3D imaging of magnetic domains in Nd2Fe14B using scanning hard X-ray nanotomography.

Nanoscale structural and electronic heterogeneities are prevalent in condensed matter physics. Investigating these heterogeneities in 3D has become an important task for understanding material properties. To provide a tool to unravel the connection between nanoscale heterogeneity and macroscopic emergent properties in magnetic materials, scanning transmission X-ray microscopy (STXM) is combined with X-ray magnetic circular dichroism. A vector tomography algorithm has been developed to reconstruct the full 3D magnetic vector field without any prior noise assumptions or knowledge about the sample. Two tomographic scans around the vertical axis are acquired on single-crystalline Nd2Fe14B pillars tilted at two different angles, with 2D STXM projections recorded using a focused 120 nm X-ray beam with left and right circular polarization. Image alignment and iterative registration have been implemented based on the 2D STXM projections for the two tilts. Dichroic projections obtained from difference images are used for the tomographic reconstruction to obtain the 3D magnetization distribution at the nanoscale.

Comparative Efficacy of Adjuvant Nonopioid Analgesia in Adult Cardiac Surgical Patients: A Network Meta-Analysis.

OBJECTIVES: To compare the relative efficacy of adjuvant nonopioid analgesic regimens in adult cardiac surgical patients. DESIGN: This frequentist, random-effects network meta-analysis (NMA) was prospectively registered on PROSPERO (CRD42021282913) and conducted according to the Preferred Reporting Items for Systematic Review and Meta-Analyses for Network Meta-Analyses (PRISMA-NMA). The risk of bias (RoB) and confidence of evidence were assessed by RoB 2 and Confidence in Network Meta-Analysis, respectively. Relevant databases were searched from inception to October 9, 2021. SETTING: A total of 124 (N = 26,257) randomized controlled trials were included, of which 110 were analyzed. PARTICIPANTS: Trials enrolling adults (≥18 years of age) undergoing cardiac surgery that compared nonopioid analgesics against other nonopioid analgesics, placebo, or no additional treatment, as adjuvants to standard analgesic management, and reported at least 1 of the outcomes of interest. MEASUREMENT AND MAIN RESULTS: Outcomes of interest included resting postoperative pain scores at 24 hours. Compared with standard care and/or placebo, pain scores were reduced significantly by 10 different regimens, including acetaminophen (N = 176; mean difference [MD] -0.66 points, 95% CI -1.16 to -0.15 points; high confidence), magnesium (N = 323; -0.05 points, 95% CI -0.07 to -0.02 points; high confidence), gabapentin (N = 96; MD -0.40 points, 95% CI -0.71 to -0.09; moderate confidence), and clonidine (N = 64; MD v0.38 points, 95% CI -0.73 to v0.04 points; moderate confidence). Indomethacin, diclofenac, magnesium, and gabapentin significantly reduced 24-hour opioid consumption. Four regimens significantly decreased the intensive care unit length of stay. Hydrocortisone, dexmedetomidine, and clonidine significantly decreased the duration of mechanical ventilation. Magnesium decreased, while methylprednisolone significantly increased, the risk of myocardial infarction. CONCLUSIONS: Given the increasing emphasis on enhanced recovery after surgery(ERAS) protocols and the eventual goal of limiting opiate prescriptions postoperatively, the authors' data suggested far greater use of nonopioid adjuncts to minimize pain and enhance recovery following cardiac surgery.

From Quasicrystals to Crystals with Interpenetrating Icosahedra in Ca-Au-Al: In Situ Variable-Temperature Transformation.

The irreversible transformation from an icosahedral quasicrystal (i-QC) CaAu4.39Al1.61 to its cubic 2/1 crystalline approximant (CA) Ca13Au56.31(3)Al21.69 (CaAu4.33(1)Al1.67, Pa3̅ (No. 205); Pearson symbol: cP728; a = 23.8934(4)), starting at ∼570 °C and complete by ∼650 °C, is discovered from in situ, high-energy, variable-temperature powder X-ray diffraction (PXRD), thereby providing direct experimental evidence for the relationship between QCs and their associated CAs. The new cubic phase crystallizes in a Tsai-type approximant structure under the broader classification of polar intermetallic compounds, in which atoms of different electronegativities, viz., electronegative Au + Al vs electropositive Ca, are arranged in concentric shells. From a structural chemical perspective, the outermost shell of this cubic approximant may be described as interpenetrating and edge-sharing icosahedra, a perspective that is obtained by splitting the traditional structural description of this shell as a 92-atom rhombic triacontahedron into an 80-vertex cage of primarily Au [Au59.86(2)Al17.14□3.00] and an icosahedral shell of only Al [Al10.5□1.5]. Following the proposal that the cubic 2/1 CA approximates the structure of the i-QC and on the basis of the observed transformation, an atomic site analysis of the 2/1 CA, which shows a preference to maximize the number of heteroatomic Au-Al nearest neighbor contacts over homoatomic Al-Al contacts, implies a similar outcome for the i-QC structure. Analysis of the most intense reflections in the diffraction pattern of the cubic 2/1 CA that changed during the phase transformation shows correlations with icosahedral symmetry, and the stability of this cubic phase is assessed using valence electron counts. According to electronic structure calculations, a cubic 1/1 CA, "Ca24Au88Al64" (CaAu3.67Al2.67) is proposed.

Phase separation in necrotic cells.

Necrotic cells are known to develop characteristic membrane blebs. We measured protein concentration within necrotic blebs and found that it can be reduced by as much as twenty-fold compared to the main cell body (CB). These results raise two questions: 1. Why do proteins vacate the bleb? 2. How can osmotic equilibrium be maintained between the bleb and CB? Our photobleaching and ultracentrifugation experiments indicate extensive protein aggregation. We hypothesize that protein aggregation within the CB shifts the chemical equilibrium and draws proteins out of the bleb; at the same time, aggregation reduces the effective molar concentration of protein in the CB, so that osmotic equilibrium between high-protein CB and low-protein necrotic blebs becomes possible.

Outcomes of Patients with a Mechanical Heart Valve and Poor Anticoagulation Control on Warfarin.

BACKGROUND: Patients with a mechanical heart valve (MHV) require oral anticoagulation. Poor anticoagulation control is thought to be associated with adverse outcomes, but data are limited. OBJECTIVE: To assess the risks of clinical outcomes in patients with a MHV and poor anticoagulation control on warfarin. METHODS: We conducted a retrospective study of consecutive patients undergoing MHV implantation at a tertiary care center (2010-2019). Primary outcome was a composite of ischemic stroke, systemic embolism, or prosthetic valve thrombosis. Major bleeding and death were key secondary outcomes. We constructed multivariable regression models to assess the association between time in therapeutic range (TTR) on warfarin beyond 90 days after surgery with outcomes. RESULTS: We included 671 patients with a MHV (80.6% in aortic, 14.6% in mitral position; mean age 61 years, 30.3% female). Median follow-up was 4.9 years, mean TTR was 62.5% (14.5% TTR <40%, 24.6% TTR 40-60%, and 61.0% TTR >60%). Overall rates of the primary outcome, major bleeding, and death were 0.73, 1.41, and 1.44 per 100 patient-years. Corresponding rates for patients with TTR <40% were 1.31, 2.77, and 3.22 per 100 patient-years. In adjusted analyses, every 10% decrement in TTR was associated with a 31% increase in hazard for the primary outcome (hazard ratio [HR]: 1.31, 95% confidence interval [CI]: 1.13-1.52), 34% increase in major bleeding (HR: 1.34, 95% CI: 1.17-1.52), and 32% increase in death (HR: 1.32, 95% CI: 1.11-1.57). CONCLUSION: In contemporary patients with a MHV, poor anticoagulation control on warfarin was associated with increased risks of thrombotic events, bleeding, and death.

Everyday Discrimination and HIV Testing Among Partnered Latino/x Sexual Minority Men in the United States: A Stratified Analysis by Birth Location.

We examined the association between everyday discrimination and HIV testing patterns-current (≤ 6 months), recent (7-12 months), and delayed (> 12 months or never tested)-among partnered Latino/x sexual minority men (SMM). Multinomial regression analyses revealed that in the full sample (N = 484) experiencing discrimination based on sexual orientation and race/ethnicity attributions concurrently (vs. no discrimination) was associated with higher odds of delayed (vs. current) HIV testing (AOR = 2.6, 95% CI [1.0, 6.7]). Similarly, in the subset of Latino/x SMM born outside the mainland U.S. (n = 209), experiencing concurrent sexual orientation- and race/ethnicity-based discrimination (vs. no discrimination) was associated with higher odds of recent (AOR = 12.4, 95% CI [1.3, 115.7]) and delayed HIV testing (AOR = 7.3, 95% CI [1.6, 33.0]), compared with current testing. Findings suggest that addressing discrimination may improve HIV testing uptake among partnered Latino/x SMM, particularly those born outside the U.S.

A review of mentoring deaf and hard-of-hearing scholars.

Diversification of the scientific workforce usually focuses on recruitment and retention of women and underrepresented racial and ethnic minorities but often overlooks deaf and hard-of hearing (D/HH) persons. Usually classified as a disability group, such persons are often members of their own sociocultural linguistic minority and deserve unique support. For them, access to technical and social information is often hindered by communication- and/or language-centered barriers, but securing and using communication access services is just a start. Critical aspects of training D/HH scientists as part of a diversified workforce necessitates: (a) educating hearing persons in cross-cultural dynamics pertaining to deafness, sign language, and Deaf culture; (b) ensuring access to formal and incidental information to support development of professional soft skills; and (c) understanding that institutional infrastructure change may be necessary to ensure success. Mentorship and training programs that implement these criteria are now creating a new generation of D/HH scientists.

Fatty acids differentially modulate insulin-stimulated endothelial nitric oxide production by an Akt-independent pathway.

BACKGROUND: Insulin increases endothelial nitric oxide (NO) production by activating endothelial nitric oxide synthase (eNOS) through protein kinase B (Akt)-mediated phosphorylation of serine residue 1179 (p-eNOS serine 1179). Because fatty acids modulate insulin-stimulated Akt signaling cascades in smooth muscle cells, we hypothesized that fatty acids would differentially regulate endothelial Akt signaling, eNOS phosphorylation, and NO production. METHODS: Porcine pulmonary artery endothelial cells (PAECs) were treated for 3 hours with 100 microM oleic (18:1) or eicosapentaenoic (20:5) acids or with an equivalent volume of ethanol vehicle (0.1%). PAECs were then treated with graded concentrations (10(9)-10(-5) M) of insulin or incubated overnight (24 hours) in culture medium without fatty acids before insulin treatment. Activation and phosphorylation of Akt and eNOS were determined by immunoblotting. NO production was measured with a chemiluminescence NO analyzer or with a NO-selective carbon fiber microelectrode. RESULTS: Insulin-stimulated Akt phosphorylation, eNOS phosphorylation, and NO production. The phosphatidylinositol-3 kinase inhibitor wortmannin attenuated insulin-stimulated Akt activation and NO production. Treatment with the omega-3 fatty acid 20:5, but not 18:1, enhanced insulin-stimulated NO production but failed to alter insulin-stimulated Akt activation or eNOS serine 1179 phosphorylation. CONCLUSION: Individual fatty acyl species have distinct effects on insulin-stimulated endothelial NO production. Although fatty acids alter Akt signaling in muscle cells, the current results indicate that fatty acids do not modulate endothelial NO production through alterations in insulin-stimulated, Akt-mediated eNOS phosphorylation.

Characterization and 2D self-assembly of CdSe quantum dots at the air-water interface.

Langmuir film properties, UV-vis spectroscopy, epifluorescence microscopy, and transmission electron microscopy were used to study CdSe quantum dots (QDs) in 2D. By combining these results, it was possible to determine the molar absorptivity, limiting nanoparticle area, luminescence property, and arrangement of the QDs in the monolayer films at the air-water interface. Either trioctylphosphine oxide (TOPO) or 1-octadecanethiol (ODT) stabilized the QDs. The data collected reveal that TOPO forms close-packed monolayers on the surface of the QDs and that ODT-stabilized QDs undergo alkyl chains interdigitation. It was also found that varying the nanoparticle size, nature of surfactant, surface pressure, and mixed monolayers could help engineer the 2D self-assembly of the QDs at the air-water interface. Of practical importance is the transfer of these monolayer films onto hydrophilic or hydrophobic solid substrates, which could be successfully accomplished via the Langmuir-Blodgett film deposition technique.