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Few studies have investigated risk factors for recurrence of blunt traumatic abdominal wall hernias (TAWH).Twenty trauma centers identified repaired TAWH from January 2012 to December 2018. Logistic regression was used to investigate risk factors for recurrence.TAWH were repaired in 175 patients with 21 (12.0%) known recurrences. No difference was found in location, defect size, or median time to repair between the recurrence and non-recurrence groups. Mesh use was not protective of recurrence. Female sex, injury severity score (ISS), emergency laparotomy (EL), and bowel resection were associated with hernia recurrence. Bowel resection remained significant in a multivariable model.Female sex, ISS, EL, and bowel resection were identified as risk factors for hernia recurrence. Mesh use and time to repair were not associated with recurrence. Surgeons should be mindful of these risk factors but could attempt acute repair in the setting of appropriate physiologic parameters.

Reproductive coercion is an understudied form of intimate partner violence (IPV) that occurs when a person attempts to control the autonomous reproductive decision making of their intimate partner. Previous research has demonstrated that individuals who experience reproductive coercion are more likely to experience other forms of IPV (e.g., physical and sexual). Research has also shown that Black/African American and Latinx/Hispanic individuals are at an increased risk of experiencing reproductive coercion compared to their White/Non-Hispanic peers. However, most of the research on reproductive coercion has been conducted in family-planning clinics where IPV is reported at a higher rate than in community samples. Thus, using a diverse community sample of female-identifying young adults ( N = 370) who were recruited as part of an ongoing longitudinal study on dating violence, we examined the prevalence of lifetime reproductive coercion and its relationship with other forms of IPV, as well as the differences in prevalence among racial and ethnic groups. Lifetime prevalence of being victimized by any form of reproductive coercion was 11.4%. Results indicated that individuals who experienced reproductive coercion were more likely to experience physical and sexual IPV relative to those who did not experience reproductive coercion. With respect to race/ethnicity, 5.6% of White participants, 10.5% of Black/African American participants, and 14.8% of Hispanic/Latinx participants reported experiencing reproductive coercion. Chi-square analyses showed Hispanic/Latinx participants had a significantly higher prevalence of reproductive coercion when compared to White/Non-Hispanic participants. These findings suggest a need for additional research on culturally-specific risk and protective factors related to reproductive coercion among Hispanic/Latinx individuals to identify potential intervention and prevention strategies.

Several studies link adverse childhood experiences (ACEs) to delinquency. Yet, developmental sequalae accounting for this association remain unclear, with previous research limited by cross-sectional research designs and investigations of singular mediating processes. To redress these shortcomings, this study examines the longitudinal association between ACEs and delinquency as mediated by both sleep problems and low self-control, two factors which past research implicates as potentially important for understanding how ACEs contribute to antisocial behavior. Data collected from 480 adolescents (71.3% boys; 86.3% White) and their parents participating in the Michigan Longitudinal Study was used to conduct a serial mediation analysis. The association between ACEs (prior to age 11) and delinquency in late adolescence was found to operate indirectly via sleep problems in early adolescence and low self-control in middle adolescence. Nonetheless, a direct association between ACEs and later delinquency remained. Pathways through which ACEs contribute to later delinquency are complex and multiply determined. Findings indicate that early behavioral interventions, including improving sleep and self-control, could reduce later delinquency. Still, more research is needed to identify additional avenues through which the ACEs–delinquency association unfolds across development.

Tendon degeneration is typically described as an overuse injury with little distinction made between magnitude of load (overload) and number of cycles (overuse). Further, in vivo animal models of tendon degeneration are mostly overuse models, where tendon damage is caused with high number of load cycles. As a result, there is a lack of knowledge of how isolated overload leads to degeneration. A surgical model of synergist ablation (SynAb) overloads the target tendon, plantaris, by ablating its synergist tendon, Achilles. The objective of this study was to evaluate the structural and functional changes that occur following overload of plantaris tendon in a rat SynAb model. Tendon cross-sectional area and shape changes were evaluated by longitudinal MR imaging up to 8-weeks post-surgery. Tissue-scale structural changes were evaluated by semi-quantified histology and second harmonic generation microscopy. Fibril level changes were evaluated with Serial Block Face Scanning Electron Microscopy (SBF-SEM). Functional changes were evaluated using tension tests at the tissue and microscale using a custom testing system allowing both video and microscopy imaging. At 8 weeks, overloaded plantaris tendons exhibited degenerative changes including increases in CSA, cell density, collagen damage area fraction, and fibril diameter, and decreases in collagen alignment, modulus, and yield stress. To interpret the differences between overload and overuse in tendon, we introduce a new framework for tendon remodeling and degeneration that differentiates between the inputs of overload and overuse. In summary, isolated overload induces multiscale degenerative structural and functional changes in plantaris tendon.

Fused Deposition Modeling (FDM) is one of the most common polymer 3D printing technologies used in many applications today. However, limited volume capacity for 3D printing large parts or components is the usual downside of this technology, especially desktop 3D printers. Hence, to offset this limitation, the 3D-printed parts are often designed in multiple pieces and assembled after printing, which requires post-processing called cold welding. Such welds are also quite strong but not as strong as a single-piece print. Therefore, finding suitable parameters or settings that can provide substantial strength for cold-welded 3D-printed parts will be beneficial. This study aims to determine the failing behavior and shear strength of ABS FDM 3D-printed single-lap joint using ABS glue as adhesive. Specimens were printed with varying raster angles (+45o/-45o and 0o/90o) and layer thickness (290 μm, 190 μm, and 90 μm) to investigate the effects on the adhesion or shear strength and failure mode of the acetone welded 3D-printed joints. Results show that raster angle and layer thickness significantly affected the shear strength of acetone welded materials. Single-lap joint test sample printed with +45o/-45o raster angle reveals higher shear strength than specimens printed with 0o/90o raster angle. Results also indicated that the gaps between the raster and voids between adjacent filaments of 3D-printed parts affects the adhesion and failure mode of a single-lap joint.

3D printing is now being used in many different applications. This adoption of 3D printing in these applications is accelerated by the development of new materials such as high performance polymers and nanocomposites. In this study, a commercially-available stereolithographic (SLA) resin has been reinforced with 0%, 0.1%, 0.3% and 0.5% nanosilica powder. The resulting mixture has been 3D-printed using a stereolithography 3d printer. The 3D-printed composites have been post-cured in a UV chamber and the mechanical properties have been assessed under compressive loading using a universal testing machine (ASTM-D695). The results show that adding nanosilica powder to the resin would increase the compressive strength of the resin, and that the highest compressive strength could be observed when 0.1% nanosilica poweder was added to the resin.

Nearly two decades since the detection of cyclopropenone (c-C3H2O) in the interstellar medium (ISM), the understanding of how this molecule comes to be remains incomplete. Many hypotheses place the ubiquitous hydrocarbon c-C3H2 at the centre of such discussions. However, insights into c-C3H2 chemistry are further complicated by the recent detection of ethynyl cyclopropenylidene (c-C3HC2H) and the observation of a radio line possibly belonging to methylenecyclopropene (c-C3H2CH2). In a necessary reconciliation of past and current work on the chemical capabilities of c-C3H2 in interstellar environments, the formation pathways of several functionalized cyclopropenes from c-C3H2 and a hydrogenated radical are explored. Chemically accurate CCSD(T)-F12/cc-pVTZ-F12 calculations are used to evaluate the energies of reaction and generate structures along the reaction pathway for formation products deemed chemically plausible. Potential energy scans are used to include or rule out certain paths to product formation based on conformation to the necessary requirements of cold interstellar chemistry. Four functionalized cyclopropenes in addition to c-C3H2O have net exothermic reactions when forming from c-C3H2 (c-C3H2CC, c-C3H2S, c-C3H2NH, and c-C3H2CH2). The former three are found to have reaction profiles favourable for formation in the cold ISM, while c-C3H2CH2 can only form by passage through an association barrier that must be mitigated by an energy source of some kind. c-C3H2S and c-C3H2NH are the best candidates for new spectroscopic searches. A complete detection of c-C3H2CH2 is necessary to fully understand cyclopropenylidene chemistry in the ISM.

The ataxia telangiectasia and Rad3-related (ATR) checkpoint kinase 1 (CHK1) pathway is intricately involved in protecting the integrity of the human genome by suppressing replication stress and repairing DNA damage. ATR is a promising therapeutic target in cancer cells because its inhibition could lead to an accumulation of damaged DNA preventing further replication and division. ATR inhibition is being studied in multiple types of cancer, including advanced urothelial carcinoma where there remains an unmet need for novel therapies to improve outcomes. Herein, we review preclinical and clinical data evaluating 4 ATR inhibitors as monotherapy or in combination with chemotherapy. The scope of this review is focused on contemporary studies evaluating the application of this novel therapy in advanced urothelial carcinoma.

We use a nonlinear reduction in a bank's check-cashing fees and variation in regulated check-clearing times to identify the elasticity of demand for cashing checks rather than depositing them. We find that an extra day of check-clearing time makes account holders 65.5% more likely to cash a check than deposit it, which implies they are willing to pay $11.17 per day for faster access to their funds – an effective annualized discount rate of 11,054% for the average check. We use this elasticity to evaluate recent proposals that mandate faster check-clearing times.

During human pregnancy the chorion (fetal) lines decidua (maternal) creating the feto–maternal interface. Despite their proximity, resident decidual immune cells remain quiescent during gestation and do not invade the chorion. Infection and infiltration of activated immune cells toward the chorion are often associated with preterm birth. However, the mechanisms that maintain choriodecidual immune homeostasis or compromise immune barrier functions remain unclear. To understand these processes, a two-chamber microphysiological system (MPS) was created to model the human choriodecidual immune interface under normal and infectious conditions in vitro. This MPS has outer (fetal chorion trophoblast cells) and inner chambers (maternal decidual + CD45+ cells [70:30 ratio]) connected by microchannels. Decidual cells were treated with LPS to mimic maternal infection, followed by immunostaining for HLA-DR and HLA-G, immune panel screening by imaging cytometry by time of flight, and immune regulatory factors IL-8 and IL-10, soluble HLA-G, and progesterone (ELISA). LPS induced a proinflammatory phenotype in the decidua characterized by a decrease in HLA-DR and an increase in IL-8 compared with controls. LPS treatment increased the influx of immune cells into the chorion, indicative of chorionitis. Cytometry by time of flight characterized immune cells in both chambers as active NK cells and neutrophils, with a decrease in the abundance of nonproinflammatory cytokine-producing NK cells and T cells. Conversely, chorion cells increased progesterone and soluble HLA-G production while maintaining HLA-G expression. These results highlight the utility of MPS to model choriodecidual immune cell infiltration and determine the complex maternal–fetal crosstalk to regulate immune balance during infection.

Small bowel obstructions (SBOs) are surgical emergencies that can occur with mechanical blockage of the intestinal lumen. These blockages are most commonly caused by adhesions or hernias, but can also result from intestinal neoplasms. This case report documents the rare occurrence of SBO due to a submucosal leiomyoma. This case was complicated by the patient’s longstanding history of Crohn’s disease, which has a considerable overlap in symptomatology with SBOs. This may have resulted in a delay in the patient’s diagnosis. Leiomyomas should always be considered as a potential, albeit rare, cause of SBO.

External spacecraft materials play an important role in satellite protection from the harsh space environment. Research has shown that the physical, chemical, and optical properties of matter change continuously as a result of exposure to solar radiation and aggressive chemical species produced in Earth’s upper atmosphere. Thorough knowledge of the material properties’ evolution throughout a planned mission lifetime helps to improve the reliability of spacecraft. Moreover, the establishment of correlation factors between true space exposure and accelerated space weather experiments at ground facilities enables accurate prediction of on-orbit material performance based on laboratory-based testing. The presented work aims to evaluate the radiation effects of a low-Earth-orbit environment, namely, exposure to the high-energy electrons and atomic oxygen (AO) of heritage and novel spacecraft material selection. The studied materials represent the “flight duplicates” of samples that are launched as a part of the 16th Materials International Space Station Experiment Flight Facility (MISSE-FF) mission in 2022.

Despite the advancement of machine learning techniques in recent years, state-of-the-art systems lack robustness to "real world" events, where the input distributions and tasks encountered by the deployed systems will not be limited to the original training context, and systems will instead need to adapt to novel distributions and tasks while deployed. This critical gap may be addressed through the development of "Lifelong Learning" systems that are capable of 1) Continuous Learning, 2) Transfer and Adaptation, and 3) Scalability. Unfortunately, efforts to improve these capabilities are typically treated as distinct areas of research that are assessed independently, without regard to the impact of each separate capability on other aspects of the system. We instead propose a holistic approach, using a suite of metrics and an evaluation framework to assess Lifelong Learning in a principled way that is agnostic to specific domains or system techniques. Through five case studies, we show that this suite of metrics can inform the development of varied and complex Lifelong Learning systems. We highlight how the proposed suite of metrics quantifies performance trade-offs present during Lifelong Learning system development - both the widely discussed Stability-Plasticity dilemma and the newly proposed relationship between Sample Efficient and Robust Learning. Further, we make recommendations for the formulation and use of metrics to guide the continuing development of Lifelong Learning systems and assess their progress in the future., Comment: To appear in Neural Networks

Non-invasive small-animal imaging technologies, such as optical imaging, magnetic resonance imaging and x-ray computed tomography, have enabled researchers to study normal biological phenomena or disease progression in their native conditions. However, existing small-animal imaging technologies often lack either the penetration capability for interrogating deep tissues (e.g., optical microscopy), or the functional and molecular sensitivity for tracking specific activities (e.g., magnetic resonance imaging). To achieve functional and molecular imaging in deep tissues, we have developed an integrated photoacoustic, ultrasound and angiographic tomography (PAUSAT) system by seamlessly combining light and ultrasound in a non-invasive manner. PAUSAT can perform three imaging functions simultaneously with complementary contrast: high-frequency B-mode ultrasound imaging of tissue morphology, microbubble-enabled acoustic angiography of vasculature, and multi-spectral photoacoustic imaging of molecular probes. PAUSAT can provide three-dimensional (3D) multi-contrast images that are automatically co-registered, with high spatial resolutions at large depth. Using PAUSAT, we conducted proof-of-concept in vivo experiments on various small animal models: monitoring longitudinal development of placenta and embryo during mouse pregnancy, tracking biodistribution and metabolism of near-infrared organic dye on the whole-body scale, and detecting genetically-encoded breast tumor expressing photoswitchable phytochromes. These results have collectively demonstrated that PAUSAT has broad applicability in biomedical research, providing comprehensive structural, functional, and molecular imaging of small animal models.

The Additive Manufacturing or 3D printing technology gives an unmatched flexibility and innovative solution to different problems of various industries, including maritime industry. Even though the application of this technology is mainly used in the manufacturing and shipbuilding sector of the industry, it is now also being used by some maritime schools or institutions, like the Maritime Academy of Asia and the Pacific (MAAP). Thus, this paper presents the recent applications of 3D printing in maritime industry, as a whole, and in the academe. The 3D printed projects created by MAAP faculty and students will also be demonstrated and discussed in this paper. Lastly, future perspectives on the application of 3D printing technology in maritime education, like what will be the possible impact if it was included in their curriculum, will be presented as well.

Glioblastoma (GBM) constitutes the most lethal primary brain tumor for which immunotherapy has provided limited benefit. The unique brain immune landscape is reflected in a complex tumor immune microenvironment (TIME) in GBM. Here, single-cell sequencing of the GBM TIME revealed that microglia were under severe oxidative stress, which induced nuclear receptor subfamily 4 group A member 2 (NR4A2)–dependent transcriptional activity in microglia. Heterozygous Nr4a2 (Nr4a2+/−) or CX3CR1+ myeloid cell–specific Nr4a2 (Nr4a2fl/flCx3cr1Cre) genetic targeting reshaped microglia plasticity in vivo by reducing alternatively activated microglia and enhancing antigen presentation capacity for CD8+ T cells in GBM. In microglia, NR4A2 activated squalene monooxygenase (SQLE) to dysregulate cholesterol homeostasis. Pharmacologic NR4A2 inhibition attenuated the protumorigenic TIME, and targeting the NR4A2 or SQLE enhanced the therapeutic efficacy of immune-checkpoint blockade in vivo. Collectively, oxidative stress promotes tumor growth through NR4A2–SQLE activity in microglia, informing novel immune therapy paradigms in brain cancer. Significance: Metabolic reprogramming of microglia in GBM informs synergistic vulnerabilities for immune-checkpoint blockade therapy in this immunologically cold brain tumor. This article is highlighted in the In This Issue feature, p. 799

Transcription is the critical first step in expressing a gene, during which an RNA polymerase (RNAP) synthesizes an RNA copy of one strand of the DNA that encodes a gene. Here we describe a laboratory experiment that uses a single assay to probe two important steps in transcription: (1) RNAP binding to DNA, and (2) the transcriptional activity of the polymerase. Students probe both these steps in a single experiment using a fluorescence-based electrophoretic mobility shift assay (EMSA) and commercially available Escherichia coli RNAP. As an inquiry-driven component, students add the transcriptional inhibitor rifampicin to reactions and draw conclusions about its mechanism of inhibition by determining whether it blocks polymerase binding to DNA or transcriptional activity. Depending on the curriculum and learning goals of individual courses, this experimental module could be easily expanded to include additional experimentation that mimics a research environment more closely. After completing the experiment students understand basic principles of transcription, mechanisms of inhibition, and the use of EMSAs to probe protein/DNA interactions.

Mental imagery (MI) is gaining attention as a strategy towards endogenous brain stimulation for improving motor skill. Neurofeedback (NF) is commonly used to guide MI in order to activate the relevant brain networks. The current study investigates an individualized EEG-based method for NF through broad consideration of interactions between different brain networks. We selected the change in brain functional connectivity (FC) as an objective neurophysiological measure of change in motor skill during a longitudinal physical training (PT) program. Digital tracing tasks were developed for skill training and the spatial error in tracing was used to gauge the change in skill. We used partial least squares algorithms to find the most robust contributing networks towards correlation between the resting state FC and the acquired motor skill. We used the network with the largest margin for increasing FC as the candidate for NF training while experimenting with MI during a neurofeedback training program. The participant was informed of the changes in instantaneous FC through real-time audio feedback to help guide the MI. We showed over 20% reduction in tracing error through neurofeedback training alone, without any additional PT. We also showed retention of improvement in skill for several days after the completion of neurofeedback training. Our proposed methodology shows promise for a highly individualized approach towards improvement in motor skill. Given that EEG is an accessible health and wellness technology, such a method could provide a practical complementary option towards personalized therapeutic strategies to improve motor function., IEEE Transactions on Neural Systems and Rehabilitation Engineering, 31, ISSN:1534-4320, ISSN:1558-0210

In this work, we study the influence of surface tension on light-induced wrinkling of hydrogel disks containing patterned regions of photothermally-active gold nanoparticles at the air–water interface.