The Analysis of Dynamic Processes of Virus Transmission: How Could Diagnostic Tests and Vaccinations Can Stop COVID-19 Pandemic?

Objectives: COVID-19 reached its fourth year of pandemic since 2020. The repeated waves of infections have been driven by multiple factors such as pathological traits of variants, diagnostic accuracy, and vaccination conditions. This study revisits and analyzes the dynamic processes of viral transmission to generate new scientific knowledge. Method(s): A cascade model of viral transmission from one case to another was developed, and theoretically analyzed how the number of infected cases at time t, D+[t], can be changed at time t+1, D+[t+1], considering six parameters: 1) k:level of transmission, 2) Rt: effective reproduction number, 3) rho: capture rate of infected cases, 4) theta: immunity protection rate in individuals, 5) epsilon: evasion rate from vaccines, and 6) Sn: test sensitivity. Result(s): The formula which associates D+[t] with D+[t+1] was given as follows: D+[t+1] = K.D+[t], where K = {(1-Sn) + (1-rho) / rho}{1-Rtk (1-theta(1-epsilon))k} / {1-Rt (1-theta(1-epsilon))}. Also, assuming K be smaller than 1, the lower limit of test sensitivity to stop the viral transmission was formulated: Sn > {Rt (1-theta(1-epsilon))-Rtk(1-theta(1-epsilon))k} / {(1-Rtk(1-theta(1-epsilon))k)rho}. In example computations, the formula indicated that a one-off PCR test with the sensitivity of 85% would not be sufficient to contain highly contagious infections such as the Omicron variants, and that it would be practically impossible to control the situation with the immune-evasive sub-variants in circulation. Conclusion(s): The theory developed in this study broadens the science on evidence-based public health and will be useful for outcomes studies and informed decisions on public policy for pandemic control.Copyright © 2023

Challenges and dilemmas of creative tourism in the 21st century: How can we preserve it from the massive offer?

Although there are not data to attest to the growth of various Creative Tourism experiences worldwide, the expectation of their increase is consistent with the strength of the nowadays markets and the strategies and changes needed to sustain this growth at the twenty-first century. So, it will be relevant to follow the new trends, changes and challenges that will shape the future path of Creative Tourism. In the context of the European Union, economic prosperity and well-being should respond to twin digital and green transitions that should prepare society to mitigate problems that arise from pandemic situations, such as the recent COVID-19. How do we follow new and future experiences, and how can institutions be positioned without jeopardising the massification of this segment? As with cultural tourism, this segment of creative initiatives can and should develop ways to avoid these possible mass derivations and adjust the preservation of its sustainability in the future. What strategy needs to be adapted so that future risks of vulgarisation will be avoided even within the possible new trends? What will be the role of the Southern European countries? This final chapter envisages promoting critical thinking about the role of Creative Tourism for local and regional development. The discussion focuses on how to prevent massification and how to respond to new challenges and saturated formulas and in accordance with the digital area of the twenty-first century. Also, it promotes some solutions based on short-term strategies to be outlined and on a TIN (Think, Integrate and Network) model, which can be replicated in many countries in Europe and in the rest of the world. © 2022 Paula Remoaldo, Vitor Ribeiro, Juliana Alves, Elaine Borges Scalabrini and Helder Lopes. All rights reserved.

Low-Dose Chest CT Protocols for Imaging COVID-19 Pneumonia: Technique Parameters and Radiation Dose.

Chest computed tomography (CT) plays a vital role in the early diagnosis, treatment, and follow-up of COVID-19 pneumonia during the pandemic. However, this raises concerns about excessive exposure to ionizing radiation. This study aimed to survey radiation doses in low-dose chest CT (LDCT) and ultra-low-dose chest CT (ULD) protocols used for imaging COVID-19 pneumonia relative to standard CT (STD) protocols so that the best possible practice and dose reduction techniques could be recommended. A total of 564 articles were identified by searching major scientific databases, including ISI Web of Science, Scopus, and PubMed. After evaluating the content and applying the inclusion criteria to technical factors and radiation dose metrics relevant to the LDCT protocols used for imaging COVID-19 patients, data from ten articles were extracted and analyzed. Technique factors that affect the application of LDCT and ULD are discussed, including tube current (mA), peak tube voltage (kVp), pitch factor, and iterative reconstruction (IR) algorithms. The CTDIvol values for the STD, LDCT, and ULD chest CT protocols ranged from 2.79-13.2 mGy, 0.90-4.40 mGy, and 0.20-0.28 mGy, respectively. The effective dose (ED) values for STD, LDCT, and ULD chest CT protocols ranged from 1.66-6.60 mSv, 0.50-0.80 mGy, and 0.39-0.64 mSv, respectively. Compared with the standard (STD), LDCT reduced the dose reduction by a factor of 2-4, whereas ULD reduced the dose reduction by a factor of 8-13. These dose reductions were achieved by applying scan parameters and techniques such as iterative reconstructions, ultra-long pitches, and fast spectral shaping with a tin filter. Using LDCT, the cumulative radiation dose of serial CT examinations during the acute period of COVID-19 may have been inferior or equivalent to that of conventional CT.

Analysis of the dynamic return and volatility connectedness for non-ferrous industrial metals during the COVID-19 pandemic crisis

PurposeThis paper aims to examine the dynamic return and volatility connectedness for six major industrial metals (tin, lead, nickel, zinc, copper and aluminium) and the coronavirus media coverage index (MCI).Design/methodology/approachTo that purpose, this study applies the fresh time-varying parameter vector autoregression methodology (TVP–VAR model) during the sample period between 2 January, 2020, and 16 April, 2021, that is, covering the three waves of the COVID-19 pandemic crisis.FindingsThis study's results show interesting findings. First, dynamic total return and volatility connectedness changes over time, highlighting a significant increase during the third wave of the pandemic. Second, the MCI index is a leading net transmitter in terms of return and volatility at the introduction of the SARS-CoV-2 coronavirus crisis. Third, this study clearly distinguishes two profiles among industrial metals: copper and tin/zinc as net transmitters and lead and aluminium as net receivers. Finally, the most relevant differences between them are concentrated not only at the beginning of the COVID-19 pandemic (first wave) but also during the second and third waves of the coronavirus outbreak.Originality/valueTo the best of the authors' knowledge, this is the first research that explores the dynamic return and volatility connectedness in the industrial metal market, applying the TVP–VAR methodology during the first waves of the COVID-19 pandemic crisis.

COVID-19 Chloroquine Drug Detection Using Novel, Highly Sensitive SnO2-Based Electrochemical Sensor

A highly sensitive, selective, stable, and cost-effective SnO2-based electrochemical sensor is reported for the detection of chloroquine phosphate (CQP). Hydrothermal synthesis is used to synthesize SnO2 nanoparticles, which are mixed with graphite and form a highly electrochemically active composite. The SnO2 nanoparticles and SnO2/graphite composite are fully characterized physico- and electrochemically. Using the optimal SnO2/graphite composite, an excellent analytical performance is demonstrated with an electrode sensitivity of 35.7 µA/µM.cm2, a linear range of 0.1-23.3 µM, and limits of detection and quantification of 0.01 µM and 0.04 µM, respectively. High CQP selectivity with minimal interference at 100 × concentration of interferents is shown. The sensor is also highly repeatable and reproducible with RSD of 2.46% and 1.86%, respectively, and can retain >85% of its activity upon storage. The validity of the new sensor for real sample analysis is shown by applying it to CQP tablets using the standard addition method, obtaining an excellent percentage recovery of ∼102%. The low cost, facile processing, and superior performance of the SnO2/graphite electrode make it an up-and-coming candidate for the commercial electrochemical detection of CQP and other small molecules.

A SARS-CoV-2 impedimetric biosensor based on the immobilization of ACE-2 receptor-containing entire cell membranes as the biorecognition element

A SARS-CoV-2 biosensor based on the biorecognition of the spike protein to the angiotensin-converting enzyme 2 (ACE-2) transmembrane receptor was developed using entire cell membranes as the biorecognition layer. In this new SARS-CoV-2 detection platform, cellular membranes from VeroCCL81 (mVero) and Calu-3 (mCalu) cells (which overexpress the ACE-2 transmembrane receptors) were extracted and immobilized as vesicles on an indium tin oxide electrode (ITO). Electrochemical impedance spectroscopy was used to optimize the performance of the developed devices for SARS-CoV-2 detection. This novel biosensor comprises a low-cost system (less than one US$ dollar) that uses the unique properties of cell membranes combined with the catalytic properties of electrochemical platforms to allow spike proteins recognition. A linear response from 10 to 100 ng/mL was obtained from the optimized biosensors, a limit of detection of 10.0 pg/mL and 7.25 pg/mL and limit of quantification of 30.4 pg/mL and 21.9 pg/mL were achieved with satisfactory accuracy for ITO-APTES-mVero and ITO-APTES-mCalu, respectively. Selectivity studies revealed that this platform was able to differentiate the target spike proteins from NS1 proteins from dengue and Zika viruses. In addition, sensors comprising cell membranes devoid of the ACE-2 transmembrane receptor exhibited no biorecognition signal. The developed devices are suitable for SARS-CoV-2 detection based on spike protein recognition, and capable of providing a low-cost, accurate, and accessible tool for use in a pandemic and post-pandemic scenario. [Display omitted] • Investigation on the interactions between natural cell membranes and Spike virus. • Influence of the ACE-2 receptors at the electrode surface to detect SARS-CoV-2. • Differentiation between SARS-CoV-2 from Dengue and Zika Virus using membrane cells elements. [ FROM AUTHOR]

Nafion Modified Titanium Nitride pH Sensor for Future Biomedical Applications.

pH sensors are increasingly being utilized in the biomedical field and have been implicated in health applications that aim to improve the monitoring and treatment of patients. In this work, a previously developed Titanium Nitride (TiN) solid-state pH sensor is further enhanced, with the potential to be used for pH regulation inside the human body and for other biomedical, industrial, and environmental applications. One of the main limitations of existing solid-state pH sensors is their reduced performance in high redox mediums. The potential shift E0 value of the previously developed TiN pH electrode in the presence of oxidizing or reducing agents is 30 mV. To minimize this redox shift, a Nafion-modified TiN electrode was developed, tested, and evaluated in various mediums. The Nafion-modified electrode has been shown to shift the E0 value by only 2 mV, providing increased accuracy in highly redox samples while maintaining acceptable reaction times. Overcoming the redox interference for pH measurement enables several advantages of the Nafion-modified TiN electrode over the standard pH glass electrode, implicating its use in medical diagnosis, real-time health monitoring, and further development of miniaturized smart sensors.

Oxidant- induced preconditioning: A pharmacologic approach for triggering renal 'self defense'.

Acute kidney injury (AKI) is a common event, occurring in ~5% and ~35% of hospitalized and ICU patients, respectively. The development of AKI portends an increased risk of morbidity, mortality, prolonged hospitalization, and subsequent development of chronic kidney disease (CKD). Given these facts, a multitude of experimental studies have addressed potential methods for inducing AKI prevention in high-risk patients. However, successful clinical translation of promising experimental data has remained elusive. Over the past decade, our laboratory has focused on developing a method for safely triggering AKI protection by inducing "kidney preconditioning" in mice by the intravenous administration of a combination of Fe sucrose (FeS) + tin protoporphyrin (SnPP). These agents induce mild, but short lived, 'oxidant stress' which synergistically activate a number of kidney 'self-defense' pathways (e.g., Nrf2, ferritin, IL-10). Within 18-24 h of Fe/SnPP administration, marked protection against diverse forms of experimental toxic and ischemic AKI results. FeS/SnPP-mediated reductions in kidney injury can also indirectly decrease injury in other organs by mitigating the so called "organ cross talk" phenomenon. Given these promising experimental data, three phase 1b clinical trials were undertaken in healthy subjects and patients with stage 3 or 4 CKD. These studies demonstrated that FeS/SnPP were well tolerated and that they up-regulated the cytoprotective Nrf2, ferritin, and IL-10 pathways. Two subsequent phase 2 trials, conducted in patients undergoing 'on-pump' cardiovascular surgery or in patients hospitalized with COVID 19, confirmed FeS/SnPP safety. Furthermore, interim data analyses revealed statistically significant improvements in several clinical parameters. The goals of this review are to: (i) briefly discuss the historical background of renal "preconditioning"; (ii) present the experimental data that support the concept of FeS/SnPP- induced organ protection; and (iii) discuss the initial results of clinical trials that suggest the potential clinical utility of an 'oxidant preconditioning' strategy.

A novel method development for classification of COVID-19 Pneumonia in lungs Using Machine learning approach

Artificial intelligence may be used to identify COVID-19 pneumonia (also known as pneumococcal meningitis) (AI). AI algorithms are also under scrutiny for their resilience and vulnerability, as are the datasets and research methods used to get the data. AI-driven COVID-19 pneumonia detectors that use our own data from retrospective clinical studies might help overcome these difficulties. In order to assess statistically the research designs, we optimized five deep learning architectures, applied development techniques by altering data distribution and introduced several detection scenarios to test the durability and diagnostic performance of the models. To a greater extent than the present data volume, detection model performance is influenced by hyper parameter adjustment. Sn, sp, and PPV are the three most important metrics in a two-class detection situation, and a method called InceptionV3 has the best of all three. It was shown that models had improved overall performance, with 91-96 percent Sn and 94-98 percent Sp and 91-96 PPV, compared to three-class detection results. Accuracy, F1 scores and g means are all higher than 96% accurate in InceptionV3, according to InceptionV3. For the identification of COVID-19 pneumonia, InceptionV3 had the greatest results, with an AUC of 99. An AUC of 0.98 distinguishes CoVID-19 pneumonia from other kinds of pneumonia, and a micro-average of 0.99 was achieved for the remaining classes.

BY THE WAY

After 21 years, he resigned and embarked on more than 100 cruises in 3 years, eventually Jg settling down after sailing on the largest cruise ship at the time in 2000. An 80-mile detour from the nearest interstate, the attraction features cars stacked up to mimic the famous British site. *Cabazon Dinosaurs: Cabazon, CA. Since 1975, this California roadside attraction has been home to more than 50 dinosaur friends, including Dinny the Dinosaur, a 150-ft brontosaurus that houses a museum in its belly. Built in 1881, this six-story example of novelty architecture is constructed of wood and tin sheeting.

New Tin(IV) Schiff base complexes: synthesis, characterization and antibacterial investigation, docking and theoretical studies

Organotin(IV) complexes with the formula [RSn(H2L)] (where R = Me (1), Ph (2) and n-Bu (3), H2L= 2,2'-((1E,1'E)-(naphthalene-1,8-diylbis(azanylylidene))bis(methanyl-ylidene))dibenzoic acid) have been produced via the reaction of organotin(IV) salts with H2L. Wholly the complexes have been studied via CHN analyses, FT-IR and UV–vis 1HNMR and mass spectral studies. The spectroscopic data of the ligand and its corresponding complexes (1-3) revealed that the Schiff base chelated to the tin metal ion in a bidentate manner through NN atoms (nitrogen atoms of azomethine group). Around tin atom, hexacoordinated geometry was exhibited. All the complexes were electrolytes except complex 2 is nonelectrolyte. Thermal decomposition of the complexes using thermogravimetric analysis under nitrogen showed that the thermal degradation of the complexes (1-3) occurred between 200-600 °C. The Schiff base tin(IV) complexes (1-3) were tested in vitro for their ability to suppress the growth of several bacteria strains. It was observed that the complexes were more effective at killing bacteria than the Schiff base ligand. Density functional calculations were performed to explain the structure and reactivity of the compounds. MOE 2008 was used headed for screen potential drugs with molecular docking by the protein sites of new coronavirus, Escherichia coli , Pseudomonas aeruginosa and crystal structure of MAOB. The study was constructed to molecular docking without validation through MD simulations.

Direct Sunlight Driven In2S3 Thin Film Based Water Treatment Proto-Type

A multi-faceted energy intensive technology that can be used for water disinfection and synthesis of electrolysed water (EW) is the need of the hour to achieve a sustainable post COVID 19 water management strategy. Direct sunlight driven processes are legislatively green technologies and hold the key in environmental sustenance. The development of a laboratory proto type reactor powered by a photovoltaic module for the treatment open source river water is described in this paper. This paper reports on the efficacy of the developed proto type technology for multipurpose application namely: (1) the production of Electrolysed water (EW) in a cost efficient manner using direct sunlight and (2) the removal of organic impurity from water using direct sunlight without the use of any photo catalyst or membrane. The prototype reactor utilizes chemical spray pyrolysis deposited highly photo-conducting indium sulphide thin films grown on fluorine doped tin oxide (F:SnO2) substrate (coated using chemical spray pyrolysis technique in-house) as the photo electrode. Dissolved organic matter arising in river water has distinctive fluorescence properties, and this research has utilized it to identify dissolved organic substances in both random samples and treated water. The work proves that photovoltaic module powered electrolytic reactors consisting of In2S3 electrodes can be used for treatment of river water. A diaphragm free, energy intensive route for the production of electrolysed water with the use of non-hazardous NaCl as the electrolyte has been demonstrated here. We conclude that In2S3 electrodes can be used for non-photo catalytic reduction of humic-derived impurities in river water. These results are also encouraging on the prospects of treating Nitrates present in the river water. The likes of techniques as described in this report that do not use photo catalyst or membranes may pave way for real time photovoltaic module powered floating reactors that can decontaminate water bodies on a large scale. The technique used by us demonstrates that a chlorine free route can be optimized for the synthesis of EW eliminating the production of large amounts of wastewater with high levels of biological oxygen demand (BOD).

Leaded or unleaded? Homemade microscale tin electroplating

Social distancing measures due to the SARS-CoV-2 virus have profoundly challenged the educational experimental work. We have sought to remediate this issue by designing a series of low cost, low risk, quick, and qualitative electrochemistry and corrosion experiments to be performed in the student's homes at the microscale with a kit provided by the teacher. One such experience is the electroplating of Sn from an aqueous chloride solution using readily available soldering wires (e.g., Sn-Pb alloy, or Sn-Ag-Cu alloy). This process catches students' attention due to its simplicity and variety of possible applications that include corrosion protection, fabrication of electronic components, plating of cooking utensils, lithium batteries, etc. © 2022 Maite R. Herrera-Loya et al., published by De Gruyter, Berlin/Boston 2022.

Severe Activity Of Inflammatory Bowel Disease Is A Risk Factor For Severe Covid-19: Data From The Sicilian Network For Inflammatory Bowel Disease (Sn-Ibd)

Background And Aim: Data From The First Wave Of Covid-19 Pan-Demic Suggested That Patients With Inflammatory Bowel Disease (Ibd) Are Not At Higher Risk Of Being Infected By Sars-Cov-2 Than The General Population And That, In Case Of Covid-19, Treatment With Immunomodulatory Drugs Is Not Associated With Worse Prognosis, With The Possible Exception Of Systemic Steroids. Evidence From The Second Wave Of Covid-19 Pandemic Is Required To Confirm These Findings. Materials And Methods: This Retrospective Observational Study Included Consecutive Ibd Patients Of The Cohort Of The Sicilian Network For Inflammatory Bowel Disease (Sn-Ibd) With Covid-19 Diagnosed By Pcr-Confirmed Presence Of Sars-Cov-2 Genome In A Nasopharyngeal Swab During The Second Covid-19 Pandemic Wave (15th September 2020–15th January 2020). Data Regarding Demo-Graphics, Ibd Features And Treatments, Comorbidities, And Symptoms Of Covid-19 Were Related To Covid-19 Clinical Outcomes. Results: One Hundred Twenty-Two Patients (Mean Age 43.9±16.7 Years;Males 50.0%;Crohn’S Disease 62.3%;Ulcerative Colitis: 37.7%) Were Included (Estimated Cumulative Incidence: 122/10,000 Ibd Patients=0.0122%). Twelve Patients Developed Covid-19-Related Pneumonia (9.8%), 4 (3.3%) Required Respiratory Assistance (Non-Mechanical Ventilation Or Orotracheal Intubation), And 4 Died (Case Fatality Rate: 3.3%). At Multivariate Analysis, Age (Or 1.034, 95% Ci 1.006-1.147, P=0.03) And Severe Ibd Activity (Or 13.465, 95% Ci 1.104-164.182, P=0.04) Were Independent Predictors Of Covid-19-Related Pneumonia, While Severe Ibd Activity (Or 15.359, 95% Ci 1.320-178.677, P=0.03) Was The Only Independent Predictor Of Severe Covid-19, A Composite End-Point Defined As Need For Respira-Tory Assistance And/Or Death. Concomitant Ibd Treatments Were Not Associated With Covid-19 Clinical Outcomes, Even If A Trend Toward A Protective Role Of Tnf-Inhibitors On Pneumonia Development Was Reported (P=0.08). Conclusions: In This Large Cohort Of Patients With Ibd And Covid-19, Severe Ibd Activity Was The Only Risk Factor For Severe Covid-19, While Ibd Treatments Were Not Associated With Worse Outcomes

Effect of TiO2 Concentration on Microstructure and Properties of Composite Cu-Sn-TiO2 Coatings Obtained by Electrodeposition.

In this work, Cu-Sn-TiO2 composite coatings were electrochemically obtained from a sulfate bath containing 0-10 g/L of TiO2 nanoparticles. The effect of TiO2 particles on kinetics of cathodic electrodeposition has been studied by linear sweep voltammetry and chronopotentiometry. As compared to the Cu-Sn alloy, the Cu-Sn-TiO2 composite coatings show rougher surfaces with TiO2 agglomerates embedded in the metal matrix. The highest average amount of included TiO2 is 1.7 wt.%, in the case of the bath containing 5 g/L thereof. Composite coatings showed significantly improved antibacterial properties towards E. coli ATCC 8739 bacteria as compared to the Cu-Sn coatings of the same composition. Such improvement has been connected with the corrosion resistance of the composites studied by linear polarization and electrochemical impedance spectroscopy. In the bacterial media and 3% NaCl solutions, Cu-Sn-TiO2 composite coatings have lower corrosion resistance as compared to Cu-Sn alloys, which is caused by the nonuniformity of the surface.