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Messenger RNA (mRNA) delivered in lipid nanoparticles (LNPs) rose to the forefront of vaccine candidates during the COVID-19 pandemic due in part to scalability, adaptability, and potency. Yet there remain critical areas for improvements of these vaccines in durability and breadth of humoral responses. In this work, we explore a modular strategy to target mRNA/LNPs to antigen presenting cells with an injectable polymer-nanoparticle (PNP) hydrogel depot technology which recruits key immune cells and forms an immunological niche in vivo. We characterize this niche on a single cell level and find it is highly tunable through incorporation of adjuvants like MPLAs and 3M-052. Delivering commercially available SARS-CoV-2 mRNA vaccines in PNP hydrogels improves the durability and quality of germinal center reactions, and the magnitude, breadth, and durability of humoral responses. The tunable immune niche formed within PNP hydrogels effectively skews immune responses based on encapsulated adjuvants, creating opportunities to precisely modulate mRNA/LNP vaccines for various indications from infectious diseases to cancers.

The arthropod cuticle offers strength, protection, and lightweight. Due to its limit in expandability, arthropods have to moult periodically to grow. While moulting is beneficial in terms of parasite or toxin control, growth and adaptation to environmental conditions, it costs energy and leaves the soft animal's body vulnerable to injuries and desiccation directly after ecdysis. To investigate the temporal change in sclerotization and pigmentation during and after ecdysis, we combined macrophotography, confocal laser scanning microscopy, scanning electron microscopy and histological sectioning. We analysed the tarsal and mandibular cuticle of the blue emperor dragonfly to compare the progress of tanning for structures that are functionally involved during emergence (tarsus/tarsal claws) with structures whose functionality is required much later (mandibles). Our results show that: (i) the tanning of the tarsal and mandibular cuticle increases during emergence; (ii) the tarsal cuticle tans faster than the mandibular cuticle; (iii) the mandibles tan faster on the aboral than on the oral side; and (iv) both the exo- and the endocuticle are tanned. The change in the cuticle composition of the tarsal and mandibular cuticle reflects the demand for higher mechanical stability of these body parts when holding on to the substrate during emergence and during first walking or hunting attempts., Competing Interests: We declare we have no competing interests., (© 2024 The Author(s).)

Magnetic proxy approaches proved to be efficient for potentially toxic elements (PTEs) pollution assessment when targeting forests or areas with a homogenous background where anthropogenic magnetic signals could be easily distinguished. Here, we present a multidisciplinary approach for magnetic susceptibility ([Formula: see text]) and HM assessment in a complex area in the Nile Delta, where geogenic input, land use, and various industries with different fly ash and surface water emissions interfere. Statistical analysis discriminates between the effects of lithologic elements and the concentrations of toxic anthropogenic elements. The studied elements are classified into lithogenic and anthropogenic-related (HMs, Au industry, and fertilizers industry) groups with maximum contamination levels of eight anthropogenic-related and highly toxic PTEs (Cu, Zn, Mo, Cd, Sb, Pb, Hg, and As) in the Akrasha industrial area (pollution load index = 15.84). Considering the whole data set, the numerical correlation of [Formula: see text] with most PTE concentrations and the pollution load index (PLI) is weak, while it is moderate to strong with lithogenic elements. However, a comparison of lithogenic elements and PTE concentrations along with x-values in two separate clusters supports the correspondence of lithology with elevated x-values in silt and clay-rich soil samples as well as HM concentration in industrial sandy soils. Correspondence between magnetic maps and chemistry data with land use reflects the potential of magnetic proxy methods for qualitative PTE pollution pre-delineation of the polluted spots, provided that lithological conditions are carefully considered., (© 2024. The Author(s).)

Background: Virtual reality (VR) is increasingly considered a valuable therapeutic tool for people with dementia. However, rigorous studies are still needed to evaluate its impact on behavioral and psychological symptoms of dementia (BPSDs) and quality of life (QoL) across care settings., Objective: The primary aim of this study was to evaluate the impact of VR therapy on managing BPSDs, falls, length of stay, and QoL in inpatients with dementia admitted to an acute care hospital. The secondary aim was to evaluate the intervention's feasibility in terms of acceptability, safety, and patient experience., Methods: A prospective, open-label, mixed methods, randomized controlled clinical trial was conducted between April 2019 and March 2020. A total of 69 participants (aged ≥65 years with a diagnosis of dementia and who did not meet the exclusion criteria) were randomly assigned to either the control (n=35, 51%) or VR (n=34, 49%) arm. Participants in the experimental (VR) arm were visited by a researcher and watched 360° VR films on a head-mounted display for up to 20 minutes every 1 to 3 days, whereas individuals in the control arm received standard of care. Instances of daily BPSDs and falls were collected from nurses' daily notes. QoL was measured through semistructured interviews and the Quality of Life in Late-Stage Dementia scale. Structured observations and semistructured interviews were used to measure treatment feasibility. The primary outcomes were analyzed at a 95% significance level based on the intention-to-treat method., Results: VR therapy had a statistically significant effect on reducing aggressiveness (ie, physical aggression and loud vociferation; P=.01). Substantial impact of VR therapy was not found for other BPSDs (eg, apathy), falls, length of stay, or QoL as measured using the Quality of Life in Late-Stage Dementia scale. The average VR therapy session lasted 6.8 (SD 6.6; range 0-20) minutes, and the intervention was overall an acceptable and enjoyable experience for participants. No adverse events occurred as a result of VR therapy., Conclusions: Immersive VR therapy appears to have an effect on aggressive behaviors in patients with dementia in acute care. Although the randomized controlled trial was stopped before reaching the intended sample size owing to COVID-19 restrictions, trends in the results are promising. We suggest conducting future trials with larger samples and, in some cases, more sensitive data collection instruments., Trial Registration: ClinicalTrials.gov NCT03941119; https://clinicaltrials.gov/study/NCT03941119., International Registered Report Identifier (irrid): RR2-10.2196/22406., (©Lora Appel, Eva Appel, Erika Kisonas, Samantha Lewis-Fung, Susanna Pardini, Jarred Rosenberg, Julian Appel, Christopher Smith. Originally published in the Journal of Medical Internet Research (https://www.jmir.org), 30.01.2024.)

Although iso-centric patient positioning is enormously important in computed tomography (CT), it is complicated in thoracoabdominal imaging by the varying dimensions of the body. Patient positioning can affect the appearance of the patient on the localiser. Positioned too close to the x-ray tube, a patient appears considerably more voluminous. The goal of this study is to assess the difference in radiation exposure of combined chest and abdomen CT scans between scans with prior 0°- and 180°-localisers in conjunction with patient positioning. In this IRB-approved retrospective study, patients who had two routine thoracoabdominal CT scans on the same CT scanner, one with a prior 0°- and one with a prior 180°-localiser, were included. To evaluate the radiation exposure of the thoracoabdominal CT examination regarding the tube position during the localiser, volumetric computed tomography dose index (CTDI vol ), size-specific dose estimate (SSDE), patient diameter and positioning within the iso-centre for three positions (heart, abdomen, femur level) were compared with regard to the tube position during the prior localiser. CT examinations of 114 patients were included. Despite similar patient weight and diameter between the two examinations, SSDE and CTDI vol was significantly larger (up to 73%) with 180°-localisers. Patient offset from the iso-centre ranged between -9 mm at the centre slice (abdomen level) to -43 mm at the most caudal slice at the pelvis (femur level), causing a significant magnification (p < 0.001) on 180°-localisers with a subsequent increase of the apparent attenuation. The results of this study emphasise the use of 0°-localisers in thoracoabdominal CTs, since 180°-localisers caused patient magnification with subsequent increase in radiation exposure. The advantage of 180°-localisers, namely reducing the dose in thyroid and breast, is eliminated if the dose of the CT scan increases significantly in the abdomen and pelvis., (Creative Commons Attribution license.)

Purpose: To assess whether it is possible to reliably detect patients with strong suspicion of COVID-19 despite initially negative quantitative polymerase-chain-reaction (qPCR) tests by means of computed tomography (CT)., Materials and Methods: 437 patients with suspected COVID-19 but initially negative qPCR and subsequent chest CT between March 13 and November 30, 2020 were included in this retrospective study. CT findings were compared to results of successive qPCR tests (minimum of 3 qPCR tests if CT suggested infection) to determine the sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of CT for diagnosing COVID-19., Results: COVID-19 was diagnosed correctly with a sensitivity of 100 % [95 % confidence interval (CI): 65-100] and a specificity of 88 % [95 % CI: 84-90]. A PPV of 12 % [95 % CI: 6-22] and an NPV of 100 % [95 % CI: 99-100] were determined., Conclusion: CT is able to detect COVID-19 before qPCR in initially negative patients in this special study setting. Similar CT findings in COVID-19 and other atypical pneumonias can lead to high numbers of false-positive patients, reducing the specificity of CT., Key Points: · Low-dose chest CT is able to diagnose COVID-19 in symptomatic patients even in cases of an initially negative quantitative PCR result and therefore is a fast support method to detect COVID-19, especially in early disease.. · Low-dose chest CT can reliably exclude COVID-19 in a pandemic setting.. · CT does not always ensure a reliable differentiation from other viral diseases.., Citation Format: · Valentin B, Steuwe A, Wienemann T, et al. CT Findings in Patients with COVID-19-Compatible Symptoms but Initially Negative qPCR Test. Fortschr Röntgenstr 2022; 194: 1110 - 1118., Competing Interests: The authors declare that they have no conflict of interest., (Thieme. All rights reserved.)

Background: Patients with interatrial shunts (patient foramen ovale/atrial septal defect) are potentially at increased risk for paradoxical air embolism following computed tomography (CT) scans with intravenous (IV) contrast media injection. IV in-line filters aim to prevent such embolisms but are not compatible with power injection required for diagnostic CT., Purpose: The purpose of this study was to determine whether the incidence of paradoxical embolism to the heart and brain in patients with an interatrial shunt is higher compared with controls within 48 hours following injection of IV contrast media without IV in-line filter., Methods: This is a retrospective cohort study conducted at a large tertiary academic center, which included a total of 2929 consecutive patients who underwent 8983 CT scans with IV contrast media injection between July 1, 2000 and April 30, 2018. Diagnosis of an interatrial shunt was confirmed by transthoracic or transesophageal echocardiography. Incidence and risk of cardiac embolic events (new troponin elevation, >0.1 ng/mL) and neurological embolic events (new diagnosis of stroke/transient ischemic attacks) were evaluated., Results: Among the 2929 patients analyzed (mean±SD age, 61±14 y), 475/2929 (16.2%) patients had an interatrial shunt. After applying the exclusion criteria, new elevated troponin was found in 8/329 (2.4%; 95% confidence interval [CI]: 1.1-4.7) patients with an interatrial shunt compared with 25/1687 (1.5%; 95% CI: 0.9-2.2) patients without an interatrial shunt. New diagnosis of stroke occurred in 2/169 (1%; 95% CI: 0.3-4.2) of patients with an interatrial shunt compared with 7/870 (0.8%; 95% CI: 0.4-1.7) without interatrial shunt., Conclusion: Among patients with echocardiographic evidence of an interatrial shunt, IV CT contrast administration without an in-line filter does not increase the incidence of cardiac or neurological events., Competing Interests: The authors declare no conflict of interest., (Copyright © 2022 Wolters Kluwer Health, Inc. All rights reserved.)

Purpose: Classifications were created to facilitate radiological evaluation of the novel coronavirus disease 2019 (COVID-19) on computed tomography (CT) images. The categorical CT assessment scheme (CO-RADS) categorizes lung parenchymal changes according to their likelihood of being caused by SARS-CoV-2 infection. This study investigates the diagnostic accuracy of diagnosing COVID-19 with CO-RADS compared to the Thoracic Imaging Section of the German Radiological Society (DRG) classification and Radiological Society of North America (RSNA) classification in an anonymized patient cohort. To mimic advanced disease stages, follow-up examinations were included as well., Method: This study includes all patients undergoing chest CT in the case of a suspected SARS-CoV-2 infection or an already confirmed infection between March 13 and November 30, 2020. During the study period, two regional lockdowns occurred due to high incidence values, increasing the pre-test probability of COVID-19. Anonymized CT images were reviewed retrospectively and in consensus by two radiologists applying CO-RADS, DRG, and RSNA classification. Afterwards, CT findings were compared to results of sequential real-time reverse transcriptase polymerase chain reaction (qPCR) test performed during hospitalization to determine statistical analysis for diagnosing COVID-19., Results: 536 CT examinations were included. CO-RADS, DRG and RSNA achieved an NPV of 96 %/94 %/95 % (CO-RADS/DRG/RSNA), PPV of 83 %/80 %/88 %, sensitivity of 86 %/76 %/80 %, and specificity of 96 %/95 %/97 %. The disease prevalence was 20 %., Conclusion: All applied classifications can reliably exclude a SARS-CoV-2 infection even in an anonymous setting. Nevertheless, pre-test probability was high in our study setting and has a great influence on the classifications. Therefore, the applicability of the individual classifications will become apparent in the future with lower prevalence and incidence of COVID-19., Key Points: · CO-RADS, DRG, and RSNA classifications help to reliably detect infected patients in an anonymized setting. · Pre-test probability has a great influence on the individual classifications. · Difficulties in an anonymized study setting are severe pulmonary changes and residuals.., Citation Format: · Valentin B, Steuwe A, Wienemann T et al. Applicability of CO-RADS in an Anonymized Cohort Including Early and Advanced Stages of COVID-19 in Comparison to the Recommendations of the German Radiological Society and Radiological Society of North America. Fortschr Röntgenstr 2022; 194: 862 - 872., Competing Interests: The authors declare that they have no conflict of interest., (Thieme. All rights reserved.)

Purpose: To evaluate diagnostic accuracy and clinical outcomes of patients with porcelain gallbladder (GB) diagnosed on CT., Materials and Methods: In this IRB-approved, HIPAA-compliant study, consecutive patients with porcelain gallbladder reported on CT between December 1, 2000 and August 31, 2017 in a tertiary academic center were included. Two radiologists independently reviewed CT images and confirmed presence of porcelain gallbladder. Discrepant cases were reviewed by a third reader with 15 years of experience in abdominal imaging. Porcelain gallbladder diagnosis was confirmed by surgery/pathology or follow-up imaging., Results: Porcelain gallbladder was reported in 133 CT studies. Radiologist review and pathology results confirmed porcelain gallbladder in 90/133 (68%) patients (age 71.6 ± 13.8 years, 57% female). One third (42/133; 32%) of CT reports were false positive; 1/133 (1%) remained indeterminate. Frequent pitfalls included: stones filling the whole gallbladder lumen in 39/43 (91%), sludge in 3/43 (7%) and mucosal enhancement in 2/43 (5%). In 5/90 (6%) patients, concurrent gallbladder cancer was noted on the initial CT scan. No patient developed subsequent gallbladder cancer during 6.6 ± 4.6 years of follow-up. One third (30/90, 33%) of patients with porcelain gallbladder have deceased during the follow-up period, all from unrelated causes., Conclusion: At the time of presentation with porcelain gallbladder, 6% of patients had concurrent gallbladder cancer. No patient with porcelain gallbladder alone diagnosed on CT developed gallbladder cancer during a follow-up of 6.6 ± 4.6 years. Porcelain gallbladder is overcalled on CT, with frequent pitfalls including gallstones filling the whole gallbladder lumen, sludge, and wall enhancement., (Copyright © 2020 The Association of University Radiologists. Published by Elsevier Inc. All rights reserved.)

Objective: To assess accuracy of dual-energy computed tomography (DECT) to differentiate uric acid from calcium urinary stones in dual-energy split filter vs sequential-spiral vs dual-source acquisition., Methods: Thirty-four urinary stones (volume 89.0 ± 77.4 mm³; 17 calcium stones, 17 uric acid stones) were scanned in a water-filled phantom using a split-filter equipped CT scanner (SOMATOM Definition Edge, Siemens Healthineers, Forchheim, Germany) in split-filter mode at 120 kVp and sequential-spiral mode at 80 and 140 kVp. Additional DE scans were acquired at 80 and 140 kVp (tin filter) with a dual-source CT scanner (SOMATOM Definition FLASH, Siemens Healthineers). Scans were performed with a CTDIvol of 7.3 mGy in all protocols. Urinary stone categorization was based on dual energy ratio (DER) using an automated 3D segmentation. As reference standard, infrared spectroscopy was used to determine urinary stone composition., Results: All three DECT techniques significantly differentiated between uric acid and calcium stones by attenuation values and DERs ( p < 0.001 for all). Split-filter DECT provided higher DERs for uric acid stones, when compared with dual-source and sequential-spiral DECT, and lower DERs for calcified stones when compared with dual-source DECT ( p < 0.001 for both), leading to a decreased accuracy for material differentiation., Conclusion: Split-filter DECT, sequential-spiral DECT and dual-source DECT all allow for the acquisition of DER to classify urinary stones., Advances in Knowledge: Split-filter DECT enables the differentiation between uric acid and calcium stones despite decreased spectral separation when compared with dual-source and dual-spiral DECT.

Introduction: Sciatic hernias are the rarest form of pelvic floor hernias as well as an uncommon cause of sciatica. A high index of suspicion is required to make the diagnosis due to its variable clinical presentation. This is the first case describing bilateral intestinal sciatic hernia, diagnosis, and robotic surgical repair., Presentation of Case: A 77-year-old female with history of chronic back pain and diverticulitis presented with three weeks of abdominal pain, radiating down her legs bilaterally. Computed tomography (CT) revealed bilateral sciatic notch hernias without evidence of bowel obstruction. Magnetic resonance imaging (MRI) confirmed compression of the sciatic nerves within the sciatic notch bilaterally. She underwent robotic bilateral retroperitoneal sciatic notch hernia repair successfully., Discussion: There are several independent causes of abdominal pain and bilateral radiating leg pain. Sciatic hernias are an unusual cause of both. Aside from bowel, the hernia can involve other structures, such as the bladder, ureters, or ovaries, potentially creating drastically different clinical pictures. Laparoscopic or robotic repair have been proven superior to open surgery in the literature., Conclusion: This case demonstrates that bilateral sciatic hernias can present as uncomplicated sciatica in an elderly patient, but the addition of seemingly unrelated abdominal pain should warrant further investigation. Minimally invasive robotic repair can successfully treat sciatic hernias., (Copyright © 2021. Published by Elsevier Ltd.)

Objective: To determine safety of shortened observation time without follow-up chest x-ray (CXR) after CT-guided transthoracic procedures (lung biopsy or fiducial placement) in patients without immediate postprocedural pneumothorax (PTX)., Methods: Consecutive patients that underwent CT-guided procedures between January 5, 2015, and June 19, 2017, were included in this retrospective institutional review board-approved HIPAA-compliant study. Data regarding postprocedural course, complications, and clinical follow-up of the patients were obtained through a review of electronic medical records. Descriptive statistics were used., Results: There were 441 procedures for 409 patients performed; 82 procedures were excluded because of predefined criteria. In 312 of 336 asymptomatic procedures (92.9%), asymptomatic patients did not undergo CXR after procedure, with 7 of 312 of these patients (2.2%) diagnosed with delayed PTX 2 to 10 days after the procedure. In 24 of 336 procedures (7.1%), asymptomatic patients underwent CXR within 4 hours with no PTX detected, and despite that 1 of 24 of these patients (4.2%) presented with delayed PTX 7 days after procedure. When no immediate postprocedural PTX was present, rate of observation PTX and delayed PTX was 1 of 359 (0.3%) and 8 of 359 (2.2%), respectively. Average duration of monitoring for outpatients (n = 295) was 2.0 hours with median of 1.8 hours. In 23 of 359 (6.4%) procedures, the patient became symptomatic during postprocedural observation with 1 of 23 (4%) developing PTX., Conclusions: Obtaining routine postprocedural CXRs in asymptomatic patients without immediate postprocedural PTX after CT-guided transthoracic procedures is likely not necessary given the low likelihood of PTX., (Copyright © 2021 American College of Radiology. Published by Elsevier Inc. All rights reserved.)

Background: Motion correction is mandatory for the functional Fourier decomposition magnetic resonance imaging (FD-MRI) of the lungs. Therefore, it is important to evaluate the quality of various image-registration algorithms for pulmonary FD-MRI and to determine their impact on FD-MRI outcome., Purpose: To evaluate different image-registration algorithms for FD-MRI in functional lung imaging., Material and Methods: Fifteen healthy volunteers were examined in a 1.5-T whole-body MR scanner (Magnetom Avanto, Siemens AG) with a non-contrast enhanced 2D TrueFISP pulse sequence in coronal view and free-breathing (acquisition time 45 s, 250 images). Three image-registration algorithms were used to compensate the spatial variation of the lungs (fMRLung 3.0, ANTs, and Elastix). Quality control for image registration was performed by edge detection (ED), quotient image criterion (QI), and dice similarity coefficient (DSC). Ventilation, perfusion, and a ventilation/perfusion quotient (V/Q) were calculated using the three registered datasets., Results: Average computing times for the three image-registration algorithms were 1.0 ± 1.6 min, 38.0 ± 13.5 min, and 354 ± 78 min for fMRLung, ANTs, and Elastix, respectively. No significant difference in the quality of motion correction provided by different image-registration algorithms occurred. Significant differences were observed between fMRLung- and Elastix-based perfusion values ​​of the left lung as well as fMRLung- and ANTs-based V/Q quotient of the right and the entire lung ( P  < 0.05). Other ventilation and perfusion values were not significantly different., Conclusion: The mandatory motion correction for functional FD-MRI of the lung can be achieved through different image-registration algorithms with consistent quality. However, a significantly difference in computing time between the image-registration algorithms still requires an optimization.

Background: As virtual reality (VR) technologies become increasingly accessible and affordable, clinicians are eager to try VR therapy as a novel means to manage behavioral and psychological symptoms of dementia, which are exacerbated during acute care hospitalization, with the goal of reducing the use of antipsychotics, sedatives, and physical restraints associated with negative adverse effects, increased length of stay, and caregiver burden. To date, no evaluations of immersive VR therapy have been reported for patients with dementia in acute care hospitals., Objective: This study aimed to determine the feasibility (acceptance, comfort, and safety) of using immersive VR therapy for people living with dementia (mild, moderate, and advanced) during acute care hospitalization and explore its potential to manage behavioral and psychological symptoms of dementia., Methods: A prospective, longitudinal pilot study was conducted at a community teaching hospital in Toronto. The study was nonrandomized and unblinded. A total of 10 patients aged >65 years (mean 86.5, SD 5.7) diagnosed with dementia participated in one or more research coordinator-facilitated sessions of viewing immersive 360° VR footage of nature scenes displayed on a Samsung Gear VR head-mounted display. This mixed-methods study included review of patient charts, standardized observations during the intervention, and pre- and postintervention semistructured interviews about the VR experience., Results: All recruited participants (N=10) completed the study. Of the 10 participants, 7 (70%) displayed enjoyment or relaxation during the VR session, which averaged 6 minutes per view, and 1 (10%) experienced dizziness. No interference between the VR equipment and hearing aids or medical devices was reported., Conclusions: It is feasible to expose older people with dementia of various degrees admitted to an acute care hospital to immersive VR therapy. VR therapy was found to be acceptable to and comfortable by most participants. This pilot study provides the basis for conducting the first randomized controlled trial to evaluate the impact of VR therapy on managing behavioral and psychological symptoms of dementia in acute care hospitals., (©Lora Appel, Erika Kisonas, Eva Appel, Jennifer Klein, Deanna Bartlett, Jarred Rosenberg, Christopher NC Smith. Originally published in JMIR Formative Research (http://formative.jmir.org), 03.02.2021.)

Hymenoptera are characterised by the presence of one forewing pair and one hindwing pair. The two wings of each body side are coupled to each other during flight making the morphologically four-winged insects functionally two-winged. This coupling is formed by a row of hook-like structures, called hamuli, that are located at the leading edge of the hindwing and interlock with a thickened and recurved margin present at the trailing edge of the forewing. In this study, autofluorescence analyses performed with confocal laser scanning microscopy revealed differences in the exoskeleton material composition of the interlocking structures. While the wing veins and the recurved margin are strongly sclerotised and chitinous, the wing membranes mainly contain the elastomeric protein resilin. The hamuli are composed of sclerotised chitinous material, and each hamulus base is surrounded by and embedded in material that features large proportions of resilin and is located in strongly sclerotised socket-like wing vein structures. This exoskeleton organisation likely allows movements of the hamuli and, in combination with the exoskeleton material gradients visualized in the other interlocking structures, is assumed to guarantee an effective wing coupling and to simultaneously decrease the risk of wear and damage under mechanical loads occurring in flight, coupling and decoupling situations., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

Objectives: The aims of the study were to systematically analyze causes for radiation dose outliers in emergency department noncontrast head computed tomographies (CTs), to develop and implement standardized system solutions, and audit program success for an extended period of time., Methods: This study was performed in a large, tertiary academic center between January 2015 and September 2017. Four phases of radiation dose data collection with and without prior interventions were performed. Outliers from 5 categories were evaluated for appropriateness in consensus by 2 radiologists and a senior CT technologist., Results: A total of 275 ± 15 CTs per period were included. Fifty-seven inappropriate scanning parameters were found in 24 (9%) of 254 CTs during the first analysis, 27 in 21 (7%) of 290 CTs during the second, 11 in 10 (4%) of 276 during the third assessment (P = 0.006). After a year without additional intervention, the number remained stable (14 in 11/281 CTs, 4%)., Conclusions: Combining a dose reporting system, individual case analysis, staff education, and implementation of systemic solutions lead to sustained radiation exposure improvement., Competing Interests: The authors declare no conflict of interest., (Copyright © 2020 Wolters Kluwer Health, Inc. All rights reserved.)

Ischemic heart disease is the most common type of heart disease, responsible for roughly 10 million deaths worldwide annually. While standard clinical interventions have resulted in improved patient outcomes, access to small diameter vessels required for cardiovascular interventions, and long-term patient mortality rates associated with eventual heart failure, remain critical challenges. In this current opinion piece we discuss novel methodologies for the advancement of vascular grafts, cardiac patches, and injectable drug delivery depot technologies as they relate to treatment of ischemic heart disease, including bilayered conduits, acellular bioactive extracellular matrix (ECM) scaffolds, and protease-responsive hydrogel delivery platforms. We address the motivation for innovation and current limitations in the field of engineered biomaterials for myocardial ischemia therapeutics and interventions., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

Objectives: To evaluate the impact of patient positioning during CT-guided lung biopsy on patients' outcomes., Methods: In this retrospective, IRB-approved, HIPAA-compliant study, consecutive CT-guided lung biopsies performed on 5/1/2015-12/26/2017 were included. Correlation between incidence of pneumothorax, chest tube placement, pulmonary bleeding with patient, and procedure characteristics was evaluated. Lesion-trachea-table angle (LTTA) was defined as an angle between the lesion, trachea, and horizontal line parallel to the table. Lesion above trachea has a positive LTTA. Univariate and multivariate logistic regression analysis was performed., Results: A total of 423 biopsies in 409 patients (68 ± 11 years, 231/409, 56% female) were included in the study. Pneumothorax occurred in 83/423 (20%) biopsies with chest tube placed in 11/423 (3%) biopsies. Perilesional bleeding occurred in 194/423 (46%) biopsies and hemoptysis in 20/423 (5%) biopsies. Univariate analysis showed an association of pneumothorax with smaller lesions (p = 0.05), positive LTTA (p = 0.002), and lesions not attached to pleura (p = 0.026) with multivariate analysis showing lesion size and LTTA to be independent risk factors. Univariate analysis showed an association of increased pulmonary bleeding with smaller lesions (p < 0.001), no attachment to the pleura (p < 0.001), needle throw < 16 mm (p = 0.05), and a longer needle path (p < 0.001). Multivariate analysis showed lesion size, a longer needle path, and lesions not attached to the pleura to be independently associated with perilesional bleeding. Risk factors for hemoptysis were longer needle path (p = 0.002), no attachment to the pleura (p = 0.03), and female sex (p = 0.04)., Conclusions: Interventional radiologists can reduce the pneumothorax risk during the CT-guided biopsy by positioning the biopsy site below the trachea., Key Points: • Positioning patient with lesion to be below the trachea for the CT-guided lung biopsy results in lower rate of pneumothorax, as compared with the lesion above the trachea. • Positioning patient with lesion to be below the trachea for the CT-guided lung biopsy does not affect rate of procedure-associated pulmonary hemorrhage or hemoptysis.

Background: Behavioural and psychological symptoms of dementia (BPSD) are difficult to manage, particularly in acute care settings. As virtual reality (VR) technology becomes increasingly accessible and affordable, there is growing interest among clinicians to evaluate VR therapy in hospitalized patients, as an alternative to administering antipsychotics/sedatives or using physical restraints associated with negative side effects., Objectives: Validate and refine the proposed research protocol for a randomized controlled trial (RCT) that evaluates the impact of VR therapy on managing BPSD in acute care hospitals. Special attention was given to ascertain the processes of introducing non-pharmacological interventions in acute care hospitals., Methods: Ten patients 65 years or older (mean = 87) previously diagnosed with dementia, admitted to an acute care hospital, were recruited over 3-month period into a prospective longitudinal pilot study. The intervention consisted of viewing 20-min of immersive 360° VR using a head-mounted display. Baseline and outcomes data were collected from the hospital electronic medical records, pre/post mood-state questionnaires, Neuropsychiatric Inventory (NPI) score, and standardized qualitative observations. Comprehensive process data and workflow were documented, including timestamps for each study task and detailed notes on personnel requirements and challenges encountered., Results: Of 516 patients admitted during the study, 67 met the inclusion/exclusion criteria. In total, 234 calls were initiated to substitute decision makers (SDM) of the 67 patients for the consenting process. Nearly half (45.6%) of SDMs declined participation, and 40% could not be reached in time before patients being discharged, resulting in 57 eligible patients not being enrolled. Ten consented participants were enrolled and completed the study. The initial VR session averaged 53.6 min, largely due to the administration of NPI (mean = 19.5 min). Only four participants were able to respond reliably to questions. Seven participants opted for additional VR therapy sessions; of those providing feedback regarding the VR content, they wanted more varied scenery (animals, fields of flowers, holiday themes). Few sessions (4/18) encountered technical difficulties., Conclusion: The pilot was instrumental in identifying issues and providing recommendations for the RCT. Screening, inclusion criteria, consenting, data collection, and interaction with SDMs and hospital staff were all processes requiring changes and optimizations. Overall, patients with dementia appear to tolerate immersive VR, and with suggested protocol alterations, it is feasible to evaluate this non-pharmacological intervention in acute care hospitals.

Objectives: The detection of Coronavirus Disease 2019 (COVID-19) by reverse transcription polymerase chain reaction (RT-PCR) has varying sensitivity. Computed tomography (CT) of the chest can verify infection in patients with clinical symptoms and a negative test result, accelerating treatment and actions to prevent further contagion. However, CT employs ionising radiation. The purpose of this study was to evaluate protocol settings, associated radiation exposure, image quality and diagnostic performance of a low-dose CT protocol in a university hospital setting., Materials and Methods: Chest CT examinations were performed on a single scanner (Somatom Definition Edge, Siemens Healthineers, Germany) in 105 symptomatic patients (60 male, 45 female). Images were evaluated with regard to protocol parameters, image quality, radiation exposure and diagnostic accuracy. Serial RT-PCR served as the standard of reference. Based on this reference standard sensitivity, specificity, positive and negative predictive values of CT with 95% confidence interval were calculated., Results: The mean effective dose was 1.3 ± 0.4 mSv (0.7-2.9 mSv) for the patient cohort (mean age 66.6 ± 16.7 years (19-94 years), mean body mass index (BMI) 26.6 ± 5.3 kg m -2 (16-46 kg/m 2 )). A sensitivity of 100 [95% CI: 82-100]%, a specificity of 78 [95% CI: 68-86]%, a positive predictive value of 50 [95% CI: 33-67]% and a negative predictive value of 100 [95% CI: 95-100]% were obtained. No COVID-19 diagnoses were missed by CT. Image noise did not strongly correlate with BMI or patient diameter and was rated as average., Conclusions: We presented a robust imaging procedure with a chest CT protocol for confident diagnosis of COVID-19. Even for an overweight patient cohort, an associated radiation exposure of only 1.3 ± 0.4 mSv was achieved with sufficient diagnostic quality to exclude COVID-19.

Objective: To assess impact of single-energy metal artifact reduction (SEMAR) algorithm utilizing retrospective adaptive thresholding in reducing metal artifacts in the abdomen and pelvis., Methods: In this prospective institutional review board-approved, Health Insurance Portability and Accountability Act-compliant study, 90 patients with various metals (n = 97) on computed tomography of abdomen and pelvis (Canon Medical, Aquilion ONE and PRIME) scanned 07/2017-09/2018 with SEMAR retrospectively applied were included. Density was measured in the near and far field to the metals. Density standard deviation (SD), representing artifact severity, was compared with and without SEMAR applied. Two trained human observers independently evaluated severity of artifacts on a five-point scale (0, no artifact; 5, severe artifact)., Results: The SEMAR significantly decreased artifact severity in the near field of high-density metal implants (SD of 204 ± 101HU without vs. 66 ± 40HU with SEMAR, P < 0.001). In the far field, the artifact severity was similar (40 ± 31HU without vs. 36 ± 27HU with SEMAR, P = 0.41). Artifact severity was decreased adjacent to low-density metal in the near field (SD of 86 ± 56HU without vs 49 ± 30HU with SEMAR, P < 0.001). In the far field to the low-density metals artifact severity was similar (33 ± 29HU without vs. 31 ± 27HU with SEMAR, P = 0.79). Subjectively, artifacts severity decreased for high-density metals in near field by 1.3 ± 1.0, and in far field by 0.7 ± 0.7 and for low-density metals in the near field by 0.7 ± 1.0, far field 0.4 ± 0.5, all P < 0.05., Conclusions: The SEMAR retrospective algorithm with adaptive thresholding subjectively and objectively reduced near-field artifacts generated by high- and low-density metals.

Previous studies indicated serious soil arsenic (As) pollution of large spatial extent related to tungsten mining. We performed systematic analyses of magnetic parameters and As contents of a slag covered soil profile close to the abandoned tungsten mine in southern China, in order to discuss the feasibility of using sensitive, non-destructive, and cost-effective magnetic methods for monitoring the soil arsenic content in such arsenic pollution areas. The results indicate that arsenic sulfide entered from slags into the underlying soil and changed to iron arsenate and moveable arsenic ion. The arsenic ions were transported from the upper to the lower part of the soil profile, leading to more serious arsenic pollution at lower levels of the section. Pedogenesis and oxidation of the entered iron and arsenic sulfide resulted in coexistence of magnetite/maghemite and hematite, with different contributions at depths of 125-195 cm, 60-125 cm, and 0-60 cm. The arsenic content is significant positively correlated with the hematite concentration given by the magnetic parameter HIRM and negatively correlated with the S -300 ratio that measures the relative contributions of magnetite(+maghemite) and hematite. The S -300 ratio is effective for semi-quantification of soil arsenic content, and may be also used for soil arsenic pollution assessment and monitoring in similar settings of tungsten mining.

Background: Older adults living in long term care, rehabilitation hospitals, and seniors' residences often experience reduced mobility, sometimes resulting in confinement indoors and isolation, which can introduce or aggravate symptoms of depression, anxiety, loneliness, and apathy. As Virtual Reality (VR) technologies become increasingly accessible and affordable, there is a unique opportunity to enable older adults to escape their restricted physical realities and be transported to both stimulating and calming places which may improve their general well-being. To date no robust evaluations of the use of immersive VR therapy [experienced through a head-mounted-display (HMD)] for older adults within these settings have been reported. VR-therapy may prove to be a safe, inexpensive, non-pharmacological means of managing depressive symptoms and providing engagement and enjoyment to this rapidly growing demographic. Objectives: Establish whether it is feasible to use immersive VR technology as therapy for older adults who have reduced sensory, mobility and/or impaired cognition. This includes evaluation of tolerability, comfort, and ease of use of the HMD, and of the potential for immersive VR to provide enjoyment/relaxation and reduce anxiety and depressive symptoms. Methods: Sixty-six older adults (mean age 80.5, SD = 10.5) with varying cognitive abilities (normal = 28, mild impairment = 17, moderate impairment = 12, severe impairment = 3, unknown cognitive score = 6), and/or physical impairments, entered a multi-site non-randomized interventional study in Toronto, Canada. Participants experienced 3 to 20 min of 360°-video footage of nature scenes displayed on Samsung GearVR HMD. Data was collected through pre/post-intervention surveys, standardized observations during intervention, and post-intervention semi-structured interviews addressing the VR experience. Results: All participants completed the study with no negative side-effects reported (e.g., No dizziness, disorientation, interference with hearing aids); the average time spent in VR was 8 min and 76% of participants viewed the entire experience at least once. Participants tolerated the HMD very well; most had positive feedback, feeling more relaxed and adventurous; 76% wanted to try VR again. Better image quality and increased narrative video content were suggested to improve the experience. Conclusion: It is feasible and safe to expose older adults with various levels of cognitive and physical impairments to immersive VR within these settings. Further research should evaluate the potential benefits of VR in different settings (e.g., home/community based) and explore better customization/optimization of the VR content and equipment for the targeted populations., (Copyright © 2020 Appel, Appel, Bogler, Wiseman, Cohen, Ein, Abrams and Campos.)

Shell matrix proteins (SMPs) are occluded within molluscan shells and are fundamental to the biological control over mineralization. While many studies have been performed on adult SMPs, those of larval stages remain largely undescribed. Therefore, this study aimed to characterize the larval shell proteome of the blue mussel for the first time and to compare it to adult mussel shell proteomes. Following development of a method for cleaning larval shells of tissue contaminants, 49 SMPs were identified using shotgun proteomics. Twenty-one proteins were independently identified in all samples indicating that they form a subset of the core larval shell proteome. These included: the blue mussel shell protein, a peroxidase domain-containing sequence, a laminin G domain-containing sequence, a ZIP domain-containing sequence and a ferric-chelate reductase 1-like sequence. Additional SMP domains identified were: fibronectin type III, BPTI/Kunitz, chitin-binding type 3, thyroglobulin and EF-hand. While key predictable molluscan shell matrix functions are identified, 67% of sequences remain unknown or uncharacterized, indicating that this shell proteome is unique to mussel larvae. Specifically, comparison with adult mytilids reveals that nine domains are exclusive to the larval shell proteome and only four domains are conserved among species and developmental stages. Thus, strong species-specific and ontogenetic variation exists in shell proteome composition., (Copyright © 2019 Elsevier Inc. All rights reserved.)

Rationale and Objectives: To generate institutional size-specific diagnostic reference levels (DRLs) for computed tomography angiography (CTA) examinations and assess the potential for dose optimization compared to size-independent DRLs., Materials and Methods: CTA examinations of the aorta, the pulmonary arteries and of the pelvis/lower extremity performed between January 2016 and January 2017 were included in our retrospective study. Water equivalent diameter (Dw) was automatically calculated for each patient. The relationship between Dw and computed tomography dose index (CTDI vol ) was analyzed and the 75th percentile was chosen as the upper limit for institutional DRLs. Size-specific institutional DRLs were compared to national size-independent DRLs from Germany and the UK., Results: A total of 1344 examinations were included in our study (n = 733 aortic CTA, n = 406 pulmonary CTA, n = 205 pelvic/lower extremity CTA). Mean Dw was 26 ± 9 cm and mean CTDI vol was 7.0 ± 4.6 mGy. For all CTA protocols, there was a linear progression of CTDI vol with increasing Dw with an R² = 0.95 in aortic CTA, R² = 0.94 in pulmonary CTA and R² = 0.93 in pelvic/lower extremity CTA. Median CTDI vol increased by 0.57 mGy per additional cm Dw in aortic CTA, by 1.1 mGy in pulmonary CTA and by 0.31 mGy in pelvic/lower extremity CTA. Institutional DRLs were lower than national DRLs for average size patients (aortic CTA: Dw 28.2 cm, CTDI vol 7.6 mGy; pulmonary CTA, Dw 27.9 cm, CTDI vol 11.8 mGy; pelvic/lower extremity CTA, Dw 20.0 cm, CTDI vol 6.4 mGy). More dose outliers in small patients were detected with size-specific DRLs compared to national size-independent DRLs (56.4% vs 16.2%)., Conclusion: We implemented institutional size-specific DRLs for CTA examinations which enabled a more precise analysis compared to national sizeindependent DRLs., (Copyright © 2019 The Association of University Radiologists. Published by Elsevier Inc. All rights reserved.)

Purpose: To evaluate the technical and clinical success rates and safety of bilateral gelfoam uterine artery embolization (UAE) for symptomatic acquired uterine arteriovenous shunting due to prior obstetric or gynecologic event., Materials and Methods: This was a retrospective study of consecutive patients of reproductive age who presented with abnormal uterine bleeding after recent gynecologic procedures or obstetric events between January 2013 and February 2018. Bilateral UAE was performed in all patients using gelfoam slurry. Technical success was defined as angiographic resolution of arteriovenous shunting. Clinical success was defined as cessation of symptomatic bleeding, resolution on follow-up imaging, or minimal estimated blood loss (EBL) (<50 ml) on subsequent elective dilation and curettage (D&C) procedure., Results: Eighteen patients (mean age, 32.8 ± 7.1 years) were included. Technical success and clinical success were experienced by 17/18 (94.4%) and 16/17 (94.1%) patients, respectively. Angiography demonstrated arteriovenous shunting in 18/18 (100%) patients, with early venous drainage. Seven of 18 (38.9%) patients underwent subsequent scheduled D&C due to remaining retained products of conception, with an EBL of 17.9 ± 15.6 ml. There was 1 minor complication of a self-limited vascular access groin hematoma (1/18, 5.6%) and 1 major complication (1/18, 5.6%) of a pulmonary embolism detected 3 days after UAE. The length of clinical follow-up was 19.3 ± 15.5 months, in which 41.2% (7/17) of the patients became pregnant., Conclusions: UAE with gelfoam alone for symptomatic uterine arteriovenous shunting is a feasible treatment option that has a high technical and clinical success rate with a low rate of complications., (Copyright © 2019 SIR. Published by Elsevier Inc. All rights reserved.)

Iridescence is an optical effect that produces angle dependent coloration in animals. Recently, studies have attempted to unveil structures behind such elaborated visual signals and associated behaviors in Odonata. Here, we studied males of the Amazonian damselfly Chalcopteryx scintillans, which have hindwings that exhibit pronounced iridescence. This optical feature is used by the damselflies for intra-specific communication during territorial fights and courtship. The main question we addressed was whether male wing structural coloration may predict the outcome of male-male contests. We also studied the wing ultrastructure, in order to reveal the mechanisms that are responsible for wing coloration. Using various microscopal and spectroscopal techniques, we demonstrate that hindwing coloration is derived from two main effects: (1) light interference in the cuticle multilayer and (2) a specific angle dependent light scattering and antireflective properties of the epicuticular wax coverage. The results of our field experiment show that wing pigmentation and the hue of the dorsal surface of the hindwings is correlated with the outcome of territorial contests. This is one of the first studies showing that structural coloration derived from multilayer interference may influence the outcome of intrasexual agonistic interactions. This indicates that multicomponent structural coloration in visually guided insects may be under selective forces of male-male competition for resources and females., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Objective: The objective of this study was to assess the impact of preprocedural time-out on workflow and patient safety in computed tomography (CT)-guided procedures., Methods: In this institutional review board-approved, Health Insurance Portability and Accountability Act-compliant study, preprocedure time-out was assessed by an independent observer in CT-guided procedures performed from January 16, 2018, to May 15, 2018. Anonymous survey of 302 radiology team members involved in image-guided procedures about preprocedure time-out was performed using REDCap., Results: Preprocedure time-out for 100 CT-guided procedures (biopsies, drainages, ablations) was observed. Procedures were recruited per observer availability and thus were nonconsecutive and nonrandom. Preprocedure time-out was performed in 100 procedures (100%). Median duration was 60 seconds (interquartile range, 60-71 seconds). Scripted checklist was followed in 52 cases (52/100, 52%). Omissions from the preprocedure time-out were identified in 40 cases (40/100, 40%) and were much more frequent when scripted checklist was not used (30/48 [63%] vs 10/52 [19%], P < 0.005). One case (1/100, 1%) was postponed due to abnormal coagulation parameters discovered during the time-out. Three cases (3/100, 3%) were delayed by 3 minutes to address other safety issues. In additional 14 cases (14/100, 14%), safety issues were raised during the time-out, which were resolved in less than 30 seconds.A total of 137 (45%) of 302 survey responses from 54 radiologists (39%), 55 technologists (40%), and 28 nurses (20%) were received. Forty-eight respondents (48/137, 35%) encountered a procedure that was cancelled or delayed as a result of information identified during time-out. Ninety-six percent (131/137) of respondents stated that time-out improves teamwork, 98% (134/137) stated that it enhances communication between the team members, and 93% (127/137) stated that it identifies and resolves problems and ambiguities., Conclusions: Scripted preprocedure time-out for CT-guided procedures takes approximately 1 minute to execute and detects safety issues in 18% of cases.

The cuticle plays an important role in the evolutionary success of insects. Many studies on insect cuticles have reported a soft, resilin-rich endocuticle. However, a recent study indicated the presence of a sclerotised endocuticle in the weevil Pachyrhynchus sarcitis kotoensis, which contradicts former knowledge. To understand the degree of sclerotisation in the endocuticle of the weevil and its potential function, we first examined the endocuticle by microscopic and staining techniques. We next performed mechanical tests to measure the material properties of the endocuticle, and numerical simulations to predict the structural effect of the sclerotisation. Our results provide the first evidence of the existence of a sclerotised endocuticle and its remarkable function in improving the mechanical stability of the cuticle. This study highlights the finding of a high degree of sclerotisation in the stiff endocuticle of the weevil, especially the matrix surrounding the fibres. This novel case brings new understanding of cuticle properties and gives promising insights into biomaterial design.

Objectives: To evaluate machine learning (ML) to detect chest CT examinations with dose optimization potential for quality assurance in a retrospective, cross-sectional study., Methods: Three thousand one hundred ninety-nine CT chest examinations were used for training and testing of the feed-forward, single hidden layer neural network (January 2016-December 2017, 60% male, 62 ± 15 years, 80/20 split). The model was optimized and trained to predict the volumetric computed tomography dose index (CTDI vol ) based on scan patient metrics (scanner, study description, protocol, patient age, sex, and water-equivalent diameter (D W )). The root mean-squared error (RMSE) was calculated as performance measurement. One hundred separate, consecutive chest CTs were used for validation (January 2018, 60% male, 63 ± 16 years), independently reviewed by two blinded radiologists with regard to dose optimization, and used to define an optimal cutoff for the model., Results: RMSE was 1.71, 1.45, and 1.52 for the training, test, and validation dataset, respectively. The scanner and D W were the most important features. The radiologists found dose optimization potential in 7/100 of the validation cases. A percentage deviation of 18.3% between predicted and actual CTDI vol was found to be the optimal cutoff: 8/100 cases were flagged as suboptimal by the model (range 18.3-53.2%). All of the cases found by the radiologists were identified. One examination was flagged only by the model., Conclusions: ML can comprehensively detect CT examinations with dose optimization potential. It may be a helpful tool to simplify CT quality assurance. CT scanner and D W were most important. Final human review remains necessary. A threshold of 18.3% between the predicted and actual CTDI vol seems adequate for CT quality assurance., Key Points: • Machine learning can be integrated into CT quality assurance to improve retrospective analysis of CT dose data. • Machine learning may help to comprehensively detect dose optimization potential in chest CT, but an individual review of the results by an experienced radiologist or radiation physicist is required to exclude false-positive findings.

Formulations for the controlled release of substances in the human terminal ileum and colon are essential to target the gut microbiome and its interactions with the intestinal mucosa. In contrast to pharmaceutical enteric coatings, reliable food-grade alternatives are still scarce. Shellac coatings have been used for various active ingredients, but their stability is affected by the physicochemical properties of the encapsulated substances. It is well known, that shellac release can be modulated by an acidic subcoating. Here, we hypothesized that a triple shellac coating with an adjusted intermediate coating (acidic or alkaline) can be effectively used to counteract the differences in pH value of various encapsulated substances, allowing a precise targeting of the desired release pH value. First, the system was tested with riboflavin 5'-monophosphate sodium salt dihydrate (RMSD) as a characteristic model substance. Secondly, it was transferred to nicotinic acid (NA) and nicotinamide (NAM) as bioactive compounds with different physio-chemical properties: NAM, an alkaline crystalline and highly water-soluble substance, led to a premature release from conventional shellac microcapsules, whereas RMSD and NA with their medium solubility and neutral to acidic pH properties delayed the shellac dissolution. A precise modulation of the release profile of each substance was possible by the addition of different intermediate subcoatings: an acidic layer with citric acid counteracted the premature release of the alkaline and highly soluble NAM. In contrast, an alkaline sodium bicarbonate intermediate subcoating enhanced shellac swelling and delayed the release of NA and RMSD. In conclusion, the novel triple-layer shellac coating provides a much higher adaptability and reliability for nutritional formulations aiming at a targeted release in the ileocolonic region., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Spiders attach silken threads to substrates by means of glue-coated nanofibers (piriform silk), spun into disc-like structures. The organization and ultrastructure of this nano-composite silk are largely unknown, despite their implications for the biomechanical function and material properties of thread anchorages. In this work, the ultrastructure of silken attachment discs was studied in representatives of four spider families with Transmission Electron Microscopy to facilitate a mechanistic understanding of piriform silk function across spiders. Based on previous findings from comparative studies of piriform silk gland morphology, we hypothesized that the fibre-glue proportion of piriform silk differs in different spiders, while the composition of fibre and glue fractions is consistent. Results confirmed large differences in the relative proportion of glue with low amounts in the orb weaver Nephila senegalensis (Araneidae) and the hunting spider Cupiennius salei (Ctenidae), larger amounts in the cobweb spider Parasteatoda tepidariorum (Theridiidae) and a complete reduction of the fibrous component in the haplogyne spider Pholcus phalangioides (Pholcidae). We rejected our hypothesis that glue ultrastructure is consistent. The glue is a colloid with polymeric and fluid fractions that strongly differ in proportions and assembly. We further confirmed that in all species studied both dragline and piriform silk fibres do not make contact with the environmental substrate. Instead, adhesion is established by a thin dense skin layer of the piriform glue. These results advance our understanding of piriform silk function and the interspecific variation of its properties, which is significant for spider biology, web function and the bioengineering of silk., (© 2019 Wiley Periodicals, Inc.)

Background: To evaluate the detection rate and image quality in CT-body-packer-screening at different radiation-dose levels and to determine a dose threshold that enables a reliable detection of incorporated body packs and incidental findings with a maximum of dose saving., Materials and Methods: We retrospectively included 27 individuals who underwent an abdominal CT with automated exposure control due to suspected body packing. CT images were reconstructed at different radiation-dose levels of 50%, 10, 5% and 1% using iterative reconstructions. All 135 CT reconstructions were evaluated by three independent readers. Reviewers determined the presence of foreign bodies and evaluated the image quality using a 5-point ranking scale. In addition, visualization of incidental findings was assessed., Results: A threshold of 5% (effective dose 0.11 ± 0.07 mSv) was necessary to correctly identify all 27 patients with suspected body packing. Extensive noise insertion to a dose level of 1% (0.02 ± 0.01 mSV) led to false-positive solid cocaine findings in three patients. Image quality was comparable between 100 and 50%. The threshold for correct identification of incidental findings was 10% of the initial dose (effective dose 0.21 ± 0.13 mSv)., Conclusions: Our results indicate that dose of abdominal CT for the detection of intracorporeal cocaine body packets can be markedly reduced to up to 5% of the initial dose while still providing sufficient image quality to detect ingested body packets. However, a minimum effective dose of 0.21 mSv (10% of initial dose) seems to be required to properly identify incidental findings.

Rationale and Objectives: To use an automatic computed tomography (CT) dose monitoring system to analyze the institutional chest and abdominopelvic CT dose data as regards the updated 2017 American College of Radiology (ACR) diagnostic reference levels (DRLs) based on water-equivalent diameter (Dw) and size-specific dose estimates (SSDE) to detect patient-size subgroups in which CT dose can be optimized., Materials and Methods: All chest CT examinations performed between July 2016 and April 2017 with and without contrast material, CT of the pulmonary arteries, and abdominopelvic CT with and without contrast material were included in this retrospective study. Dw and SSDE were automatically calculated for all scans using a previously validated in-house developed Matlab software and stored into our CT dose monitoring system. CT dose data were analyzed as regards the updated ACR DRLs (size groups: 21-25 cm, 25-29 cm, 29-33 cm, 33-37 cm, 37-41 cm). SSDE and volumetric computed tomography dose index (CTDIvol) were used as CT dose parameter., Results: Overall, 30,002 CT examinations were performed in the study period, 3860 of which were included in the analysis (mean age 62.1 ± 16.4 years, Dw 29.0 ± 3.3 cm; n = 577 chest CT without contrast material, n = 628 chest CT with contrast material, n = 346 CT of chest pulmonary, n = 563 abdominopelvic CT without contrast material, n = 1746 abdominopelvic CT with contrast material). Mean SSDE and CTDIvol relative to the updated DRLs were 43.3 ± 26.4 and 45.1 ± 27.9% for noncontrast chest CT, 52.3 ± 23.1 and 52.0 ± 23.1% for contrast-enhanced chest CT, 68.8 ± 29.5 and 70.0 ± 31.0% for CT of pulmonary arteries, 41.9 ± 29.2 and 43.3 ± 31.3% for noncontrast abdominopelvic CT, and 56.8 ± 22.2 and 58.8 ± 24.4% for contrast-enhanced abdominopelvic CT. Lowest dose compared to the DRLs was found for the Dw group of 21-25 cm in noncontrast abdominopelvic CT (SSDE 30.4 ± 21.8%, CTDIvol 30.8 ± 21.4%). Solely the group of patients with a Dw of 37-41 cm undergoing noncontrast abdominopelvic CT exceeded the ACR DRL (SSDE 100.3 ± 59.0%, CTDIvol 107.1 ± 63.5%)., Conclusions: On average, mean SSDE and CTDIvol of our institutional chest and abdominopelvic CT protocols were lower than the updated 2017 ACR DRLs. Size-specific subgroup analysis revealed a wide variability of SSDE and CTDIvol across CT protocols and patient size groups with a transgression of DRLs in noncontrast abdominopelvic CT of large patients (Dw 37-41 cm)., (Copyright © 2018 The Association of University Radiologists. Published by Elsevier Inc. All rights reserved.)

Adult dragonflies can be divided into two major groups, perchers and fliers, exhibiting notably different flight behaviour. Previous studies have yielded conflicting results regarding the link between the wing macro-morphology and flight style in these two groups. In this study, we present the first systematic investigation of the micro-morphological differences of wings of percher and flier dragonflies in four closely related species from the family Libellulidae. Our results suggest that the shape and material composition of wing microstructural components and, in particular, the nodus are adapted to facilitate the specific wing functioning in fliers and perchers. The findings further indicate a decreasing trend in the area proportion of the soft resilin-dominated cuticle in the nodus in the series of species from typical perchers to typical fliers. Such a reduction in the resilin proportion in the nodus of fliers is associated with an increase in the wing aspect ratio. The knot-shaped protrusion at the nodus of perchers, which becomes notably smaller in that of strong fliers, is likely to act as a mechanical stopper, avoiding large wing displacements. This study aims to develop a novel framework for future research on the relationship between wing morphology and flight behaviour in dragonflies., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

Aim: To evaluate the implementation of the updated computed tomography (CT) diagnostic reference levels (DRLs) from the German Federal Office for Radiation Protection into clinical routine using an automatic CT dose monitoring system., Methods and Materials: CT radiation exposure was analysed before and after implementing the updated national DRLs into routine clinical work in 2016. After the implementation process, institutional CT protocols were mapped to the anatomical regions for which DRLs were provided. Systematically, protocols that exceeded the thresholds were optimised and analysed in detail. The CT radiation output parameters analysed were volumetric CT dose index (CTDIvol) and dose-length product (DLP). Three radiologists evaluated subjective image quality using a three-point Likert scale., Results: The study included 94,258 CT series (from 27,103 CT examinations) in adult patients performed in 2016. When averaged over all body regions with available DRL, institutional CTDIvol/DLP values were always below the DRLs (65.2±32.9%/67.3±41.5% initially; 59.4±32%/60.5±39.9% after optimisation). Values exceeding the national DRLs were found for pelvis (n=268; CTDIvol 107.7±65.7%/DLP 106.3±79.3%), lumbar spine (n=91; 160.8±74.7%/175.2±104.1%), and facial bones (n=527; 108±39%/152.7±75.7%). After optimisation, CTDIvol and DLP were 87.9±73%/87.8±80.8% for the pelvis, 67.8±33.2%/74.5±50.6% for the lumbar spine and 95.1±45.8%/133.3±74.6% for the viscerocranium., Conclusion: An automatic CT dose monitoring system enabled not only comprehensive monitoring of a DRL implementation process but can also help to optimise radiation exposure., (Copyright © 2018 The Royal College of Radiologists. Published by Elsevier Ltd. All rights reserved.)

Size-specific institutional diagnostic reference levels (DRLs) were generated for chest and abdominopelvic computed tomography (CT) based on size-specific dose estimates (SSDEs) and depending on patients' water-equivalent diameter (Dw). 1690 CT examinations were included in the IRB-approved retrospective study. SSDEs based on the mean water-equivalent diameter of the entire scan volume were calculated automatically. SSDEs were analyzed for different patient sizes and institutional DRLs (iDRLS; 75% percentiles) based on Dw and SSDEs were generated. iDRLs were compared to the national DRLs. Mean volumetric computed tomography dose index (CTDIvol), Dw and SSDEs for all 1690 CT examinations were 7.2 ± 4.0 mGy (0.84-47.9 mGy), 29.0 ± 3.4 cm and 8.5 ± 3.8 mGy (1.2-37.7 mGy), respectively. Overall, the mean SSDEs of all CT examinations were higher than the CTDIvol in chest CT, abdominopelvic CT and upper abdominal CT, respectively (p < 0.001 for all). There was a strong linear correlation between Dw and SSDEs in chest (R 2  = 0.66), abdominopelvic (R 2  = 0.98) and upper abdominal CT (R 2  = 0.96) allowing for the implementation of size-specific institutional DRLs based on SSDEs and patients' Dw. We generated size-specific, Dw-dependent institutional DRLs based on SSDEs, which allow for easier and more comprehensive analyses of CT radiation exposure. Our results indicate that implementation of SSDEs into national DRLs may be beneficial.

Objective: Gut microbiota represent a potential novel target for future prediabetes and type 2 diabetes therapies. In that respect, niacin has been shown to beneficially affect the host-microbiome interaction in rodent models., Research Design and Methods: We characterized more than 500 human subjects with different metabolic phenotypes regarding their niacin (nicotinic acid [NA] and nicotinamide [NAM]) status and their gut microbiome. In addition, NA and NAM delayed-release microcapsules were engineered and examined in vitro and in vivo in two human intervention studies (bioavailability study and proof-of-concept/safety study)., Results: We found a reduced α-diversity and Bacteroidetes abundance in the microbiome of obese human subjects associated with a low dietary niacin intake. We therefore developed delayed-release microcapsules targeting the ileocolonic region to deliver increasing amounts of NA and NAM to the microbiome while preventing systemic resorption to avoid negative side effects (e.g., facial flushing). In vitro studies on these delayed-release microcapsules revealed stable conditions at pH 1.4, 4.5, and 6.8, followed by release of the compounds at pH 7.4, simulating the ileocolonic region. In humans in vivo, gut-targeted delayed-release NA but not NAM produced a significant increase in the abundance of Bacteroidetes . In the absence of systemic side effects, these favorable microbiome changes induced by microencapsulated delayed-release NA were associated with an improvement of biomarkers for systemic insulin sensitivity and metabolic inflammation., Conclusion: Targeted microbiome intervention by delayed-release NA might represent a future therapeutic option for prediabetes and type 2 diabetes., (© 2017 by the American Diabetes Association.)

The elytral surface of dung beetles is generally accepted to be self-cleaning due to its anti-adhesive properties. In this article, the wettability and adhesive properties of elytral surface (intact and treated with Acetone and Ethanol) of the beetle Geotrupes stercorarius were characterized. Since these properties are influenced by the surface structure and chemistry, the micro- and nanostructure of the elytra were observed using scanning electron microscopy and the surface roughness were estimated with white light interferometery, whereas the water contact angle and adhesion force of the elytra were evaluated using contact angle measurement device and force transducer, respectively. The results show that the microstructure of the elytra changed greatly after different chemical treatments and the changes in wettability were mainly related to the changes of elytra roughness after treatments. The differences in adhesion force between differently treated elytra and wet sand indicate that the molecular polarity of the elytral surface is decisive for its anti-adhesive (self-cleaning) property.

Dragonfly wings are highly specialized locomotor systems, which are formed by a combination of several structural components. The wing components, also known as structural elements, are responsible for the various aspects of the wing functionality. Considering the complex interactions between the wing components, modelling of the wings as a whole is only possible with inevitable huge oversimplifications. In order to overcome this difficulty, we have recently proposed a new approach to model individual components of complex wings comparatively. Here, we use this approach to study nodus, a structural element of dragonfly wings which has been less studied to date. Using a combination of several imaging techniques including scanning electron microscopy (SEM), wide-field fluorescence microscopy (WFM), confocal laser scanning microscopy (CLSM) and micro-computed tomography (micro-CT) scanning, we aim to characterize the spatial morphology and material composition of fore- and hindwing nodi of the dragonfly Brachythemis contaminata. The microscopy results show the presence of resilin in the nodi, which is expected to help the deformability of the wings. The computational results based on three-dimensional (3D) structural data suggest that the specific geometry of the nodus restrains its displacements when subjected to pressure on the ventral side. This effect, resulting from an interlocking mechanism, is expected to contribute to the dorso-ventral asymmetry of wing deformation and to provide a higher resistance to aerodynamic forces during the downstroke. Our results provide an important step towards better understanding of the structure-property-function relationship in dragonfly wings., Statement of Significance: In this study, we investigate the wing nodus, a specialized wing component in dragonflies. Using a combination of modern imaging techniques, we demonstrate the presence of resilin in the nodus, which is expected to facilitate the wing deformability in flight. The specific geometry of the nodus, however, seems to restrain its displacements when subjected to pressure on the ventral side. This effect, resulting from an interlocking mechanism, is suggested to contribute to dorso-ventral asymmetry of wing deformations and to provide a higher resistance to aerodynamic forces during the downstroke. Our results provide an important step towards better understanding of the structure-property-function relationship in dragonfly wings and might help to design more efficient wings for biomimetic micro-air vehicles., (Copyright © 2017 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.)

Maintaining posture requires tight regulation of the position and orientation of numerous spinal components. Yet, surprisingly little is known about this regulatory mechanism, whose failure may result in spinal deformity as in adolescent idiopathic scoliosis. Here, we use genetic mouse models to demonstrate the involvement of proprioception in regulating spine alignment. Null mutants for Runx3 transcription factor, which lack TrkC neurons connecting between proprioceptive mechanoreceptors and spinal cord, developed peripubertal scoliosis not preceded by vertebral dysplasia or muscle asymmetry. Deletion of Runx3 in the peripheral nervous system or specifically in peripheral sensory neurons, or of enhancer elements driving Runx3 expression in proprioceptive neurons, induced a similar phenotype. Egr3 knockout mice, lacking muscle spindles, but not Golgi tendon organs, displayed a less severe phenotype, suggesting that both receptor types may be required for this regulatory mechanism. These findings uncover a central role for the proprioceptive system in maintaining spinal alignment., (Copyright © 2017 Elsevier Inc. All rights reserved.)

Some consider that the first winged insects had living tissue inside the wing membrane, resembling larval gills or developing wing pads. However, throughout the developmental process of the wing membrane of modern insects, cells and tracheoles in the lumen between dorsal and ventral cuticle disappear and both cuticles become fused. This process results in the rather thin rigid stable structure of the membrane. The herewith described remarkable case of the dragonfly Zenithoptera lanei shows that in some highly specialized wings, the membrane can still be supplemented by tracheae. Such a characteristic of the wing membrane presumably represents a strong specialization for the synthesis of melanin-filled nanolayers of the cuticle, nanospheres inside the wing membrane and complex arrangement of wax crystals on the membrane surface, all responsible for unique structural coloration., (© 2017 The Author(s).)

The peculiar phenomenon of hyper-elongation of intromittent organs is well known in a number of insect groups. However, the unresolved questions of how and why such a phenomenon originated independently many times continue to attract biologists' attention. To be able to detect the evolutionary driving mechanisms that enabled insects to repeatedly acquire such a peculiarity, first of all the structural key features and the mechanics of these organs have to be determined. In the present study, the morphology of the reproductive organs of two species of the beetle genus Cassida, with a special focus on the male structures, was scrutinised in detail during copulation and at rest using different microscopy techniques. We found that the hyper-elongated structure of the intromittent organ, called flagellum, is part of the male ejaculatory duct. When the flagellum is inserted into the female spermathecal duct, longitudinal muscles of the ejaculatory duct, but not the flagellum, are shortened. These results strongly suggest that the contraction of the longitudinal muscles of the ejaculatory duct causes propulsion of the flagellum into the highly spiralled spermathecal duct of the female. The tip of the cuticular flagellum is curled up, which can suggest that its physical properties differ from those of the rest of the flagellum. Considering the preceding modelling studies, this property aids the flagellum in penetrating within the highly spiralled and very variable female duct. Based on our morphological results and in comparison with the morphology of intromittent organs of other beetles, we discuss the evolutionary origin of the hyper-elongation in the Cassida species and propose a hypothesis that explains the independent origin of the hyper-elongation of intromittent organs., (Copyright © 2016 Elsevier GmbH. All rights reserved.)

The Runx3 transcription factor is essential for development and diversification of the dorsal root ganglia (DRGs) TrkC sensory neurons. In Runx3-deficient mice, developing TrkC neurons fail to extend central and peripheral afferents, leading to cell death and disruption of the stretch reflex circuit, resulting in severe limb ataxia. Despite its central role, the mechanisms underlying the spatiotemporal expression specificities of Runx3 in TrkC neurons were largely unknown. Here we first defined the genomic transcription unit encompassing regulatory elements (REs) that mediate the tissue-specific expression of Runx3. Using transgenic mice expressing BAC reporters spanning the Runx3 locus, we discovered three REs-dubbed R1, R2, and R3-that cross-talk with promoter-2 (P2) to drive TrkC neuron-specific Runx3 transcription. Deletion of single or multiple elements either in the BAC transgenics or by CRISPR/Cas9-mediated endogenous ablation established the REs' ability to promote and/or repress Runx3 expression in developing sensory neurons. Our analysis reveals that an intricate combinatorial interplay among the three REs governs Runx3 expression in distinct subtypes of TrkC neurons while concomitantly extinguishing its expression in non-TrkC neurons. These findings provide insights into the mechanism regulating cell type-specific expression and subtype diversification of TrkC neurons in developing DRGs., (© 2016 Appel et al.; Published by Cold Spring Harbor Laboratory Press.)

With the increasing number of vehicles and the development of transport systems, traffic contamination has become an important source of current environmental pollution. The study of roadside distribution patterns of traffic-related contaminants and its influencing factors can contribute to assess the scope and distribution process of the contaminants. A large number of works confirmed that magnetic methods which are fast and economic can be used to indicate the traffic-related pollution. Based on the previous study, we installed two new monitoring sites and conducted repeated in situ measurements of magnetic susceptibility (κ). From these data, we calculated the accumulation amount and accumulation rate of κ to reveal the detailed distribution process of traffic contaminants on the roadside surface over time. In addition, we collected daily meteorological data (rainfall and wind direction) and conducted a correlation analysis between the accumulation rate of κ and the meteorological data. The results show that the accumulation rate of traffic contaminants on the roadside surface is lower in periods of higher rainfall, and that the winds influence the distribution pattern of contaminants through changing their transmission path. The results confirm that magnetic methods can be used to reveal the detailed distribution process of traffic-related contaminants and its influencing factors.

Resilin is an elastomeric protein typically occurring in exoskeletons of arthropods. It is composed of randomly orientated coiled polypeptide chains that are covalently cross-linked together at regular intervals by the two unusual amino acids dityrosine and trityrosine forming a stable network with a high degree of flexibility and mobility. As a result of its molecular prerequisites, resilin features exceptional rubber-like properties including a relatively low stiffness, a rather pronounced long-range deformability and a nearly perfect elastic recovery. Within the exoskeleton structures, resilin commonly forms composites together with other proteins and/or chitin fibres. In the last decades, numerous exoskeleton structures with large proportions of resilin and various resilin functions have been described. Today, resilin is known to be responsible for the generation of deformability and flexibility in membrane and joint systems, the storage of elastic energy in jumping and catapulting systems, the enhancement of adaptability to uneven surfaces in attachment and prey catching systems, the reduction of fatigue and damage in reproductive, folding and feeding systems and the sealing of wounds in a traumatic reproductive system. In addition, resilin is present in many compound eye lenses and is suggested to be a very suitable material for optical elements because of its transparency and amorphousness. The evolution of this remarkable functional diversity can be assumed to have only been possible because resilin exhibits a unique combination of different outstanding properties.

Purpose: Children's Oncology Group study AHOD03P1 was designed to determine whether excellent outcomes can be maintained for patients with low-risk, pediatric lymphocyte-predominant Hodgkin lymphoma (LPHL) with a strategy of resection alone or minimal chemotherapy., Patients and Methods: Patients with stage IA LPHL in a single node that was completely resected were observed without further therapy; recurrences were treated with three cycles of doxorubicin/vincristine/prednisone/cyclophosphamide (AV-PC). Patients with unresected stage IA or stage IIA LPHL were treated with three cycles of AV-PC. Patients with less than a complete response (CR) to AV-PC received 21-Gy involved-field radiation therapy (IFRT)., Results: A total of 183 eligible patients were enrolled; 178 were evaluable. Of these, 52 patients underwent complete resection of a single node. There were 13 relapses at a median of 11.5 months; 5-year event-free survival (EFS) was 77% (range, 62% to 87%). A total of 135 patients received AV-PC; 126 were treated at diagnosis and nine at relapse after surgery alone. Eleven patients receiving AV-PC had less than CR and received IFRT. Fourteen first events occurred among 135 patients (12 relapses and two second malignancies). Two relapses occurred in patients who had received IFRT. Five-year EFS was 88.8% (95% CI, 81.8% to 93.2%). Five-year EFS for the entire cohort was 85.5% (95% CI, 79.2% to 90.1%); overall survival was 100%., Conclusion: Some 75% of highly selected pediatric patients with LPHL may be spared chemotherapy after surgical resection alone. Pediatric LPHL has excellent EFS with chemotherapy that is less intensive than standard regimens; > 90% of patients can avoid radiation therapy. The salvage rate for the few relapses is high, with 100% survival overall., (© 2016 by American Society of Clinical Oncology.)

Dragonfly wings are known as biological composites with high morphological complexity. They mainly consist of a network of rigid veins and flexible membranes, and enable insects to perform various flight manoeuvres. Although several studies have been done on the aerodynamic performance of Odonata wings and the mechanisms involved in their deformations, little is known about the influence of vein joints on the passive deformability of the wings in flight. In this article, we present the first three-dimensional finite-element models of five different vein joint combinations observed in Odonata wings. The results from the analysis of the models subjected to uniform pressures on their dorsal and ventral surfaces indicate the influence of spike-associated vein joints on the dorsoventral asymmetry of wing deformation. Our study also supports the idea that a single vein joint may result in different angular deformations when it is surrounded by different joint types. The developed numerical models also enabled us to simulate the camber formation and stress distribution in the models. The computational data further provide deeper insights into the functional role of resilin patches and spikes in vein joint structures. This study might help to more realistically model the complex structure of insect wings in order to design more efficient bioinspired micro-air vehicles in future.

Insect wing veins are biological composites of chitin and protein arranged in a complex lamellar configuration. Although these hierarchical structures are found in many 'venous wings' of insects, very little is known about their physical and mechanical characteristics. For the first time, we carried out a systematic comparative study to gain a better understanding of the influence of microstructure on the mechanical characteristics and damping behaviour of the veins. Morphological data have been used to develop a series of three-dimensional numerical models with different material properties and geometries. Finite-element analysis has been employed to simulate the mechanical response of the models under different loading conditions. The modelling strategy used in this study enabled us to determine the effects selectively induced by resilin, friction between layers, shape of the cross section, material composition and layered structure on the stiffness and damping characteristics of wing veins. Numerical simulations suggest that although the presence of the resilin-dominated endocuticle layer results in a much higher flexibility of wing veins, the dumbbell-shaped cross section increases their bending rigidity. Our study further shows that the rubber-like cuticle, friction between layers and material gradient-based design contribute to the higher damping capacity of veins. The results of this study can serve as a reference for the design of novel bioinspired composite structures.