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Previous research has established that juveniles who experience negative parental influence are more likely to engage in problem and offending behavior. Less attention has been given to the possibility that criminal thinking styles might partially explain this relationship. This study examined the negative parental influences and criminal thinking styles of 1,354 juvenile offenders to establish that both negative parental influences and criminal thinking are significantly associated with juvenile problem and offending behavior. Further, the analysis showed that juvenile criminal thinking (proactive, reactive, and general) might mediate the relationship between negative parental influences and problem behavior. Implications for such findings are discussed.

Datasets of offender attributes, both pre-custody and in-custody, were provided by the Correctional Service of Canada with the goal of exploring whether Security Threat Group (STG) offenders (informally, gang members of various kinds) differ in any systematic way from other offenders. For pre-custody attributes, we show that the entire offender population varies along two almost independent axes, one associated with affinity for violence, and the other with affinity for substance abuse. Within this structure, STG offenders are characteristically less extreme, in either direction, than the general offender population. For approximately two dozen attributes, STG offenders, as a group, tend to have higher values; for a few, they tend to have lower values. For in-custody attributes, the entire offender population forms a triangular structure whose vertices represent: passivity; violence and troublemaking; and involvement in programs leading to partial release. The differences between the STG offender population and the general offender population are small. An offender who is placed at the high end of the propensity for violence axis and/or the high end of the substance abuse axis based on pre-custody attributes is much more likely to be involved in incidents, grievances, and violence while in custody. This may have implications for risk stratification of incoming offenders.

Since the 1950s, considerable circumstantial evidence had been presented that endogenous 5-HT (serotonin) synthesized from within the wall of the gastrointestinal (GI) tract played an important role in GI motility and transit. However, identifying the precise functional role of gut-derived 5-HT has been difficult to ascertain, for a number of reasons. Over the past decade, as recording techniques have advanced significantly and access to new genetically modified animals improved, there have been major new insights and major changes in our understanding of the functional role of endogenous 5-HT in the GI tract. Data from many different laboratories have shown that major patterns of GI motility and transit still occur with minor or no, change when all endogenous 5-HT is pharmacologically or genetically ablated from the gut. Furthermore, antagonists of 5-HT₃ receptors are equally, or more potent at inhibiting GI motility in segments of intestine that are completely depleted of endogenous 5-HT. Here, the most recent findings are discussed with regard to the functional role of endogenous 5-HT in enterochromaffin cells and enteric neurons in gut motility and more broadly in some major homeostatic pathways.

Introduction: This study investigates whether student confidence could be improved through the use of simulated patient case-based scenarios.

Materials and methods: Students in their 4th and 5th year of undergraduate study completed an online e-portfolio workbook consisting of activities related to five simulated patient cases. Following completion of the relevant learning activities within the e-portfolio, students then viewed a tutor case presentation video and attended simulated clinic sessions to complete corresponding exercises involving 3D-printed teeth related to the case. Subsequently, students undertook online self-reflection and goal-setting activities to aid their development. An anonymous questionnaire was distributed to all participants to gain insight into the themes of student confidence and learning support. The Cronbach's Alpha coefficient was calculated for both sections of the student questionnaire. The values for "student confidence" and "learning support" were α = 0.91 and α = 0.87, respectively.

Results: There was a total of 89 valid student responses to the questionnaire (65%). A Spearman's correlation of r_s = 0.50 (p < .001) suggests a tentative causative correlation between the learning support offered through the simulated patient cases and student confidence. There was a positive directional relationship between engagement with the learning support of the simulated patient cases and student confidence scores.

Conclusion: Student confidence increased following the completion of simulated patient cases and students found the learning support offered beneficial to their development. This learning intervention has the potential to improve student self-efficacy, develop contextual competency and facilitate reflective practice. Simulated patient cases may be a useful precursor or adjunct to traditional patient clinics.

Coral reefs are hotspots of marine biodiversity, which results in the synthesis of a wide variety of compounds with unique molecular scaffolds, and bioactivities, rendering reefs an ecosystem of interest. The chemodiversity stems from the intricate relationships between inhabitants of the reef, as the chemistry produced partakes in intra- and interspecies communication, settlement, nutrient acquisition, and defense. However, the coral reefs are declining at an unprecedented rate due to climate change, pollution, and increased incidence of pathogenic diseases. Among pathogens, Vibrio spp. bacteria are key players resulting in high mortality. Thus, alternative strategies such as application of beneficial bacteria isolated from disease-resilient species are being explored to lower the burden of pathogenic species. Here, we apply coculturing of a coral-derived pathogenic species of Vibrio and beneficial bacteria and leverage recent advancements in untargeted metabolomics to discover engineerable beneficial traits. By chasing chemical change in coculture, we report Microbulbifer spp.-mediated degradation of amphibactins, produced by Vibrio spp. bacteria to sequester iron. Additional biochemical experiments revealed that the degradation occurs in the peptide backbone and requires the enzyme fraction of Microbulbifer. A reduction in iron affinity is expected due to the loss of one Fe(III) binding moiety. Therefore, we hypothesize that this degradation shapes community behaviors as it pertains to iron acquisition, a limiting nutrient in the marine environment, and survival. Furthermore, Vibrio sp. bacteria suppressed natural product synthesis by beneficial bacteria. Understanding biochemical mechanisms behind these interactions will enable engineering probiotic bacteria capable of lowering pathogenic burdens during heat waves and incidence of disease.

Novichok nerve agents, such as A-230, A-232, and A-234, were classified as Schedule 1 chemicals under the Chemical Weapons Convention (CWC) by the Organisation for the Prohibition of Chemical Weapons (OPCW) following poisoning incidents in 2018. As a result, the production, storage, and use of these chemicals are strictly prohibited by CWC signatory nations. The identification of biomarkers indicating Novichok exposure in humans is crucial for prompt detection and response to potential incidents involving these banned chemical weapons. In this study, BChE was isolated from human serum samples exposed to Novichok nerve agents in vitro using immunomagnetic capture, followed by enzymatic digestion with Pronase or proteinase K to generate new peptide biomarkers indicative of exposure. We identified nine previously unpublished Novichok-adducted peptides generated through enzymatic digestion with proteinase K and Pronase using liquid chromatography-high-resolution mass spectrometry. Two peptides, [Agent]-serine-alanine for proteinase K digestion and [Agent]-serine-alanine-glycine for Pronase digestion, were selected for optimization due to their abundance. The analysis was subsequently transferred to an LC-triple quadrupole system to enhance throughput and detect these new biomarkers at the limits of detection corresponding to BChE inhibition levels of 3.90% or less. These additional biomarkers can improve laboratory preparedness for OPCW-designated biomedical testing laboratories as well as other clinical and investigative laboratories tasked with responding to emergencies involving these highly toxic chemicals.

The rise of resistance to antiretroviral drugs due to mutations in human immunodeficiency virus-1 (HIV-1) protease is a major obstacle to effective treatment. These mutations alter the drug-binding pocket of the protease and reduce the drug efficacy by disrupting interactions with inhibitors. Traditional methods, such as biochemical assays and structural biology, are crucial for studying enzyme function but are time-consuming and labor-intensive. To address these challenges, we developed HIV OctaScanner, a machine learning algorithm that predicts the proteolytic cleavage activity of octameric substrates at the HIV-1 protease cleavage sites. The algorithm uses a Random Forest (RF) classifier and achieves a prediction accuracy of 89% in the identification of cleavable octamers. This innovative approach facilitates the rapid screening of potential substrates for HIV-1 protease, providing critical insights into enzyme function and guiding the development of more effective therapeutic strategies. By improving the accuracy of substrate identification, HIV OctaScanner has the potential to support the development of next generation antiretroviral treatments.

The light-harvesting complex II (LHCII) in green plants exhibits highly efficient excitation energy transfer (EET). A comprehensive understanding of the EET mechanism in LHCII requires quantum chemical, molecular dynamics (MD), and statistical mechanics calculations that can adequately describe pigment molecules in heterogeneous environments. Herein, we develop MD simulation parameters that accurately reproduce the quantum mechanical/molecular mechanical energies of both the ground and excited states of all chlorophyll (Chl) molecules in membrane embedded LHCII. The present simulations reveal that Chl a molecules reside in more inhomogeneous environments than Chl b molecules. We also find a narrow gap between the exciton energy levels of Chl a and Chl b. In addition, we investigate the nature of the exciton states of Chl molecules, such as delocalization, and analyze the optical spectra of LHCII, which align with experimental results. Thus, the MD simulation parameters developed in this study successfully reproduce the excitonic and optical properties of the Chl molecules in LHCII, validating their effectiveness.

Classical reaction barriers in density-functional theory are considered from the perspective of the density-fixed adiabatic connection. A 'reaction adiabatic-connection integrand', $R_{\lambda }$, is introduced, where λ is the electron-electron interaction strength, for which ${\int }_0^1{R}_{\lambda }d\lambda$ equals the barrier, meaning the barrier can be easily visualized as the area under a plot of $R_{\lambda }$ vs λ. For five chemical reactions, plots of reference $R_{\lambda }$, calculated from Lieb maximizations at the coupled-cluster level of theory, are compared with approximate $R_{\lambda }$, calculated from common exchange-correlation functionals using coordinate scaling, for coupled-cluster densities. The comparison provides a simple way to visualize and understand functional-driven errors and trends in barriers from approximate functionals, while allowing a clean separation of the role of exchange and correlation contributions to the barrier. Specifically, the accuracy of $R_0$ is determined entirely by the accuracy of the exchange functional, while the shape of $R_{\lambda }$ is determined entirely by the correlation functional. The results clearly illustrate why the optimal amount of exact (orbital) exchange in hybrid functionals differs between reactions, including forward and reverse directions in the same reaction, and hence why simply introducing larger amounts of exact exchange may not be a reliable approach for improving barriers. Instead, the shape of $R_{\lambda }$ must be captured more accurately through more accurate correlation functionals, and the numerical data presented may be useful for this purpose. Density-driven errors are then considered, and possible cancellation with functional-driven errors in barriers─noted in prior studies when Hartree-Fock densities are used─is illustrated from the perspective of $R_{\lambda }$.

We present an application of our new theoretical formulation of quantum dynamics, moment propagation theory (MPT) (Boyer et al., J. Chem. Phys. 160, 064113 (2024)), for employing machine-learning techniques to simulate the quantum dynamics of electrons. In particular, we use real-time time-dependent density functional theory (RT-TDDFT) simulation in the gauge of the maximally localized Wannier functions (MLWFs) for training the MPT equation of motion. Spatially localized time-dependent MLWFs provide a concise representation that is particularly convenient for the MPT expressed in terms of increasing orders of moments. The equation of motion for these moments can be integrated in time, while the analytical expressions are quite involved. In this work, machine-learning techniques were used to train the second-order time derivatives of the moments using first-principles data from the RT-TDDFT simulation, and this MPT enabled us to perform electron dynamics efficiently. The application to computing optical absorption spectrum for various systems was demonstrated as a proof-of-principles example of this approach. In addition to isolated molecules (water, benzene, and ethene), condensed matter systems (liquid water and crystalline silicon) were studied, and we also explored how the principle of the nearsightedness of electrons can be employed in this context.