The unprecedented global pandemic known as SARS-CoV-2 has exercised to its limits nearly all aspects of modern viral diagnostics. In doing so, it has illuminated both the advantages and limitations of current technologies. Tremendous effort has been put forth to expand our capacity to diagnose this deadly virus. In this work, we put forth key observations in the functionality of current methods for SARS-CoV-2 diagnostic testing. These methods include nucleic acid amplification-, CRISPR-, sequencing-, antigen-, and antibody-based detection methods. Additionally, we include analysis of equally critical aspects of COVID-19 diagnostics, including sample collection and preparation, testing models, and commercial response. We emphasize the integrated nature of assays, wherein issues in sample collection and preparation could impact the overall performance in a clinical setting.

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Nanosphere lithography (NSL) (also known as colloidal lithography) is a simple, bottom-up fabrication technique that enables pattern generation at the nanoscale via self-assembly of nanospheres on a substrate. [1] Compared to top-down nanoscale patterning techniques such as deep UV or electron-beam lithography, NSL has advantages of high throughput, low cost, and versatility. Specifically, lift-off patterning using NSL can be used to create patterns of metals, insulators, and organic semiconductors on a variety of substrate materials with sub-100 nm feature sizes. [2] A variety of nanoscale patterns have been demonstrated with NSL, including: triangles, rings, dots, rods, bimetallic "cup-like structures", and wires. [3,4] The success of NSL is due in large part to the ability to manufacture nanospheres with tight size tolerances (e.g., <5% size variation [2]), and the ability to form singleand multilayer nanosphere patterns on a wide variety of substrates using facile methods such as spin-coating, [2] solvent evaporation, [5] drop-casting, [6] dip coating, [7] and electrophoretic deposition, [8,9] to name a few. As a result, researchers have used NSL as a patterning approach for numerous applications including: surfaceenhanced Raman scattering, [10,11] lightemitting diode micro-lenses, [12] nanogap electrodes for single-molecule electronics, [13] semiconductor nanowires for photovoltaic cells, [14,15] and nanohole arrays for transparent conducting electrodes, [16-18] as examples. One of the main factors that limits current practical application of NSL is the ability to reproducibly pattern large areas of defect-free nanosphere monolayers or multi-layers. In a perfectly assembled monolayer NSL pattern, the nanospheres are arranged in hexagonal close-packed (HCP) formation. In practice, self-assembled monolayers are subject to crystalline defects, incomplete surface coverage, and multi-layer stacking that limit the useable surface area for NSL applications. [1] The origin of these defects depends on the self-assembly method, and may include grain boundary formation originating from "impurity atoms" (i.e., nanospheres that fall outside strict size and/or shape tolerances), [9] an imbalance between rates of capillary-induced self-assembly versus convective transport of nanospheres to the air-liquid contact line, [19,20] a hydrophilic substrate, [19] and/or post-growth crack formation during drying. [20,21] Although nanosphere monolayers can be formed using simple methods such as those listed previously, the resulting patterns-including defects and areas of continuous coverage-are highly sensitive to assembly parameters. For example, nanosphere spin-coating is sensitive to spin speeds, ramp rates, sphere concentration, solvent volatility, and substrate surface chemistry; [1,22] more generally, convective self-assembly mechanisms depend on wetting angles, temperature and relative

Nanosphere lithography employs single- or multilayer self-assembled nanospheres as a template for bottom-up nanoscale patterning. The ability to produce self-assembled nanospheres with minimal packing defects over large areas is critical to advancing applications of nanosphere lithography. Spin coating is a simple-to-execute, high-throughput method of nanosphere self-assembly. The wide range of possible process parameters for nanosphere spin coating, howeverand the sensitivity of nanosphere self-assembly to these parameterscan lead to highly variable outcomes in nanosphere configuration by this method. Finding the optimum process parameters for nanosphere spin coating remains challenging. This work adopts a design-of-experiments approach to investigate the effects of seven factorsnanosphere wt%, methanol/water ratio, solution volume, wetting time, spin time, maximum revolutions per minute, and ramp rateon two response variablespercentage hexagonal close packing and macroscale coverage of nanospheres. Single-response and multiple-response linear regression models identify main and two-way interaction effects of statistical significance to the outcomes of both response variables and enable prediction of optimized settings. The results indicate a tradeoff between the high ramp rates required for large macroscale coverage and the need to minimize high shear forces and evaporation rates to ensure that nanospheres properly self-assemble into hexagonally packed arrays.

We examined the effects of humidity on the metabolic rates and respiratory patterns of Gromphadorhina portentosa (Schaum) (Blattodea: Blaberidae) to determine whether insects transition from continuous, cyclical, and discontinuous (DGC) respiration in response to water conservation. Eight male G. portentosa were placed under five different humidity treatments (0, 23, 40, 60, 80% RH). Using flow through respirometry we: (i) determined the effect of humidity on metabolic rate; (ii) observed if changes in metabolic rate were correlated with changes in closed/flutter (CF) or the open (O) phase of DGC; and (iii) determined whether increased spiracular closure was correlated with an increase in water retention. Although G. portentosa had similar rates of CO2 release when placed under 0, 40, 60, and 80% RH, cockroaches placed at 23% RH had a significantly higher metabolic rate. There was no effect of humidity on the duration of the CF phase of the DGC. However, the O phase of DGC was significantly longer when G. portentosa was placed at humidity levels above 23% RH. Interestingly, we saw that the average rate of mass lost to the environment did not change when cockroaches were placed at humidity levels ranging from 0 to 80% RH. This suggests that modulation of the spiracles allows G. portentosa to regulate the amount of water lost to the environment.