Analysis of alternative well control methods for dual density deepwater drilling

The recent push into deepwater is currently limited by high drilling costs resulting from conventional well designs. As a result, dual gradient drilling methods have been proposed. This research investigates riser gas-lift as a potential means to implement a dual gradient system. A primary concern is well control in a system containing so many different density fluids and different flow paths. The specific concerns addressed in this study were kick detection, cessation of formation feed-in, removal of kick fluids, and re-establishing hydrostatic control with a constant bottom hole pressure method. These concerns were studied using a transient, multiphase simulator whose validity was confirmed with comparison to transient, multiphase flow tests in a test well. Conventional kick detection methods relying on the pit gain and return flow rate were concluded to be effective. Two alternatives for stopping formation flow were considered, a “load-up†method of reducing the nitrogen rate versus closing a subsea BOP. BOP closure was shown to be more reliable for stopping flow and minimizing kick volume. Further, a relatively conventional approach of circulating up a gas-lifted choke line against a surface choke was compared to a dynamic approach based on reducing the nitrogen rate and to the use of a seafloor choke. It was concluded that methods using a choke were much simpler and more effective for controlling pressure than controlling the nitrogen rate. The subsea choke has an advantage over the surface choke due to faster pressure responsiveness, smaller pressure variation, and needing fewer and smaller choke adjustments

Named Entity Recognition -- Is there a glass ceiling?

Recent developments in Named Entity Recognition (NER) have resulted in better and better models. However, is there a glass ceiling? Do we know which types of errors are still hard or even impossible to correct? In this paper, we present a detailed analysis of the types of errors in state-of-the-art machine learning (ML) methods. Our study reveals the weak and strong points of the Stanford, CMU, FLAIR, ELMO and BERT models, as well as their shared limitations. We also introduce new techniques for improving annotation, for training processes and for checking a model's quality and stability. Presented results are based on the CoNLL 2003 data set for the English language. A new enriched semantic annotation of errors for this data set and new diagnostic data sets are attached in the supplementary materials.Comment: Accepted to CoNLL 201

Avian Influenza (H5N1) Virus in Waterfowl and Chickens, Central China

In 2004, 3 and 4 strains of avian influenza virus (subtype H5N1) were isolated from waterfowl and chickens, respectively, in central People’s Republic of China. Viral replication and pathogenicity were evaluated in chickens, quails, pigeons, and mice. We analyzed the sequences of the hemagglutinin and neuraminidase genes of the isolates and found broad diversity among them

The impact of adjuvant treatment with external beam radiotherapy and vaginal brachytherapy on health-related quality of life in patients with early-stage endometrioid endometrial carcinoma — initial results of a prospective study

Objectives: Our study evaluates the impact of adjuvant treatment with external beam radiotherapy (EBRT) combined with vaginal high-dose-rate brachytherapy (HDR BT) on health-related quality of life (HRQL) in patients with early-stage endometrioid endometrial carcinoma. Material and methods: We assessed HRQL of patients based on the EORTC QLQ-C30 questionnaire, with endometrial cancer specific HRQL module — EORTC QLQ-EN24. From March 2019 to April 2020 we enrolled 20 patients with early-stage endometrioid endometrial carcinoma, qualified for adjuvant treatment after hysterectomy. We compared the scores measured with the questionnaires at the beginning and at the end of the treatment. Results: There was a statistically significant decrease in the mean of global health status/quality of life assessed according to the EORTC QLQ-C30 scale, from 62.25 ± 13.12 at the beginning of the adjuvant radiotherapy to 55.85 ± 14.68 at the end of the treatment (p = 0.047). The mean appetite loss score was higher at the onset of the treatment as compared to its value after EBRT, 19.9 ± 27.33 vs 11.6 ± 19.52 (p = 0.043). Similarly to the mean constipation score, which was 29.85 ± 30.40 vs 11.6 ± 19.52 (p = 0.013). The mean diarrhoea symptom scale increased from 16.55 ± 20.16 to 56.75 ± 36.10 (p = 0.001). In the EORTC QLQ-EN24 scales, gastrointestinal symptoms scores were higher at the end of the treatment, (with the mean of 26.45 ± 22.76) as compared to 14.30 ± 16.52 at the beginning of EBRT (p = 0.003). Conclusions: Patients who receive adjuvant radiotherapy have decreased quality of life during the treatment reporting more serious gastrointestinal symptoms. The potential risk of treatment-related toxicity should be taken into account during the treatment planning process in order to minimize the deterioration of HRQL

Phylogenetic and Pathotypical Analysis of Two Virulent Newcastle Disease Viruses Isolated from Domestic Ducks in China

Two velogenic Newcastle disease viruses (NDV) obtained from outbreaks in domestic ducks in China were characterized in this study. Phylogenetic analysis revealed that both strains clustered with the class II viruses, with one phylogenetically close to the genotype VII NDVs and the other closer to genotype IX. The deduced amino acid sequence of the cleavage site of the fusion (F) protein confirmed that both isolates contained the virulent motif 112RRQK/RRF117 at the cleavage site. The two NDVs had severe pathogenicity in fully susceptible chickens, resulting in 100% mortality. One of the isolates also demonstrated some pathogenicity in domestic ducks. The present study suggests that more than one genotype of NDV circulates in domestic ducks in China and viral transmission may occur among chickens and domestic ducks

Avian influenza and avian paramyxoviruses in the New Zealand bird population : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Veterinary Virology at Massey University, Palmerston North, New Zealand

Content removed due to copyright restrictions: Stanislawek, W. L., Meers, J., Wilks, C., Horner, G. W., Morgan, C., & Alexander, D. J. (2001). A survey for paramyxoviruses in caged birds, wild birds, and poultry in new zealand. New Zealand Veterinary Journal, 49(1), 18-23. Stanislawek, W. L., Wilks, C. R., Meers, J., Horner, G. W., Alexander, D. J., Manvell, R. J., et al. (2002). Avian paramyxoviruses and influenza viruses isolated from mallard ducks (anas platyrhynchos) in new zealand. Archives of Virology, 147(7), 1287-1302.A comprehensive study using virological and serological approaches was carried out to determine the occurrence of avian paramyxoviruses (APMVs) and avian influenza viruses (AIVs) in live healthy mallard ducks (Anas platyrhynchos) in addition to caged birds, wild birds (other than waterfowl), and poultry. Thirty-three viruses were isolated from 321 tracheal and cloacal swabs from mallard ducks and were characterised as: 6 AIV (two H5N2 and four H4N6), 10 APMV-1, and 17 APMV-4. Of 335 serum samples tested for AIV antibodies, 109 (32.5%) sera were positive by nucleoprotein-blocking ELISA (NP-B-ELISA). Serum samples (315) were examined for antibody to APMV-1, -2, -3, -4, -6, -7, -8, and -9 by the haemagglutination inhibition (HI) test. The largest number of reactions, with titres up to ≥1/64, was to APMV-1 (93.1%), followed by APMV-6 (85.1%), APMV-8 (56%), APMV-4 (51.7%), APMV-7 (47%), APMV-9 (15.9%), APMV-2 (13.3%), and APMV-3 (6.0%). All of the H5N2 isolates of AIV and the APMV-1 isolates from this and earlier New Zealand studies had low pathogenicity indices when assessed by the Intravenous Pathogenicity Index (IVPI) with the result 0.00 and Intracerebral Pathogenicity Index (ICPI) with results 0.00-0.16. Partial genomic and antigenic analyses were also consistent with the isolates being non-pathogenic. Phylogenetic analysis of the 10 APMV-1 isolates showed nine to be most similar to the reference APMV-1 strain D26/76 originally isolated in Japan and also to the Que/66 strain, which was isolated in Australia. The other isolate was very similar to a virus (MC 110/77) obtained from a shelduck in France. Antibodies to APMV-1, -2, and -3 were detected in 4.8, 1.7, and 2.6%, respectively, of caged bird samples. The majority of these caged birds were "exotic" or "fancy" poultry breeds. Amongst wild birds, 4.2% had titres to APMV-2 and over half of these were passerine birds; 1.7% of the samples had titres to APMV-1 and 0.8% to APMV-3 antigen. No APMVs or AIVs were isolated from any of the cloacal swabs collected from these birds. Of the 1778 poultry serum samples tested only five reacted with APMV-3 antigen and these were later found to be cross-reactions to APMV-1. No reactions were detected with APMV-2 antigen. Although, we can be confident that APMV-1 is present in caged birds, wild birds, and poultry of New Zealand, there is no conclusive evidence of the presence of APMV-2 and APMV-3 in poultry or APMV-3 in wild birds. The results also do not provide conclusive evidence for the presence of APMV-2 in wild birds. Despite New Zealand being free from ND and highly pathogenic avian influenza (HPAI) in commercial poultry and the lack of evidence of pathogenic APMV-1 and AIVs in other birds, a number of possibilities were suggested by which virulent strains of APMV-1 and HPAI viruses could emerge in New Zealand including: (1) introduction by migratory birds; (2) importation of live birds and avian products: and (3) mutation in endemic viruses of low virulence. The findings from this study and elsewhere emphasise the importance of good biosecurity measures on poultry farms, to prevent the introduction of viruses of low virulence, as well as monitoring for the presence and type of APMV-1 and AIV in wild and domestic birds. The situation is likely to be dynamic with new strains emerging and the occurrence of clinically important introductions is a real possibility

Pyramidal ceramic armor ability to defeat projectile threat by changing its trajectory

This paper presents a numerical study of a multilayer composite panel impacted by an AP (Armor Piercing) 14.5×114 mm B32 projectile. The composite consists of alternating layers of hard ceramic and a ductile aluminum alloy. While the alloy layer consists of typical plate, ceramics confront projectiles in the form of ceramic pyramids. The studied models are compared with a reference structure, which is a standard double layer panel. The problem has been solved with the usage of modeling and simulation methods as well as a finite elements method implemented in LS-DYNA software. Space discretization for each option was built with three dimensional elements ensuring satisfying accuracy of the calculations. For material behavior simulation, specific models including the influence of the strain rate and temperature changes were considered. A steel projectile and aluminum plate material were described by the Johnson-Cook model and a ceramic target by the Johnson-Holmquist model. The obtained results indicate that examined structures can be utilized as a lightweight ballistic armor in certain conditions. However, panels consisting of sets of ceramic prisms are a little easier to penetrate. Despite this fact, a ceramic layer is much less susceptible to overall destruction, making it more applicable for the armor usage. What is most important in this study is that significant projectile trajectory deviation is detected, depending on the impact point. Such an effect may be utilized in solutions, where a target is situated relatively far from an armor

Influence of human body on Radio Signal Strength Indicator readings in indoor positioning systems

In this paper the basic assumptions of a Radio Signal Strength Indicator - based fingerprint and the influence of human body on the results are presented. The main focus is put on the influence of the obstruction of line-of-sight between access point and transceiver by a human body. This issue must be corrected in order to gain more accurate and reliable results of the positioning. The mathematical model for correction of this issue is proposed along with some examples. The examples are based on the real measurements made by authors. Presented correction formula allows to minimize the influence of the user - access point direction on the results obtained during fingerprint creation and positioning