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Background: Many postmortem studies address the cardiovascular effects of COVID-19 and provide valuable information, but are limited by their small sample size., Objectives: The aim of this systematic review is to better understand the various aspects of the cardiovascular complications of COVID-19 by pooling data from a large number of autopsy studies., Data Sources: We searched the online databases Ovid EBM Reviews, Ovid Embase, Ovid Medline, Scopus, and Web of Science for concepts of autopsy or histopathology combined with COVID-19, published between database inception and February 2021. We also searched for unpublished manuscripts using the medRxiv services operated by Cold Spring Harbor Laboratory., Study Eligibility Criteria: Articles were considered eligible for inclusion if they reported human postmortem cardiovascular findings among individuals with a confirmed SARS coronavirus type 2 (CoV-2) infection., Participants: Confirmed COVID-19 patients with post-mortem cardiovascular findings., Interventions: None., Methods: Studies were individually assessed for risk of selection, detection, and reporting biases. The median prevalence of different autopsy findings with associated interquartile ranges (IQRs)., Results: This review cohort contained 50 studies including 548 hearts. The median age of the deceased was 69 years. The most prevalent acute cardiovascular findings were myocardial necrosis (median: 100.0%; IQR, 20%-100%; number of studies = 9; number of patients = 64) and myocardial oedema (median: 55.5%; IQR, 19.5%-92.5%; number of studies = 4; number of patients = 46). The median reported prevalence of extensive, focal active, and multifocal myocarditis were all 0.0%. The most prevalent chronic changes were myocyte hypertrophy (median: 69.0%; IQR, 46.8%-92.1%) and fibrosis (median: 35.0%; IQR, 35.0%-90.5%). SARS-CoV-2 was detected in the myocardium with median prevalence of 60.8% (IQR 40.4-95.6%)., Conclusions: Our systematic review confirmed the high prevalence of acute and chronic cardiac pathologies in COVID-19 and SARS-CoV-2 cardiac tropism, as well as the low prevalence of myocarditis in COVID-19., (Copyright © 2022 European Society of Clinical Microbiology and Infectious Diseases. Published by Elsevier Ltd. All rights reserved.)

Lithium imposes several cellular effects allegedly through multiple physiological mechanisms. Membrane depolarization is a potential unifying concept of these mechanisms. Multiple inherent imperfections of classical electrophysiology limit its ability to fully explain the depolarizing effect of lithium ions; these include incapacity to explain the high resting permeability of lithium ions, the degree of depolarization with extracellular lithium concentration, depolarization at low therapeutic concentration, or the differences between the two lithium isotopes Li-6 and Li-7 in terms of depolarization. In this study, we implemented a mathematical model that explains the quantum tunneling of lithium ions through the closed gates of voltage-gated sodium channels as a conclusive approach that decodes the depolarizing action of lithium. Additionally, we compared our model to the classical model available and reported the differences. Our results showed that lithium can achieve high quantum membrane conductance at the resting state, which leads to significant depolarization. The quantum model infers that quantum membrane conductance of lithium ions emerges from quantum tunneling of lithium through the closed gates of sodium channels. It also differentiates between the two lithium isotopes (Li-6 and Li-7) in terms of depolarization compared with the previous classical model. Moreover, our study listed many examples of the cellular effects of lithium and membrane depolarization to show similarity and consistency with model predictions. In conclusion, the study suggests that lithium mediates its multiple cellular effects through membrane depolarization, and this can be comprehensively explained by the quantum tunneling model of lithium ions.

A significant percentage of security research that is conducted suffers from common issues that prevent wide-scale adoption. Common snags of such proposed methods tend to include (i) introduction of additional nodes within the communication architecture, breaking the simplicity of the typical client-server model, or fundamental restructuring of the Internet ecosystem; (ii) significant inflation of responsibilities or duties for the user and/or server operator; and (iii) adding increased risks surrounding sensitive data during the authentication process. Many schemes seek to prevent brute-forcing attacks; they often ignore either partially or holistically the dangers of other cyber-attacks such as MiTM or replay attacks. Therefore, there is no incentive to implement such proposals, and it has become the norm instead to inflate current username/password authentication systems. These have remained standard within client-server authentication paradigms, despite insecurities stemming from poor user and server operator practices, and vulnerabilities to interception and masquerades. Besides these vulnerabilities, systems which revolve around secure authentication typically present exploits of two categories; either pitfalls which allow MiTM or replay attacks due to transmitting data for authentication constantly, or the storage of sensitive information leading to highly specific methods of data storage or facilitation, increasing chances of human error. This paper proposes a more secure method of authentication that retains the current structure of accepted paradigms, but minimizes vulnerabilities which result from the process, and does not inflate responsibilities for users or server operators. The proposed scheme uses a hybrid, layered encryption technique alongside a two-part verification process, and provides dynamic protection against interception-based cyber-attacks such as replay or MiTM attacks, without creating additional vulnerabilities for other attacks such as bruteforcing. Results show the proposed mechanism outperforms not only standardized methods, but also other schemes in terms of deployability, exploit resilience, and speed.

Objective: To explore the effects of simulation training on paediatric residents' confidence and skills in managing advanced skills in critical care., Methods: The study was conducted at Alfaisal University, Riyadh, Saudi Arabia, from March to June 2016, and comprised junior residents in paediatrics. All paediatric residents (years 1 and 2) were recruited into two workshops, held one week apart. The first workshop covered lumbar puncture/ cerebrospinal fluid interpretation, oral intubation, bone marrow aspiration, and critical airway management. The second workshop covered chest tube insertion, pleural tap, insertion of central line, and arthrocentesis. The participants were surveyed using a 5-point Likert scale survey pre- and post-course, assessing their confidence. Their practical skills were assessed using a pre-objective structured clinical examination on the same day and post-course objective structured clinical examination a week later on selected skills. The outcome measures were: (1) pre-/post-course confidence rating, and (2) pre-/post-course objective structured clinical examination results. Data was analysed using SPSS 20., Results: Of the 16 participants, 8(50%) were boys and 8(50%) girls. Besides, 13(81%) residents were in year-1 and 3(19%) in year-2. Median post-course confidence level ranks for all the skills were higher (p<0.05). There was no improvement in mean pre-objective structured clinical examination scores (2.31±2.66/ 7.46±3.02) and post- objective structured clinical examination scores (22.54±4.39/ 31.85±6.90) in Year 1 residents (p<0.001)., Conclusions: Simulation course was significantly successful in improving residents' clinical skills and confidence in performing critical tasks.

This paper presents new weighted Hermite-Hadamard type inequalities for a new class of convex functions which are known as geometrically quasi-convex functions. Some applications of these results to special means of positive real numbers have also been presented. These findings have been proved to be useful for researchers working in the fields of numerical analysis and mathematical inequalities., Competing Interests: The authors declare that they have no competing interests.

Introduction: Hematospermia is an uncommon presentation of prostate cancer. Following the introduction of MRI for patients with hematospermia we evaluated its use and effect on prostate biopsy and cancer detection rates., Materials and Methods: Analysis of patients attending our outpatient department over 2 years was undertaken. Diagnostic workup included digital rectal examination and PSA. Those with abnormal findings or persisting symptoms were offered prostate biopsy. In the second year MRI became available for patients with hematospermia. Abnormal MRI or persisting symptoms were offered biopsy. We compared the frequency of prostate biopsy and cancer detection in patients undergoing MRI and those not having imaging., Results: Forty-seven patients were referred with hematospermia. Nineteen patients did not undergo MRI; four received prostate biopsy with one adenocarcinoma found. Twenty-four patients had an MRI with 17 biopsies undertaken. Three biopsies revealed adenocarcinoma. In the MRI group 71% of patients underwent prostate biopsy but only 21% from the non-MRI group (p < 0.05). Prostate cancer detection rate in the MRI group was 18% whilst in the non-MRI group was 25% (p = 0.7)., Conclusions: Our findings indicate that caution should be used with MRI as it can lead to an increase in prostate biopsy with no change in cancer detection rate.

Background: Testicular cancer is the commonest malignancy in young men. Improvements in survival rates have led to campaigns to raise awareness in at-risk men. We assessed the changing size of testicular tumours given the public health initiatives promoting testicular self-examination (TSE)., Methods: Retrospective analysis of men (≥16 years) undergoing orchidectomy for testicular cancer at our institution over two time periods (1975-85 and 2007-12) were identified using our cancer registry. Histopathology reports were used to record testicular tumour size as the maximum measured dimension. Significance was indicated by P < 0.05., Results: Of 305 orchidectomies performed, 215 had histopathology reports available. Median age was 34 years (16-75 years). Mean tumour size was 7.2 cm in 1975-85 and 4.1 cm in 2007-12 showing a significant reduction (P = 0.02). Significant reduction was seen in all age groups except >60 years. Furthermore there was a significant increase in proportion of men presenting in the youngest age group (16-29 years) in the 2007-12 cohort (43 versus 29%, P = 0.02)., Conclusion: The trend in reduction of tumour size at presentation and increased proportion of younger men presenting with testicular cancer supports an increased awareness. Promotion of TSE and public education should remain important initiatives given the increasing incidence of testicular cancer. Awareness still needs addressing in older men., (© The Author 2016. Published by Oxford University Press on behalf of Faculty of Public Health. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Dynamic Y stents are used in tracheobronchial obstruction, tracheal stenosis, and tracheomalacia. Placement may be difficult and is usually accomplished using a rigid grasping forceps (under fluoroscopic guidance) or a rigid bronchoscope. We report using a new stent placement technique on an elderly patient with a central tracheobronchial tumor. It included using a flexible bronchoscope, video laryngoscope, and laryngeal mask airway. The new technique we used has the advantages of continuous direct endoscopic visualization during stent advancement and manipulation, and securing the airways with a laryngeal mask airway at the same time. This technique eliminates the need for intraoperative fluoroscopy.

A portable luminescence spectrofluorometer weighing only 1.5 kg that uses multiple light emitting diodes (LEDs) as excitation sources was developed and evaluated. Excitation using a sequence of seven individual broad-band LED emission sources enabled the generation of excitation-emission spectra using a light weight (<1.5 kg) spectrometer. Limits of detection for rhodamine 6G, rhodamine B, and fluorescein were 2.9, 3.2, and 11.0 nM, respectively. Generation of excitation-emission matrices (EEMs) enabled the analysis of samples containing mixtures of rhodamine B and fluorescein. Buffered saline plant and animal feed extracts were also analyzed using this instrument. These samples included the woody plants Pistacia lentiscus (Evergreen pistache or Mastic) and Philyria latifolia, and the herbaceous species Medicago sativa (alfalfa), Trifolium spp. (clover), and a feed concentrate. Application of multi-way principal component analysis (MPCA) to the resulting three-dimensional data sets enabled discernment among these various diet constituents.

Photoluminescence of plant extract solutions has been investigated for discrimination of plant life forms (grasses, forbs, and shrubs) using principal component analysis (PCA). Clippings from each of six plant species representing three different plant life forms potentially found in the diets of free-ranging herbivores in the Chihuahuan Desert of North America were investigated for possible discernment. These plants included Sporobolus flexuosus (mesa dropseed, a grass), Pleuraphis mutica (tobosa, a grass), Dimorphocarpa wislizenii (spectacle pod, a forb), Sphaeralcea incana (pale globemallow, a forb), Flourensia cernua leaves (tarbush, a shrub), and Atriplex canescens leaves and stems (fourwing saltbush, a shrub). Emission spectra (370-600 nm) from phosphate buffered saline (PBS) extract solutions (pH 2.2, 7.5 and 12.5) were recorded for each plant with excitation at 365 nm. Use of PBS minimized chlorophyll interference. Discernment among plant life forms within these plant species was achieved.

The surface properties of microfluidic devices play an important role in their flow behavior. We report here on an effective control of the surface chemistry and performance of polymeric microchips through a bulk modification route during the fabrication process. The new protocol is based on modification of the bulk microchip material by tailored copolymerization of monomers during atmospheric-pressure molding. A judicious addition of a modifier to the primary monomer solution thus imparts attractive properties to the plastic microchip substrate, including significant enhancement and/or modulation of the EOF (with flow velocities comparable to those of glass), a strong pH sensitivity and high stability. Carboxy, sulfo, and amino moieties have thus been introduced (through the incorporation of methylacrylic acid, 2-sulfoethyl-methacrylate and 2-aminoethyl-methacrylate monomers, respectively). A strong increase in the electroosmotic pumping compared to the native poly(methylmethacrylate)(PMMA) microchip (ca. electroosmotic mobility increases from 2.12 to 4.30 x 10(-4) cm(2) V(-1) s(-1)) is observed using a 6% methylacrylate (MAA) modified PMMA microchip. A 3% aminoethyl modified PMMA microchip exhibits a reversal of the electroosmotic mobility (for example, -5.6 x 10(-4) cm(2) V(-1) s(-1) at pH 3.0). The effects of the modifier loading and the pH on the EOF have been investigated for the MAA-modified PMMA chips. The bulk-modified devices exhibit reproducible and stable EOF behavior. The one step fabrication/modification protocol should further facilitate the widespread production of high-performance plastic microchip devices.