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This article provides an introduction to randomized response polling, a technique which was designed to allow for questioning on sensitive issues while protecting the respondent's privacy and avoiding social desirability bias. It is described in terms that are suitable for presentation and use in any classroom environment. Instructions for plain users are included, along with the results of a small in-class implementation. The underpinnings of the method, which are laid out for the statistically savvy, illustrate the tradeoff between data acquisition and privacy protection. A few suitable references are also included for those who wish to dig further into the subject. Supplementary materials for this article are available online.

Analyses of hourly radiosonde data of temperature, wind, and relative humidity during four days (two with convection and two with no convection) as a part of an intensive observation period in CPEA-2 campaign over Koto Tabang (100.32° E, 0.20° S), Indonesia, are presented. Characteristics of gravity waves in terms of dominant wave frequencies at different heights and their vertical wavelengths are shown in the lower stratosphere during a convective and non-convective period. Gravity waves with periods ~10 h and ~4–5 h were found dominant near tropopause (a region of high stability) on all days of observation. Vertical propagation of gravity waves were seen modified near heights of the three identified strong wind shears (at ~16, 20, and 25 km heights) due to wave-mean flow interaction. Between 17 and 21 km heights, meridional wind fluctuations dominated over zonal wind, whereas from 22 to 30 km heights, wave fluctuations with periods ~3–5 h and ~8–10 h in zonal wind and temperature were highly associated, suggesting zonal orientation of wave propagation. Gravity waves from tropopause region to 30 km heights were analyzed. In general, vertical wavelength of 2–5 km dominated in all the mean-removed (~ weekly mean) wind and temperature hourly profiles. Computed vertical wavelength spectra are similar, in most of the cases, to the source spectra (1–16 km height) except that of zonal wind spectra, which is broad during active convection. Interestingly, during and after convection, gravity waves with short vertical wavelength (~2 km) and short period (~2–3 h) emerged, which were confined in the close vicinity of tropopause, and were not identified on non-convective days, suggesting convection to be the source for them. Some wave features near strong wind shear (at 25 km height) were also observed with short vertical wavelengths in both convective and non-convective days, suggesting wind shear to be the sole cause of generation and seemingly not associated with deep convection below. A drop in the temperature up to ~4–5 K (after removal of diurnal component) was observed at ~16 km height near a strong wind shear (~45–55 m s−1 km−1) during active period of convection.

Little is known about the durability of plasmid DNA transgene expression in mammalian cells in the absence of growth selection. For this purpose, we have begun the study of liposomal transfer and expression of plasmid DNA encoding green fluorescent protein (GFP) in human erythroleukemia K562 cells. Detection and selection of GFP expression were accomplished visually and by flow cytometry. GFP expression was noticeable in cells within 4 h of transfection. In nine separate transfections, approximately 20% of the transfected cells expressed GFP with a mean fluorescence 40–50× that of control cells (15 fluorescent units [FU] vs. 0.3 FU) during the first five days after transfection. The percentage of GFP positive cells dropped rapidly to 0.1% by day 14 post-transfection, but fluorescence activated cell sorting on this day resulted in the identification of stable transfectants expressing GFP for an additional 6–12 months in culture. GFP expression is adequate for the identification, isolation and monitoring of stable transfection events after lipid-mediated transfection of eukaryotic cells.

Abstract Background Abnormal DNA methylation is thought to contribute to the onset and progression of systemic sclerosis. Currently, the most comprehensive assay for profiling DNA methylation is whole-genome bisulfite sequencing (WGBS), but its precision depends on read depth and it may be subject to sequencing errors. SOMNiBUS, a method for regional analysis, attempts to overcome some of these limitations. Using SOMNiBUS, we re-analyzed WGBS data previously analyzed using bumphunter, an approach that initially fits single CpG associations, to contrast DNA methylation estimates by both methods. Methods Purified CD4+ T lymphocytes of 9 SSc and 4 control females were sequenced using WGBS. We separated the resulting sequencing data into regions with dense CpG data, and differentially methylated regions (DMRs) were inferred with the SOMNiBUS region-level test, adjusted for age. Pathway enrichment analysis was performed with ingenuity pathway analysis (IPA). We compared the results obtained by SOMNiBUS and bumphunter. Results Of 8268 CpG regions of ≥ 60 CpGs eligible for analysis with SOMNiBUS, we identified 131 DMRs and 125 differentially methylated genes (DMGs; p-values less than Bonferroni-corrected threshold of 6.05–06 controlling family-wise error rate at 0.05; 1.6% of the regions). In comparison, bumphunter identified 821,929 CpG regions, 599 DMRs (of which none had ≥ 60 CpGs) and 340 DMGs (q-value of 0.05; 0.04% of all regions). The top ranked gene identified by SOMNiBUS was FLT4, a lymphangiogenic orchestrator, and the top ranked gene on chromosome X was CHST7, known to catalyze the sulfation of glycosaminoglycans in the extracellular matrix. The top networks identified by IPA included connective tissue disorders. Conclusions SOMNiBUS is a complementary method of analyzing WGBS data that enhances biological insights into SSc and provides novel avenues of investigation into its pathogenesis.

The strong dependency of the free-space optical (FSO) communication systems on the line-of-sight link put forward an inevitable challenge. Motivated by this fact, in this work, we aim to present and analyze a practical approach to model and design the intelligent reflecting surface (IRS)-assisted FSO communication system incorporating the impact of random misalignment. Contrary to the existing literature, an insightful IRS-assisted FSO model is proposed to envision the impact of the crucial system parameters. To this end, we propose a geometric and misalignment loss (GML) model that incorporates the random statistical modeling of the angle of incidence and the angle of reflection corresponding to the transmitted laser beam. Therefore, the proposed GML model allows us to inspect a realistic transmission and reception scenario of an IRS-assisted FSO system. Moreover, unlike the existing works, we consider independent fading statistics between the laser source (transmitter)-IRS link and IRS-photodetector (receiver) link. All these considerations allow us to envision the performance of a practical IRS-assisted FSO system. Several analytical closed-form expressions corresponding to the statistical distribution functions concerning the proposed GML model are also derived. Our derived closed-form expressions can be used as mathematical tools to examine the performance of an IRS-assisted FSO system under random misalignment. Further, our key findings indicate that under the impact of the random misalignment, the non-orthogonality of the lens with respect to the beam-line significantly impacts the system performance. Furthermore, simulation results validate the presented analysis and reveal unprecedented insights for the proposed IRS-assisted FSO system design.

Optical coherence tomography (OCT) is a non-invasive tool to measure thickness of various layers of retina. Recently, retinal nerve fibre layer (RNFL) and ganglion cell and inner plexiform layer (GCIP) thinning has been observed in OCT in patients with multiple sclerosis (MS) and neuromyelitis optica spectrum disorder (NMOSD), This study compared OCT profile, along with visual acuity (VA), color vision (CV), contrast saturation (CS) and visual evoked potentials (VEP) in two main cohorts of MS and NMOSD and with controls, during acute episode of optic neuritis (ON), at 3 and 6 months.We found that changes of ON were present in 75% of MS eyes and in 45% of NMOSD patients. Of these, subclinical involvement was present in 56.25% of MS eyes and only in 5% of NMOSD eyes suggesting frequent subclinical involvement in the former. Mean RNFL was 95.23 ± 15.53 in MS and 66.14 ± 43.73 in NMOSD after 6 months of ON episode. Thinning of NQ and IQ was observed in NMOSD eyes in the immediate period after ON attack. At 6 months relative sparing of RNFL in TQ was observed in NMOSD ON eyes and MS ON showed predilection for involvement of TQ.

Abstract Considering the emergence of SARS-CoV-2 variants and low vaccine access and uptake, minimizing human interactions remains an effective strategy to mitigate the spread of SARS-CoV-2. Using a functional principal component analysis, we created a multidimensional mobility index (MI) using six metrics compiled by SafeGraph from all counties in Illinois, Ohio, Michigan and Indiana between January 1 to December 8, 2020. Changes in mobility were defined as a time-updated 7-day rolling average. Associations between our MI and COVID-19 cases were estimated using a quasi-Poisson hierarchical generalized additive model adjusted for population density and the COVID-19 Community Vulnerability Index. Individual mobility metrics varied significantly by counties and by calendar time. More than 50% of the variability in the data was explained by the first principal component by each state, indicating good dimension reduction. While an individual metric of mobility was not associated with surges of COVID-19, our MI was independently associated with COVID-19 cases in all four states given varying time-lags. Following the expiration of stay-at-home orders, a single metric of mobility was not sensitive enough to capture the complexity of human interactions. Monitoring mobility can be an important public health tool, however, it should be modelled as a multidimensional construct.

Abstract Index modulation utilizes spatial dimensions for transmission of information in multiple‐input multiple‐output (MIMO) molecular communication systems. Molecular space shift keying (MSSK) is an IM‐based technique that modulates information in the antenna index and efficiently combats both intersymbol interference and interlink interference in molecular MIMO systems. In this paper, generalized form of the MSSK scheme, that is, generalized MSSK (GMSSK) is proposed which activates a fixed number of antennas for information transmission. The antenna constellation is selected judiciously to minimize the chances of errors in the proposed GMSSK strategy. Design guidelines are provided for the GMSSK antenna constellation for the case of two activated antennas at the transmitter side. Exploiting an additional degree of freedom, the presented GMSSK scheme is shown to achieve reasonably close or better error performance with a smaller antenna array size as compared to the traditional MSSK scheme.

Purpose: To compare the optical coherence tomography (OCT)-based retinal nerve fiber layer (RNFL) and ganglion cell layer (GCL) thickness at the posterior pole, and total macular thickness of women with the polycystic ovarian syndrome (PCOS) versus healthy reproductive age group females. Methods: The study included 110 eyes of 55 diagnosed cases of PCOS (study group) and 110 eyes of 55 healthy reproductive age group (15–49 years) females (control group). All patients underwent a detailed ophthalmological evaluation followed by an OCT to measure their retinal thicknesses. The body mass index (BMI) of patients was noted and compared with the retinal thickness. Also, the lipid profile and serum testosterone levels of PCOS patients were recorded. Results: The retinal thicknesses in the two study were similar and there was no statistically significant difference. However, on stratification with BMI, it was seen that in patients with BMI>30 kg/m2, the superior Retinal Nerve Fibre Layer (RNFL) was significantly thicker in the PCOS group as compared with the control group (P = 0.0006). The mean serum testosterone level in patients with PCOS was 141.3 ± 23.2. Also, 65.45% of patients had a serum testosterone level of more than 70 ng/dL. The mean HDL cholesterol in patients with PCOS was 38.1 ± 15.6. The mean LDL cholesterol in PCOS patients was 98.4 ± 21.7, and the mean total cholesterol in PCOS patients was 153.6 ± 27.3. Conclusion: Androgens have a trophic action on nerves, which could explain the increased RNFL thickness in these patients.

In this paper, we introduce the concept of buffer-aided cooperative relaying for a free-space optical (FSO) communication system. The proposed FSO system consists of $K$ decode-and-forward(DF) relays, each equipped with a buffer of size $L$. The proposed system undergoes both path loss and atmospheric turbulence (AT) induced fading, and to evaluate the system performance a weak, as well as strong AT region is considered. The Markov chain (MC) approach is used to derive the state transition matrix of the system, which is then further used to model the evolution of buffer states. Analytical expressions of the outage probability and average bit error rate (ABER) are obtained with the help of state transition matrix. The average packet delay of the system is also evaluated with the help of obtained outage probability. The performance of the considered system is analyzed for different values of $K$ and $L$. The performance is then further compared with the non-buffer-aided (NBA) cooperative relaying for FSO communication systems and it has been observed that the proposed buffer-aided FSO system significantly outperforms the NBA FSO systems for entire range of turbulence. Finally, the impact of $L$ and $K$ on the average packet delay of the system is examined.