Giant Terahertz Birefringence in an Ultrathin Anisotropic Semimetal.

Manipulating the polarization of light at the nanoscale is key to the development of next-generation optoelectronic devices. This is typically done via waveplates using optically anisotropic crystals, with thicknesses on the order of the wavelength. Here, using a novel ultrafast electron-beam-based technique sensitive to transient near fields at THz frequencies, we observe a giant anisotropy in the linear optical response in the semimetal WTe2 and demonstrate that one can tune the THz polarization using a 50 nm thick film, acting as a broadband wave plate with thickness 3 orders of magnitude smaller than the wavelength. The observed circular deflections of the electron beam are consistent with simulations tracking the trajectory of the electron beam in the near field of the THz pulse. This finding offers a promising approach to enable atomically thin THz polarization control using anisotropic semimetals and defines new approaches for characterizing THz near-field optical response at far-subwavelength length scales.

Relabeling for Indoor Localization Using Stationary Beacons in Nursing Care Facilities.

In this study, we propose an augmentation method for machine learning based on relabeling data in caregiving and nursing staff indoor localization with Bluetooth Low Energy (BLE) technology. Indoor localization is used to monitor staff-to-patient assistance in caregiving and to gain insights into workload management. However, improving accuracy is challenging when there is a limited amount of data available for training. In this paper, we propose a data augmentation method to reuse the Received Signal Strength (RSS) from different beacons by relabeling to the locations with less samples, resolving data imbalance. Standard deviation and Kullback-Leibler divergence between minority and majority classes are used to measure signal pattern to find matching beacons to relabel. By matching beacons between classes, two variations of relabeling are implemented, specifically full and partial matching. The performance is evaluated using the real-world dataset we collected for five days in a nursing care facility installed with 25 BLE beacons. A Random Forest model is utilized for location recognition, and performance is compared using the weighted F1-score to account for class imbalance. By increasing the beacon data with our proposed relabeling method for data augmentation, we achieve a higher minority class F1-score compared to augmentation with Random Sampling, Synthetic Minority Oversampling Technique (SMOTE) and Adaptive Synthetic Sampling (ADASYN). Our proposed method utilizes collected beacon data by leveraging majority class samples. Full matching demonstrated a 6 to 8% improvement from the original baseline overall weighted F1-score.

The topology of electronic band structures.

The study of topology as it relates to physical systems has rapidly accelerated during the past decade. Critical to the realization of new topological phases is an understanding of the materials that exhibit them and precise control of the materials chemistry. The convergence of new theoretical methods using symmetry indicators to identify topological material candidates and the synthesis of high-quality single crystals plays a key role, warranting discussion and context at an accessible level. This Perspective provides a broad introduction to topological phases, their known properties, and material realizations. We focus on recent work in topological Weyl and Dirac semimetals, with a particular emphasis on magnetic Weyl semimetals and emergent fermions in chiral crystals and their extreme responses to excitations, and we highlight areas where the field can continue to make remarkable discoveries. We further examine open questions and directions for the topological materials science community to pursue, including exploration of non-equilibrium properties of Weyl semimetals and cavity-dressed topological materials.

Relationship Between Strength and Conditioning Assessments and Rowing Performance in Female Collegiate Athletes.

ABSTRACT: Folk, AL, Garcia, CA, Whitney, SH, and Kovacs, SJ. Relationship between strength and conditioning assessments and rowing performance in female collegiate athletes. J Strength Cond Res 36(6): 1618-1621, 2022-The purpose of this study was to examine the relationship between strength and conditioning variables and rowing performance, as measured by a 2000 m ergometer time, in female collegiate rowers. Twenty-four female collegiate rowers qualified for this study by completing both types of assessments and a demographic questionnaire. Pearson correlation coefficients (r) were used to determine the association between the total 2000 m ergometer time and each strength and conditioning assessment. The assessments included a 1 repetition maximum (1RM) squat and a 1RM hang clean. After this, all significant correlations were placed in a stepwise linear regression analysis to predict the total 2000 m ergometer time. The 1RM squat and 1RM hang clean correlated with 2000 m ergometer performance (p = 0.034 and p = 0.002, respectively). Only the 1RM squat emerged as a predictor of 2000 m ergometer performance. This study highlights that the 1RM squat may be a way to predict rowing performance and build successful female collegiate rowing teams.

Axion-Field-Enabled Nonreciprocal Thermal Radiation in Weyl Semimetals.

Objects around us constantly emit and absorb thermal radiation. The emission and absorption processes are governed by two fundamental radiative properties: emissivity and absorptivity. For reciprocal systems, the emissivity and absorptivity are restricted to be equal by Kirchhoff's law of thermal radiation. This restriction limits the degree of freedom to control thermal radiation and contributes to an intrinsic loss mechanism in photonic energy harvesting systems. Existing approaches to violate Kirchhoff's law typically utilize magneto-optical effects with an external magnetic field. However, these approaches require either a strong magnetic field (∼3T) or narrow-band resonances under a moderate magnetic field (∼0.3T), because the nonreciprocity in conventional magneto-optical effects is weak in the thermal wavelength range. Here, we show that the axion electrodynamics in magnetic Weyl semimetals can be used to construct strongly nonreciprocal thermal emitters that nearly completely violate Kirchhoff's law over broad angular and frequency ranges without requiring any external magnetic field.

Reprogramming of mesenchymal stem cells by oncogenes.

Mesenchymal stem cells (MSCs) originate from embryonic mesoderm and give rise to the multiple lineages of connective tissues. Transformed MSCs develop into aggressive sarcomas, some of which are initiated by specific chromosomal translocations that generate fusion proteins with potent oncogenic properties. The sarcoma oncogenes typically prime MSCs through aberrant reprogramming. They dictate commitment to a specific lineage but prevent mature differentiation, thus locking the cells in a state of proliferative precursors. Deregulated expression of lineage-specific transcription factors and controllers of chromatin structure play a central role in MSC reprogramming and sarcoma pathogenesis. This suggests that reversing the epigenetic aberrancies created by the sarcoma oncogenes with differentiation-related reagents holds great promise as a beneficial addition to sarcoma therapies.

Innervation of dystrophic muscle after muscle stem cell therapy.

INTRODUCTION: Duchenne muscular dystrophy (DMD) is caused by loss of the structural protein, dystrophin, resulting in muscle fragility. Muscle stem cell (MuSC) transplantation is a potential therapy for DMD. It is unknown whether donor-derived muscle fibers are structurally innervated. METHODS: Green fluorescent protein (GFP)-expressing MuSCs were transplanted into the tibials anterior of adult dystrophic mdx/mTR mice. Three weeks later the neuromuscular junction was labeled by immunohistochemistry. RESULTS: The percent overlap between pre- and postsynaptic immunolabeling was greater in donor-derived GFP(+) myofibers, and fewer GFP(+) myofibers were identified as denervated compared with control GFP(-) fibers (P = 0.001 and 0.03). GFP(+) fibers also demonstrated acetylcholine receptor fragmentation and expanded endplate area, indicators of muscle reinnervation (P = 0.008 and 0.033). CONCLUSION: It is unclear whether GFP(+) fibers are a result of de novo synthesis or fusion with damaged endogenous fibers. Either way, donor-derived fibers demonstrate clear histological innervation. Muscle Nerve 54: 763-768, 2016.

Nursing home recruitment: trials, tribulations, and successes.

Many challenges are inherent when conducting research in the older adult population as well as in the nursing home environment. The safety and quality of care provided in nursing homes need further examination through research. The purpose of this paper is to discuss research issues and recruitment barriers experienced by a research team collecting data for a study assessing the education and learning needs of nursing home nurses in central Illinois and related resident outcomes. Research barriers identified in this study include organizational and administrative barriers in addition to staff barriers. The strategy that was most helpful in gaining access to nursing homes in central Illinois was face to face contact. Future nursing home researchers are encouraged to familiarize themselves with the nursing home environment, communicate with nursing home trade associations, and develop personal contacts with area nursing home administrators.

Genome-wide recruitment to Polycomb-modified chromatin and activity regulation of the synovial sarcoma oncogene SYT-SSX2.

BACKGROUND: SYT-SSX is the oncogene associated with synovial sarcoma (SS), a stem cell disease. SYT-SSX is thought to be responsible for sarcoma initiation and development. It interacts with components of Polycomb and SWI/SNF complexes, the two epigenetic controllers that maintain the heritable status of differentiation-specific genes in the stem/progenitor cell. Through these associations SYT-SSX is thought to alter gene expression programs by epigenetic mechanisms. Recently, we reported that SYT-SSX2 reprograms mesenchymal stem cells and myoblasts by dictating their commitment to the neural lineage while disrupting their normal differentiation. This reprogramming was due to the direct occupancy of proneural genes by the SYT-SSX2 nuclear complex. To gain a clear understanding of SYT-SSX2 control of gene expression networks, we conducted a thorough genome-wide analysis to determine the mechanism of its recruitment and identify signature sets of epigenetic markers that would predict its targeting and transcriptional activity. RESULTS: SYT-SSX2 was recruited to distinct loci across all chromosomes, and an overwhelming number of Polycomb-modified sites enriched with the trimethylated histone H3 on lysine 27 (H3K27me3) formed the main recruiting module for SYT-SSX2. Not all SYT-SSX2/H3K27me3-occupied genes had altered expression, denoting the requirement for additional signals upon oncogene binding. Differential binding and epigenetic patterns distinguished upregulated and downregulated genes. Most activated genes had SYT-SSX2 sites enriched with H3K27me3 within their body or near their transcription start site (TSS) whereas a majority of downregulated genes were characterized by SYT-SSX2/H3K27me3-rich regions at long-range, or by modifications associated with transcription activation within the gene body or near the TSS. Hierarchical and functional clustering identified H3K27me3 as the dominant epigenetic marker associated with SYT-SSX2 binding and gene expression. Notably, this analysis revealed a cluster of upregulated neuronal genes densely covered by H3K27me3, consistent with programming toward the neural lineage by SYT-SSX2 observed previously. CONCLUSIONS: The data analysis revealed that Polycomb complexes or their modified chromatin and their stably silenced differentiation programs seem to be the main target for SYT-SSX2, suggesting that their perturbation is at the center of tumorigenesis driven by the oncogene. Further research into this mechanism is crucial to the full understanding of SS biology.

Integrating research into a molecular cloning course to address the evolving biotechnology landscape.

The rapid development of molecular biotechnology presents a curricular challenge for educators trying to provide students with relevant coursework. A comprehensive biology education should also include opportunities for students to develop intellectual and technical skills through authentic research experiences. Integrating relevant and interesting research projects into their classes, however, can be a challenging task for instructors. To address these varied demands, we redesigned our existing molecular cloning course to incorporate an independent research project assessing calcium signaling. In the revised course, students use traditional and recombination-based cloning strategies to generate bacterial and mammalian expression vectors encoding CaMPARI, a novel fluorescent calcium indicator. Bacterially-expressed CaMPARI is used in protein quantification and purification assays. Students must also design their own research project evaluating the effect of chemotherapeutic agents on calcium signaling in a mammalian system. Revised and novel labs were designed to be modular, facilitating their integration into the course over 2 years. End-of-semester student evaluations were compared between years revealing a significant difference in students' perception of the course's difficulty between years. This change in attitude highlights potential pedagogical considerations that must be examined when introducing new material and activities into existing courses. Since calcium signaling is important for cellular process across diverse species, instructors may be able to develop research projects within their respective areas of interest. Integration of authentic research experiences into the curriculum is challenging; however, the framework described here provides a versatile structure that can be adapted to merge diverse instructor interests with evolving educational needs.

Sondheimer oscillations as a probe of non-ohmic flow in WP2 crystals.

As conductors in electronic applications shrink, microscopic conduction processes lead to strong deviations from Ohm's law. Depending on the length scales of momentum conserving (lMC) and relaxing (lMR) electron scattering, and the device size (d), current flows may shift from ohmic to ballistic to hydrodynamic regimes. So far, an in situ methodology to obtain these parameters within a micro/nanodevice is critically lacking. In this context, we exploit Sondheimer oscillations, semi-classical magnetoresistance oscillations due to helical electronic motion, as a method to obtain lMR even when lMR ≫ d. We extract lMR from the Sondheimer amplitude in WP2, at temperatures up to T ~ 40 K, a range most relevant for hydrodynamic transport phenomena. Our data on µm-sized devices are in excellent agreement with experimental reports of the bulk lMR and confirm that WP2 can be microfabricated without degradation. These results conclusively establish Sondheimer oscillations as a quantitative probe of lMR in micro-devices.

The synovial sarcoma SYT-SSX2 oncogene remodels the cytoskeleton through activation of the ephrin pathway.

Synovial sarcoma is a soft tissue cancer associated with a recurrent t(X:18) translocation that generates one of two fusion proteins, SYT-SSX1 or SYT-SSX2. In this study, we demonstrate that SYT-SSX2 is a unique oncogene. Rather than confer enhanced proliferation on its target cells, SYT-SSX2 instead causes a profound alteration of their architecture. This aberrant morphology included elongation of the cell body and formation of neurite-like extensions. We also observed that cells transduced with SYT-SSX2 often repulsed one another. Notably, cell repulsion is a known component of ephrin signaling. Further analysis of SYT-SSX2-infected cells revealed significant increases in the expression and activation of Eph/ephrin pathway components. On blockade of EphB2 signaling SYT-SSX2 infectants demonstrated significant reversion of the aberrant cytoskeletal phenotype. In addition, we discovered, in parallel, that SYT-SSX2 induced stabilization of the microtubule network accompanied by accumulation of detyrosinated Glu tubulin and nocodazole resistance. Glu tubulin regulation was independent of ephrin signaling. The clinical relevance of these studies was confirmed by abundant expression of both EphB2 and Glu tubulin in SYT-SSX2-positive synovial sarcoma tissues. These results indicate that SYT-SSX2 exerts part of its oncogenic effect by altering cytoskeletal architecture in an Eph-dependent manner and cytoskeletal stability through a concurrent and distinct pathway.

Cohesion and conflict: family influences on adolescent alcohol use in immigrant Latino families.

This study examines how cohesion and parent­child conflict relate to alcohol use among Mexican-heritage adolescents. The sample consists of 120 adolescents (14 to 18 years) participants from the Southwest sub-sample of the Latino Acculturation and Health Project. Lifetime and recent alcohol use and binge drinking were tested. Results from the logistic regressions identified high and low levels of family cohesion as a risk factor for alcohol use compared to medium levels of cohesion, and parent­child conflict predicted lifetime use and binge drinking. Low and high family cohesion levels appear to be especially problematic among Mexican adolescents who are trying to navigate two different cultural worlds. Although high family cohesion is often a characteristic of Mexican families, Mexican-heritage adolescents may view high family cohesion as a hindrance to their own independence. Unresolved conflict seems to be connected to children's problem behaviors and alcohol misuse could be utilized by adolescents as a mechanism to reduce emotional distress caused by family tensions.

Growth modelling indicates hurricanes and severe storms are linked to low coral recruitment in the Caribbean.

This study set out to test the hypothesis that hurricanes and tropical storms limit the recruitment and subsequent survival of massive non-branching corals on the barrier reef off the coast of Belize in the Gulf of Honduras. Overall, the surface areas of 523 individual coral specimens were measured, and recruitment dates were then modelled. There was no significant difference in coral cover or coral biodiversity between any of the sites studied (p > 0.1). There were significant differences in non-branching coral recruitment in years when hurricanes impacted the area (p < 0.05) compared with years when no hurricanes impacted the area. There were significantly more non-branching massive corals recruited in non-hurricane years (mean 7.7) than in hurricane years (mean 3.8; p = 0.011). When years with tropical storms are added to the years with hurricanes, there was significantly lower coral recruitment (mean 4.7) relative to non-storm or hurricane years (mean 7.4; p = 0.019). These results show that hurricanes and severe storms limited the recruitment and survival of massive non-branching corals of the Mesoamerican barrier reef and on patch reefs near the Belize coast in the Caribbean, and suggests that marine park managers may need to assist coral recruitment in years where there are hurricanes or severe storms.

A comparison of performance on the Keitel Functional Test by persons with systemic sclerosis and rheumatoid arthritis.

PURPOSE: The purpose of this study is to compare lower extremity impairments in persons with systemic sclerosis, rheumatoid arthritis, and healthy controls. METHODS: The participants were a convenience sample of 64 persons with systemic sclerosis, 58 persons with rheumatoid arthritis, and 30 healthy controls. The Keitel Functional Test was used to assess lower extremity joint motion and strength. Demographic information on age, disease duration, employment, and perceived overall health was also collected. RESULTS: Significant differences were found between the healthy control group and both the systemic sclerosis and rheumatoid arthritis groups in rising from a chair, squatting, walking 30 m, walking up and downstairs, and the total score. For hip external rotation, there were significant differences between all three groups for the right hip; for the left hip, the systemic sclerosis group had significantly less motion than the other two groups. For standing on toes, there was only a significant difference between the systemic sclerosis and the healthy control groups. CONCLUSIONS: Persons with systemic sclerosis and rheumatoid arthritis have similar levels of lower extremity impairments but greater impairments compared to the healthy controls. These impairments may lead to decreased mobility paired with difficulties with activities of daily living such as lower extremity dressing, bathing, and feet care. Implications for Rehabilitation Persons with systemic sclerosis and rheumatoid arthritis have similar levels of lower extremity impairments but greater impairments compared to the healthy controls. Findings from this study indicate a need for rehabilitation for persons with systemic sclerosis and rheumatoid arthritis as the lower extremity impairments may lead to decreased mobility paired with difficulties with daily living activities such as lower extremity dressing, bathing, and feet care. The Keitel Functional Test could be used as a quick screening test for lower extremity impairments.

CE: Original Research: Understanding the Hospital Experience of Older Adults with Hearing Impairment.

: Background: Older hospitalized adults with hearing impairment are vulnerable to adverse outcomes. These patients are at risk for being labeled confused, experiencing a loss of control, experiencing heightened fear and anxiety, and misunderstanding the plan of care. OBJECTIVE: This qualitative study sought to assess the hospital experience of older adults with hearing impairment in order to formulate suggestions for improving nursing care. METHODS: Open-ended interviews were conducted with eight participants, ages 70 to 95 years, who were identified as having a hearing impairment and were admitted as inpatients to a midwestern medical center. RESULTS: Through data analysis, three common themes emerged: health care communication difficulties, passivity and vulnerability, and frustration with family. CONCLUSIONS: Nurses will benefit from having a deeper understanding of the hospital experience of this vulnerable population. Efforts to address their needs can be accomplished through the following nursing actions: assess, accommodate, educate, empower, and advocate.