Letter to the editor of Heliyon re: Design and optimization of a high efficiency CdTe-FeSi2 based double-junction two-terminal tandem solar cell. Heliyon 10 (2024) e27994.

In March 2024 - based on computer simulation - it was reported that 2-junction 1.5 eV CdTe/0.87 eV FeSi2 solar cells can achieve actual power conversion efficiency of 43.9 %, open circuit voltage of 1.928 V, and fill factor of 89.88 % at 300 K when the cells are irradiated by the air mass 1.5 global (AM1.5G) solar spectrum [M. H. Tonmoy et al., Heliyon 10 (2024) e27994]. These simulated values exceed the ideal detailed balance-limiting power conversion efficiency, open circuit voltage, and fill factor of a 1.5 eV/0.87 eV 2-junction solar cell.

Characterizing lift, drag, and pressure differences across wandering salamanders (Aneides vagrans) with computational fluid dynamics to investigate aerodynamics.

Wandering salamanders (Aneides vagrans), known to occupy the crowns of old growth coast redwood trees, have recently been found to decelerate and engage in controlled, nonvertical descent while falling. Closely related, nonarboreal species with seemingly minor morphological differences exhibit far less behavioral control while falling; however, the influence of salamander morphology on aerodynamics remains to be tested. Here, we examine differences in morphology and aerodynamics of two salamander species, A. vagrans and the nonarboreal ensatina salamander (Ensatina eschscholtzii), using a combination of traditional and contemporary techniques. Specifically, we compare morphometrics statistically, then use computational fluid dynamics (CFD) to characterize predicted airflow and pressure over digitally reconstructed models of the salamanders. While similar in body and tail lengths, A. vagrans are more dorsoventrally flattened with longer limbs and greater surface area of the foot relative to body size than the nonarboreal E. eschscholtzii. CFD results show dorsoventral pressure gradients differ between the two digitally reconstructed salamanders resulting in lift coefficients of approximately 0.02 and 0.00, and lift:drag ratios of approximately 0.40 and 0.00 for A. vagrans and E. eschscholtzii, respectively. We conclude that the morphology of A. vagrans is better suited for controlled descent than that of the closely related E. eschscholtzii and highlight the importance of subtle morphological features, such as dorsoventral flatness, foot size, and limb length, for aerial control. That our simulation reports align with real-world performance data underscores the benefits of CFD for studying the link between morphology and aerodynamics in other taxa.

Hospital Costs, Revenue, and Abuse Detection Associated With Occult Injury Screening.

OBJECTIVE: Performance of occult injury screening including skeletal surveys and neuroimaging is recommended to comprehensively evaluate suspected child physical abuse. Screening performance-associated hospital costs and net revenue for care of index abuse victims and siblings/household contacts are largely unknown. We aimed to describe 1) costs and net revenue associated with radiologic occult injury screening at an urban level 1 pediatric trauma center, 2) areas of perceived high resource intensity (time spent in abuse victim-related care), and 3) detection yield among children undergoing occult injury screening and physical assessment. METHODS: Using time-driven activity-based cost analysis, hospital, per physician, staff, and radiology costs associated with occult injury screening performance were mapped for 199 children <2 years old. Hospital costs and resource times were approximated and compared with net revenue for each healthcare encounter. Abstracted variables included index/sibling status, injury classification, and length of stay (LOS). RESULTS: Of 199 children with variable LOS (0-45 days), total hospital costs (facility, physician, staff, radiology) ranged $297.83 to $81,474; net revenue was positive. Total ED time per abuse case varied 32 to 1823 minutes; social work (SW) time ranged 44 to 720 minutes; prolonged ED/SW time represented resource-intense areas. Of siblings, 27% were diagnosed with unanticipated findings based on occult injury screening and examination. CONCLUSIONS: At a single center, occult injury screening was associated with cost variability, resource intensity, and enhanced victim identification when external examination findings or clinical symptoms were absent. While further study is needed, cost and resource concerns associated with screening may be offset by societal benefit and minimal hospital-based financial losses.

Virtual and augmented reality: New tools for visualizing, analyzing, and communicating complex morphology.

Virtual and augmented reality (VR/AR) are new technologies with the power to revolutionize the study of morphology. Modern imaging approaches such as computed tomography, laser scanning, and photogrammetry have opened up a new digital world, enabling researchers to share and analyze morphological data electronically and in great detail. Because this digital data exists on a computer screen, however, it can remain difficult to understand and unintuitive to interact with. VR/AR technologies bridge the analog-to-digital divide by presenting 3D data to users in a very similar way to how they would interact with actual anatomy, while also providing a more immersive experience and greater possibilities for exploration. This manuscript describes VR/AR hardware, software, and techniques, and is designed to give practicing morphologists and educators a primer on using these technologies in their research, pedagogy, and communication to a wide variety of audiences. We also include a series of case studies from the presentations and workshop given at the 2019 International Congress of Vertebrate Morphology, and suggest best practices for the use of VR/AR in comparative morphology.

Association of Previous Concussion with Hippocampal Volume and Symptoms in Collegiate-Aged Athletes.

There is concern that previous concussion and contact-sport exposure may have negative effects on brain structure and function. Accurately quantifying previous concussion is complicated by the fact that multiple definitions exist, with recent definitions allowing for diagnosis based on the presence of symptoms alone (Concussion in Sport Group criteria; CISG) rather than the presence of acute injury characteristics such as alterations in mental status (American Congress of Rehabilitation Medicine criteria; ACRM). The goals of the current work were to determine the effects of previous concussion and contact-sport exposure on gray matter structure and clinical measures in healthy, young-adult athletes and determine the extent to which these associations are influenced by diagnostic criteria used to retrospectively quantify concussions. One-hundred eight collegiate-aged athletes were enrolled; 106 athletes were included in final analyses (age, 21.37 ± 1.69; 33 female). Participants completed a clinical battery of self-report and neurocognitive measures and magnetic resonance imaging to quantify subcortical volumes and cortical thickness. Semistructured interviews were conducted to measure exposure to contact sports and the number of previous concussions based on CISG and ACRM criteria. There was a significant association of concussion-related and psychological symptoms with previous concussions based on ACRM (ps < 0.05), but not CISG, criteria. Hippocampal volume was inversely associated with the number of previous concussions for both criteria (ps < 0.05). Findings provide evidence that previous concussions are associated with smaller hippocampal volumes and greater subjective clinical symptoms in otherwise healthy athletes and highlight the importance of diagnostic criteria used to quantify previous concussion.

Predictors of early versus late mortality in pelvic trauma patients.

BACKGROUND: Risks of predicting time-related in-hospital mortality varies in pelvic trauma patients. We aim to identify potential independent risks predictive of time-related (early versus late) mortality among pelvic trauma patients. METHODS: Local trauma registry data from 2004 through 2013 were reviewed. Mortality causes and timing of death were investigated. Multivariate logistic regression identified independent risks predictive of early versus late mortality in pelvic trauma patients while adjusting for patient demographics (age, sex, race), clinical variables (initial vital signs, mental status, injury severity, associated injuries, comorbidities), and hospital outcomes (surgical interventions, crystalloid resuscitations, blood transfusions). RESULTS: We retrospectively collected data on 1566 pelvic trauma patients with a mortality rate of 9.96% (156/1566). Approximately 74% of patients died from massive hemorrhage within the first 24 h of hospitalization (early mortality). Revised trauma score (RTS), injury severity score (ISS), initial hemoglobin, direct transfer to operating room, and blood transfusion administration in the Emergency Department were considered independent risk factors predictive of early mortality. Age, ISS, and Glasgow Coma Scale (GCS) were deemed risk factors predictive of death after 24 h (late mortality). DISCUSSION: Given the fact of a substantial number of patients died within the first 24 h of hospital arrival, it is reasonable to consider the first 24 h of hospitalization as the appropriate window within which early mortality may be expected to occur in pelvic trauma patients. The risk factors associated with massive hemorrhage were strong predictors of early mortality, whereas late mortality predictors were more closely linked with comorbidities or in-hospital complications. CONCLUSIONS: While risk factors predictive of early versus late mortality vary, ISS seems to predict both early and late mortality accurately in pelvic trauma patients.

Benefits of Initial Limited Crystalloid Resuscitation in Severely Injured Trauma Patients at Emergency Department.

BACKGROUND: Whether initial limited crystalloid resuscitation (LCR) benefits to all severely injured trauma patients receiving blood transfusions at emergency department (ED) is uncertain. We aimed to determine the role of LCR and its associations with packed red blood cell (PRBC) transfusion during initial resuscitation. METHODS: Trauma patients receiving blood transfusions were reviewed from 2004 to 2013. Patients with LCR (L group, defined as < 2,000 mL) and excessive crystalloid resuscitation (E group, defined as ≥ 2,000 mL) were compared separately in terms of basic demographic, clinical variables, and hospital outcomes. Logistic regression, R-square (R(2)), and Spearman rho correlation were used for analysis. RESULTS: A total of 633 patients were included. The mortality was 51% in L group and 45% in E group (P = 0.11). No statistically significant difference was found in terms of basic demographics, vital signs upon arrival at ED, or injury severity between the groups. The volume of blood transfused strongly correlated with the volume of crystalloid infused in E group (R(2) = 0.955). Crystalloid to PRBC (C/PRBC) ratio was 0.8 in L group and 1.3 in E group (P < 0.01). The correlations between C/PRBC and ED versus ICU versus hospital length of stay (LOS) via Spearman rho were 0.25, 0.22, and 0.22, respectively. CONCLUSIONS: Similar outcomes were observed in trauma patients receiving blood transfusions regardless of the crystalloid infusion volume. More crystalloid infusions were associated with more blood transfusions. The C/PRBC did not demonstrate predictive value regarding mortality but might predict LOS in severely injured trauma patients.

Photochemical Reactivity of W(CO)(4)(phen): Evidence for Prompt One-Electron Transfer in Competition with Vibrational Relaxation.

Excitation into either the metal-to-ligand charge-transfer, MLCT, band or the ligand field, LF, band of W(CO)(4)(phen) promoted an electron transfer to paraquat, PQ(2+). This process was observed spectroscopically by the appearance of the characteristic bands of the well-known radical cation PQ(*)(+). Both nanosecond and picosecond flash photolysis were used to further examine the electron-transfer reaction. Excitation of W(CO)(4)(phen) in the presence of 10 mM PQ(2+) using a 355 nm, 30 ps pulse revealed the formation of PQ(*)(+) within the pulse. This suggests the rate of electron transfer is above diffusion control and that either there must be some preassociation between the reactants prior to excitation or the reaction is mediated by formation of a solvent radical (in a "hot" electron transfer(?)). A 355 nm, 10 ns pulse was also used to excite W(CO)(4)(phen) in the presence of 10 mM PQ(2+). Again, PQ(*)(+) was formed promptly and persisted for times on the order of microseconds. Subsequently, competition between back electron transfer (tau = 17 &mgr;s) and net reaction was observed. The possibility of electron transfer to "inert" halocarbons was also investigated. Picosecond and nanosecond flash photolysis of W(CO)(4)(phen) using both 355 and 532 nm excitation in a halogenated solvent, C(2)Cl(4), yielded a spectrum indicative of the prompt formation (<30 ps) of reduced C(2)Cl(4). Available estimates of potentials require this to arise from a hot (not vibrationally relaxed) electron transfer.