Twelve-month observational study of children with cancer in 41 countries during the COVID-19 pandemic

Introduction Childhood cancer is a leading cause of death. It is unclear whether the COVID-19 pandemic has impacted childhood cancer mortality. In this study, we aimed to establish all-cause mortality rates for childhood cancers during the COVID-19 pandemic and determine the factors associated with mortality. Methods Prospective cohort study in 109 institutions in 41 countries. Inclusion criteria: children <18 years who were newly diagnosed with or undergoing active treatment for acute lymphoblastic leukaemia, non-Hodgkin's lymphoma, Hodgkin lymphoma, retinoblastoma, Wilms tumour, glioma, osteosarcoma, Ewing sarcoma, rhabdomyosarcoma, medulloblastoma and neuroblastoma. Of 2327 cases, 2118 patients were included in the study. The primary outcome measure was all-cause mortality at 30 days, 90 days and 12 months. Results All-cause mortality was 3.4% (n=71/2084) at 30-day follow-up, 5.7% (n=113/1969) at 90-day follow-up and 13.0% (n=206/1581) at 12-month follow-up. The median time from diagnosis to multidisciplinary team (MDT) plan was longest in low-income countries (7 days, IQR 3-11). Multivariable analysis revealed several factors associated with 12-month mortality, including low-income (OR 6.99 (95% CI 2.49 to 19.68); p<0.001), lower middle income (OR 3.32 (95% CI 1.96 to 5.61); p<0.001) and upper middle income (OR 3.49 (95% CI 2.02 to 6.03); p<0.001) country status and chemotherapy (OR 0.55 (95% CI 0.36 to 0.86); p=0.008) and immunotherapy (OR 0.27 (95% CI 0.08 to 0.91); p=0.035) within 30 days from MDT plan. Multivariable analysis revealed laboratory-confirmed SARS-CoV-2 infection (OR 5.33 (95% CI 1.19 to 23.84); p=0.029) was associated with 30-day mortality. Conclusions Children with cancer are more likely to die within 30 days if infected with SARS-CoV-2. However, timely treatment reduced odds of death. This report provides crucial information to balance the benefits of providing anticancer therapy against the risks of SARS-CoV-2 infection in children with cancer

Prognostic model to predict postoperative acute kidney injury in patients undergoing major gastrointestinal surgery based on a national prospective observational cohort study.

Background: Acute illness, existing co-morbidities and surgical stress response can all contribute to postoperative acute kidney injury (AKI) in patients undergoing major gastrointestinal surgery. The aim of this study was prospectively to develop a pragmatic prognostic model to stratify patients according to risk of developing AKI after major gastrointestinal surgery. Methods: This prospective multicentre cohort study included consecutive adults undergoing elective or emergency gastrointestinal resection, liver resection or stoma reversal in 2-week blocks over a continuous 3-month period. The primary outcome was the rate of AKI within 7 days of surgery. Bootstrap stability was used to select clinically plausible risk factors into the model. Internal model validation was carried out by bootstrap validation. Results: A total of 4544 patients were included across 173 centres in the UK and Ireland. The overall rate of AKI was 14·2 per cent (646 of 4544) and the 30-day mortality rate was 1·8 per cent (84 of 4544). Stage 1 AKI was significantly associated with 30-day mortality (unadjusted odds ratio 7·61, 95 per cent c.i. 4·49 to 12·90; P < 0·001), with increasing odds of death with each AKI stage. Six variables were selected for inclusion in the prognostic model: age, sex, ASA grade, preoperative estimated glomerular filtration rate, planned open surgery and preoperative use of either an angiotensin-converting enzyme inhibitor or an angiotensin receptor blocker. Internal validation demonstrated good model discrimination (c-statistic 0·65). Discussion: Following major gastrointestinal surgery, AKI occurred in one in seven patients. This preoperative prognostic model identified patients at high risk of postoperative AKI. Validation in an independent data set is required to ensure generalizability

Design Simulation and Data Analysis of an Optical Spectrometer

Spectrometers have a wide range of applications ranging from optical to non-optical spectroscopy. The need for compact, portable, and user-friendly spectrometers has been a focus of attention from small laboratories to the industrial scale. Here, the Czerny Turner configuration-based optical spectrometer simulation design was carried out using ZEMAX OpticStudio. A compact and low-cost optical spectrometer in the visible range was developed by using diffraction grating as a dispersive element and a USB-type webcam CCD (charge-coupled device) as a detector instead of an expensive commercial diffraction grating and detector. Using National Instruments LabVIEW, data acquisition, processing, and display techniques were made possible. We employed different virtual images in LabVIEW programs to collect the pixel-to-pixel information and wavelength-intensity information from the image captured using the webcam CCD. Finally, we demonstrated that the OpticStudio-based spectrometer and experimental measurements with the developed spectrometer were in good agreement

Design, Construction and Characterization of Sealed Tube Medium Power CO2 Laser System

A low-cost medium-power carbon dioxide (CO2) laser system is designed, constructed, and characterized to produce coherent, monochromatic laser radiation in the infrared region. The laser cavity is simulated and designed by using ZEMAX optic studio. A switch-mode high-tension pump source is designed and constructed using a flyback transformer and simulated using NI Multisim to study the voltage behavior at different node points. A prototype cooling system/chiller is designed and built using thermo-electric coolers (TEC) to remove the excess heat produced during laser action. Various parameters, such as pumping mechanism, chiller stability, efficiency, output power, and current at different applied voltages, are studied. The chiller efficiency at different output powers of the laser is analyzed, which clearly shows that the chiller&rsquo;s cooling rate is good enough to compensate for the heat generated by the laser system. The center wavelength of the carbon dioxide laser is 10.6 &mu;m with an FWHM of 1.2 nm simulated in the ZEMAX optic studio. The output beam penetration through salt rock (NaCl), wood, and acrylic sheet (PMMA) at various output powers is analyzed to measure the penetration depth rate of the CO2 laser

Design Simulation and Data Analysis of an Optical Spectrometer

Spectrometers have a wide range of applications ranging from optical to non-optical spectroscopy. The need for compact, portable, and user-friendly spectrometers has been a focus of attention from small laboratories to the industrial scale. Here, the Czerny Turner configuration-based optical spectrometer simulation design was carried out using ZEMAX OpticStudio. A compact and low-cost optical spectrometer in the visible range was developed by using diffraction grating as a dispersive element and a USB-type webcam CCD (charge-coupled device) as a detector instead of an expensive commercial diffraction grating and detector. Using National Instruments LabVIEW, data acquisition, processing, and display techniques were made possible. We employed different virtual images in LabVIEW programs to collect the pixel-to-pixel information and wavelength-intensity information from the image captured using the webcam CCD. Finally, we demonstrated that the OpticStudio-based spectrometer and experimental measurements with the developed spectrometer were in good agreement

Synthesis, photochemical and electrochemical studies on triphenyltin(IV) derivative of (Z)-4-(4-cyanophenylamino)-4-oxobut-2-enoic acid for its binding with DNA: Biological interpretation

(Z)-4-(4-cyanophenylamino)-4-oxobut-2-enoic acid (LH) and its new triphenyltin (IV) derivative (Ph3SnL) were synthesized and further investigated for their binding with ds.DNA under physiological conditions {pH: 4.7 (stomach); 7.4 (blood), 37 °C} using UV–Visible/fluorescence spectroscopy, cyclic voltammetry and viscosity measurement techniques. Spectral responses as well as experimental findings from all the techniques i.e., binding constant (Kb), binding site size (n) and free energy change (ΔG) correlated with each other and indicated formation of spontaneous compound–DNA complexes via intercalation of compounds into the DNA base pairs. Values of kinetic parameter, Kb, revealed comparatively greater binding of both the compounds with DNA at stomach pH (4.7). However among both compounds organotin complex (Ph3SnL) showed comparatively greater binding than that of its ligand (LH) as evident from its, Kb, values at both the pH values. In general, Kb values were evaluated greater for Ph3SnL at stomach pH {: Kb: 8.65 × 104 M−1 (UV); 5.49 × 104 M−1 (fluorescence); 8.85 × 104 M−1 (CV)}. Voltammetric responses of both compounds before and after the addition of DNA indicated that diffusion controlled processes are involved. Complex Ph3SnL exhibited the best antitumor activity

Fabrication of Highly Catalytically Active Gold Nanostructures on Filter-Paper and Their Applications towards Degradation of Environmental Pollutants

Supported metallic nanoparticles (NPs) have recently become a promising candidate for the degradation of environmental pollutants. In this work, we report the fabrication of highly catalytically active, surfactant-free interconnected Au nanostructures directly on filter paper. The width of nanostructures is only a few nanometers and they contain high concentration of low-coordination atoms. Our approach involves the immersion and evaporation of Au precursor solution on the filter paper and its subsequent reduction. This approach generates filter paper-based gold substrates (FPGS) not only in a simple and straightforward fashion that can be executed in a matter of minutes but can also be easily scaled up for large-scale production. Owing to their surfactant-free nature, FPGS are well suited for the degradation of both cationic and anionic dyes by providing large unhindered surface for dye adsorption. The FPGS were able to completely degrade methyl orange (MO) and methylene blue (MB) dyes and also showed excellent reusability and stability

Design Simulation of Czerny&ndash;Turner Configuration-Based Raman Spectrometer Using Physical Optics Propagation Algorithm

We report the design simulation of the Raman spectrometer using Zemax optical system design software. The design is based on the Czerny&ndash;Turner configuration, which includes an optical system consisting of an entrance slit, two concave mirrors, reflecting type diffraction grating and an image detector. The system&rsquo;s modeling approach is suggested by introducing the corresponding relationship between detector pixels and wavelength, linear CCD receiving surface length and image surface dimension. The simulations were carried out using the POP (physical optics propagation) algorithm. Spot diagram, relative illumination, irradiance plot, modulation transfer function (MTF), geometric and encircled energy were simulated for designing the Raman spectrometer. The simulation results of the Raman spectrometer using a 527 nm wavelength laser as an excitation light source are presented. The present optical system was designed in sequential mode and a Raman spectrum was observed from 530 nm to 630 nm. The analysis shows that the system&rsquo;s image efficiency was quite good, predicting that it could build an efficient and cost-effective Raman spectrometer for optical diagnostics

Effects of Double Diffusion Convection on Third Grade Nanofluid through a Curved Compliant Peristaltic Channel

Nanofluids are potential heat transfer fluids with improved thermophysical properties and heat transfer performance. Double diffusion convection plays an important role in natural processes and technical applications. The effect of double convection by diffusion is not limited to oceanography, but is also evident in geology, astrophysics, and metallurgy. For such a vital role of such factors in applications, the authors have presented the analytical solutions of pumping flow of third-grade nanofluid and described the effects of double diffusion convection through a compliant curved channel. The model used for the third-grade nanofluid includes the presence of Brownian motion and thermophoresis. Additionally, thermal energy expressions suggest regular diffusion and cross-diffusion terms. The governing equations have been constructed for incompressible laminar flow of the non-Newtonian nanofluid along with the assumption of long wavelength. The obtained analytical expressions for velocity, temperature, and nanoparticle concentration have been sketched for various considerable parameters. The effects of regular buoyancy ratio, buoyancy parameter, modified Dufour parameter, and Dufour-solutal Lewis number have been analyzed along with wall properties and pumping characteristics. This study concludes that fluid becomes hotter with increase in regular buoyancy ratio and a modified Dufour parameter, but a decrease in temperature is observed for the buoyancy parameter. Moreover, the solutal concentration is behaving inversely against the Defour-Solutal Lewis number