Showing papers by "University of Memphis published in 2022"

Breaking through the dynamic strength-ductility trade-off in TiB reinforced Ti composites by incorporation of graphene nanoplatelets

Abstract: Insight into the dynamic mechanical behavior of titanium matrix composites (TiMCs) under the extreme condition is requisite to provide improved understanding for the development of new protective materials. Here we reported a strategy to overcome the strength-ductility incompatibility in TiB whiskers reinforced titanium (TiBw/Ti) composites through tailoring a novel three-dimensional (3D) reinforcement configuration via the incorporation of graphene nanoplatelets (GNPs). Effects of GNPs addition on the spatial distribution of TiBw, interface microstructure and mechanical properties were investigated. Results evidenced that TiBw-(GNPs)/Ti composites showed concurrently enhanced dynamic strength and plasticity as compared to the conventional TiBw/Ti. The improved dynamic strength of TiBw-(GNPs)/Ti were derived from the alignment of 3D reinforcements, texture strengthening and GNPs-TiC synergistic effects. Stop-ring technology was introduced as the post-deformation analysis method. It turned out that the incorporation of GNPs induced higher thermal conductivity and strain-hardening capability, which delayed the formation of adiabatic shear bands. Moreover, considerable energy dissipation was required due to GNPs impeded the cracks propagation, which led to the improved dynamic plasticity.

Including Homeless Populations in Disaster Preparedness, Planning, and Response: A Toolkit for Practitioners.

Abstract: CONTEXT People experiencing homelessness are often the first and most severely affected group during disasters. Nonetheless, communities across the United States have frequently failed to adequately address the needs of homeless populations in disaster planning, response, and recovery. Communities must build multisector collaborative relationships and ensure that homeless service providers are adequately resourced. However, constraints in funding and staffing, combined with a lack of guidance about how to achieve an integrated approach to disaster planning for people experiencing homelessness, have hindered communities' ability to accomplish these goals. PROGRAM The US Department of Veterans Affairs, the US Department of Health and Human Services, and the US Department of Housing and Urban Development created an interagency workgroup to identify resources to help communities address the disaster needs of homeless populations. This workgroup created a toolkit to address this gap: Disaster Preparedness to Promote Community Resilience.This article describes the development of the toolkit. The toolkit is divided into 3 sections:Section 1 provides guidance to homeless service providers and government entities in identifying collaborative relationships to ensure that services are available to address homeless populations' disaster needs. Section 2 offers nonprofit homeless service providers guidance in creating their disaster response plans. Section 3 aims to ensure that public health officials and health care systems have the capacity to provide health care to homeless populations during disasters. IMPLEMENTATION Efforts are under way to develop a disaster preparedness training manual to assist nonprofit homeless service organizations. DISCUSSION Homeless service providers are vital partners in disaster response. Integrating them into emergency management and ensuring that they are adequately prepared for disasters will effectively enable them to contribute their unique skill sets to community disaster recovery.

Aspirin ameliorates the cognition impairment in mice following benzo[a]pyrene treatment via down-regulating BDNF IV methylation

Abstract: Benzo[a]pyrene (B[a]P) is neurotoxic, however, the mechanisms remain unclear and there is no effective prevention. Available evidence suggests a role of DNA methylation in B[a]P-induced neurotoxicity. This study investigated the brain-derived neurotrophic factor (BDNF) IV methylation in the development of and aspirin intervention against B[a]P's neurotoxicity in mice and HT22 cells. Mice were intraperitoneally treated with solvent or B[a]P (0.5, 2, and 10 mg/kg b.w.) for 60 days. An intervention group was treated simultaneously with B[a]P (10 mg/kg, i.p.) and aspirin (10 mg/kg, daily water-drinking). The treated mice showed a dose-dependent cognitive and behavioral impairment, and cerebral cell apoptosis, which were alleviated by aspirin co-treatment. Following B[a]P treatment, DNA methyltransferase (DNMTs) and BDNF IV hypermethylation were increased in the cerebral cortex of mice compared to controls, while significant decreases were found in BDNF IV and BDNF mRNA, and BDNF protein levels. Aspirin co-treatment rescued DNMTs activation and BDNF IV hypermethylation, and mitigated the recession in BDNF mRNA and protein induced by B[a]P treatment. Similar results were shown in HT22 cells. These findings reveal a critical role of BDNF IV methylation in the neurotoxicity of B[a]P, and demonstrate a promising prevention of aspirin against B[a]P-induced cognitive impairment via inhibiting BDNF IV hypermethylation.

Quantifying the consumer’s dependence on different information sources on acceptance of autonomous vehicles

Abstract: • Explores the importance of multiple sources for pre-purchase information of CAVs among Tennessee residents. • Utilizes latent segmentation to identify public’s scepticism of CAVs. • Indifferent individuals: stronger reliance on information sources than skeptical individuals. • Residents interested in owning a CAV rely on their peers for the information. • Residents interested in autonomous public transit rely on the advertisements for the information. Recent academic research and industrial commitments highlight the potential of connected and autonomous vehicles (CAVs) in transforming the way we travel. However, there are some anticipated barriers associated with the widespread consumer adoption of CAVs, including but not limited to low user acceptance, cybersecurity, safety, and legislation. The existing literature is non-existent in capturing the impact of information received from multiple sources (peers, car dealers, media advertisements, and personal research) on the consumers’ acceptance of CAVs while considering these barriers associated with CAV. In this direction, we quantify the impact of the multiple information sources on the individuals concerned and indifferent about the anticipated barriers of CAVs to boost their acceptance while utilizing a two-step econometric framework based on an online survey of 4,448 Tennesseans. The two-step modeling framework utilizes latent class analysis followed by a multivariate ordered logit model. Results indicated that the elderly, three or more person households, and residents interested in owning a CAV are more likely to be concerned about CAV barriers. In contrast, males, physically challenged, and residents willing to pay higher for CAV are more likely to be indifferent toward CAV barriers. Among concerned individuals, the elderly, females, and residents willing to pay more than $30 k for a conventional car are more likely to rely on car dealers when purchasing a CAV. The results of this study are expected to assist automakers, technology companies, policymakers, and third-party agencies to advertise, promote and introduce CAVs effectively through appropriate information channel(s) to boost their consumer acceptance.

Finding Effective and Efficient Ways to Integrate Research Advances Into the Clinical Suicide Risk Assessment Interview

Abstract: Research in clinical suicidology continues to rapidly expand, much of it with implications for day-to-day clinical practice. Clinicians routinely wrestle with how best to integrate recent advances into practice and how to do so in efficient and effective fashion. This article identifies five critical domains of recent research findings and offers examples of simple questions that can easily be integrated into a clinician's existing suicide risk assessment interview and related protocol helping inform the risk formulation process.

SATB2: A versatile transcriptional regulator of craniofacial and skeleton development, neurogenesis and tumorigenesis, and its applications in regenerative medicine

Abstract: SATB2 (special AT-rich sequence-binding protein 2) is a member of the special AT-rich binding protein family. As a transcription regulator, SATB2 mainly integrates higher-order chromatin organization. SATB2 expression appears to be tissue- and stage-specific, and is governed by several cellular signaling molecules and mediators. Expressed in branchial arches and osteoblast-lineage cells, SATB2 plays a significant role in craniofacial pattern and skeleton development. In addition to regulating osteogenic differentiation, SATB2 also displays versatile functions in neural development and cancer progression. As an osteoinductive factor, SATB2 holds great promise in improving bone regeneration toward bone defect repair. In this review, we have summarized our current understanding of the physiological and pathological functions of SATB2 in craniofacial and skeleton development, neurogenesis, tumorigenesis and regenerative medicine.

Periodic Nanohole Arrays with Enhanced Lasing and Spontaneous Emissions for Low-Cost Plasmonic Devices

Abstract: Periodic arrays of air nanoholes in thin metal films that support surface plasmon resonances can provide an alternative approach for boosting the light–matter interactions at the nanoscale. Nanohole arrays have garnered great interest in recent years for their use in biosensing, light emission enhancement, and spectroscopy. Here, we employ a simple technique to fabricate nanohole arrays and examine their photonic applications including enhanced lasing and spontaneous emission of novel nanomaterials. In contrast to the complicated and most commonly used electron-beam lithography technique, hexagonal arrays of nanoholes are fabricated by using a simple combination of shadowing nanosphere lithography technique and electron-beam deposition. Through spectral and temporal characterizations, it was shown that these arrays offer an enhancement in the lasing emission of an organic dye liquid gain medium with a quality factor above 150 as well as an accelerated decay rate for CdSe quantum dots. The simple fabrication of nanohole arrays together with their excellent optical responses can therefore offer a great potential in the industrialization of plasmonic devices for use in various realms of emerging technologies such as gas sensing, biomedical imaging, and ultrafast on-chip coherent light sources.

Experiencing Shame: How Does Gender Affect the Interpersonal Dynamics of Restorative Justice?:

Abstract: Although reintegrative shaming theory suggests that, in comparison to males, females are more interdependent and thus susceptible to reintegrative rather than disintegrative shaming, it is unclear ...

Association of the modified creatinine index with muscle strength and mortality in patients undergoing hemodialysis

Abstract: In the updated consensus, low muscle strength overtook the role of low muscle mass, and probable sarcopenia was diagnosed once low muscle strength was detected. Whether the modified creatinine index (mCI) could identify persons with probable sarcopenia who may be at risk of adverse outcomes remains unknown. We aimed to evaluate the association of the mCI with probable sarcopenia and mortality in patients undergoing hemodialysis.In the cross-sectional study (n = 346), univariate and multivariable logistic regression analyses were performed to study the association of mCI with probable sarcopenia. Modified Quantitative Subjective Global Assessment (MQSGA) was used to evaluate the nutritional status. The performance of the mCI value for identifying probable sarcopenia was analyzed using receiver operating characteristic (ROC) curve analysis. The appropriate cutoff points were determined using Youden's method. In the longitudinal cohort study composed of an independent hemodialysis cohort (n = 218), cox proportional regression models were used to evaluate crude and adjusted hazard ratios and 95% confidence intervals (CIs) of death by mCI and MQSGA.Cross-sectional results showed that after adjusting for confounders, the association of mCI with low muscle strength remained significant. The area under the curve (AUC) of the mCI to predict probable sarcopenia was 0.804 (95% CI, 0.744-0.863; p < 0.001) for men and 0.787 (95% CI, 0.711-0.864; p < 0.001) for women. The optimal mCI cutoff values were 21.07 mg/kg/d for men and 19.57 mg/kg/d for women, respectively. Longitudinal results showed that compared with those in the high mCI group, subjects in the low mCI group had a higher risk of death for all causes (adjusted HR, 2.51; 95% CI, 1.16-5.41; p = 0.019). Adding the mCI significantly improved the predictive accuracy for death with an increase in C-index from 0.785 to 0.805 (p = 0.026) and improved the net reclassification index (38.6%, p = 0.021), while adding MQSGA did not.The mCI is a predictor of muscle strength and survival in hemodialysis patients, and is preferable to the MQSGA for predicting death. Assessment of mCI could provide additional predictive and prognostic information to sarcopenia.

Nonlocal and local transports in a silicene-based superconducting double-barrier tunnel junction with two ferromagnetic electrodes

Abstract: We investigate theoretically the nonlocal and local transport properties of relativistic electrons tunnelling through a silicene-based superconducting double-barrier sandwiched between two ferromagnets in the presence of an external electric field. Based on the Blonder-Tinkham-Klapwijk formalism, the crossed Andreev reflection (CAR), nonlocal, and local differential conductances are numerically calculated by using a transfer-matrix method. We find that the energy regions of both the exclusive elastic cotunneling and exclusive CAR processes are gradually broadened as the exchange splitting energy increases. The CAR, nonlocal, and local differential conductances have a symmetrical distribution with respect to the external electric field and the nonlocal transport process is suppressed when the superconducting gap is large enough. Furthermore, the CAR, nonlocal, and local differential conductances exhibit periodic oscillatory behavior by increasing either the superconducting or insulating barrier potential, along with typical quasiperiodic oscillations as the middle insulating barrier width increases.

Market fairness and efficiency: Evidence from the Tokyo Stock Exchange*

Abstract: In 2015 the Tokyo Stock Exchange (TSE) implemented Arrowhead Renewal improvements (ARI) that reduced latency from about one millisecond to less than 0.5 ms. Simultaneously, the ARI introduced new risk management functions to improve market fairness by reducing manipulative trading strategies. We find a dramatic improvement in market fairness as proxied by marking-the-close incidents, which declined by 61.19%. We find a much smaller improvement in market efficiency. Specifically, there was a reduction in the effective (quoted) spread of 6.45% (5.79%). The most dramatic improvement in market quality (fairness and efficiency) was for low-tick-size and high-market-capitalization stocks.