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In this work, the chemical composition, chemical structures, and sugar release were evaluated for sweet sorghum bagasse (SSB) biomass in response to alkaline pretreatments and enzymatic hydrolysis. Five different ratios of 2 M sodium hydroxide (NaOH) and sodium carbonate (Na2CO3) solutions were used for biomass fractionation along with two heat treatment conditions, 85°C and 150°C for 1 h. Sugar yields from enzymatic hydrolysis were measured at different durations up to 72 h. SSB samples pretreated at high temperature using alkaline solutions containing equal amounts of Na2CO3 and NaOH favored retaining cellulose content (up to 90%) while effectively removing hemicellulose (65%) and lignin (92%). The high-temperature pretreatment conditions resulted in improved delignification, higher sugar concentrations, and sugar yields. Pretreatment solutions consisting of 50% or more NaOH produced higher glucose yields (85%–90%) and total sugar concentrations. Moreover, pretreatment solutions containing Na2CO3 improved the hydrolysis rates allowing SSB samples reach maximum yields faster than those without it, 48 versus 72 h. Results showed pretreatment methods combining NaOH and Na2CO3 were effective at promoting SSB biomass conversion, increasing sugar recovery after hydrolysis, and reducing the hydrolysis duration, all of which are desirable and cost beneficial.

Abstract As the SARS‐CoV‐2 virus spread throughout the world, millions of positive cases of COVID‐19 were registered and, even though there are millions of people already vaccinated against SARS‐CoV‐2, a large part of the global population remains vulnerable to contracting the virus. Massive nasopharyngeal sample collection in Puerto Rico at the beginning of the pandemic was limited by the scarcity of trained personnel and testing sites. To increase SARS‐CoV‐2 molecular testing availability, we evaluated the diagnostic accuracy of self‐collected nasal, saliva, and urine samples using the TaqPath reverse transcription polymerase chain reaction (RT‐PCR) COVID‐19 kit to detect SARS‐CoV‐2. We also created a colorimetric loop‐mediated isothermal amplification (LAMP) laboratory developed test (LDT) to detect SARS‐CoV‐2, as another strategy to increase the availability of molecular testing in community‐based laboratories. Automated RNA extraction was performed in the KingFisher Flex instrument, followed by PCR quantification of SARS‐CoV‐2 on the 7500 Fast Dx RT‐PCR using the TaqPath RT‐PCR COVID‐19 molecular test. Data was interpreted by the COVID‐19 Interpretive Software from Applied Biosystems and statistically analyzed with Cohen's kappa coefficient (k). Cohen's kappa coefficient (k) for paired nasal and saliva samples showed moderate agreement (0.52). Saliva samples exhibited a higher viral load. We also observed 90% concordance between LifeGene‐Biomarks' SARS‐CoV‐2 Rapid Colorimetric LAMP LDT and the TaqPath RT‐PCR COVID‐19 test. Our results suggest that self‐collected saliva is superior to nasal and urine samples for COVID‐19 testing. The results also suggest that the colorimetric LAMP LDT is a rapid alternative to RT‐PCR tests for the detection of SARS‐CoV‐2. This test can be easily implemented in clinics, hospitals, the workplace, and at home; optimizing the surveillance and collection process, which helps mitigate global public health and socioeconomic upheaval caused by airborne pandemics.

Abstract Introduction The severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) pandemic revealed a worldwide lack of effective molecular surveillance networks at local, state, and national levels, which are essential to identify, monitor, and limit viral community spread. SARS‐CoV‐2 variants of concern (VOCs) such as Alpha and Omicron, which show increased transmissibility and immune evasion, rapidly became dominant VOCs worldwide. Our objective was to develop an evidenced‐based genomic surveillance algorithm, combining reverse transcription polymerase chain reaction (RT‐PCR) and sequencing technologies to quickly identify highly contagious VOCs, before cases accumulate exponentially. Methods Deidentified data were obtained from 508,969 patients tested for coronavirus disease 2019 (COVID‐19) with the TaqPath COVID‐19 RT‐PCR Combo Kit (ThermoFisher) in four CLIA‐certified clinical laboratories in Puerto Rico (n = 86,639) and in three CLIA‐certified clinical laboratories in the United States (n = 422,330). Results TaqPath data revealed a frequency of S Gene Target Failure (SGTF) > 47% for the last week of March 2021 in both, Puerto Rico and US laboratories. The monthly frequency of SGTF in Puerto Rico steadily increased exponentially from 4% in November 2020 to 47% in March 2021. The weekly SGTF rate in US samples was high (>8%) from late December to early January and then also increased exponentially through April (48%). The exponential increase in SGFT prevalence in Puerto Rico was concurrent with a sharp increase in VOCs among all SARS‐CoV‐2 sequences from Puerto Rico uploaded to Global Influenza Surveillance and Response System (GISAID) (n = 461). Alpha variant frequency increased from

Abstract Carbonized lignin has been proposed as a sustainable and domestic source of activated, amorphous, graphitic, and nanostructured carbon for many industrial applications as the structure can be tuned through processing conditions. However, the inherent variability of lignin and its complex physicochemical structure resulting from feedstock and pulping selection make the Process‐Structure‐Property‐Performance (PSPP) relationships hard to define. In this work, radial distribution functions (RDFs) from synchrotron X‐ray and neutron scattering of lignin‐based carbon composites (LBCCs) are investigated using the Hierarchical Decomposition of the Radial Distribution Function (HDRDF) modelling method to characterize the local atomic environment and develop quantitative PSPP relationships. PSPP relationships for LBCCs defined by this work include crystallite size dependence on lignin feedstock as well as increasing crystalline volume fraction, nanoscale composite density, and crystallite size with increasing reduction temperature.

Renewable resources such as lignocellulosic biomass are effective at producing fermentable sugars during enzymatic hydrolysis when pretreated. Optimizing pretreatment methods for delignification while maintaining sustainability and low processing costs requires innovative strategies such as reusing greenhouse gas emissions for materials processing. Corn stover, an agricultural waste residue, was pretreated with 2.2 M Na2CO3 produced from CO2 captured via absorption in a 5 M NaOH solution. Composition analysis of the pretreated corn stover exhibited higher cellulose content (40.96%) and less lignin (16.50%) than the untreated biomass. Changes in the chemical structures are visible in the FTIR-ATR spectra, particularly in the cellulose and lignin-related absorption bands. The sugar release from hydrolysis was evaluated at different time intervals and by varying two enzyme ratios of CTec2-to-HTec2 (2:1 and 3:1). Enzymatic hydrolysis produced higher and more stable glucose yields for the pretreated biomass, surpassing 90% after 24 h using the 3:1 enzyme ratio. Sugar concentrations notably increased after pretreatment and even more when using the cellulase-rich enzyme solution. The maximum glucose, xylose, and arabinose recovered were 44, 19, and 2.3 g L−1. These results demonstrate the viability of capturing CO2 and converting it into an efficient Na2CO3 pretreatment for corn stover biomass. Additional processing optimizations depend on the combination of physicochemical parameters selected.

Renewable resources such as lignocellulosic biomass are effective at producing fermentable sugars during enzymatic hydrolysis when pretreated. Optimizing pretreatment methods for delignification while maintaining sustainability and low processing costs requires innovative strategies such as reusing greenhouse gas emissions for materials processing. Corn stover, an agricultural waste residue, was pretreated with 2.2 M N a 2 C O 3 produced from C O 2 captured via absorption in a 5 M NaOH solution. Composition analysis of the pretreated corn stover exhibited higher cellulose content (40.96%) and less lignin (16.50%) than the untreated biomass. Changes in the chemical structures are visible in the FTIR-ATR spectra, particularly in the cellulose and lignin-related absorption bands. The sugar release from hydrolysis was evaluated at different time intervals and by varying two enzyme ratios of CTec2-to-HTec2 (2:1 and 3:1). Enzymatic hydrolysis produced higher and more stable glucose yields for the pretreated biomass, surpassing 90% after 24 h using the 3:1 enzyme ratio. Sugar concentrations notably increased after pretreatment and even more when using the cellulase-rich enzyme solution. The maximum glucose, xylose, and arabinose recovered were 44, 19, and 2.3 g   L −1. These results demonstrate the viability of capturing C O 2 and converting it into an efficient N a 2 C O 3 pretreatment for corn stover biomass. Additional processing optimizations depend on the combination of physicochemical parameters selected. [ABSTRACT FROM AUTHOR]

Late-stage cancers lack effective treatment, underscoring the need for early diagnosis to improve prognosis and decrease mortality rates. Molecular markers, such as DNA methylation, offer promise in early cancer detection. The present study compared commercial kits for analyzing DNA from cervical liquid cytology samples in cancer screening. Rapid bisulfite conversion kits using silica spin-columns and magnetic beads were assessed against standard DNA extraction and bisulfite conversion methods for profiling DNA methylation using quantitative methylation-specific PCR. β-actin amplification indicated the suitability of small sample volumes for methylation studies using either the pellet or supernatant (cell-free DNA) parts. Comparison of Bisulfite Conversion Kit-Whole Cell (Abcam), Methylamp Bisulfite Modification (Epigentek), EpiTect Fast LyseAll Bisulfite Kit (Qiagen GmbH) and EZ DNA Methylation-Direct Kit (Zymo Research Corp.) showed no significant differences in β-actin cycle threshold values. EZ-96 DNA Methylation-Lightning MagPrep (Zymo Research Corp.), a hybrid kit in a 96-well plate format, exhibited swift turnaround time and similar amplification efficiency. Automation with magnetic bead kits increased throughput without compromising amplification efficiency in open PCR systems. Cost analysis favored direct kits over the gold standard manual protocol. This comparison aids in selecting cost-effective DNA methylation diagnostic tests. The present study confirmed comparable kit performance in methylation-based analysis, highlighting the adequacy of cytology samples and the potential of bodily fluids as alternatives for liquid biopsy. [ABSTRACT FROM AUTHOR]

Carbonized lignin has been proposed as a sustainable and domestic source of activated, amorphous, graphitic, and nanostructured carbon for many industrial applications as the structure can be tuned through processing conditions. However, the inherent variability of lignin and its complex physicochemical structure resulting from feedstock and pulping selection make the Process‐Structure‐Property‐Performance (PSPP) relationships hard to define. In this work, radial distribution functions (RDFs) from synchrotron X‐ray and neutron scattering of lignin‐based carbon composites (LBCCs) are investigated using the Hierarchical Decomposition of the Radial Distribution Function (HDRDF) modelling method to characterize the local atomic environment and develop quantitative PSPP relationships. PSPP relationships for LBCCs defined by this work include crystallite size dependence on lignin feedstock as well as increasing crystalline volume fraction, nanoscale composite density, and crystallite size with increasing reduction temperature. [ABSTRACT FROM AUTHOR]

Composite materials possessing both crystalline and amorphous domains, when subjected to X‐ray and neutron scattering, generate diffraction patterns that are often difficult to interpret. One approach is to perform atomistic simulations of a proposed structure, from which the analogous diffraction pattern can be obtained for validation. The structure can be iteratively refined until simulation and experiment agree. The practical drawback to this approach is the significant computational resources required for the simulations. In this work, an alternative approach based on a hierarchical decomposition of the radial distribution function is used to generate a physics‐based model allowing rapid interpretation of scattering data. In order to demonstrate the breadth of this approach, it is applied to a series of carbon composites. The model is compared with atomistic simulation results in order to demonstrate that the contributions of the crystalline and amorphous domains, as well as their interfaces, are correctly captured. Because the model is more efficient, additional structural refinement is performed to increase the agreement of the simulation result with the experimental data. The model achieves a reduction in computational effort of six orders of magnitude relative to simulation. The model can be generally extended to other composite materials. [ABSTRACT FROM AUTHOR]

Lignin, an abundant organic polymer and a byproduct of pulp and biofuel production, has potential applications owing to its high carbon content and aromatic structure. Processing-structure relationships are difficult to predict because of the heterogeneity of lignin. This work discusses the roles of unit operations in the carbonization process of softwood lignin, and their resulting impacts on the material structure and electrochemical properties in application as the anode in lithium-ion cells. The processing variables include the lignin source, temperature, and duration of thermal stabilization, pyrolysis, and reduction. Materials are characterized at the atomic and microscales. High-temperature carbonization, at 2000 °C, produces larger graphitic domains than at 1050 °C, but results in a reduced capacity. Coulombic efficiencies over 98 % are achieved for extended galvanostatic cycling. Consequently, a properly designed carbonization process for lignin is well suited for the generation of low-cost, high-efficiency electrodes. [ABSTRACT FROM AUTHOR]

Introduction: The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic revealed a worldwide lack of effective molecular surveillance networks at local, state, and national levels, which are essential to identify, monitor, and limit viral community spread. SARS-CoV-2 variants of concern (VOCs) such as Alpha and Omicron, which show increased transmissibility and immune evasion, rapidly became dominant VOCs worldwide. Our objective was to develop an evidenced-based genomic surveillance algorithm, combining reverse transcription polymerase chain reaction (RT-PCR) and sequencing technologies to quickly identify highly contagious VOCs, before cases accumulate exponentially., Methods: Deidentified data were obtained from 508,969 patients tested for coronavirus disease 2019 (COVID-19) with the TaqPath COVID-19 RT-PCR Combo Kit (ThermoFisher) in four CLIA-certified clinical laboratories in Puerto Rico (n = 86,639) and in three CLIA-certified clinical laboratories in the United States (n = 422,330)., Results: TaqPath data revealed a frequency of S Gene Target Failure (SGTF) > 47% for the last week of March 2021 in both, Puerto Rico and US laboratories. The monthly frequency of SGTF in Puerto Rico steadily increased exponentially from 4% in November 2020 to 47% in March 2021. The weekly SGTF rate in US samples was high (>8%) from late December to early January and then also increased exponentially through April (48%). The exponential increase in SGFT prevalence in Puerto Rico was concurrent with a sharp increase in VOCs among all SARS-CoV-2 sequences from Puerto Rico uploaded to Global Influenza Surveillance and Response System (GISAID) (n = 461). Alpha variant frequency increased from <1% in the last week of January 2021 to 51.5% of viral sequences from Puerto Rico collected in the last week of March 2021., Conclusions: According to the proposed evidence-based algorithm, approximately 50% of all SGTF patients should be managed with VOCs self-quarantine and contact tracing protocols, while WGS confirms their lineage in genomic surveillance laboratories. Our results suggest this workflow is useful for tracking VOCs with SGTF., (© 2022 The Authors. Immunity, Inflammation and Disease published by John Wiley & Sons Ltd.)