size, hydronephrosis and CT scan findings including tumor infiltrative deepness, pelvic lymph adenopathy and TURBT findings were compared to pathologic results of cystectomy sample.Results: Seven patients were females and 25 were males. Their mean age was 62 (range 36 to 80) years. Gross hematuria and irritative urinary symptoms were the most common complaints. The duration between symptom manifestation and patient’s referral was 5 days to 72 months (mean 12 months). Bimanual examination in estimating the extravesical involvement of tumor had a specificity of 82%, sensitivity of 46%, positive predictive value of 70% and negative predictive value of 63%. The size of tumor in determining extravesical involvement had a specificity of 41%, sensitivity of 93%, and positive predictive value of 58% and negative predictive value of 87%. Hydronephrosis was present in 15 patients of whom, 14 (93%) had bladder muscle involvement. CT scan specificity was 70%, and sensitivity was 46% regarding pelvic lymph adenopathy and perivesical fat involvement. In TURBT report no muscle sample was observed in 11 cases, so that the interpretations of results were impossible. The reported grade of tumor was lower than pathologic sample of cystectomy in 4 patients.Conclusion: Clinical staging in invasive bladder cancers has not high accuracy regarding the involvement of bladder surrounding fats and pelvic adenopathies. A tumor sized more than 5 cm could be sensitive in estimating extravesical involvement. Positive predictive value of hydronephrosis is considerable regarding bladder muscle involvement. Tumor understaging by TURBT is happened in high percentage of patients with invasive bladder cancer.</p