Magnetic properties of antiferromagnetically coupled CoFeB/Ru/CoFeB

This work reports on the thermal stability of two amorphous CoFeB layers coupled antiferromagnetically via a thin Ru interlayer. The saturation field of the artificial ferrimagnet which is determined by the coupling, J, is almost independent on the annealing temperature up to more than 300 degree C. An annealing at more than 325 degree C significantly increases the coercivity, Hc, indicating the onset of crystallization.Comment: 4 pages, 3 figure

Proof of a three-loop relation between the Regge limits of four-point amplitudes in N=4 SYM and N=8 supergravity

A previously proposed all-loop-orders relation between the Regge limits of four-point amplitudes of N=4 supersymmetric Yang-Mills theory and N=8 supergravity is established at the three-loop level. We show that the Regge limit of known expressions for the amplitudes obtained using generalized unitarity simplifies in both cases to a (modified) sum over three-loop ladder and crossed-ladder scalar diagrams. This in turn is consistent with the result obtained using the eikonal representation of the four-point gravity amplitude. A possible exact three-loop relation between four-point amplitudes is also considered.Comment: 30 pages, 7 figure

Antiferromagnetically coupled CoFeB/Ru/CoFeB trilayers

This work reports on the magnetic interlayer coupling between two amorphous CoFeB layers, separated by a thin Ru spacer. We observe an antiferromagnetic coupling which oscillates as a function of the Ru thickness x, with the second antiferromagnetic maximum found for x=1.0 to 1.1 nm. We have studied the switching of a CoFeB/Ru/CoFeB trilayer for a Ru thickness of 1.1 nm and found that the coercivity depends on the net magnetic moment, i.e. the thickness difference of the two CoFeB layers. The antiferromagnetic coupling is almost independent on the annealing temperatures up to 300 degree C while an annealing at 350 degree C reduces the coupling and increases the coercivity, indicating the onset of crystallization. Used as a soft electrode in a magnetic tunnel junction, a high tunneling magnetoresistance of about 50%, a well defined plateau and a rectangular switching behavior is achieved.Comment: 3 pages, 3 figure

Interface sharpening in CoFeB magnetic tunnel junctions

We report grazing incidence x-ray scattering evidence for sharpening of the interface between amorphous Co60Fe20B20 and AlOx during in situ annealing below the Co60Fe20B20 crystallization temperature. Enhancement of the interference fringe amplitude in the specular scatter and the absence of changes in the diffuse scatter indicate that the sharpening is not a reduction in topological roughness but a reduction in the width of the chemical composition profile across the interface. The temperature at which the sharpening occurs corresponds to that at which a maximum is found in the tunneling magnetoresistance of magnetic tunnel junctions

S-COL: A Copernican turn for the development of flexibly reusable collaboration scripts

Collaboration scripts are usually implemented as parts of a particular collaborative-learning platform. Therefore, scripts of demonstrated effectiveness are hardly used with learning platforms at other sites, and replication studies are rare. The approach of a platform-independent description language for scripts that allows for easy implementation of the same script on different platforms has not succeeded yet in making the transfer of scripts feasible. We present an alternative solution that treats the problem as a special case of providing support on top of diverse Web pages: In this case, the challenge is to trigger support based on the recognition of a Web page as belonging to a specific type of functionally equivalent pages such as the search query form or the results page of a search engine. The solution suggested has been implemented by means of a tool called S-COL (Scripting for Collaborative Online Learning) and allows for the sustainable development of scripts and scaffolds that can be used with a broad variety of content and platforms. The tool’s functions are described. In order to demonstrate the feasibility and ease of script reuse with S-COL, we describe the flexible re-implementation of a collaboration script for argumentation in S-COL and its adaptation to different learning platforms. To demonstrate that a collaboration script implemented in S-COL can actually foster learning, an empirical study about the effects of a specific script for collaborative online search on learning activities is presented. The further potentials and the limitations of the S-COL approach are discussed

Socio-cognitive scaffolding with collaboration scripts: a meta-analysis

Scripts for computer-supported collaborative learning (CSCL) offer socio-cognitive scaffolding for learners to engage in collaborative activities that are considered beneficial for learning. Yet, CSCL scripts are often criticized for hampering naturally emerging collaboration. Research on the effectiveness of CSCL scripts has shown divergent results. This article reports a meta-analysis about the effects of CSCL scripts on domain-specific knowledge and collaboration skills. Results indicate that CSCL scripts as a kind of socio-cognitive scaffolding can enhance learning outcomes substantially. Learning with CSCL scripts leads to a small positive effect on domain-specific knowledge (d = 0.20) and a large positive effect on collaboration skills (d = 0.95) compared to unstructured CSCL. Further analyses reveal that CSCL scripts are particularly effective for domain-specific learning when they prompt transactive activities (i.e., activities in which a learner’s reasoning builds on the contribution of a learning partner) and when they are combined with additional content-specific scaffolding (worked examples, concept maps, etc.). Future research on CSCL scripts should include measures of learners’ internal scripts (i.e., prior collaboration skills) and the transactivity of the actual learning process

Rapid Detection of Infestation of Apple Fruits by the Peach Fruit Moth, Carposina sasakii Matsumura, Larvae Using a 0.2-T Dedicated Magnetic Resonance Imaging Apparatus

Infestation of harvested apple fruits by the peach fruit moth (Carposina sasakii Matsumura) was studied using a dedicated magnetic resonance imaging (MRI) apparatus equipped with a 0.2-T permanent magnet. Infested holes on the three-dimensional (3-D) images tracked ecological movements of peach fruit moth larvae within the food fruits, and thus in their natural habitat. Sensitive short solenoid coil and surface coil detectors were devised to shorten measurement times. The short solenoid coil detected infestation holes at a rate of 6.4 s per image by the single-slice 2-D measurement. The multi-slice 2-D measurement provided six slice images of a fruit within 2 min taken by the two detectors. These results indicate that the 0.2-T MRI apparatus allows one to distinguish sound fruits from infested ones, and also as a means for plant protection and the preservation of natural ecological systems in foreign trade

Quantification of Semi-Truck Cab Decontamination

Evidence suggests that the inside of vehicle cabs used for feed delivery may serve as a potential source for disease, yet there are no standardized protocols or scientific evidence for methods of their disinfection. Therefore, the objective of this project was to evaluate commercially available disinfectants and disinfection application methods against PEDV and PRRSV on various surfaces within semi-truck cabs. Three different surface types common in vehicle cabs (fabric, plastic, and rubber) were cut into 4 × 4 inch coupons and inoculated with either PEDV or PRRSV. Once inoculated, surfaces were placed in one of 3 semi-truck cabs and the disinfectant treatment was applied. Disinfectant treatments were as follows: 1) no-disinfectant, 2) hurricane fumigation with 1:256 dilution of Synergize, 3) hurricane fumigation with 1:64 dilution of Intervention, 4) pump sprayer with 1:256 dilution of Synergize, 5) pump sprayer with 1:64 dilution of Intervention, 6) pump sprayer with 10% bleach, 7) no chemical with 10 hr downtime, and 8) gaseous fumigation over a 10 hr period with water-based chlorine dioxide. Once a disinfectant treatment was applied, the coupons were environmentally swabbed and submitted for qPCR duplex analysis for PEDV and PRRSV. There was a significant disinfectant × surface interaction (P \u3c 0.0001) indicating that the disinfectant treatment efficacy differed based on surface. Within rubber surfaces, 10% bleach had a greater Ct value compared to all other treatments (P \u3c 0.05), with the exception of Intervention with hurricane fumigation application, which was intermediate. In both fabric and plastic surfaces, there was no evidence (P \u3e 0.05) of a difference in Ct value between any of the treatments. Additionally, for the no-disinfectant treatment, the Ct value was greater on fabric surfaces compared to plastic and rubber (P \u3c 0.05); fabric was greater than plastic in the Intervention with pump sprayer application treatment (P \u3c 0.05), fabric and rubber greater than plastic in the 10% bleach treatment (P \u3c 0.05); and fabric greater than plastic and rubber in the 10 hr downtime and gaseous fumigation treatments (P \u3c 0.05). There was a significant main effect of disinfectant treatment (P = 0.016), where 10% bleach had a greater Ct value compared to both the control treatment, 10 hr downtime treatment, and Intervention applied using the pump sprayer (P \u3c 0.05). There was a main effect of surface (P \u3c 0.0001) where rubber had a greater Ct value compared to plastic (P \u3c 0.05), and fabric had a greater Ct value compared to both rubber and plastic (P \u3c 0.05). Finally, the Ct value for PRRSV was greater than PEDV (P \u3c 0.0001) when averaged across all surfaces and disinfectant treatments. In summary, these data highlight that it is important to consider the surface of interest when implementing disinfectant protocols. In general, most disinfectant applications were only able to reduce the quantity of detectable virus, but not completely eliminate it from surface. However, additional research is necessary to understand the viability of residual virus on disinfected surfaces

Effects of Dietary Amino Acid Density and Exogenous Protease Inclusion on Growth Performance and Apparent Ileal AA Digestibility in Broilers

Protein is one of the most expensive nutrients in poultry diets. In an effort to minimize feed costs, protein digestion and utilization by the animal must be carried out as efficiently as possible. Therefore, the objective of this study was to evaluate the effects of dietary AA density and exogenous protease inclusion on growth performance and AA digestibility in broilers. Treatments consisted of a 2 × 4 factorial design with main effects of commercial protease (with or without) and digestible Lys (1.12, 1.15, 1.18, or 1.21%). Broiler chicks were housed in 4 Petersime batteries and treatments were randomly assigned to 80 cages within location block, resulting in 10 cages per treatment with 6 chicks per cage at placement. A commercial enzyme complex with 3 proteolytic activities was added to the protease diets at 0.25 lb/ton, and the same inclusion of sand was added to the diets without protease. Diets were balanced by energy and Lys:amino acid ratios. Titanium dioxide was included in the diets at 0.5% as an indigestible marker. On d 20, ileal contents from 2 chicks per cage were collected and composited by cage for calculation of apparent ileal AA digestibility. Growth performance metrics were calculated from cage weights and feed consumption was recorded throughout the experiment, and AA digestibility data were obtained from analysis of ileal contents. Data were analyzed using SAS 9.4 with cage as the experimental unit and cage location as the blocking factor. There was no evidence of an amino acid density × protease interaction (P \u3e 0.05) for BW, ADG or ADFI. There was an amino acid density × protease interaction (quadratic, P \u3c 0.05) for feed conversion ratio (FCR). Chicks fed 1.12 and 1.21% digestible Lys diets with added protease had a 2-point improvement in FCR compared to chicks fed these diets without protease. There was no difference in FCR between birds consuming diets with or without protease when fed 1.15 and 1.18% digestible Lys diets. There was no evidence of difference (P \u3e 0.10) in ADG or ADFI due to dietary amino acid density throughout the feeding period. However, broiler FCR was improved (linear, P \u3c 0.01) by increasing dietary amino acid density from 1.12 to 1.21% digestible Lys. There was no evidence (P \u3e 0.10) of main effect of added protease on BW, ADG, ADFI, or FCR. There was not an amino acid density × protease interaction (P \u3e 0.09) or main effect of dietary amino acid density or protease inclusion (P \u3e 0.12) on apparent ileal digestibility (AID) of Lys, Arg, Met, Cys, Thr, Ile, Leu, Val, or Trp. In conclusion, increasing dietary amino acid density improved FCR in broiler chicks, and the rate of improvement was dependent on the inclusion of an exogenous protease