Search

In teacher professional development (PD), grouping teachers with varying levels of experience can be a productive and empowering way to stimulate the exchange and co-generation of content and pedagogical knowledge. However, less experienced teachers can face socio-emotional risks when engaging in collaborative science content reasoning tasks with more experienced colleagues, and these risks may impact the collaborative experience of both parties and the learning environment in teacher PD. This exploratory case study examines the process of productively navigating socio-emotional risks and interpersonal tensions encountered by a veteran and pre-service physics teacher during one episode of discussing physics content. We use a single term, "comfort-building," to encapsulate discursive moves that result in increased feelings of comfort and safety by the participants. Comfort-building includes moves that serve to mitigate social risk, ease tension, and avoid discomfort, as well as those geared toward finding common ground and co-navigating challenges. These moves can carve out conversational space for teachers to more confidently face risks associated with being accountable to the physics content knowledge and engage in discipline-based conversations more deeply. The presented case was followed by video-stimulated individual interviews to determine how consciously the teachers connected their participation to explicit risk and comfort. This case study highlights an affective dimension for consideration in the continued study and facilitation of science teacher PD, especially programs that bring together teachers with a variety of backgrounds and skill sets.

We study the effect of strain on the magnetic properties and magnetization configurations in nanogranular FexGe1-x films (x = 0.53 ±0.05) with and without B20 FeGe nanocrystals surrounded by an amorphous structure. Relaxed films on amorphous silicon nitride membranes reveal a disordered skyrmion phase while films near and on top of a rigid substrate favor ferromagnetism and an anisotropic hybridization of Fe d levels and spin-polarized Ge sp band states. The weakly coupled topological states emerge at room temperature and become more abundant at cryogenic temperatures without showing indications of pinning at defects or confinement to individual grains. These results demonstrate the possibility to control magnetic exchange and topological magnetism by strain and inform magnetoelasticity-mediated voltage control of topological phases in amorphous quantum materials.

Manipulating physical properties through ion migration in complex oxide thin films is an emerging research direction to achieve tunable materials for advanced applications. While the reduction of complex oxides has been widely reported, few reports exist on the modulation of physical properties through a direct hydrogenation process. Here, we report an unusual mechanism for hydrogen-induced topotactic phase transitions in perovskite La0.7Sr0.3CoO3 thin films. Hydrogenation is performed upon annealing in a pure hydrogen gas environment, offering a direct understanding of the role that hydrogen plays at the atomic scale in these transitions. Topotactic phase transformations from the perovskite (P) to hydrogenated-brownmillerite (H-BM) phase can be induced at temperatures as low as 220 °C, while at higher hydrogenation temperatures (320-400 °C), the progression toward more reduced phases is hindered. Density functional theory calculations suggest that hydroxyl bonds are formed with the introduction of hydrogen ions, which lower the formation energy of oxygen vacancies of the neighboring oxygen, enabling the transition from the P to H-BM phase at low temperatures. Furthermore, the impact on the magnetic and electronic properties of the hydrogenation temperature is investigated. Our research provides a potential pathway for utilizing hydrogen as a basis for low-temperature modulation of complex oxide thin films, with potential applications in neuromorphic computing.

Antiferromagnetic (AFM) spintronics offer several benefits compared to their ferromagnetic (FM) counterparts, such as high storage capacity and faster processing speed, however, difficulties in manipulating and detecting the AFM moments impede their implementation. Spin-flop coupling, the interfacial perpendicular coupling between FM and AFM moments, can be utilized to control the orientation of AFM moments with the application of moderate magnetic fields on the scale of tenths of a Tesla. In this work, epitaxial bilayers of AFM La0.5Sr0.5FeO3 (LSFO)/FM La0.7Sr0.3MnO3 (LSMO) with fixed LSMO thickness (∼85 u.c.) and LSFO thicknesses varying from 10 to 50 u.c. were investigated to determine the effect of Sr doping and La1-xSrxFeO3 magnetocrystalline anisotropy on the strength of spin-flop coupling. X-ray magnetic linear dichroism demonstrated that the spin-flop coupling strength decreased with increasing LSFO layer thickness, persisting at a thickness of 50 u.c. (∼20 nm). Furthermore, photoemission electron microscopy revealed a domain-by-domain correlation between the FM and AFM domains consistent with the perpendicular orientation dictated by spin-flop coupling. These results demonstrate that LSFO/LSMO bilayers have the potential to serve as a model materials system for AFM spin transport measurements.

A magnon is a collective excitation of the spin structure in a magnetic insulator and can transmit spin angular momentum with negligible dissipation. This quantum of a spin wave has always been manipulated through magnetic dipoles (that is, by breaking time-reversal symmetry). Here we report the experimental observation of chiral spin transport in multiferroic BiFeO3 and its control by reversing the ferroelectric polarization (that is, by breaking spatial inversion symmetry). The ferroelectrically controlled magnons show up to 18% modulation at room temperature. The spin torque that the magnons in BiFeO3 carry can be used to efficiently switch the magnetization of adjacent magnets, with a spin-torque efficiency comparable to the spin Hall effect in heavy metals. Utilizing such controllable magnon generation and transmission in BiFeO3, an all-oxide, energy-scalable logic is demonstrated composed of spin-orbit injection, detection and magnetoelectric control. Our observations open a new chapter of multiferroic magnons and pave another path towards low-dissipation nanoelectronics.

Cytokine release syndrome (CRS) is a frequently observed side effect of chimeric antigen receptor (CAR)-T cell therapy. Here, we report self-regulating T cells that reduce CRS severity by secreting inhibitors of cytokines associated with CRS. With a humanized NSG-SGM3 mouse model, we show reduced CRS-related toxicity in mice treated with CAR-T cells secreting tocilizumab-derived single-chain variable fragment (Toci), yielding a safety profile superior to that of single-dose systemic tocilizumab administration. Unexpectedly, Toci-secreting CD19 CAR-T cells exhibit superior in vivo antitumor efficacy compared with conventional CD19 CAR-T cells. scRNA-seq analysis of immune cells recovered from tumor-bearing humanized mice revealed treatment with Toci-secreting CD19 CAR-T cells enriches for cytotoxic T cells while retaining memory T-cell phenotype, suggesting Toci secretion not only reduces toxicity but also significantly alters the overall T-cell composition. This approach of engineering T cells to self-regulate inflammatory cytokine production is a clinically compatible strategy with the potential to simultaneously enhance safety and efficacy of CAR-T cell therapy for cancer.

Nickel-platinum-based synthetic ferrimagnets (SFi's) are highly tunable and rare-earth-free materials that allow ultrafast all optical control of magnetism to be explored. This study considers a SFi composed of a ferromagnetic [Ni/Pt] multilayer and a ferromagnetic Co layer, separated by an Ir layer that mediates an antiferromagnetic coupling. Helicity-independent all optical switching (HI-AOS) between two antiparallel magnetization states is observed. AOS may be realized at increased temperature through reduction of the thickness of the Pt layers. Switching is unidirectional and has a strong dependence on the applied magnetic field history, which suggests the possible presence of a nanoscale magnetic texture that may be important in controlling AOS in SFi systems.

Successful acclimation to copper (Cu) deficiency involves a fine balance between Cu import and export. In the green alga Chlamydomonas reinhardtii, Cu import is dependent on a transcription factor, Copper Response Regulator 1 (CRR1), responsible for activating genes in Cu-deficient cells. Among CRR1 target genes are two Cu transporters belonging to the CTR/COPT gene family (CTR1 and CTR2) and a related soluble protein (CTR3). The ancestor of these green algal proteins was likely acquired from an ancient chytrid and contained conserved cysteine-rich domains (named the CTR-associated domains, CTRA) that are predicted to be involved in Cu acquisition. We show by reverse genetics that Chlamydomonas CTR1 and CTR2 are canonical Cu importers albeit with distinct affinities, while loss of CTR3 did not result in an observable phenotype under the conditions tested. Mutation of CTR1, but not CTR2, recapitulates the poor growth of crr1 in Cu-deficient medium, consistent with a dominant role for CTR1 in high-affinity Cu(I) uptake. On the other hand, the overaccumulation of Cu(I) (20 times the quota) in zinc (Zn) deficiency depends on CRR1 and both CTR1 and CTR2. CRR1-dependent activation of CTR gene expression needed for Cu over-accumulation can be bypassed by the provision of excess Cu in the growth medium. Over-accumulated Cu is sequestered into the acidocalcisome but can become remobilized by restoring Zn nutrition. This mobilization is also CRR1-dependent, and requires activation of CTR2 expression, again distinguishing CTR2 from CTR1 and consistent with the lower substrate affinity of CTR2.One sentence summaryRegulation of Cu uptake and sequestration by members of the CTR family of proteins in Chlamydomonas.

Diet is inextricably linked to human health and biological functionality. Reduced cognitive function among other health issues has been correlated with a western diet (WD) in mouse models, indicating that increases in neurodegeneration could be fueled in part by a poor diet. In this study, we use matrix-assisted laser desorption/ionization mass spectrometry imaging (MALDI MSI) to spatially map the lipidomic profiles of male and female mice that were fed a high-fat, high-sucrose WD for a period of 7 weeks. Our findings concluded that the cortex and corpus callosum showed significant lipid variation by WD in female mice, while there was little to no variation in the hippocampus, regardless of sex. On the other hand, lipid profiles were significantly affected by sex in all regions. Overall, 83 lipids were putatively identified in the mouse brain; among them, HexCer(40:1;O3) and PE(34:0) were found to have the largest statistical difference based on diet for female mice in the cortex and corpus callosum, respectively. Additional lipid changes are noted and can serve as a metric for understanding the brain's metabolomic response to changes in diet, particularly as it relates to disease.

BACKGROUND: Dolutegravir (DTG) is a cornerstone of global antiretroviral (ARV) therapy (ART) due to its high efficacy and favorable tolerability. However, limited data exist regarding the risk of emergent integrase strand transfer inhibitor (INSTI) drug-resistance mutations (DRMs) in individuals receiving DTG-containing ART. METHODS: We performed a PubMed search using the term Dolutegravir, last updated 18 December 2023, to estimate the prevalence of VF with emergent INSTI DRMs in people living with HIV (PLWH) without previous VF on an INSTI who received DTG-containing ART. RESULTS: Of 2131 retrieved records, 43 clinical trials, 39 cohorts, and 6 cross-sectional studies provided data across 6 clinical scenarios based on ART history, virological status, and co-administered ARVs: (1) ART-naïve PLWH receiving DTG plus two NRTIs; (2) ART-naïve PLWH receiving DTG plus lamivudine; (3) ART-experienced PLWH with VF on a previous regimen receiving DTG plus two NRTIs; (4) ART-experienced PLWH with virological suppression receiving DTG plus two NRTIs; (5) ART-experienced PLWH with virological suppression receiving DTG and a second ARV; and (6) ART-experienced PLWH with virological suppression receiving DTG monotherapy. The median proportion of PLWH in clinical trials with emergent INSTI DRMs was 1.5% for scenario 3 and 3.4% for scenario 6. In the remaining four trial scenarios, VF prevalence with emergent INSTI DRMs was ≤0.1%. Data from cohort studies minimally influenced prevalence estimates from clinical trials, whereas cross-sectional studies yielded prevalence data lacking denominator details. CONCLUSIONS: In clinical trials, the prevalence of VF with emergent INSTI DRMs in PLWH receiving DTG-containing regimens has been low. Novel approaches are required to assess VF prevalence with emergent INSTI DRMs in PLWH receiving DTG in real-world settings.

A 78-year-old woman with an ocular history of cataract surgery with a diffractive intraocular lens (IOL) in each eye has developed fluctuating vision, greater in the right eye than the left eye, after 4 years. She has a history of inactive central serous retinopathy and a vision potential of 20/25 + 2 in the right eye and 20/25 in the left eye. She has well-controlled diabetes, hypertension, and hypercholesterolemia. She has enjoyed her spectacle independence for some time and wishes to have her vision restored. On examination, her uncorrected distance visual acuity (UDVA) was 20/50 in the right eye and 20/25 in the left eye and her uncorrected near visual acuity (UNVA) was J3 in the right eye and J1 in the left eye. Intraocular pressures (IOPs) measured 22 mm Hg in the right eye and 18 mm Hg in the left eye. Pupils had limited reactivity with irregularity in the right eye but no obvious relative afferent pupillary defect. Motility and confrontation visual fields were unremarkable in both eyes. Retinal acuity meter was 20/20 in both eyes, and manifest refraction was plano -1.25 × 105 20/40, J3 in the right eye and +0.50 × 20/25, J1 in the left eye. Pertinent findings on slitlamp examination included temporal iris atrophy and transillumination defects greater in the right eye than the left eye, peripupillary pseudoexfoliative changes in both eyes, significant inferior subluxation of a diffractive 3-piece posterior chamber IOL in the capsular bag with lens-pitting peripherally and few central, moderate pseudophacodonesis, and an open posterior capsule in the right eye. In the left eye, she had mild inferior subluxation of a single-piece acrylic diffractive IOL in the capsular bag with moderate pseudophacodonesis and an open posterior capsule (Figure 1JOURNAL/jcrs/04.03/02158034-202403000-00019/figure1/v/2024-02-20T193212Z/r/image-tiff). All other anterior segment findings were unremarkable. On dilated posterior examination, she had a cup-to-disc ratio of 0.50 in the right eye and 0.65 in the left eye without edema hemorrhage or pallor. There were attenuated vessels in both eyes, posterior vitreous detachment in both eyes, and a few small drusen peripherally in both eyes. There was retinal pigment epithelium irregularity and dropout parafoveal in the right eye and subfoveal in the left eye (Figure 2). There was no evidence of macular edema, subretinal fluid, choroidal thickening, or neovascular membranes. The periphery was unremarkable in both eyes.JOURNAL/jcrs/04.03/02158034-202403000-00019/figure2/v/2024-02-20T193212Z/r/image-tiff What testing would you obtain preoperatively to help guide your decision-making? How would you counsel the patient regarding comorbid conditions and expectations?

2D layered materials with broken inversion symmetry are being extensively pursued as  spin source layers to realize high-efficiency magnetic switching. Such low-symmetry layered systems are, however, scarce. In addition, most layered magnets with perpendicular magnetic anisotropy show a low Curie temperature. Here, the experimental observation of spin-orbit torque magnetization self-switching at room temperature in a layered polar ferromagnetic metal, Fe2.5 Co2.5 GeTe2 is reported. The spin-orbit torque is generated from the broken inversion symmetry along the c-axis of the crystal. These results provide a direct pathway toward applicable 2D spintronic devices.

CRISPR genome editing approaches theoretically enable researchers to define the function of each human gene in specific cell types, but challenges remain to efficiently perform genetic perturbations in relevant models. In this work, we develop a library cloning protocol that increases sgRNA uniformity and greatly reduces bias in existing genome-wide libraries. We demonstrate that our libraries can achieve equivalent or better statistical power compared to previously reported screens using an order of magnitude fewer cells. This improved cloning protocol enables genome-scale CRISPR screens in technically challenging cell models and screen formats.

BACKGROUND: Cancer health research relies on large-scale cohorts to derive generalizable results for different populations. While traditional epidemiological cohorts often use costly random sampling or self-motivated, preselected groups, a shift toward health system-based cohorts has emerged. However, such cohorts depend on participants remaining within a single system. Recent consumer engagement models using smartphone-based communication, driving projects, and social media have begun to upend these paradigms. METHODS: We initiated the Healthy Oregon Project (HOP) to support basic and clinical cancer research. HOP study employs a novel, cost-effective remote recruitment approach to effectively establish a large-scale cohort for population-based studies. The recruitment leverages the unique email account, the HOP website, and social media platforms to direct smartphone users to the study app, which facilitates saliva sample collection and survey administration. Monthly newsletters further facilitate engagement and outreach to broader communities. RESULTS: By the end of 2022, the HOP has enrolled approximately 35,000 participants aged 18-100 years (median = 44.2 years), comprising more than 1% of the Oregon adult population. Among those who have app access, ∼87% provided consent to genetic screening. The HOP monthly email newsletters have an average open rate of 38%. Efforts continue to be made to improve survey response rates. CONCLUSION: This study underscores the efficacy of remote recruitment approaches in establishing large-scale cohorts for population-based cancer studies. The implementation of the study facilitates the collection of extensive survey and biological data into a repository that can be broadly shared and supports collaborative clinical and translational research.

Stabilization of topological spin textures in layered magnets has the potential to drive the development of advanced low-dimensional spintronics devices. However, achieving reliable and flexible manipulation of the topological spin textures beyond skyrmion in a two-dimensional magnet system remains challenging. Here, we demonstrate the introduction of magnetic iron atoms between the van der Waals gap of a layered magnet, Fe3GaTe2, to modify local anisotropic magnetic interactions. Consequently, we present direct observations of the order-disorder skyrmion lattices transition. In addition, non-trivial topological solitons, such as skyrmioniums and skyrmion bags, are realized at room temperature. Our work highlights the influence of random spin control of non-trivial topological spin textures.

Proper neurological function relies on the cellular and molecular microenvironment of the brain, with perturbations of this environment leading to neurological disorders. However, studying the microenvironments of neurological tissue has proven difficult because of its inherent complexity. Both the cell type and metabolomic underpinnings of the cell have crucial functional roles, thus making multimodal characterization methods key to acquiring a holistic view of the brains microenvironment. This study investigates methods for combining matrix-assisted laser desorption/ionization mass spectrometry imaging (MALDI MSI) and immunofluorescence (IF) microscopy to enable the concurrent investigation of cell types and lipid profiles on the same sample. In brief, 1,5-diaminonaphthalene (DAN), α-cyano-4-hydroxy-cinnamic acid (CHCA), and 2,5-dihydroxybenzoic acid (DHB) were tested in addition to instrument-specific parameters for compatibility with IF. Alternatively, the effects of IF protocols on MALDI MSI were also tested, showing significant signal loss with all tested permutations. Ultimately, the use of CHCA for MALDI MSI resulted in the best IF images, while the use of DAN gave the lowest quality IF images. Overall, increasing the laser power and number of shots per laser burst resulted in the most tissue ablation. However, optimized parameter settings allowed for minimal tissue ablation while maintaining sufficient MALDI MSI signal.

The meeting held presentations and discussion about three locally developed and/or open source catalog projects. Ross Shanley-Roberts, Miami University, Ohio, gave a detailed history, technical overview and description of SolrPac (http://beta.lib.muohio.edu). Bess Sadler, University of Virginia, gave a detailed history, technical overview and presentation on the open source OPAC known as Blacklight. Chris Barr and Andrew Nagy of Villanova discussed the VuFind (http://www.Vufind.org/demo) project.

Abstract Topical medical therapy is the most common approach to the treatment of many ocular conditions. While effective, topical therapy has numerous important limitations. Eye drops can have unpleasant or even dangerous side effects, are often difficult to self-administer, and the application of multiple drops per day, possibly from multiple different bottles, can be burdensome. Perhaps the most important limitation of topical medical therapy is non-adherence, a complex multifactorial behavior that increases the risk of poor outcomes associated with undertreatment. There is growing interest in a class of therapeutics termed “procedural pharmaceuticals” (PPs), which remove the responsibility of self-dosing from patients. An array of PPs are available for the treatment of a variety of ocular conditions, such as those for glaucoma, retina, and cataract surgery; and many more will emerge in coming years. A paradigm shift away from patient-administered therapy toward provider-administered therapy will have important implications for both providers and patients. This paper explores the impact that PPs have had, and will have, on the clinical practice of ophthalmology.

Students often struggle in the transition from high school to college. One component of this struggle is adjusting study habits to navigate new academic expectations. Another is establishing new relationships in college that can support their emotional well-being and academic success. We administered surveys consisting primarily of open-ended questions to students taking an introductory physics course in order to gain insight into students' study habits and support structures and how they change from high school to college. We find that many students learn that they need to dedicate more time outside of class to studying in order to succeed in college. Many students trying to improve their performance report practicing more, but our results suggest that more practice alone is not sufficient; rather, students were able to increase their performance and satisfaction in the course by engaging more deeply with the material. Regarding support structures, we find that in high school, students find their teachers highly supportive and accessible, but they are less likely to approach their college professors for help. Meanwhile, many students find peers to be an important source of support in college as the amount of support they receive from their families diminishes with distance from home. Gaining a better understanding of students' study habits, support structures, and how they conceptualize them can help us design course structures and messaging that can more effectively help students develop strong learning strategies and social networks.