Herpes zoster on the forehead masquerading as an abscess complication to look out for: a case report

Herpes zoster or shingles is caused by the reactivation of latent varicella zoster virus (VZV) infection within the sensory ganglia. Primary VZV infection results in varicella (chickenpox) usually in childhood, characterized by vesicular lesions on the face, trunk, and extremities. Although herpes zoster can occur at any age, it is mainly a disease of adults over age 50 and/or immunocompromised individuals. Complications of herpes zoster include post herpetic neuralgia, herpes zoster ophthalmic us and less commonly acute retinal necrosis, aseptic meningitis, and encephalitis. Here we present the case of a 51-year-old female patient with Herpes Zoster infection involving the dermatome on the forehead, initially misdiagnosed, to alert clinicians to create awareness and minimize misdiagnosis of other patients with similar cases. It is unusual to find patients presenting with infection involving the dermatome of the forehead.

Statistical models to provide meaningful information to GNSS users in the presence of ionospheric scintillation

Ionospheric scintillation is one of the most challenging problems in Global Navigation Satellite Systems (GNSS) positioning and navigation. Scintillation occurrence can not only lead to an increase in the probability of losing the GNSS signal lock but also reduce the precision of the pseudorange and carrier phase measurements, thus leading to positioning accuracy degradation. Statistical models developed to estimate the probability of loss of lock and Geometric Dilution of Precision normalized 3D positioning errors as a function of scintillation levels are presented. The models were developed following the statistical approach of non-linear regression on data recorded by Ionospheric Scintillation Monitoring Receivers operational at high and low latitudes. The validation of the probability of loss of lock models indicated average correlation coefficient values above 0.7 and average Root Mean Squared Error (RMSE) values below 0.35. The validation of the positioning error models indicated average RMSE values below 10 cm. The good performance of the developed models indicates that these can provide GNSS users with information on the satellite loss of lock probability and the error in the 3D position under scintillation

Analysis of the relationship between scintillation parameters, multipath and ROTI

© 2020 by the authors. Licensee MDPI, Basel, Switzerland. Global Navigation Satellite System (GNSS) operation can be affected by several environmental factors, of which ionospheric scintillation is one of the most significant. Scintillation is usually characterized by two indices, namely the amplitude scintillation index (S4) and phase scintillation index (σφ). However, these two indices can only be generated by specialized GNSS receivers, which are not widely available all around the world. To popularize the study of scintillation, this article proposes to use more accessible parameters, namely multipath (MP) and rate of change of total electron content index (ROTI), to characterize scintillation. Using GPS data obtained on six days in total from three stations, namely PRU2 and SAO0P located in Sao Paulo, Brazil and SNA0P located in Antarctica, respectively, both the time series plots and 2D maps were generated to investigate the relationship of scintillation indices (S4 and σφ) with MP and ROTI. To prevent the effect of the real multipath error, a 30-degree satellite elevation mask is applied to all the data. As the scintillation indices S4 and σφ have a sampling interval of 1 min, MP and ROTI are calculated with the same sampling interval for a more direct comparison. The results show that the structural similarity (SSIM) and correlation coefficient (CC) between parameters was greater than 0.7 for 70% of outputs. In addition, the variogram and cross-variogram are applied to investigate the spatial structure of the MP, ROTI, S4 and σφ in order to support the results of SSIM and CC. With outputs in three forms, promising spatial and temporal relationships between parameters was observed

Molecular dynamic simulation on temperature evolution of SiC under directional microwave radiation

Silicon carbide (SiC) is widely used as the substrate for high power electronic devices as well as susceptors for microwave (MW) heating. The dynamics of microwave interaction with SiC is not fully understood, especially at the material boundaries. In this paper, we used the molecular dynamics simulation method to study the temperature evolution during the microwave absorption of SiC under various amplitudes and frequencies of the microwave electric field. Directional MW heating of a SiC crystal slab bounded by surfaces along [100] crystallographic direction shows significantly faster melting when the field is applied parallel to the surface compared to when applied perpendicular

Effects of GNSS receiver tuning on the PLL tracking jitter estimation in the presence of ionospheric scintillation

Ionospheric scintillation is an interference characterized by rapid and random fluctuations inradio frequency signals when passing through irregularities in the ionosphere. It can severely degrade theperformance of Global Navigation Satellite System (GNSS) receivers, thus increasing positioning errors.Receivers with different tracking loop bandwidths and coherent integration times perform differently underscintillation. This study investigates the effects of GNSS receiver tracking loop tuning on scintillationmonitoring and Phase Locked Loop (PLL) tracking jitter estimation using simulated GNSS data. Thevariation of carrier to noise density ratio (C/N0) under scintillation with different tracking loop settings isalso studied. The results show that receiver tuning has a minor effect on scintillation indices calculation.The levels of C/N0 are also similar for different PLL bandwidths and integration times. Additionally, thetracking jitter is estimated by theoretical equations and verified using the relationship with the PLLdiscriminator output noise, which is calculated using the post‐correlation measurements. Novel approachesare further proposed to calculate 1‐s scintillation index, which enables to compute the tracking jitter ata rate of 1 s. It is found that 1‐s tracking jitter can successfully represent the signal fluctuations levels causedby scintillation. This work is valuable for developing scintillation sensitive tracking error models and is alsoof great significance for GNSS receiver design to mitigate scintillation effects

Comparative expression profiling and sequence characterization of ATP1A1 gene associated with heat tolerance in tropically adapted cattle

Climate change is an imminent threat to livestock production. One adaptation strategy is selection for heat tolerance. While it is established that the ATP1A1 gene and its product play an important role in the response to many stressors, there has been no attempt to characterize the sequence or to perform expression profiling of the gene in production animals. We undertook a field experiment to compare the expression profiles of ATP1A1 in heat-tolerant Vechur and Kasaragod cattle (Bos taurus indicus) with the profile of a heat-susceptible crossbreed (B. t. taurus × B. t. indicus). The cattle were exposed to heat stress while on pasture in the hot summer season. The environmental stress was quantified using the temperature humidity index (THI), while the heat tolerance of each breed was assessed using a heat tolerance coefficient (HTC). The ATP1A1 mRNA of Vechur cattle was amplified from cDNA and sequenced. The HTC varied significantly between the breeds and with time-of-day (p < 0.01). The breed–time-of-day interaction was also significant (p < 0.01). The relative expression of ATP1A1 differed between heat-tolerant and heat-susceptible breeds (p = 0.02). The expression of ATP1A1 at 08:00, 10:00 and 12:00, and the breed–time-of-day interaction, were not significant. The nucleotide sequence of Vechur ATP1A1 showed 99% homology with the B. t. taurus sequence. The protein sequence showed 98% homology with B. t. taurus cattle and with B. grunniens (yak) and 97.7% homology with Ovis aries (sheep). A molecular clock analysis revealed evidence of divergent adaptive evolution of the ATP1A1 gene favoring climate resilience in Vechur cattle. These findings further our knowledge of the relationship between the ATP1A1 gene and heat tolerance in phenotypically incongruent animals. We propose that ATP1A1 could be used in marker assisted selection (MAS) for heat tolerance

Methodological approaches for assessing certainty of the evidence in umbrella reviews: A scoping review

INTRODUCTION: The number of umbrella reviews (URs) that compiled systematic reviews and meta-analysis (SR-MAs) has increased dramatically over recent years. No formal guidance for assessing the certainty of evidence in URs of meta-analyses exists nowadays. URs of non-interventional studies help establish evidence linking exposure to certain health outcomes in a population. This study aims to identify and describe the methodological approaches for assessing the certainty of the evidence in published URs of non-interventions. METHODS: We searched from 3 databases including PubMed, Embase, and The Cochrane Library from May 2010 to September 2021. We included URs that included SR-MAs of studies with non-interventions. Two independent reviewers screened and extracted data. We compared URs characteristics stratified by publication year, journal ranking, journal impact factor using Chi-square test. RESULTS: Ninety-nine URs have been included. Most were SR-MAs of observational studies evaluating association of non-modifiable risk factors with some outcomes. Only half (56.6%) of the included URs assessed the certainty of the evidence. The most frequently used criteria is credibility assessment (80.4%), followed by GRADE approach (14.3%). URs published in journals with higher journal impact factor assessed certainty of evidence than URs published in lower impact group (77.1 versus 37.2% respectively, p < 0.05). However, criteria for credibility assessment used in four of the seven URs that were published in top ranking journals were slightly varied. CONCLUSIONS: Half of URs of MAs of non-interventional studies have assessed the certainty of the evidence, in which criteria for credibility assessment was the commonly used method. Guidance and standards are required to ensure the methodological rigor and consistency of certainty of evidence assessment for URs

Opportunities for seagrass research derived from remote sensing : a review of current methods

Seagrass communities provide critical ecosystem and provisioning services for both human populations and a wide range of associated species globally. However, it has been reported that seagrass area is decreasing at a rapid rate in many parts of the world, mostly due to anthropogenic activities including global change (pollution and climate change). The aim of this review article is to highlight the range of current tools for studying seagrasses as well as identify the benefits and limitations of a range of remote sensing and traditional methodologies. This paper provides a discussion of the ecological importance of seagrass meadows, and recent trends and developments in seagrass research methods are discussed including the use of satellite images and aerial photographs for seagrass monitoring and various image processing steps that are frequently utilised for seagrass mapping. The extensive use of various optical, Radar and LiDAR data for seagrass research in recent years has also been described in detail. The review concludes that the recent explosion of new methods and tools available from a wide range of platforms combined with the recent recognition of the importance of seagrasses provides the research community with an excellent opportunity to undertake a range of timely research. This research should include mapping the extent and distribution of seagrasses, identifying the drivers of change and factors that confer resilience, as well as quantification of the ecosystem services provided. Whilst remotely sensed data provides an important new tool it should be used in conjunction with traditional methods for validation and with a knowledge of the limitations of results and careful interpretation

Kaposi's Sarcoma-Associated Herpesvirus Forms a Multimolecular Complex of Integrins ( V 5, V 3, and 3 1) and CD98-xCT during Infection of Human Dermal Microvascular Endothelial Cells, and CD98-xCT Is Essential for the Postentry Stage of Infection

Kaposi's sarcoma-associated herpesvirus (KSHV) interacts with cell surface heparan sulfate (HS) and α3β1 integrin during the early stages of infection of human dermal microvascular endothelial cells (HMVEC-d) and human foreskin fibroblasts (HFF), and these interactions are followed by virus entry overlapping with the induction of preexisting host cell signal pathways. KSHV also utilizes the amino acid transporter protein xCT for infection of adherent cells, and the xCT molecule is part of the cell surface heterodimeric membrane glycoprotein CD98 (4F2 antigen) complex known to interact with α3β1 and αVβ3 integrins. KSHV gB mediates adhesion of HMVEC-d, CV-1, and HT-1080 cells and HFF via its RGD sequence. Anti-αV and -β1 integrin antibodies inhibited the cell adhesion mediated by KSHV-gB. Variable levels of neutralization of HMVEC-d and HFF infection were observed with antibodies against αVβ3 and αVβ5 integrins. Similarly, variable levels of inhibition of virus entry into adherent HMVEC-d, 293 and Vero cells, and HFF was observed by preincubating virus with soluble α3β1, αVβ3, and αVβ5 integrins, and cumulative inhibition was observed with a combination of integrins. We were unable to infect HT1080 cells. Virus binding and DNA internalization studies suggest that αVβ3 and αVβ5 integrins also play roles in KSHV entry. We observed time-dependent temporal KSHV interactions with HMVEC-d integrins and CD98/xCT with three different patterns of association and dissociation. Integrin αVβ5 interaction with CD98/xCT predominantly occurred by 1 min postinfection (p.i.) and dissociated at 10 min p.i., whereas α3β1-CD98/xCT interaction was maximal at 10 min p.i. and dissociated at 30 min p.i., and αVβ3-CD98/xCT interaction was maximal at 10 min p.i. and remained at the observed 30 min p.i. Fluorescence microscopy also showed a similar time-dependent interaction of αVβ5-CD98. Confocal-microscopy studies confirmed the association of CD98/xCT with α3β1 and KSHV. Preincubation of KSHV with soluble heparin and α3β1 significantly inhibited this association, suggesting that the first contact with HS and integrin is an essential element in subsequent CD98-xCT interactions. Anti-CD98 and xCT antibodies did not block virus binding and entry and nuclear delivery of viral DNA; however, viral-gene expression was significantly inhibited, suggesting that CD98-xCT play roles in the post-entry stage of infection, possibly in mediating signal cascades essential for viral-gene expression. Together, these studies suggest that KSHV interacts with functionally related integrins (αVβ3, α3β1, and αVβ5) and CD98/xCT molecules in a temporal fashion to form a multimolecular complex during the early stages of endothelial cell infection, probably mediating multiple roles in entry, signal transduction, and viral-gene expression