The Monoclonal Antibody Cocktail in SARS-CoV 2: A Bonanza for Patients With Chronic Lymphocytic Leukemia?

Monoclonal antibody cocktail is currently one of the most promising approaches being studied in the management of severe acute respiratory syndrome coronavirus 2 (SARS CoV-2). We present a case of an elderly patient with coronavirus disease (COVID-19) and Chronic lymphocytic leukaemia (CLL) who had recurrent episodes of desaturation and admission in intensive care unit (ICU) despite receiving the treatment for moderate to severe COVID-19. After careful selection, weighing the benefits and risks, the patient was started on the combination of the two monoclonal antibodies, casirivimab and imdevimab. The results suggest that this could be a game changer in COVID-19 with a focused approach of management of COVID-19 positive patients especially in the vulnerable population

Modeling and Source Apportionment of Primary and Secondary PM\u3csub\u3e2.5\u3c/sub\u3e in the Atmosphere

Source apportionment of PM2.5 is important to identify the source categories that are responsible for the concentrations observed at a particular receptor. Although receptor models have been used to do source apportionment, they do not fully take into account the chemical reactions (including photochemical reactions) involved in the formation of secondary fine particles. Secondary fine particles are formed from photochemical and other reactions involving precursor gases such as sulfur dioxide (SO2), oxides of nitrogen (NOx), ammonia (NH3) and volatile organic compounds (VOC). The purpose of this research work was to model primary and secondary PM2.5 concentrations in the state of Tennessee (TN) and to identify the major source categories contributing to ambient fine particles. On-road mobile and point source inventories for the state of TN were estimated and compiled by the research group at the University of Tennessee (UT). The national emissions inventory (NEI) for the year 1999 was used for the other states. The Models3/CMAQ modeling system was used for the photochemical/secondary particulate matter modeling. The modeling domain consisted of a nested 36-12-4 km domain. The 4 km domain covered the entire state of TN. The episode chosen for the modeling runs was August 29 to September 9, 1999. Different scenarios were run to quantify the contribution of the various source categories. The overall model performance was found to be satisfactory. On average, the coal-fired power plants formed the major source category accounting for about 29 to 39% of the 24-hr average total PM2.5 concentration. On-road mobile sources contributed around 17 to 24%, of which, about 60% was from fugitive dust on paved and unpaved roads. Non-road mobile sources contributed about 3 to 6%. Non-linearity issues were encountered and recommendations were made for further research. The results of this work will be helpful in addressing policy issues targeted at designing control strategies to meet the National Ambient Air Quality Standard (NAAQS) for PM2.5 in TN and the surrounding states

Optical refrigeration under laser and solar irradiation

The concept of optical refrigeration dates back to 1929, when Pringsheim recognized that thermal energy associated with the translational degrees of freedom of isolated atoms could be reduced by the process of anti-Stokes fluorescence. Optical refrigeration of a solid was first experimentally demonstrated in 1995 with the Ytterbium-doped fluorozirconate glass by Epstein and his team and since then this invigorating field has garnered much scientific interest for development of an all optical refrigerator. The present works discusses the recent candidate materials including crystals, semiconductors, and ionically doped glasses. Cooling processes and necessary conditions for cooling are outlined, and general thermodynamic limitations are discussed. 10% wt. Ytterbium doped Yttrium Lithium Fluoride (Yb+3:YLF) is chosen as the candidate active material. The Carnot efficiency for laser and sun-light as a pump source is evaluated using a narrow-band approximation outlined by Stephen and his team. A quantum-mechanical cooling model based on Epstein and his team, is developed. In the proposed system, the candidate material is placed on a magnetically suspended platform inside a vacuum chamber and illuminated with laser light with the appropriate wavelength in the near infrared region. The dynamics of important cooling parameters are simulated and studied. The cooling effects due to radiative relaxation compete with the heating effects due to parasitic absorption and non-radiative relaxation but net cooling is observed confirming validity of light source and material parameter selection. In addition to laser, the conventional source of pump radiation, sun-light as a pump input to the quantum-mechanical model is simulated and the effects on the cooling power and efficiency are studied. To enhance the energy efficiency of the system, fluorescence recovery schemes using photovoltaics are built and studied. Suggestions for experimental realization are given. The developed model can be base for designing a practical optical refrigeration system for laser and sun-light based optical sources. Electrical Engineering | Sustainable Energy Technolog

An evaluation of mass absorption cross-section for optical carbon analysis on Teflon filter media

<p>Black carbon (BC) or elemental carbon (EC) is a by-product of incomplete fuel combustion, and contributes adversely to human health, visibility, and climate impacts. Previous studies have examined nondestructive techniques for particle light attenuation measurements on Teflon® filters to estimate BC. The incorporation of an inline Magee Scientific OT21 transmissometer into the MTL AH-225 robotic weighing system provides the opportunity to perform optical transmission measurements on Teflon filters at the same time as the gravimetric mass measurement. In this study, we characterize the performance of the inline OT21, and apply it to determine the mass absorption cross-section (MAC) of PM_2.5 BC across the United States. We analyzed 5393 archived Teflon® filters from the Chemical Speciation Network (CSN) collected during 2010–2011 and determined MAC by comparing light attenuation on Teflon® filters to corresponding thermal EC on quartz-fiber filters. Results demonstrated the importance of the initial transmission (<i>I₀</i>) value used in light attenuation calculations. While light transmission varied greatly within filter lots, the average <i>I₀</i> of filter blanks during the sampling period provided an estimate for archived filters. For newly collected samples, it is recommended that filter-specific <i>I₀</i> measurements be made (i.e., same filter before sample collection). The estimated MAC ranged from 6.9 to 9.4 m²/g and varied by region and season across the United States, indicating that using a default value may lead to under- or overestimated BC concentrations. An analysis of the chemical composition of these samples indicated good correlation with EC for samples with higher EC content as a fraction of total PM_2.5 mass, while the presence of light-scattering species such as crustal elements impacted the correlation affecting the MAC estimate. Overall, the method is demonstrated to be a quick, cost-effective approach to estimate BC from archived and newly sampled Teflon® filters by combining both gravimetric and BC measurements.</p> <p><i>Implications</i>: Robotic optical analysis is a valid, cost-effective means to obtain a vast amount of BC data from archived and current routine filters. A tailored mass absorption cross-section by region and season is necessary for a more representative estimate of BC. Initial light transmission measurements play an important role due to the variability in blank filter transmission. Combining gravimetric mass and BC analysis on a single Teflon® filter reduces costs for monitoring agencies and maximizes data collection.</p

Comparison of Continuous and Filter-Based Carbon Measurements at the Fresno Supersite

Results from six continuous and semicontinuous black carbon (BC) and elemental carbon (EC) measurement methods are compared for ambient samples collected from December 2003 through November 2004 at the Fresno Supersite in California. Instruments included a multi-angle absorption photometer (MAAP; wavelength 670 nm); a dual-wavelength (wavelengths 370 and 880 nm) aethalometer; seven-color (wavelengths 370, 470, 520, 590, 660, 880, and 950 nm) aethalometers; the Sunset Laboratory carbon aerosol analysis field instrument; a photoacoustic light absorption analyzer (wavelength 1047 nm); and the R&P 5400 ambient carbon particulate monitor. All of these acquired BC or EC measurements over periods of 1 min to 1 hr. Twenty-fourhour integrated filter samples were also acquired and analyzed by the Interagency Monitoring of Protected Visual Environments (IMPROVE) thermal/optical reflectance carbon analysis protocol. Site-specific mass absorption efficiencies estimated by comparing light absorption with IMPROVE EC concentrations were 5.5m2/g for the MAAP, 10 m2/g for the aethalometer at a wavelength of 880 nm, and 2.3 m2/g for the photoacoustic analyzer; these differed from the default efficiencies of 6.5, 16.6, and 5m2/g, respectively. Scaling absorption by inverse wavelength did not provide equivalent light absorption coefficients among the instruments for the Fresno aerosol measurements. Ratios of light absorption at 370 nm to those at 880 nm from the aethalometer were nearly twice as high in winter as in summer. This is consistent with wintertime contributions from vehicle exhaust and from residential wood combustion, which is believed to absorb more shorter-wavelength light. To reconcile BC and EC measurements obtained by different methods, a better understanding is needed of the wavelength dependence of light-absorption and mass-absorption efficiencies and how they vary with different aerosol composition

Omalizumab rescue therapy in refractory status asthmaticus

Introduction: Refractory status asthmaticus (RSA) is a severe, life-threatening form of asthma exacerbation that persists despite aggressive treatment with systemic corticosteroids, bronchodilators, and other supportive measures. Omalizumab, a monoclonal antibody that targets IgE, has been approved for treating severe allergic asthma and is effective in reducing the frequency of exacerbations and improving asthma control. Limited evidence exists regarding the use of Omalizumab in RSA, but some studies have suggested that it may have a role in its management. Case: A 39-year-old male with a decade-long history of asthma presented to the emergency department intubated and unresponsive to pharmacological therapy. The patient\u27s IgE levels were elevated, and Omalizumab was administered after a comprehensive evaluation. The patient made a dramatic recovery and was successfully weaned off the ventilator within 24 h of receiving Omalizumab. He made an uneventful recovery and was discharged home on Omalizumab once every two weeks with regular follow-ups. Discussion and conclusion: Per our literature search, only 3 cases have been reported where Omalizumab was administered to patients with RSA to wean them off ventilatory support successfully. This case study adds to the existing data on the potential benefits of Omalizumab in managing RSA. It suggests it may be a valuable treatment option for patients who do not respond to standard therapy. However, further research is needed to determine the efficacy and safety of Omalizumab in this population