1,258 research outputs found
Non-collinear single-electron spin-valve transistors
We study interaction effects on transport through a small metallic cluster
connected to two ferromagnetic leads (a single-electron spin-valve transistor)
in the "orthodox model" for the Coulomb blockade. The non-local exchange
between the spin accumulation on the island and the ferromagnetic leads is
shown to affect the transport properties such as the electric current and
spin-transfer torque as a function of the magnetic configuration, gate voltage,
and applied magnetic field.Comment: 4 pages, 3 figure
Return on interactivity: The impact of online agents on newcomer adjustment
As service offerings grow in both range and complexity, how service providers and their customers interact is becoming increasingly important. In response to the challenge of optimizing these interactions, companies have introduced sophisticated online "socialization agents," whose purpose is to help new customers more effectively adjust to and function within the service environment. The objective of these online agents, or virtual employees, is to help customers evaluate new or unfamiliar service offerings, as well as help companies achieve greater levels of service delivery and financial performance. To investigate this, the authors analyze the process by which online agents help both new and current customers adjust to and function within new, unfamiliar, or complex service contexts. They examine the impact of an online agent on account performance in the banking industry. They find that both interaction style and content of the online agent significantly influence the newcomer adjustment process over time, which in turn influences firm-level performance
A personalized eHealth intervention for lifestyle changes in patients with cardiovascular disease::Randomized controlled trial
BACKGROUND: Behavior change methods involving new ambulatory technologies may improve lifestyle and cardiovascular disease outcomes. OBJECTIVE: This study aimed to provide proof-of-concept analyses of an intervention aiming to increase (1) behavioral flexibility, (2) lifestyle change, and (3) quality of life. The feasibility and patient acceptance of the intervention were also evaluated. METHODS: Patients with cardiovascular disease (N=149; mean age 63.57, SD 8.30 years; 50/149, 33.5% women) were recruited in the Do Cardiac Health Advanced New Generation Ecosystem (Do CHANGE) trial and randomized to the Do CHANGE intervention or care as usual (CAU). The intervention involved a 3-month behavioral program in combination with ecological momentary assessment and intervention technologies. RESULTS: The intervention was perceived to be feasible and useful. A significant increase in lifestyle scores over time was found for both groups (F2,146.6=9.99; P<.001), which was similar for CAU and the intervention group (F1,149.9=0.09; P=.77). Quality of life improved more in the intervention group (mean 1.11, SD 0.11) than CAU (mean -1.47, SD 0.11) immediately following the intervention (3 months), but this benefit was not sustained at the 6-month follow-up (interaction: P=.02). No significant treatment effects were observed for behavioral flexibility (F1,149.0=0.48; P=.07). CONCLUSIONS: The Do CHANGE 1 intervention was perceived as useful and easy to use. However, no long-term treatment effects were found on the outcome measures. More research is warranted to examine which components of behavioral interventions are effective in producing long-term behavior change. TRIAL REGISTRATION: ClinicalTrials.gov NCT02946281; https://www.clinicaltrials.gov/ct2/show/NCT02946281
Exchange effects on electron transport through single-electron spin-valve transistors
We study electron transport through single-electron spin-valve transistors in
the presence of non-local exchange between the ferromagnetic leads and the
central normal-metal island. The Coulomb interaction is described with the
orthodox model for Coulomb blockade and we allow for noncollinear lead
magnetization directions. Two distinct exchange mechanisms that have been
discussed in the literature are shown to be of comparable strength and are
taken into account on equal footing. We present results for the linear
conductance as a function of gate voltage and magnetic configuration, and
discuss the response of the system to applied magnetic fields.Comment: 15 pages, 6 figure
Acute phosphate depletion and in vitro rat proximal tubule injury: Protection by glycine and acidosis
Acute phosphate depletion and in vitro rat proximal tubule injury: Protection by glycine and acidosis.The effects of phosphate (PO4) removal from Krebs Henseleit buffer on freshly isolated rat proximal tubules (rPT) were assessed by measuring Ca2+ uptake (nmol/mg protein), cellular adenosine triphosphate (ATP) (nmol/mg), tissue K+ content (nmol/mg) and lactate dehydrogenase (LDH) as an index of cell integrity. Ca2+ uptake increased by 50% in rPT incubated in zero PO4 medium as compared to control (2.6 ±0.1 vs. 3.9 ±0.19, P < 0.001) and LDH release increased 2.5-fold from 14.2 ±0.6 to 31.6 ±1.6%, P < 0.001. Neither verapamil (200 µM) nor mepacrine (50 µM) reduced Ca2+ uptake or decreased LDH release suggesting that the increased Ca2+ uptake was not occurring through potential operated channels and that phospholipase-induced cell injury was not the cause of increased LDH release. Either glycine (2 mM) or extracellular fluid acidosis (pH 7.06), however, significantly diminished rPT injury and Ca2+ uptake. Specifically, as compared to the increased LDH released in untreated, PO4-depleted rPT, LDH release was diminished significantly by glycine treatment (31.0 ±0.9 vs. 15.5 ±1.6%, P < 0.001) or acidosis (30.3 ±0.04 vs. 19.2 ±0.9%, P < 0.01). Ca2+ uptake did not increase in glycine treated tubules (2.6 ±0.1 vs. 2.8 ±0.2 nmol/mg, NS) or in the presence of acidosis (2.6 ±0.1 vs. 2.97 ±0.17 nmol/mg, NS). ATP concentrations were markedly reduced by PO4 depletion (2.8±0.2 vs. 4.8±0.3 nmol/mg, P < 0.001) and remained at low levels during either acidosis or glycine-induced protection. ATP depletion was accompanied by loss of K+ from rPT and this was only modestly attenuated by either glycine or acidosis. Total cell PO4 was not significantly altered, however, perchloric acid (PCA) extractable free PO4 was reduced significantly (33.3 ±4.5 to 15.9 ±3.5 nmol/mg, P < 0.01). The rPT injury, associated with acute PO4 depletion, may be related to Ca2+ uptake since Ca2+ uptake and LDH release were both attenuated by glycine administration or acidosis
The time-dependent rearrangement of the epithelial basement membrane in human skin wounds
In 62 human skin wounds (surgical wounds, stab wounds and lacerations after surgical treatment) we analyzed the immunohistochemical localization of collagen IV in the epithelial basement membrane. In 27 of these wounds the distribution of collagen VII, which represents a specific component of the basement membrane of stratified epithelia, was also analyzed. We were able to demonstrate a virtually identical co-distribution of both collagen IV and VII in the wound area with no significant time-dependent differences in the appearance of both collagen types. Fragments of the epithelial basement membrane could be detected in the wound area from as early as 4 days after wounding and after 8 days a complete restitution of the epithelial basement membrane was observed. In all cases with a wound age of more than 21 days the basement membrane was completely reformed over the former lesional area. The period between 8 and 21 days after wounding was characterized by a wide variability ranging from complete restitution to deposition of basement membrane fragments or total lack of the epidermal basement membrane
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