Slope Of Unity Research Articles

Deriving the linear dynamic range of next-generation thin-film photodiodes: Pitfalls and guidelines

With the use of next-generation semiconductors, notably organic and perovskite materials with remarkable optoelectronic and mechanical properties, thin-film photodiodes are progressing rapidly to rival their inorganic counterparts. However, to ensure a trustworthy comparison among the reported works, it is imperative that the measurement techniques for the figure of merits be unified and standardized. In this Letter, the possible causes of misrepresentation in the linear dynamic range (LDR) values are thoroughly discussed. The role of unity slope in defining the deviation point is examined, and the chances of misinterpretation when adopting different definitions are explained using a representative organic photodiode system. Furthermore, certain criteria are put out to standardize the LDR representation, which could be a crucial step toward facilitating the progress in this promising field via a more rational comparison of literature reports.

Modeling the Partitioning of Anionic Carboxylic and Perfluoroalkyl Carboxylic and Sulfonic Acids to Octanol and Membrane Lipid.

Perfluoroalkyl carboxylic and sulfonic acids (PFCAs and PFSAs, respectively) have low acid dissociation constant values and are, therefore, deprotonated under most experimental and environmental conditions. Hence, the anionic species dominate their partitioning between water and organic phases, including octanol and phospholipid bilayers which are often used as model systems for environmental and biological matrices. However, data for solvent-water (SW) and membrane-water partition coefficients of the anion species are only available for a few per- and polyfluoroalkyl substances (PFAS). In the present study, an equation is derived using a Born-Haber cycle that relates the partition coefficients of the anions to those of the corresponding neutral species. It is shown via a thermodynamic analysis that for carboxylic acids (CAs), PFCAs, and PFSAs, the log of the solvent-water partition coefficient of the anion, log KSW (A- ), is linearly related to the log of the solvent-water partition coefficient of the neutral acid, log KSW (HA), with a unity slope and a solvent-dependent but solute-independent intercept within a PFAS (or CA) family. This finding provides a method for estimating the partition coefficients of PFCAs and PFSAs anions using the partition coefficients of the neutral species, which can be reliably predicted using quantum chemical methods. In addition, we have found that the neutral octanol-water partition coefficient, log KOW , is linearly correlated to the neutral membrane-water partition coefficient, log KMW ; therefore, log KOW , being a much easier property to estimate and/or measure, can be used to predict the neutral log KMW . Application of this approach to KOW and KMW for PFCAs and PFSAs demonstrates the utility of this methodology for evaluating reported experimental data and extending anion property data for chain lengths that are unavailable. Environ Toxicol Chem 2023;00:1-12. © 2023 SETAC.

58 Evaluation of indigestible neutral detergent fiber methodology and its use as a marker to estimate hay digestibility in horses

Indigestible neutral detergent fiber (iNDF) is routinely used as an internal marker to estimate dry matter digestibility (DMD) of feeds in ruminants but has been applied less frequently to horses. Measurement of iNDF requires prolonged incubation of samples in microbial inoculum. Despite inherent differences in microbial fiber degradation between species, we hypothesized that bovine and equine sources of inoculum would produce similar measures of iNDF and both would yield accurate estimates of DMD in horses. The aim of this study was to directly measure fecal output and DMD in horses using total fecal collection and compare it to estimates derived from iNDF that had been quantified by different methods. Five mature Quarter Horse geldings (552 ± 14 kg) were fed 5 hays differing in fiber composition in a 5 × 5 Latin square design experiment. Hays offered at 1.6% BW included: alfalfa (Medicago sativa, ALFA), orchardgrass (Dactylis glomerata, ORCH), and bermudagrass (Cynodon dactylon) harvested at 4 (BG-4), 6 (BG-6), and 8 wk of regrowth (BG-8). Each period consisted of an 8-d diet adaptation followed by a 3-d total fecal collection (TC). Hay and fecal samples were dried and ground, placed in 25-μm filter bags, and incubated for 288 h in 4 different inocula to determine iNDF: in situ in rumen-cannulated cows, in vitro in rumen fluid (RF), in vitro in cecal fluid (CF), and in vitro in equine fecal inoculum (EF). Following incubation samples were analyzed for residual neutraldetergent fiber (ie, iNDF). Data were compared using a split plot within a Latin square whole plot design using mixed model ANOVA and linear regression. Mean iNDF recovery for in situ and EF (95%, 91%) was greater (P < 0.05) than CF and RF (88%, 85%; SEM 1.6%). Fecal output estimated by in situ and EF did not differ from that measured by TC but was overestimated by RF and CF methods (P < 0.05). An interaction of hay*method was observed for DMD (P = 0.01). For ALFA and BG-6, DMD determined by all iNDF methods aligned with DMD measured by TC. For ORCH and BG-4, only DMD estimates from in situ and EF were similar to TC. All iNDF methods underestimated DMD for BG-8. Linear regression of DMD for all hays measured by TC showed a stronger relationship with in situ and EF iNDF methods (R2 = 0.65, 0.64; RMSE 7.4, 7.2) than RF and CF iNDF methods (R2 = 0.56, 0.61; RMSE 8.6, 7.7), though all were significant (P < 0.01) and all equations approached unity (slope 1.0, intercept 0). Results show iNDF can be used in horses to estimate DMD across a variety of hays and may align better with TC when rumen in situ and EF methods are used to determine iNDF.

89 Performance of iADF as an internal marker for evaluating forage digestibility in horses

Total fecal collection (TFC) is considered the gold standard for evaluating diet digestibility; however, this method is time consuming, labor-intensive, and requires horses to wear collection harnesses and/or be confined to stalls for prolonged periods. Less frequent sampling of feces can be more practical and less disruptive to the management and routines of certain types of horses (e.g., horses in training, lactating mares, growing horses) but requires the use of a marker to estimate daily fecal output. Indigestible acid detergent fiber (iADF) is routinely used to determine dry matter digestibility (DMD) in cattle but evidence of its effectiveness as an internal marker in horses is limited. This study used 5 mature Quarter Horse geldings to compare fecal output and DMD determined with TFC to that estimated using iADF. Horses were fed alfalfa (Medicago sativa, ALF) or bermudagrass (Cynodon dactylon ‘Coastal’, CBG) hays at 1.6% BW/d in a crossover design. Hays were chosen to represent a large span in fiber concentration (ALF: 38% NDF, 30% ADF; CBG: 70% NDF, 35% ADF). Each period consisted of an 8-d diet adaptation followed by a 3-d TFC. Hays and daily composited fecal samples were analyzed for iADF using 2 methods: in situ incubation in a rumen-cannulated cow and in vitro incubation using equine fecal inoculum from a non-study donor. Samples were incubated for 288 h and sequentially analyzed to determineresidual neutral and acid detergent fibers, with the latter representing iADF. Data were compared using mixed model ANOVA and linear regression. Marker recovery of iADF averaged 98% (SEM 4%) and was similar between iADF methods and hays. Use of fecal inoculum yielded higher estimates of iADF intake (P < 0.01) and iADF excretion in feces (P < 0.01) than the rumen in situ iADF method. Daily fecal output and DMD estimated by rumen in situ iADF (P = 0.27, P = 0.29) and fecal inoculum iADF (P = 0.71, P = 0.79) both agreed with direct determination by TFC. Linear regression of DMD showed a strong relationship between TFC and both iADF methods (P < 0.001), with slightly better prediction when iADF was determined by rumen in situ (y = 0.81x + 7.1; R2 0.85; RMSE 4.8) than equine fecal inoculum (y = 0.79x + 10.0; R2 0.71; RMSE 7.0). Both equations approached a slope of unity and an intercept not different from zero (P > 0.10). Across all methods, DMD of ALF was higher (P < 0.01) than CBG. Findings support use of iADF as a marker to predict DMD of hays in horses. This study measured iADF in samples representing all feces excreted; thus, future work should verify the suitability of iADF as a marker when applied to fecal spot sampling.

Large-scale density and velocity field reconstructions with neural networks

ABSTRACT We assess a neural network (NN) method for reconstructing 3D cosmological density and velocity fields (target) from discrete and incomplete galaxy distributions (input). We employ second-order Lagrangian Perturbation Theory to generate a large ensemble of mock data to train an auto-encoder (AE) architecture with a Mean Squared Error (MSE) loss function. The AE successfully captures non-linear features arising from gravitational dynamics and the discreteness of the galaxy distribution. It preserves the positivity of the reconstructed density field and exhibits a weaker suppression of the power on small scales than the traditional linear Wiener filter (WF), which we use as a benchmark. In the density reconstruction, the reduction of the AE MSE relative to the WF is $\sim 15~{{\ \rm per\ cent}}$ , whereas for the velocity reconstruction a relative reduction of up to a factor of two can be achieved. The AE is advantageous to the WF at recovering the distribution of the target fields, especially at the tails. In fact, trained with an MSE loss, any NN estimate approaches the unbiased mean of the underlying target given the input. This implies a slope of unity in the linear regression of the true on the NN-reconstructed field. Only for the special case of Gaussian fields, the NN and WF estimates are equivalent. Nonetheless, we also recover a linear regression slope of unity for the WF with non-Gaussian fields.

ThePlanckclusters in the LOFAR sky

Context.The footprint of the recent second data release of the LOFAR Two-metre Sky Survey (LoTSS-DR2) covers 309PlanckSunyaev-Zeldovich (SZ) selected galaxy clusters, 83 of which host a radio halo and 26 host a radio relic(s). It provides an excellent opportunity to statistically study the properties of extended cluster radio sources, especially their connection with merging activities.Aims.We quantify cluster dynamic states to investigate their relation with the occurrence of extended radio sources. We also search for connections between intracluster medium (ICM) turbulence and nonthermal characteristics of radio halos in the LoTSS-DR2.Methods.We analyzedXMM-NewtonandChandraarchival X-ray data of allPlanckSZ clusters in the footprint of LoTSS-DR2. We computed concentration parameters and centroid shifts that indicate the dynamic states of the clusters. We also performed a power spectral analysis of the X-ray surface brightness fluctuations to investigate large-scale density perturbations and estimate the turbulent velocity dispersion. Furthermore, we searched for the relation between radio halo power and the turbulent dissipation flux channeled to particle acceleration.Results.The concentration parameters measured by the two telescopes agree well, but the centroid shift has a larger scatter. The surface brightness power spectral analysis results in a large scatter of the surface brightness and density fluctuation amplitudes. We therefore only found a marginal anticorrelation between density fluctuations and cluster relaxation state, and we did not find a correlation between density fluctuations and radio halo power. Nevertheless, the injected power for particle acceleration calculated from turbulent dissipation is correlated with the radio halo power, where the best-fit unity slope supports the turbulent (re)acceleration scenario. Two different acceleration models, transit-time damping and adiabatic stochastic acceleration, cannot be distinguished due to the large scatter of the estimated turbulent Mach number. We introduced a new quantity [kBT ⋅ YX]rRH, which is proportional to the turbulent acceleration power assuming a constant Mach number. This quantity is strongly correlated with radio halo power, where the slope is also unity.

Probing the inner local density of complex macromolecules by pyrene excimer formation.

The direct relationship existing between the average rate constant 〈k〉 for pyrene excimer formation and the local concentration [Py]loc of ground-state pyrenyl labels covalently attached to a macromolecule was established for 55 pyrene-labeled macromolecules (PyLM). These PyLM belonged to three different families of macromolecules with the first representing short monodisperse linear chains end-labeled with pyrene (polystyrene, poly(ethylene oxide), and poly(N-isopropyl acrylamide)), the second representing long polydisperse linear chains randomly labeled with pyrene (poly(methyl acrylate), poly(methyl methacrylate), polystyrene, poly(butyl methacrylate), poly(methoxyethyl methacrylate), and poly(N-isopropyl acrylamide)), and the third being comprised of two series of pyrene end-labeled low generation dendrimers with a bis(hydroxymethyl)propionic acid or a polyamidoamine backbone. The assumption, that the polymeric segments probed by an excited pyrenyl label covalently attached to one of these macromolecules obeyed Gaussian statistics, enabled the calculation of their square root average squared end-to-end distance (LPy), which was applied to calculate [Py]loc. The log-log plots of 〈k〉 as a function of [Py]loc yielded straight lines with a slope of unity for all families of macromolecules studied in four different organic solvents demonstrating the validity and generality of the 〈k〉-vs.-[Py]loc relationship. Since an experimentalist knows how the the pyrenyl labels are covalently attached onto a macromolecule, [Py]loc offers a means to probe the local density of a macromolecule, which can be employed to characterize its conformation in solution. Consequently, the 〈k〉-vs.-[Py]loc relationship provides a novel experimental means to probe the conformation of macromolecules which should establish pyrene excimer formation as an appealing method for conformational studies of macromolecules in solution, which should nicely complement scattering techniques.

The volumetric extended-Schmidt law: a unity slope

ABSTRACT We investigate the extended-Schmidt (ES) law in volume densities (ρSFR ∝ $(\rho _{\rm gas}\rho _{\rm star}^{0.5})^{\alpha ^{\rm VES}}$) for spatially resolved regions in spiral, dwarf, and ultra-diffuse galaxies (UDGs), and compare to the volumetric Kennicutt–Schmidt (KS) law (ρSFR ∝ $\rho _{\rm gas}^{\alpha ^{\rm VKS}}$). We first characterize these star formation laws in individual galaxies using a sample of 11 spirals, finding median slopes αVES = 0.98 and αVKS = 1.42, with a galaxy-to-galaxy rms fluctuation that is substantially smaller for the volumetric ES law (0.18 versus 0.41). By combining all regions in spirals with those in additional 13 dwarfs and one UDG into one single data set, it is found that the rms scatter of the volumetric ES law at given x-axis is 0.25 dex, which is also smaller than that of the volumetric KS law (0.34 dex). At the extremely low gas density regime as offered by the UDG, the volumetric KS law breaks down but the volumetric ES law still holds. On the other hand, as compared to the surface density ES law, the volumetric ES law instead has a slightly larger rms scatter, consistent with the scenario that the ES law has an intrinsic slope of αVES ≡1 but the additional observational error of the scale height increases the uncertainty of the volume density. The unity slope of the ES law implies that the star formation efficiency (= ρSFR/ρgas) is regulated by the quantity that is related to the $\rho _{\rm star}^{0.5}$.

Low-Reynolds-number oscillating boundary layers on adiabatic slopes

We investigate the instabilities and transition mechanisms of Boussinesq stratified boundary layers on sloping boundaries when subjected to oscillatory body forcing parallel to the slope. We examine idealized forms of boundary layers on hydraulically smooth abyssal slopes in tranquil mid- to low-latitude regions, where low-wavenumber internal tides gently heave isopycnals up and down adiabatic slopes in the absence of mean flows, high-wavenumber internal tides, shelf breaks, resonant tide–bathymetry interactions (critical slopes) and other phenomena associated with turbulence ‘hot spots’. In non-rotating low-Reynolds-number flow, increased stratification on the downslope phase has a relaminarizing effect, while on the upslope phase we find transition-to-turbulence pathways arise from shear production triggered by gravitational instabilities. When rotation is significant (low slope Burger numbers) we find that boundary layer turbulence is sustained throughout the oscillation period, resembling stratified Stokes–Ekman layer turbulence. Simulation results suggest that oscillating boundary layers on smooth slopes at low Reynolds number ($\textit {Re}\leqslant 840$), unity Prandtl number and slope Burger numbers greater than unity do not cause significant irreversible turbulent buoyancy flux (mixing), and that flat-bottom dissipation rate models derived from the tide amplitude are accurate within an order of magnitude.

Pharmacological characterization of the α2A-adrenergic receptor inhibiting rat hippocampal CA3 epileptiform activity: comparison of ligand efficacy and potency

The mechanism underlying the antiepileptic actions of norepinephrine (NE) is unclear with conflicting results. Our objectives are to conclusively delineate the specific adrenergic receptor (AR) involved in attenuating hippocampal CA3 epileptiform activity and assess compounds for lead drug development. We utilized the picrotoxin model of seizure generation in rat brain slices using electrophysiological recordings. Epinephrine (EPI) reduced epileptiform burst frequency in a concentration-dependent manner. To identify the specific receptor involved in this response, the equilibrium dissociation constants were determined for a panel of ligands and compared with established binding values for α1, α2, and other receptor subtypes. Correlation and slope of unity were found for the α2A-AR, but not other receptors. Effects of different chemical classes of α-AR agonists at inhibiting epileptiform activity by potency (pEC50) and relative efficacy (RE) were determined. Compared with NE (pEC50, 6.20; RE, 100%), dexmedetomidine, an imidazoline (pEC50, 8.59; RE, 67.1%), and guanabenz, a guanidine (pEC50, 7.94; RE, 37.9%), exhibited the highest potency (pEC50). In contrast, the catecholamines, EPI (pEC50, 6.95; RE, 120%) and α-methyl-NE (pEC50, 6.38; RE, 116%) were the most efficacious. These findings confirm that CA3 epileptiform activity is mediated solely by α2A-ARs without activation of other receptor systems. These findings suggest a pharmacotherapeutic target for treating epilepsy and highlight the need for selective and efficacious α2A-AR agonists that can cross the blood–brain barrier.

Development of an Environment and Climate Data Acquisition System (EC-DAQS) for Radio Propagation Studies

Most weather monitoring systems used for measuring meteorological parameters are imported. For many developing countries like Nigeria, importing measuring instruments is practically bedeviled with problems due to erratic exchange rates. This has hampered weather-related research especially in radio propagation studies where finite weather data are required. In the quest to develop a home-grown monitoring system, this paper presents an Environment and Climate data acquisition system (EC-DAQS). In the EC-DAQS, an Arduino Mega2560 microcontroller along with six environment and weather sensors were coded to measure, record and display atmospheric parameters. For digital signal processing and data logging, the sensors were interconnected to the microcontroller through an analogue-to-digital-converter (ADC). The measured data were displayed on a liquid crystal display (LCD) screen remotely connected to the controller. Temperature, Ultraviolet Violet (UV) rays, humidity and sound level were tested and calibrated with “off-the shelf” instruments. The mean bias error (MBE) and the root mean square error (RMSE) were used to validate the temperature readings from the EC-DAQS with readings from a standard infra-red thermometer. The low results of the MBE (0.16°C) and RMSE (0.51°C) – showed close proximity between the EC-DAQS and the standard infra-red digital thermometer measurements. Also, the equation obtained from modelling is a straight line of near unity slope (0.994) and a correlation of 99.98%. The EC-DAQS developed will be a useful meteorological instrument, and a suitable replacement for imported weather stations in terms of performance, cost and maintenance. It will also provide some invaluable data needed for radio-propagation research and applications.

Cucurbiturils mimicked by low polarizability solvents with pre-formed cavities: an empirical model to predict hydrocarbon selectivity.

Relative binding affinities of a series of nine rigid hydrocarbons towards the cavity formed by a portion of the inner wall of cucurbit[8]uril (CB[8]) and a positive auxiliary guest were determined by competitive 19F NMR titrations in deuterium oxide. The corresponding free binding energies were corrected by the hydrocarbon computed solvation energies to obtain their free energies of transfer from the gas phase to the CB[8]/auxiliary guest cavity. These energies correlate linearly with the hydrocarbon static polarizabilities, thereby suggesting that the selectivity is driven, perhaps exclusively, by dispersive interactions between the hydrocarbons and the tailor-made cavity, regardless of the degree of unsaturation of the guests. The free energies of transfer also correlate linearly with the energy released upon introduction of the hydrocarbon into a pre-formed cavity extruded from a solvent (benzene) selected to mimic the polarity and polarizability of the CB[8]/auxiliary probe cavity – and this, with a unity slope. Among other features, this empirical model also accurately predicts the relative binding affinities of various rigid hydrocarbons to CB[6] and CB[7], as well as noble gases to CB[5], when the macrocycles are mimicked with pre-formed cavities in perfluorohexane or perfluorohexane/benzene mixtures, both being notoriously non-polar and non-polarizable environments.

Mercury isotopic compositions in fine particles and offshore surface seawater in a coastal area of East China: implications for Hg sources and atmospheric transformations

Abstract. Isotopic compositions of Mercury (Hg) in atmospheric particles (HgPM) are probably the mixed results of emission sources and atmospheric processes. Here, we present Hg isotopic compositions in daily fine particles (PM2.5) collected from an industrial site (Chunxiao – CX) and a nearby mountain site (Daimeishan – DMS) in a coastal area of East China, and in surface seawater close to the industrial area, to reveal the influence of anthropogenic emission sources and atmospheric transformations on Hg isotopes. The PM2.5 samples displayed a significant spatial difference in δ202Hg. For the CX site, the negative δ202Hg values are similar to those of source materials, and the HgPM contents were well correlated with chemical tracers, indicating the dominant contributions of local industrial activities to HgPM2.5, whereas the observed positive δ202Hg at the DMS site was likely associated with regional emissions and extended atmospheric processes during transport. The Δ199Hg values in PM2.5 from the CX and DMS sites were comparably positive. The unity slope of Δ199Hg versus Δ201Hg over all data suggests that the odd mass independent fractionation (MIF) of HgPM2.5 was primarily induced by the photoreduction of Hg2+ in aerosols. The positive Δ200Hg values with a minor spatial difference were probably associated with the photooxidation of Hg0, which is generally enhanced in the coastal environment. Total Hg in offshore surface seawater was characterized by negative δ202Hg and near-zero Δ199Hg and Δ200Hg values, which are indistinguishable from Hg isotopes of source materials. Overall, the PM2.5 collected from industrial areas had comparable δ202Hg values but more positive Δ199Hg and Δ200Hg as compared to surface seawater. The results indicate that atmospheric transformations would induce the significant fractionation of Hg isotopes and obscure the Hg isotopic signatures of anthropogenic emissions.

Validation of a new cavity ring-down spectrometer for measuring tropospheric gaseous hydrogen chloride

Abstract. Reliable, sensitive, and widely available hydrogen chloride (HCl) measurements are important for understanding oxidation in many regions of the troposphere. We configured a commercial HCl cavity ring-down spectrometer (CRDS) for sampling HCl in the ambient atmosphere and developed validation techniques to characterize the measurement uncertainties. The CRDS makes fast, sensitive, and robust measurements of HCl in a high-finesse optical cavity coupled to a laser centred at 5739 cm−1. The accuracy was determined to reside between 5 %–10 %, calculated from laboratory and ambient air intercomparisons with annular denuders. The precision and limit of detection (3σ) in the 0.5 Hz measurement were below 6 and 18 pptv, respectively, for a 30 s integration interval in zero air. The response time of this method is primarily characterized by fitting decay curves to a double exponential equation and is impacted by inlet adsorption/desorption, with these surface effects increasing with relative humidity and decreasing with decreasing HCl mixing ratios. The minimum 90 % response time was 10 s and the equilibrated response time for the tested inlet was 2–6 min under the most and least optimal conditions, respectively. An intercomparison with the EPA compendium method for quantification of acidic atmospheric gases showed good agreement, yielding a linear relationship statistically equivalent to unity (slope of 0.97 ± 0.15). The CRDS from this study can detect HCl at atmospherically relevant mixing ratios, often performing comparably or better in sensitivity, selectivity, and response time than previously reported HCl detection methods.

A Question-Based Method to Calculate the Human Appropriation of Land for Food (HALF) Index

Global dietary consumption strongly determines agricultural land requirements. Yet, it is currently difficult for individual consumers to quantify the environmental impact of their individual diet. One relatively easy to understand metric is the Human Appropriation of Land for Food (HALF) index. The HALF index expresses the global land area percentage required for food production were the global population to consume one specific diet. Calculation of the HALF index is not trivial, making the index not suitable for individual consumers to assess their personal diet. The aim of this research is to develop and test a new method to calculate a personalized HALF index based on a limited set of multiple-choice questions that can be answered by a typical consumer. Considering the sensitivity of the original HALF index, we developed a set of ten multiple-choice questions that focus on the type and quantity of consumed animal products in addition to staple foods and overall consumption quantity. To illustrate a potential implementation, we present our question-based HALF index calculator in the form of an online graphical user interface. Across a sample of 23 country-specific diets, the question-based HALF index closely matches the original HALF index with a regression slope of near unity (r2 = 0.94, p &lt; 0.001). Our results indicate that the question-based HALF index can be used by individual consumers to quantify the consequences of their dietary choices on land use for agriculture.

Error-Aware Design Procedure to Implement Hardware-Efficient Logarithmic Circuits

State-of-the-art accurate logarithmic circuits involve shift-and-add operations which demand a high area cost. In this brief, a design procedure to implement a hardware-efficient logarithmic circuit is proposed which eliminate the use of shift operations. Logarithmic function curve is approximated using multiple regions of unity slope straight lines by adjusting the intercepts. The proposed procedure determines the number of regions and the corresponding intercepts to implement logarithmic circuit for a desired error constraint. Six logarithmic circuits were realized using the design procedure which exhibited maximum absolute error of 0.029, 0.0175, 0.0083, 0.0026, 0.0021 and 0.00179. The designs were synthesized using 65nm CMOS technology. The proposed designs showed up to 83.60%, 91.76% and 94.56% reduction in energy, energy-delay product and area-delay-power product when compared with those of state-of-the-art logarithmic circuits of comparable error.

Workspace analysis and trajectory tracking of a planar hybrid manipulator with ball screw feed drive

The hybrid manipulators have benefits of both serial as well as parallel manipulators. In this paper, a planar hybrid manipulator with six degrees-of-freedom is proposed; it consists of two parallel manipulators each having three degrees-of-freedom. The models for forward and inverse dynamic analysis of this manipulator are presented with bond graph approach. The actuators of the manipulator have ball screw feed drive mechanism to convert rotary motion into linear motion. There are basically three problems addressed in the paper. First, the models are simulated for trajectory tracking of a semi-circular path traced by the lower manipulator initially and then tracking of another semi circular path by upper manipulators. The second problem addressed is to develop the bond graph model of the hybrid manipulator with proportional control to reach a desired position from an initial position with an unity slope after few seconds. Finally, workspace analysis for given semi-circular trajectory is done with calculation of area of the workspace of lower, upper and hybrid manipulators. It is observed from the simulation that the response follows the desired trajectory within the permissible limit. The result indicates that manipulator follows nearly tangential path. It is seen from the result that the desired trajectory lies within the workspace boundary.

The Effect of Phosphodiesterase 4 Inhibition on Gene Expression Changes Produced by Long Acting β2‐adrenoceptor Agonists in BEAS‐2B Airway Epithelial Cells

Phosphodiesterase 4 (PDE4) inhibitors are prescribed as add‐on therapy to a subset of COPD patients that suffer from exacerbations despite treatment with a combination of long‐acting β2‐adrenoceptor agonists (LABA), long‐acting muscarinic receptor antagonist and inhaled corticosteroids. The molecular mechanisms of their beneficial effects in COPD are ill‐defined. We have previously shown that LABAs, through their effect on the canonical Gs‐cAMP pathway, promote genomic effects in airway epithelial cells. Herein, we hypothesized that PDE4 inhibitors, by inhibiting cAMP degradation, promote similar genomic effects, and further potentiate the effects of LABAs in a human bronchial epithelial cell line. Additionally, we investigated whether this interaction between PDE4 inhibitors and LABAs occurred in an additive or a synergistic manner.Gene expression changes were determined by population‐based RNA‐sequencing in BEAS‐2B cells treated with the PDE4 inhibitor, roflumilast N‐oxide (RNO), alone and in combination with LABA, salmeterol. RNO showed a weak stimulation of gene expression by itself but showed a strong rank‐order correlation with salmeterol‐induced gene expression changes, suggesting a common mechanism of action. RNO augmented the expression of all salmeterol‐regulated genes, but the magnitude of augmentation varied between genes. This variation can be explained by an estimated 7.5‐fold difference in sensitivities of genes to salmeterol. Deming regression analysis of the gene expression changes produced by the combination of salmeterol and RNO versus the sum of their individual effects showed a deviation away from unity slope that may be explained by a synergistic effect of RNO at some DEGs. Consistent with these results, PDE4 inhibitors, GSK 256066, and roflumilast potentiated the effects of LABAs, indacaterol, and formoterol, on a panel of randomly‐selected genes as measured by RT‐PCR.Collectively, these data suggest that PDE4 inhibition may synergistically augment LABA‐induced gene expression changes in airway epithelial cells. This interaction between LABAs and PDE4 inhibitors may contribute to the therapeutic benefits of their combination in COPD.Support or Funding InformationCanadian Institutes for Health Research (PJT 152904)This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.

On the impact of the aspect ratio on the formation of large-Scale structures in turbulent mixed convection in a cuboidal sample

Temperature measurements combined with Particle Image Velocimetry (PIV) were performed in a cuboidal convection sample with a square cross section (width / height). The objective of the study is to analyze the influence of the aspect ratio Γxz=L/H and the Archimedes number Ar on the large-scale coherent structures in mixed convection. Air at ambient pressure was used as working fluid (Pr=0.7). The aspect ratio was varied between 1 ≤ Γxz ≤ 4 (length / height) and the variation of the Archimedes number was achieved by prescribing the inflow velocity of an air jet, which was superimposed on the thermally induced flow via an inlet and outlet channel. The Rayleigh number was kept constant at Ra=2.0×108. A model, adopted from pure thermal convection, was used to extract the number of convection rolls from the circumferential temperature distribution measured along the sidewalls of the convection sample. For a fixed Archimedes number (Ar ≈ 4), the number of thermally induced large-scale circulations (LSCTC) increased with the aspect ratio of the sample. Specifically, starting with Γ=2, a linear dependence with unity slope was found. A decrease of the Archimedes number led to a transition from the single LSCTC structures to FC-dominated LSCs (LSCFC) for Γ=1 and Γ=2, whereas the multi-roll structures found for Γ=3 and Γ=4 were more stable even for higher inflow velocities.

XW-100: First FDA CLIA-Waived CBC Analyzer Designed for Physician Office Use.

The XW-100 hematology analyzer (Sysmex America) is the first complete blood count (CBC) instrument waived by the US Food and Drug Administration. This analyzer also tests for a 3-part white blood cell count differential. The XW-100 analyzer was evaluated for preanalytical specimen variables including the need for mixing, specimen storage conditions, freeze-thaw cycles, the effect of under filling of tubes, precision, linearity, carryover, limits of the blank, detection, and quantification and interferences from common and CBC-specific substances. The clinical study examined 586 blood samples from 6 CLIA-waived clinical sites and 6 paired moderately complex sites. The point-of-care sites had different medical specialties and were using inexperienced operators. The results of 8 measurements and 4 calculated parameters were compared to a moderately complex point-of-care hematology analyzer (pocH-100i, Sysmex). The precision was <6% for all analytics, and there was no carryover noted. Samples containing interfering substances were appropriately flagged or suppressed by the instrument. The correlation to the predicate analyzer was highly concordant, producing near unity slope and intercept and minimal bias. Delays from sample collection to testing resulted in decreased performance. The percentage of samples inside the allowable error was >98.8% for all parameters studied. This CLIA-waived hematology analyzer produces acceptable results and can be used in offices and clinics.