Evaluation and Improvement of Atmospheric Infrared Sounder (AIRS) Ice Cloud Retrievals

Clouds are still one of the largest uncertainties of the current climate models. While satellites provide suitable global datasets for comparing with cloud properties derived from models, satellite retrievals are inferences of cloud properties, rather than direct measurements, and therefore have errors. Therefore, it is important to evaluate satellite cloud products and gain advanced understanding of the products to accurately interpret the observations. This study investigates Aqua AIRS version 6 Level 2 cloud thermodynamic phase, ice cloud optical thickness, and ice cloud effective diameter, which released in April, 2013 and are available for all 13 years of the AIRS record. A filtering and gridding algorithm is used to create customized globally gridded datasets to evaluate the effects of satellite's viewing zenith angle, effective cloud fraction, cloud layers, cloud top temperature, time of the year, and geographic region. Viewing zenith angle does not strongly affect AIRS ice-phase, but higher viewing zenith angles lead to more water and fewer unknown pixels; the viewing zenith angle dependence is not strongly affected by the time of the year. Higher effective cloud fraction yields more ice- and water-phase, and less unknown-phase retrievals. Also, higher effective cloud fractions lead to greater values of ice cloud optical thickness. In addition, especially in high latitudes, ice-phase frequency is greater for two-layer clouds than single-layer clouds. On the other hand, water- and unknown-phase frequencies are greater for single layer clouds. Also, higher viewing zenith angles slightly decrease upper cloud top temperature. Approximately 90% of ice-phase cases have upper cloud top temperature values between 210 K and 235 K, ~80% of water-phase cases are found at 243-273 K upper cloud top temperature interval, and ~80% of the unknown cases have upper cloud top temperature values between 230 and 264 K. For ice cloud optical thickness and ice cloud effective diameter, no strong effects of satellite viewing zenith angle or cloud layering are observed

Magnetotransport study on AllnN/(GaN)/AIN/GaN heterostructures

Cataloged from PDF version of article.We report the effect of a thin GaN (2?nm) interlayer on the magnetotransport properties of AlInN/AlN/GaN-based heterostructures. Two samples were prepared (Sample A: AlInN/AlN/GaN and sample B: AlInN/GaN/AlN/GaN). Van der Pauw and Hall measurements were performed in the 1.9300?K temperature range. While the Hall mobilities were similar at room temperature (RT), sample B had nearly twice as large Hall mobility as sample A at the lowest temperature; 679 and 889?cm2/Vs at RT and 1460 and 3082?cm2/Vs at 1.9?K for samples A and B. At 1.910?K, the longitudinal magnetoresistance was measured up to 9?T, in turn revealing Shubnikovde Haas (SdH) oscillations. The carrier concentration, effective mass and quantum mobility of the two-dimensional electron gas (2DEG) were determined from SdH oscillations. At 1.9?K, the 2DEG concentration of sample B was nearly seven times larger than of sample A (1.67 x 10(13)/cm2 vs. 0.24 x 10(13)/cm2). On the contrary, the quantum mobility was changed adversely nearly three times (sample B 2500?cm2/Vs and sample A 970?cm2/Vs). The increase of the 2DEG concentration was attributed to the existence of the GaN interlayer, which has strengthened the spontaneous polarization difference between the AlInN and GaN layers of the heterostructure. Hence, the stronger electric field at the 2DEG region bent the conduction band profile downwards and consequently the quantum mobility decreased due to the increased interface roughness scattering

Fatigue analysis-based numerical design of stamping tools made of cast iron

This work concerns stress and fatigue analysis of stamping tools made of cast iron with an essentially pearlitic matrix and containing foundry defects. Our approach consists at first, in coupling the stamping numerical processing simulations and structure analysis in order to improve the tool stiffness geometry for minimizing the stress state and optimizing their fatigue lifetime. The method consists in simulating the stamping process by considering the tool as a perfect rigid body. The estimated contact pressure is then used as boundary condition for FEM structure loading analysis of the tool. The result of this analysis is compared with the critical stress limit depending on the automotive model. The acceptance of this test allows calculating the fatigue lifetime of the critical zone by using the S–N curve of corresponding load ratio. If the prescribed tool life requirements are not satisfied, then the critical region of the tool is redesigned and the whole simulation procedures are reactivated. This method is applied for a cast iron EN-GJS-600-3. The stress-failure (S–N) curves for this material is determined at room temperature under push pull loading with different load ratios R0σmin/σmax0−2, R0−1 and R00.1. The effects of the foundry defects are determined by SEM observations of crack initiation sites. Their presence in tested specimens is associated with a reduction of fatigue lifetime by a factor of 2. However, the effect of the load ratio is more important

Circulating intercellular adhesion molecule-1 and E-selectin levels in gastric cancer.

A diversity of adhesive interactions occur between the cancer cell and host extracellular matrix which potentiate neoplastic expansion and metastatic dissemination. In miscellaneous malignant diseases, tumour progression has been observed to be associated with alterations in adhesion molecule expression. Recently, circulating soluble intercellular adhesion molecules have been identified. In this study, serum levels of soluble intercellular adhesion molecule-1 (sICAM-1) and soluble E-selectin (sE-selectin) were determined in patients with gastric cancer. The study group consisted of 27 patients with previously untreated gastric adenocarcinoma. Four patients had stage II, two patients stage III and 21 patients stage IV disease according to the TNM classification. Nineteen patients had distant metastasis. The sera obtained from 18 healthy volunteers served as controls. Serum sICAM-1 and sE-selectin concentrations were determined by enzyme-linked immunosorbent assay (ELISA). In addition, we also studied other tumour-associated antigens, i.e. CEA and CA 19-9. Serum sICAM-1 levels were significantly increased in patients with gastric cancer (P < 0.0001). However, sE-selectin levels did not differ from the controls. sICAM-1 concentrations were also significantly higher in patients with distant metastasis and peritoneal spread (P = 0.0045 and P = 0.0157 respectively), whereas sE-Selectin levels were elevated only in patients with peritoneal metastasis (P = 0.033). Serum concentrations of sICAM-1 and sE-selectin correlated with CEA levels (P = 0.0013 and P = 0.003 respectively). Elevated levels of sE-selectin were associated with poorer prognosis (P = 0.0099), whereas sICAM-1 had no significant impact on survival. Our results suggest that increased sICAM-1 serum levels may reflect widespread disease and contribute directly to the progression of gastric cancer. Further investigation of the molecular mechanisms of adhesive tumour-host interactions may lead to a better understanding of the natural history of gastric cancer

Right atrial pathology in arrhythmogenic right ventricular dysplasia

Background: Atrial fibrillation (AF) is the most common atrial arrhythmia in arrhythmogenic right ventricular cardiomyopathy/dysplasia (ARVD). Considering the histologic changes known in the right ventricular (RV) in ARVD, the aim of the present study was to examine right atrial (RA) pathology in patients with ARVD. Methods: Histology of RA and RV was assessed from autopsy material in 3 patients with ARVD without persistent atrial arrhythmia. RA histology in 3 patients with permanent AF without ARVD and 5 patients without cardiovascular disease was also studied. Staining with hematoxylin phloxine saffron was performed for the ARVD patients to identify fibrosis, and hematoxylin-eosin for identification of lymphocytes. Masson’s trichrome staining was performed for control groups taken from a collection of standard glass slides. Results: In all 3 ARVD cases, RA anomalies were observed that revealed a reduction of cardiomyocytes, the presence of adipocytes, some of them inside the mediomural atrial layer and interstitial fibrosis. In 2 ARVD cases, interstitial fibrosis was also associated with a focus of replacement fibrosis, which was also observed in patients with permanent AF without ARVD. The histologic specimen of the RA and RV from the control group without cardiovascular disease did not display any evidence of fat or fibrosis with a preserved cardiomyocyte architecture. Conclusions: A similar histopathological substrate, as can be observed in the RV of patients with ARVD can also be seen in the RA of these patients. This may explain the high prevalence of atrial arrhythmias, particularly AF, in patients with ARVD

Ultrasonic Spray Pyrolysis Deposited Copper Sulphide Thin Films for Solar Cell Applications

Polycrystalline copper sulphide (CuxS) thin films were grown by ultrasonic spray pyrolysis method using aqueous solutions of copper chloride and thiourea without any complexing agent at various substrate temperatures of 240, 280, and 320°C. The films were characterized for their structural, optical, and electrical properties by X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive analysis of X-rays (EDAX), atomic force microscopy (AFM), contact angle (CA), optical absorption, and current-voltage (I-V) measurements. The XRD analysis showed that the films had single or mixed phase polycrystalline nature with a hexagonal covellite and cubic digenite structure. The crystalline phase of the films changed depending on the substrate temperature. The optical band gaps (Eg) of thin films were 2.07 eV (CuS), 2.50 eV (Cu1.765S), and 2.28 eV (Cu1.765S–Cu2S). AFM results indicated that the films had spherical nanosized particles well adhered to the substrate. Contact angle measurements showed that the thin films had hydrophobic nature. Hall effect measurements of all the deposited CuxS thin films demonstrated them to be of p-type conductivity, and the current-voltage (I-V) dark curves exhibited linear variation

Atrial fibrillation and treatment changes in cryptogenic stroke patients with an implantable loop recorder for continuous cardiac rhythm monitoring

Introduction: This interim analysis evaluates the risk profile and incidence of atrial fibrillation (AF) in patients who underwent continuous monitoring with an implantable loop recorder (ILR) for cryptogenic (unexplained) stroke or transient ischemic attack (TIA). Methods: The observational INSIGHT XT study prospectively enrolled patients who received an ILR with dedicated diagnostics for atrial fibrillation, irrespective of the clinical indication. Of 1002 patients enrolled in the study between Aug 2008 and Jan 2012, 121 received the ILR to evaluate cryptogenic stroke or TIA. The definition of cryptogenic stroke/TIA was at the investigators' appraisal and no unified approach to patient work-up was required. This analysis includes 74 patients with cryptogenic stroke or TIA for whom at least one follow-up visit was available at the time of interim analysis. Results: The mean age was 63±12 (50% female). Stroke was the index event in 46 of 74 (62%) of patients. 61% had hypertension, 14% diabetes, and none had heart failure. The mean CHADS2 score was 3.0±0.8 and the mean CHA2DS2VASc score 4.0±1.2. Most patients (72%) had no prior symptoms or cardiac rhythm disturbances, whereas 18% had a history of prior palpitations. Sixty-seven patients were taking antiplatelet medication and four were on oral anticoagulation (OAC) at enrollment. During a median follow up of 12 months (IQR 7 to 18) AF was reported in 17 patients (23%) and two patients were started on OAC and 10 patients were converted from antiplatelets to OAC. Five patients experienced a stroke or TIA (median time to event 1.2 months), of which one patient died. Three of the patients with stroke or TIA had AF detected prior to the recurrent event. Conclusion: Continuous monitoring with an ILR in patients with cryptogenic stroke of TIA detects a high proportion of AF; this can be attributed to longer continuous monitoring in this study. These patients have high CHADS2/CHA2DS2VASc scores; documenting AF in these cases may therefore be clinically relevant in order to decide appropriate treatment

The Devil is in the Errors: Leveraging Large Language Models for Fine-grained Machine Translation Evaluation

Automatic evaluation of machine translation (MT) is a critical tool driving the rapid iterative development of MT systems. While considerable progress has been made on estimating a single scalar quality score, current metrics lack the informativeness of more detailed schemes that annotate individual errors, such as Multidimensional Quality Metrics (MQM). In this paper, we help fill this gap by proposing AutoMQM, a prompting technique which leverages the reasoning and in-context learning capabilities of large language models (LLMs) and asks them to identify and categorize errors in translations. We start by evaluating recent LLMs, such as PaLM and PaLM-2, through simple score prediction prompting, and we study the impact of labeled data through in-context learning and finetuning. We then evaluate AutoMQM with PaLM-2 models, and we find that it improves performance compared to just prompting for scores (with particularly large gains for larger models) while providing interpretability through error spans that align with human annotations.Comment: 19 page