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The efficient use of reversible thermal effects in magnetocaloric, electrocaloric, and elastocaloric materials is a promising avenue that can lead to a substantially increased efficiency of refrigeration and heat pumping devices, most importantly, those used in household and commercial cooling applications near ambient temperature. A proliferation in caloric material research has resulted in a wide array of materials where only the isothermal change in entropy in response to a handful of different field strengths over a limited range of temperatures has been evaluated and reported. Given the abundance of such data, there is a clear need for a simple and reliable figure of merit enabling fast screening and down-selection to justify further detailed characterization of those material systems that hold the greatest promise. Based on the analysis of several well-known materials that exhibit vastly different magnetocaloric effects, the Temperature averaged Entropy Change is introduced as a suitable early indicator of the material’s utility for magnetocaloric cooling applications, and its adoption by the caloric community is recommended. [ABSTRACT FROM AUTHOR]

Objective: To assess the feasibility and acceptability of an educational sleep-promoting intervention (Sleep Coach Jr.) for school-aged children (ages 5-9) with type 1 diabetes (T1D) and their parents.Methods: Parents and children (N = 39 dyads, mean child age = 8 years, 64% girls,) were randomized to either the Sleep Coach Jr. intervention, consisting of educational materials and three individual phone calls (N = 20), or the Standard Care condition (N = 19). Data were collected at enrollment and 3 months later. Children and parents wore actigraphy devices to obtain an objective measure of sleep characteristics, and parents completed questionnaire measures of sleep quality and psychosocial outcomes. Clinical data (i.e., hemoglobin A1c, glucose data) were obtained from children's medical records.Results: Feasibility and acceptability of the study were demonstrated to be high; all three sessions were completed by 80% of parents randomized to the Sleep Coach Jr. intervention, and 90% of parents completed follow-up data at 3 months. Parents reported high levels of satisfaction with the study and identified barriers to participation. No changes were observed in children's sleep or diabetes outcomes, but parental sleep quality and well-being improved.Conclusions: A brief, behavioral sleep-promoting intervention is feasible and acceptable for school-aged children with T1D and their parents. A larger trial is needed to evaluate efficacy of the intervention. [ABSTRACT FROM AUTHOR]

Presents a study which detailed the results of structural, chemical, and extreme ultraviolet characterization of Si/Mo multilayers grown by sputtering and by UHV evaporation. Reason for the variation in the deposition conditions; Techniques used; Function of wavelength.

The bias dependence of tunneling magnetoresistance oscillations due to dynamic resonant tunneling in CoFeB/MgO/NiFe magnetic tunnel junctions was studied as functions of temperature and the relative magnetization angle of the two magnetic layers. The effect of temperature is consistent with thermal smearing, while that of the relative magnetic orientation was typical of a spin valve. A model of tunneling between spin-split free electron bands using the exact solution of the Schrödinger equation for a trapezoidal tunnel barrier agrees with experiment, underscoring the simplicity of dynamic resonant tunneling. [ABSTRACT FROM AUTHOR]

Summary: Background: Symptom association probability (SAP) is thought to distinguish reflux hypersensitivity from functional disorders. A diagnosis of hypersensitive oesophagus (SAP‐positive) indicates that gastro‐oesophageal reflux disease (GERD) is the cause of continued symptoms. Aim: To conduct an analysis of pH and symptom criteria that lead to a diagnosis of SAP‐positivity Methods: We calculated SAP for 205 patients with GERD symptoms refractory to proton pump inhibitor (PPI) therapy who underwent endoscopy with wireless pH monitoring from 2007 to 2014. Patients were divided into three groups: pH‐negative with no oesophagitis (n = 45), pH‐positive with no oesophagitis (n = 130), and patients with oesophagitis (n = 30). We constructed a 2 × 2 table of symptom and reflux event association and quantified the number of 2‐minute intervals for each of the 2 × 2 variables that distinguished SAP‐positive from SAP‐negative. In a separate cohort of 58 patients who had undergone anti‐reflux surgery, we evaluated the effects of pre‐surgery SAP. Results: The difference in symptom association parameters that led to a diagnosis of an SAP‐positive was small (2.98% in oesophagitis‐positive; 1.56% in oesophagitis‐negative/pH‐positive; 0.48% in oesophagitis‐negative/pH‐negative). In the pH‐negative/oesophagitis‐negative group, a difference of 0.48% led to a diagnosis of hypersensitivity. There was significant variability in SAP values between day 1 and day 2 of pH testing in all groups, with the greatest in the oesophagitis‐positive group, despite objective evidence for reflux (27% in oesophagitis‐positive, 19% pH‐positive/oesophagitis‐negative, and 7% in pH‐negative/oesophagitis‐negative). Pre‐surgery SAP was not associated with response to anti‐reflux surgery. Conclusion: In PPI‐refractory GERD, SAP cannot accurately distinguish reflux hypersensitivity from functional oesophageal symptoms. [ABSTRACT FROM AUTHOR]

Advances in reducing the resistance and enhancing the magnetoresistance (MR%) of the magnetic tunnel junction (MTJ) material has made it useful for magnetoresistive random access memory as well as magnetic field sensing applications. One of the most important aspects for producing the MTJ material is the method used for forming the tunnel barrier, and its impact on the properties of MTJ such as resistance and area product (RA), MR%, and RA uniformity across a large area. We have explored forming the aluminum oxide tunnel barrier with air; reactive sputtering; plasma oxidation with plasma source; plasma oxidation with power introduced from the target side; and plasma oxidation with power introduced from the substrate side. Our results show that all techniques can be made to work. Plasma oxidation is favored due to its simplicity and manufacturing compatibility. It was also discovered that different oxidation methods used in this study caused little difference in MTJ resistance uniformity. The latter is mainly determined by the Al metal-thickness uniformity. Modeling based on Simmons’ theory supports our experimental finding. This illustrates the importance in improving Al metal-film uniformity for producing MTJ with ultra-uniform resistance. © 2000 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Presents information on study which explored the dependence of magnetoresistance on the thicknesses of each magnetic layer in bottom-pinned spin valves on nickel oxide and for comparison, in FeMn top-pinned spin valves. Experimental details; Results and discussion.

Focuses on a study which performed magnetization measurements on multilayered iron-silicon, cobalt-silicon, and nickel-silicon films to examine the interplay between atomic structure and magnetic behavior. Discussion on the use of direct current sputtering to produce the samples; Verification of nominal preparation thickness; Relationship between saturation magnetization and thickness; Details of results; Comparison of findings with related studies.