Effect of tannin from rhizophora apiculate as corrosion inhibitor for epoxy paint on mild steel

There is a great concern to protect the steel surfaces from corrosion phenomenon in seawater environment. Several approaches have been proposed to introduce alternative new compounds in the paint which are green sources that can reduce environmental risks. The aim of this investigation was to enhance the protection properties of epoxy paint by providing an anticorrosive inhibitor for the paint. In this approach, the abilities of mangrove tannins, extracted from Rhizophora apiculata bark were studied. The inhibitive properties of mangrove tannins were evaluated by weight loss measurement, electrochemical impedance spectroscopy (EIS) and scanning electron microscope (SEM). Results shows the addition of mangrove tannin in the coating boosted the anticorrosive properties of the paint and represents valuable environmentally friendly of inhibitor

Bearing fault diagnosis employing gabor and augmented architecture of convolutional neural network

The vast impact on machinery that is rooted by bearing degradation thus pinpointing bearing fault diagnosis as indubitably very crucial. The research is innovated to diagnose the fault in bearing by implementing deep learning approach which is Convolutional Neural Network (CNN) that has superiority over image processing and pattern recognition. A novel model comprises of Gabor transform and augmented CNN is proposed whereby Gabor transform is utilized in representing the raw vibration signals into its 2D image representation, Gabor spectrogram. The augmented CNN is formed by alteration of the present CNN architecture. Gabor spectrogram are fed into the augmented CNN for training and testing in diagnosing the faults of bearings. To date, the method combination for bearing fault diagnosis application is inadequate. Plus, the usage of Gabor transform in mechanical area especially in bearing fault diagnosis is meagrely reported. At the end of the research, it is perceived that the proposed model comprises of Gabor transform and augmented CNN can diagnose the bearing faults with eminent accuracy and perform better than when CNN is fed with raw signals

Roll motion compensation by active marine gyrostabiliser

922-929Unmanned Surface Vehicle (USV) has been gaining more marine applications nowadays. However, the USV is vulnerable to excessive rolling motions induced by water waves, and this phenomenon may cause significant downtime to the operations of USV and engender detrimental effects to the on-board instrument and sensors. Active control system had been proposed to compensate the rolling stability issue but most of the proposed devices were expensive. This paper developed a gyrostabiliser on USV model to compensate the excessive rolling motion. Gyrostabiliser consists of rotor, gimbal and spinning axes, which commonly used for measuring or maintaining orientations and angular velocities. The gyrostabiliser was mounted vertically inside the USV model. Experiments were conducted to obtain the ideal gains of gyrostabiliser’s controller, to investigate the differences between active- and passive-gyrostabiliser, and to identify the induced pitch effect of the vertical gyrostabiliser to the USV model. The roll angle of the USV was measured by gyro sensor, whereas the precession motor and flywheel motor were controlled by a non-encoder Direct-Current (DC) motor. A proportional controller of the gyrostabiliser was implemented through Arduino Integrated Development Environment (IDE) to ensure optimal performance of gyrostabiliser in precession speed and direction control. The results showed that both active- and passive-gyrostabiliser managed to mitigate the roll angle of USV from +/- 15° back to less than 1° and reached steady state within 2.32 seconds and 2.60 seconds, respectively. The active gyrostabiliser had advantage to return to zero precession angle while the passive gyrostabiliser accumulated 30° precession angle in the experiment. The induced pitch angle by the gyrostabiliser had been found in an insignificant magnitude for the case study. The outcomes of this paper lead to an alternative for improving the robustness of USV in rolling reduction

Roll motion compensation by active marine gyrostabiliser

Unmanned Surface Vehicle (USV) has been gaining more marine applications nowadays. However, the USV is vulnerable to excessive rolling motions induced by water waves, and this phenomenon may cause significant downtime to the operations of USV and engender detrimental effects to the on-board instrument and sensors. Active control system had been proposed to compensate the rolling stability issue but most of the proposed devices were expensive. This paper developed a gyrostabiliser on USV model to compensate the excessive rolling motion. Gyrostabiliser consists of rotor, gimbal and spinning axes, which commonly used for measuring or maintaining orientations and angular velocities. The gyrostabiliser was mounted vertically inside the USV model. Experiments were conducted to obtain the ideal gains of gyrostabiliser’s controller, to investigate the differences between active- and passive-gyrostabiliser, and to identify the induced pitch effect of the vertical gyrostabiliser to the USV model. The roll angle of the USV was measured by gyro sensor, whereas the precession motor and flywheel motor were controlled by a non-encoder Direct-Current (DC) motor. A proportional controller of the gyrostabiliser was implemented through Arduino Integrated Development Environment (IDE) to ensure optimal performance of gyrostabiliser in precession speed and direction control. The results showed that both active- and passive-gyrostabiliser managed to mitigate the roll angle of USV from +/- 15° back to less than 1° and reached steady state within 2.32 seconds and 2.60 seconds, respectively. The active gyrostabiliser had advantage to return to zero precession angle while the passive gyrostabiliser accumulated 30° precession angle in the experiment. The induced pitch angle by the gyrostabiliser had been found in an insignificant magnitude for the case study. The outcomes of this paper lead to an alternative for improving the robustness of USV in rolling reduction. 

Procalcitonin Is Not a Reliable Biomarker of Bacterial Coinfection in People With Coronavirus Disease 2019 Undergoing Microbiological Investigation at the Time of Hospital Admission

Abstract Admission procalcitonin measurements and microbiology results were available for 1040 hospitalized adults with coronavirus disease 2019 (from 48 902 included in the International Severe Acute Respiratory and Emerging Infections Consortium World Health Organization Clinical Characterisation Protocol UK study). Although procalcitonin was higher in bacterial coinfection, this was neither clinically significant (median [IQR], 0.33 [0.11–1.70] ng/mL vs 0.24 [0.10–0.90] ng/mL) nor diagnostically useful (area under the receiver operating characteristic curve, 0.56 [95% confidence interval, .51–.60]).</jats:p

Implementation of corticosteroids in treating COVID-19 in the ISARIC WHO Clinical Characterisation Protocol UK:prospective observational cohort study

BACKGROUND: Dexamethasone was the first intervention proven to reduce mortality in patients with COVID-19 being treated in hospital. We aimed to evaluate the adoption of corticosteroids in the treatment of COVID-19 in the UK after the RECOVERY trial publication on June 16, 2020, and to identify discrepancies in care. METHODS: We did an audit of clinical implementation of corticosteroids in a prospective, observational, cohort study in 237 UK acute care hospitals between March 16, 2020, and April 14, 2021, restricted to patients aged 18 years or older with proven or high likelihood of COVID-19, who received supplementary oxygen. The primary outcome was administration of dexamethasone, prednisolone, hydrocortisone, or methylprednisolone. This study is registered with ISRCTN, ISRCTN66726260. FINDINGS: Between June 17, 2020, and April 14, 2021, 47 795 (75·2%) of 63 525 of patients on supplementary oxygen received corticosteroids, higher among patients requiring critical care than in those who received ward care (11 185 [86·6%] of 12 909 vs 36 415 [72·4%] of 50 278). Patients 50 years or older were significantly less likely to receive corticosteroids than those younger than 50 years (adjusted odds ratio 0·79 [95% CI 0·70–0·89], p=0·0001, for 70–79 years; 0·52 [0·46–0·58], p80 years), independent of patient demographics and illness severity. 84 (54·2%) of 155 pregnant women received corticosteroids. Rates of corticosteroid administration increased from 27·5% in the week before June 16, 2020, to 75–80% in January, 2021. INTERPRETATION: Implementation of corticosteroids into clinical practice in the UK for patients with COVID-19 has been successful, but not universal. Patients older than 70 years, independent of illness severity, chronic neurological disease, and dementia, were less likely to receive corticosteroids than those who were younger, as were pregnant women. This could reflect appropriate clinical decision making, but the possibility of inequitable access to life-saving care should be considered. FUNDING: UK National Institute for Health Research and UK Medical Research Council

A prenylated dsRNA sensor protects against severe COVID-19

Inherited genetic factors can influence the severity of COVID-19, but the molecular explanation underpinning a genetic association is often unclear. Intracellular antiviral defenses can inhibit the replication of viruses and reduce disease severity. To better understand the antiviral defenses relevant to COVID-19, we used interferon-stimulated gene (ISG) expression screening to reveal that OAS1, through RNase L, potently inhibits SARS-CoV-2. We show that a common splice-acceptor SNP (Rs10774671) governs whether people express prenylated OAS1 isoforms that are membrane-associated and sense specific regions of SARS-CoV-2 RNAs, or only express cytosolic, nonprenylated OAS1 that does not efficiently detect SARS-CoV-2. Importantly, in hospitalized patients, expression of prenylated OAS1 was associated with protection from severe COVID-19, suggesting this antiviral defense is a major component of a protective antiviral response

Para-infectious brain injury in COVID-19 persists at follow-up despite attenuated cytokine and autoantibody responses

To understand neurological complications of COVID-19 better both acutely and for recovery, we measured markers of brain injury, inflammatory mediators, and autoantibodies in 203 hospitalised participants; 111 with acute sera (1–11 days post-admission) and 92 convalescent sera (56 with COVID-19-associated neurological diagnoses). Here we show that compared to 60 uninfected controls, tTau, GFAP, NfL, and UCH-L1 are increased with COVID-19 infection at acute timepoints and NfL and GFAP are significantly higher in participants with neurological complications. Inflammatory mediators (IL-6, IL-12p40, HGF, M-CSF, CCL2, and IL-1RA) are associated with both altered consciousness and markers of brain injury. Autoantibodies are more common in COVID-19 than controls and some (including against MYL7, UCH-L1, and GRIN3B) are more frequent with altered consciousness. Additionally, convalescent participants with neurological complications show elevated GFAP and NfL, unrelated to attenuated systemic inflammatory mediators and to autoantibody responses. Overall, neurological complications of COVID-19 are associated with evidence of neuroglial injury in both acute and late disease and these correlate with dysregulated innate and adaptive immune responses acutely

Viral coinfections in hospitalized coronavirus disease 2019 patients recruited to the international severe acute respiratory and emerging infections consortium WHO clinical characterisation protocol UK study

Background We conducted this study to assess the prevalence of viral coinfection in a well characterized cohort of hospitalized coronavirus disease 2019 (COVID-19) patients and to investigate the impact of coinfection on disease severity. Methods Multiplex real-time polymerase chain reaction testing for endemic respiratory viruses was performed on upper respiratory tract samples from 1002 patients with COVID-19, aged <1 year to 102 years old, recruited to the International Severe Acute Respiratory and Emerging Infections Consortium WHO Clinical Characterisation Protocol UK study. Comprehensive demographic, clinical, and outcome data were collected prospectively up to 28 days post discharge. Results A coinfecting virus was detected in 20 (2.0%) participants. Multivariable analysis revealed no significant risk factors for coinfection, although this may be due to rarity of coinfection. Likewise, ordinal logistic regression analysis did not demonstrate a significant association between coinfection and increased disease severity. Conclusions Viral coinfection was rare among hospitalized COVID-19 patients in the United Kingdom during the first 18 months of the pandemic. With unbiased prospective sampling, we found no evidence of an association between viral coinfection and disease severity. Public health interventions disrupted normal seasonal transmission of respiratory viruses; relaxation of these measures mean it will be important to monitor the prevalence and impact of respiratory viral coinfections going forward