Cognitive load estimation in VR flight simulator

This paper discusses the design and development of a low-cost virtual reality (VR) based flight simulator with cognitive load estimation feature using ocular and EEG signals.  Focus is on exploring methods to evaluate pilot’s interactions with aircraft by means of quantifying pilot’s perceived cognitive load under different task scenarios. Realistic target tracking and context of the battlefield is designed in VR. Head mounted eye gaze tracker and EEG headset are used for acquiring pupil diameter, gaze fixation, gaze direction and EEG theta, alpha, and beta band power data in real time. We developed an AI agent model in VR and created scenarios of interactions with the piloted aircraft. To estimate the pilot’s cognitive load, we used low-frequency pupil diameter variations, fixation rate, gaze distribution pattern, EEG signal-based task load index and EEG task engagement index. We compared the physiological measures of workload with the standard user’s inceptor control-based workload metrics. Results of the piloted simulation study indicate that the metrics discussed in the paper have strong association with pilot’s perceived task difficulty

Identifying the Binding Residues on CYP3A4 to Naringin using Protein Modeling and Docking

Cytochrome (CYP) enzymes are a superfamily of monooxygenase hemoprotein enzymes that are found throughout the body but are heavily concentrated in the endoplasmic reticulum and mitochondria of liver cells. These enzymes catalyze reactions that modify a wide range of substrates into more hydrophilic and, therefore, more readily excreted forms. Cytochrome enzymes are heavily involved in the detoxification process of many medically relevant drugs. As such, the inhibition and activation of these enzymes can substantially alter the effective bioavailability of medications and can introduce additional variables or modifiable variables into a pharmacological-based treatment. Cytochrome p450 3A4 (CYP3A4) is one of the most abundant cytochrome enzymes and can target a wide range of substrates, including many medically relevant drugs. Inhibition of CYP3A4 can increase the bioavailability and duration of the availability of a medication in the bloodstream. This makes the factors associated with the inhibition and activation of CYP3A4 of great medical interest and importance. CYP3A4 has been noted to be inhibited by naringin, a flavanone found in grapefruits and other citrus fruits. However, the characteristics of naringin binding to CYP3A4 are unknown. The residues at which naringin binds to CYP3A4 were identified using 3-D protein modeling and computerized molecular docking simulations. The PDB file for the CYP3A4 enzyme (8DYC) was obtained from the RCSB Protein Data Bank and was manipulated to remove the substrates, leaving only the prosthetic heme group. The binding between CYP3A4 and different inhibitors was studied in the literature to identify specific features of the CYP3A4 protein. The residues that form the opening of the protein cleft, the area where the substrates bind and the residues that form the active site of the enzyme were noted for reference for the docked position of naringin. PyRx was used to conduct molecular docking simulations to predict the location of naringin binding in the CYP3A4 structure. However, due to computational limitations, the docking did not predict interactions with the HEME group. Rather the final docked structure of naringin to the CYP3A4 enzyme was produced using the coordinates of the docked naringin and the HEME-containing structure of CYP3A4. The Contacts/Clashes functionality in USCF Chimera was used to identify the specific residues on the surface of the protein and these residues were compared to those identified through the literature consulted. The residues of CYP3A4 that are involved in binding naringin that were identified through this process were: Glu 374, Arg 372, Arg 106, Arg 105, Ala 370, Phe 215, Arg 212, Phe 304, Leu 482, Ser 119, Ile 223, Thr 224. Of these, Arg 372 and Thr 224 were also noted in the literature to be involved in forming the opening of the cavity in the protein. The residues Glu 374, Arg 106, Arg 105, Ala 370, Phe 215, Arg 212, Phe 304, and Ser 119 were also noted in the literature and are likely involved in forming the active site. The residues Ile 223 and Leu 482 were not noted in the works consulted and may represent additional or potentially novel residues that may be involved in the inhibition of CYP3A4. Overall, the results of the molecular docking suggest that naringin inhibits CYP3A4 by binding and blocking both the opening of the cleft within which the substrate binds and binding to residues in the active site of CYP3A4.https://nsuworks.nova.edu/protein_modeling_reports/1015/thumbnail.jp

OCCLUSION IN IMPLANT-AT A GLANCE

Objectives: Occlusion is a critical and very important component for the clinical success and longevity of dental implants. This review article focuses on the various aspects of implant protective occlusion. Our scientific literature regarding implant occlusion, particularly in implant-supported fixed dental prostheses remains controversial.Materials and methods: A search strategy was performed in MEDLINE/PubMed, Scopus and Google Scholar with keywords – ‘implants’ and ‘occlusion’, ‘implants’ and ‘fixed prosthesis, ‘implants’ and ‘fixed dental prostheses’, ‘implants’ and ‘partial edentulism’, ‘implants’ and ‘complications’, ‘implants’ and ‘failures’, ‘implants’ and ‘cantilever’, ‘implants’ and ‘occlusal load’.Results: 135 articles were retrieved. After hand search a total of 290 articles were identified. Ultimately, 30 articles were selected and summarized and discussed as they met the selection criteria.Conclusion: Most of the available clinical data are controversial. Implant-protected occlusion can be accomplished by decreasing the width of the occlusal table and improving the direction of force. By doing these things, we can minimize overload on bone-implant interfaces and implant prostheses, to maintain an implant load within the physiological limits of individualized occlusion, and ultimately provide long-term stability of implants and implant prostheses. Current clinical practices rely heavily on principles extracted from the natural dentition or removable dental prostheses on complete edentulous patients and on expert opinions

Role of invasive mechanical ventilation and ECMO in the management of COVID-19: a systematic review

Objectives: This systematic review aims to provide insight into the outcome of extracorporeal membrane oxygenation (ECMO) and invasive mechanical ventilation use in critically ill COVID-19 patients. Data sources: Electronic databases PubMed Central and PubMed were searched from January 2020 to June 2020 for published studies about ECMO and/or invasive mechanical ventilation use in COVID-19 patients. Data Extraction and Study Selection: The search strategy retrieved 766 articles, of which 19 studies consisting of 204 patients fulfilled the inclusion criteria and were included in the analysis. Data synthesis: Primary outcomes evaluated were discharge and/or clinical improvement and mortality rate. Secondary outcomes evaluated included reported complications and the mean number of days of hospitalization for survivors. Weighted averages of included studies were calculated, and data were pooled in forest plots. Nearly, 68.1% of the patients received invasive mechanical ventilation without ECMO support, and 31.9% were placed on ECMO. Also, 22.5% of the patients were discharged and/or clinically improved and 51.5% died. Twenty-six percent of the study population deteriorated but remained alive or experienced no improvement in clinical condition. And 75.2% of those who died belonged to the non-ECMO group and 24.8% to the ECMO group. The mortality rate in the non-ECMO group was 56.8% compared to 40% in the ECMO group. Conclusion: The utility of ECMO during a pandemic is uncertain as it is a resource-intensive modality, especially when the mortality rate in severely ill patients infected with COVID-19 virus is already known to be high

DPY30 loss leads to DNA re-replication and immunoediting in pancreatic ductal adenocarcinoma

View full abstracthttps://openworks.mdanderson.org/leading-edge/1036/thumbnail.jp

Postoperative Discharge Destination Impacts 30-Day Outcomes: A National Surgical Quality Improvement Program Multi-Specialty Surgical Cohort Analysis

Surgical patients can be discharged to a variety of facilities which vary widely in intensity of care. Postoperative readmissions have been found to be more strongly associated with post-discharge events than pre-discharge complications, indicating the importance of discharge destination. We sought to evaluate the association between discharge destination and 30-day outcomes. A retrospective cohort study was conducted using the American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) database. Patients were dichotomized based on discharge destination: home versus non-home. The main outcome of interest was 30-day unplanned readmission. The secondary outcomes included post-discharge pulmonary, infectious, thromboembolic, and bleeding complications, as well as death. In this cohort study of over 1.5 million patients undergoing common surgical procedures across eight surgical specialties, we found non-home discharge to be associated with adverse 30-day post-operative outcomes, namely, unplanned readmissions, post-discharge pulmonary, infectious, thromboembolic, and bleeding complications, as well as death. Non-home discharge is associated with worse 30-day outcomes among patients undergoing common surgical procedures. Patients and caregivers should be counseled regarding discharge destination, as non-home discharge is associated with adverse post-operative outcomes

A Search for Technosignatures Around 31 Sun-like Stars with the Green Bank Telescope at 1.15-1.73 GHz

We conducted a search for technosignatures in April of 2018 and 2019 with the L-band receiver (1.15-1.73 GHz) of the 100 m diameter Green Bank Telescope. These observations focused on regions surrounding 31 Sun-like stars near the plane of the Galaxy. We present the results of our search for narrowband signals in this data set as well as improvements to our data processing pipeline. Specifically, we applied an improved candidate signal detection procedure that relies on the topographic prominence of the signal power, which nearly doubles the signal detection count of some previously analyzed data sets. We also improved the direction-of-origin filters that remove most radio frequency interference (RFI) to ensure that they uniquely link signals observed in separate scans. We performed a preliminary signal injection and recovery analysis to test the performance of our pipeline. We found that our pipeline recovers 93% of the injected signals over the usable frequency range of the receiver and 98% if we exclude regions with dense RFI. In this analysis, 99.73% of the recovered signals were correctly classified as technosignature candidates. Our improved data processing pipeline classified over 99.84% of the ~26 million signals detected in our data as RFI. Of the remaining candidates, 4539 were detected outside of known RFI frequency regions. The remaining candidates were visually inspected and verified to be of anthropogenic nature. Our search compares favorably to other recent searches in terms of end-to-end sensitivity, frequency drift rate coverage, and signal detection count per unit bandwidth per unit integration time.Comment: 20 pages, 8 figures, in press at the Astronomical Journal (submitted on Sept. 9, 2020; reviews received Nov. 6; re-submitted Nov. 6; accepted Nov. 17

LEARN: A multi-centre, cross-sectional evaluation of Urology teaching in UK medical schools

OBJECTIVE: To evaluate the status of UK undergraduate urology teaching against the British Association of Urological Surgeons (BAUS) Undergraduate Syllabus for Urology. Secondary objectives included evaluating the type and quantity of teaching provided, the reported performance rate of General Medical Council (GMC)-mandated urological procedures, and the proportion of undergraduates considering urology as a career. MATERIALS AND METHODS: LEARN was a national multicentre cross-sectional study. Year 2 to Year 5 medical students and FY1 doctors were invited to complete a survey between 3rd October and 20th December 2020, retrospectively assessing the urology teaching received to date. Results are reported according to the Checklist for Reporting Results of Internet E-Surveys (CHERRIES). RESULTS: 7,063/8,346 (84.6%) responses from all 39 UK medical schools were included; 1,127/7,063 (16.0%) were from Foundation Year (FY) 1 doctors, who reported that the most frequently taught topics in undergraduate training were on urinary tract infection (96.5%), acute kidney injury (95.9%) and haematuria (94.4%). The most infrequently taught topics were male urinary incontinence (59.4%), male infertility (52.4%) and erectile dysfunction (43.8%). Male and female catheterisation on patients as undergraduates was performed by 92.1% and 73.0% of FY1 doctors respectively, and 16.9% had considered a career in urology. Theory based teaching was mainly prevalent in the early years of medical school, with clinical skills teaching, and clinical placements in the later years of medical school. 20.1% of FY1 doctors reported no undergraduate clinical attachment in urology. CONCLUSION: LEARN is the largest ever evaluation of undergraduate urology teaching. In the UK, teaching seemed satisfactory as evaluated by the BAUS undergraduate syllabus. However, many students report having no clinical attachments in Urology and some newly qualified doctors report never having inserted a catheter, which is a GMC mandated requirement. We recommend a greater emphasis on undergraduate clinical exposure to urology and stricter adherence to GMC mandated procedures

Spectacular Nucleosynthesis from Early Massive Stars

Stars that formed with an initial mass of over 50 M ⊙ are very rare today, but they are thought to be more common in the early Universe. The fates of those early, metal-poor, massive stars are highly uncertain. Most are expected to directly collapse to black holes, while some may explode as a result of rotationally powered engines or the pair-creation instability. We present the chemical abundances of J0931+0038, a nearby low-mass star identified in early follow-up of the SDSS-V Milky Way Mapper, which preserves the signature of unusual nucleosynthesis from a massive star in the early Universe. J0931+0038 has a relatively high metallicity ([Fe/H] = −1.76 ± 0.13) but an extreme odd–even abundance pattern, with some of the lowest known abundance ratios of [N/Fe], [Na/Fe], [K/Fe], [Sc/Fe], and [Ba/Fe]. The implication is that a majority of its metals originated in a single extremely metal-poor nucleosynthetic source. An extensive search through nucleosynthesis predictions finds a clear preference for progenitors with initial mass >50 M ⊙, making J0931+0038 one of the first observational constraints on nucleosynthesis in this mass range. However, the full abundance pattern is not matched by any models in the literature. J0931+0038 thus presents a challenge for the next generation of nucleosynthesis models and motivates the study of high-mass progenitor stars impacted by convection, rotation, jets, and/or binary companions. Though rare, more examples of unusual early nucleosynthesis in metal-poor stars should be found in upcoming large spectroscopic surveys