Prevalence of swallowing difficulties and associated factors in older people with intellectual disabilities.

BACKGROUND: We investigated the prevalence of swallowing difficulties and associated factors in people with intellectual disability. METHODS: We included people aged 50+ receiving care for people with intellectual disabilities. The Dysphagia Disorder Survey (DDS) was used to assess swallowing difficulties. We determined the agreement between the DDS and swallowing difficulties in medical records. We used logistic regression analyses to explore associated factors. RESULTS: One thousand and fifty people were included. The prevalence of swallowing difficulties was 43.8%. Swallowing difficulties were not reported in the medical records of 83.3% of these cases. Frailty (odds ratio (OR) = 4.22, 95% CI = 2.05-8.71), mobility impairment (OR = 2.50, 95% CI = 1.01-6.19), and mealtime dependency (OR = 3.05, 95% CI = 1.10-8.47) were independently associated with swallowing difficulties. CONCLUSION: Swallowing difficulties are prevalent in older people with intellectual disability but may be under-recognised. Frailty may be a good indicator for population-based screening for swallowing difficulties.

The 2021 Magnonics Roadmap.

Magnonics is a budding research field in nanomagnetism and nanoscience that addresses the use of spin waves (magnons) to transmit, store, and process information. The rapid advancements of this field during last one decade in terms of upsurge in research papers, review articles, citations, proposals of devices as well as introduction of new sub-topics prompted us to present the first roadmap on magnonics. This is a collection of 22 sections written by leading experts in this field who review and discuss the current status besides presenting their vision of future perspectives. Today, the principal challenges in applied magnonics are the excitation of sub-100 nm wavelength magnons, their manipulation on the nanoscale and the creation of sub-micrometre devices using low-Gilbert damping magnetic materials and its interconnections to standard electronics. To this end, magnonics offers lower energy consumption, easier integrability and compatibility with CMOS structure, reprogrammability, shorter wavelength, smaller device features, anisotropic properties, negative group velocity, non-reciprocity and efficient tunability by various external stimuli to name a few. Hence, despite being a young research field, magnonics has come a long way since its early inception. This roadmap asserts a milestone for future emerging research directions in magnonics, and hopefully, it will inspire a series of exciting new articles on the same topic in the coming years.

Real-space imaging of non-collinear antiferromagnetic order with a single-spin magnetometer.

Although ferromagnets have many applications, their large magnetization and the resulting energy cost for switching magnetic moments bring into question their suitability for reliable low-power spintronic devices. Non-collinear antiferromagnetic systems do not suffer from this problem, and often have extra functionalities: non-collinear spin order may break space-inversion symmetry and thus allow electric-field control of magnetism, or may produce emergent spin-orbit effects that enable efficient spin-charge interconversion. To harness these traits for next-generation spintronics, the nanoscale control and imaging capabilities that are now routine for ferromagnets must be developed for antiferromagnetic systems. Here, using a non-invasive, scanning single-spin magnetometer based on a nitrogen-vacancy defect in diamond, we demonstrate real-space visualization of non-collinear antiferromagnetic order in a magnetic thin film at room temperature. We image the spin cycloid of a multiferroic bismuth ferrite (BiFeO3) thin film and extract a period of about 70 nanometres, consistent with values determined by macroscopic diffraction. In addition, we take advantage of the magnetoelectric coupling present in BiFeO3 to manipulate the cycloid propagation direction by an electric field. Besides highlighting the potential of nitrogen-vacancy magnetometry for imaging complex antiferromagnetic orders at the nanoscale, these results demonstrate how BiFeO3 can be used in the design of reconfigurable nanoscale spin textures.

The nature of domain walls in ultrathin ferromagnets revealed by scanning nanomagnetometry.

The capacity to propagate magnetic domain walls with spin-polarized currents underpins several schemes for information storage and processing using spintronic devices. A key question involves the internal structure of the domain walls, which governs their response to certain current-driven torques such as the spin Hall effect. Here we show that magnetic microscopy based on a single nitrogen-vacancy defect in diamond can provide a direct determination of the internal wall structure in ultrathin ferromagnetic films under ambient conditions. We find pure Bloch walls in Ta/CoFeB(1 nm)/MgO, while left-handed Néel walls are observed in Pt/Co(0.6 nm)/AlOx. The latter indicates the presence of a sizable interfacial Dzyaloshinskii-Moriya interaction, which has strong bearing on the feasibility of exploiting novel chiral states such as skyrmions for information technologies.

Nanoscale imaging and control of domain-wall hopping with a nitrogen-vacancy center microscope.

The control of domain walls in magnetic wires underpins an emerging class of spintronic devices. Propagation of these walls in imperfect media requires defects that pin them to be characterized on the nanoscale. Using a magnetic microscope based on a single nitrogen-vacancy (NV) center in diamond, we report domain-wall imaging on a 1-nanometer-thick ferromagnetic nanowire and directly observe Barkhausen jumps between two pinning sites spaced 50 nanometers apart. We further demonstrate in situ laser control of these jumps, which allows us to drag the domain wall along the wire and map the pinning landscape. Our work demonstrates the potential of NV microscopy to study magnetic nano-objects in complex media, whereas controlling domain walls with laser light may find an application in spintronic devices.

Understanding nanoscale temperature gradients in magnetic nanocontacts.

We have determined the temperature profile in magnetic nanocontacts under applied current densities typical of spin-torque oscillators (∼10(8) A/cm2). The study combines experimental measurements of the electrical and magnetic properties of the nanocontacts and full three-dimensional simulations of the heat and current flow in these systems. It is found that the quadratic current-induced increase of the resistance due to Joule heating is independent of the applied temperature from 6 to 300 K. In terms of magnetization dynamics, the measured current-induced vortex nucleation, a thermally activated process, is found to be consistent with local temperatures increases of between 147 and 225 K. Simulations reproduce the experimental findings and show that significant thermal gradients exist out to 450 nm from the nanocontact.

Cause of metabolic acidosis in prolonged surgery.

OBJECTIVE: The intraoperative development of metabolic acidosis is frequently attributed to hypovolemia, tissue hypoperfusion, and lactic acidosis. In this study, dilutional acidosis was evaluated as a possible mechanism for the routine development of intraoperative acidosis in noncardiac, nonvascular surgery patients. DESIGN: Prospective, observational study. SETTING: University-affiliated Veteran's Affairs Medical Center and a staff model, health maintenance organization hospital. PATIENTS: Twelve patients undergoing prolonged surgical procedures expected to last > or = 4 hrs were enrolled in the study. INTERVENTIONS: Perioperative management was based on the judgment of the attending anesthesiologist and surgeon without knowledge of the study's intent. MEASUREMENTS AND MAIN RESULTS: Arterial blood gas parameters, serum electrolytes, and urine electrolytes were measured pre- and postoperatively. Pulmonary artery catheters were placed for hemodynamic measurement and oxygen delivery calculations. Plasma volume was measured both pre- and postoperatively, using the Evans blue dye dilution technique. Although significant changes in lactate level (1.1 +/- 0.6-1.8 +/- 1.0) occurred, the change was not large enough to explain the degree of change in base excess (0.8 +/- 2.3 to -2.7 +/- 2.9). Chloride levels significantly increased (106 +/- 3-110 +/- 5) with a correlation (r2 = .92; p < .0001) between the degree of change in chloride and the degree of change in base excess. Plasma volume did not change. Furthermore, a correlation between the volume of normal saline administered and the change in base excess was found (r2 = .86; p < .0001), although no correlation was found with Ringer's lactate solution. An even stronger correlation was noted when the total chloride amount administered was compared with the change in base excess (r2 = .93; p < .0001). CONCLUSIONS: In this patient population, a common source of increasing base deficit is related to chloride administration. The largest source of chloride is usually normal saline. Classically, dilutional acidosis would explain the predominance of this acidotic change; however, no increase in plasma volume occurred. The absence of plasma volume change would suggest that the mechanism postulated to result in dilutional acidosis is incomplete. The common treatment of administering more fluid for intraoperative acidosis may be inappropriate, may have caused the acidosis, and may further exacerbate the acidosis. Chloride levels should be assessed whenever a metabolic acidosis is seen perioperatively.

Ca2+ transport in mitochondria of the ciliate protozoan Tetrahymena pyriformis.

Mitochondria isolated from the late-exponential non-shaken culture of the ciliate protozoan Tetrahymena pyriformis GL was investigated. The presence of energy-dependent Ca2+ transport system was shown. In the main the properties of this system have been essentially the same as in mitochondria of vertebrate organisms. The isolated mitochondria contained 23 +/- 5 ng-ion Ca2+ per mg of protein. The intramitochondrial free concentration of Ca2+ was measured in the presence of uncoupler FCCP with the use of fluorescent Ca2+ chelator chlortetracycline and null point titration method. In the absence of phosphate, free [Ca2+] varied from 1 to 2.5 mM depending on the internal Ca2+ content. In the presence of 2 mM phosphate, free [Ca2+]in has not exceeded 0.1-0.3 mM. It was shown that ruthenium red and Mg2+ in different manner have an inhibitory effect on Ca2+ transport. Besides this, Mg2+ also has a stabilizing effect on mitochondria, possibly, by preventing passive ions leaks across the membrane.