Low-Temperature Magnetoresistance in Magnesium and Aluminum Containing Small Concentrations of Manganese or Iron

Magnetoresistance measurements in magnetic fileds up to 21 kOe have been made on Mg-Mn, Mg-Cd, Mg-Al, Al-Mn, and Al-Fe alloys in the temperature region of liquid helium. Magnesium alloys containing more than 0.1-at.% Mn which exhibit a resistance maximum and minimum in zero filed, show a negative magnetoresistance, whereas the more dilute samples (0.001-0.1 at. % Mn) show a positive magnetoresistance, the magnitude of which decreases with decreasing temperature. The magnesium alloys containing non-transition element impurities, as well as the aluminum alloys containing transition metal impurities, are found to obey Kohler\u27s rule. From an analysis of these data it is found that the magnetoresistivity of a dilute alloy of magnesium containing manganese, can be considered as the sum of a normal positive magnetoresistivity (obeying Kohler\u27s rule) and an anomalous term which is negative in sign, does not obey Kohler\u27s rule and is presumably due to a magnetic scattering of the conduction electrons. Using values of thes s-d exchange integral and the Coulomb scattering integral derived from an analysis of the zero-field resistivity permits an explanation of the magnetoresistivity based on Kasuya\u27s theory, at temperatures near the Neel point

Magnetoresistivity Behavior of some Dilute Cu-Fe, Cu-Mn, and Cu-Zn Alloys at Liquid Helium Temperatures

Resistance measurements in magnetic fields up to 100 kilo-oersteds have been made on some Cu-Fe, Cu-Mn, and Cu-Zn alloys in the liquid helium temperature range, where the Cu alloys containing paramagnetic impurities exhibit resistance anomalies. The sign of both the transverse and longitudinal magnetoresistivity in Cu-Fe alloys at 4.2°K is positive for alloys containing less than 0.04 at. % Fe and negative for alloys containing more than this concentration of iron. For all of the Cu-Fe alloys studied the magnitude of the magnetoresistance normalized to the zero-field resistivity is larger at 4.2°K than at lower temperatures. The sign of both the transverse and longitudinal magnetoresistivity in a Cu-0.007 at. % Mn alloy at 4.2°K is positive for all magnetic field values. However, at lower temperatures (1.3°K) the same alloy has a negative magnetoresistivity at low fields, which saturates and becomes positive at higher field values. The rate of change of the normalized transverse and longitudinal magnetoresistivity for Cu-Mn is also larger at 4.2°K than at lower temperatures. The magnetoresistivity of the Cu-Zn alloys decreases with decreasing field strength and increasing Zn concentration, with a modified Kohler law fitting the experimental data. The transverse magnetoresistivity is always larger than the longitudinal one, and for the most dilute Cu-Zn alloy the magnitude of both components is of the same order as that of pure Cu. It is found possible empirically to separate the Cu-Mn magnetoresistivity data into a positive and negative component ; however, for the Cu-Fe alloys studied the present analysis proves the existence of a negative component for the more concentrated alloys but does not permit a separation from the total magnetoresistivity effect

Individual Differences in the Neural Signature of Subjective Value Among Older Adults

Some healthy older adults show departures from standard decision-making patterns exhibited by younger adults. We asked if such departures are uniform or if heterogeneous aging processes can designate which older adults show differing decision patterns. Thirty-three healthy older adults with varying decision-making patterns on a complex decision task (the Iowa Gambling Task) completed an intertemporal choice task while undergoing functional magnetic resonance imaging. We examined whether value representation in the canonical valuation network differed across older adults based on complex decision-making ability. Older adults with advantageous decision patterns showed increased activity in the valuation network, including the ventromedial prefrontal cortex (VMPFC) and striatum. In contrast, older adults with disadvantageous decision patterns showed reduced or absent activation in the VMPFC and striatum, and these older adults also showed greater blood oxygen level dependent signal temporal variability in the striatum. Our results suggest that a reduced representation of value in the brain, possibly driven by increased neural noise, relates to suboptimal decision-making in a subset of older adults, which could translate to poor decision-making in many aspects of life, including finance, health and long-term care. Understanding the connection between suboptimal decision-making and neural value signals is a step toward mitigating age-related decision-making impairments

The influence of water in a ration for pigs

Thesis (B.S.)--University of Illinois, 1909.Typescript

Role of s-d Exchange Interactions in Dilute Alloys Exhibiting Both Low-Temperature Resistance Anomalies and Superconductivity

Measurements of the magnetic susceptibility of some dilute Zn-Mn alloys are reported in the temperature range where this alloy system is known to exhibit low-temperature resistance anomalies. All of the alloys studied obey a Curie law with the most concentrated alloy (0.43-at. % Mn) exhibiting deviations in the neighborhood of 6°K. The Curie constant indicates that manganese when dissolved in zinc has a spin value of 3/2 which is temperature-independent between 5 and 273°K. Calculations of the exchange integral J from the magnetic properties of dilute Zn-Mn alloys have been made from the Neel temperature, the magnetoresistivity as a function of field strength and the suppression of the superconducting critical temperature based on theoretical equations which assume a scalar s-d interaction between the paramagnetic ions and conduction electrons. All of the derived values of J lie in the range of (1.4±0.2) ×10^ erg which would lead one to conclude that the magnetic interaction giving rise to these various effects is of the same nature. A graphical method for separating the resistance minimum from the total resistivity, in the presence of a resistance maximum produced by magnetic ordering in the Zn-Mn system, is presented

Pleasure and the Control of Food Intake: An Embodied Cognition Approach to Consumer Self‐Regulation

Consumers try to avoid temptation when exposed to appetizing foods by diverting their attention away from their senses (e.g., sight, smell, mouthfeel) and bodily states (e.g., state of arousal, salivation) in order to focus on their longer term goals (e.g., eating healthily, achieving an ideal body weight). However, when not including sensations in their decision‐making processes, consumers risk depleting their self‐regulatory resources, potentially leading to unhealthy food choices. Conversely, based on the concept of “embodied self‐regulation,” the suggestion is made that considering bodily states may help consumers regulate their food choices more effectively. A new model is proposed that facilitates understanding observed consumer behavior and the success or failure of self‐control in food intake. It is argued that bodily states and sensory information should be considered when modeling consumer behavior and developing health‐related advocacy and communication campaigns. The model proposed here leads to new perspectives on consumer consumption behavior and health policy research and strategies

Transforming a methodological dilemma into a rewarding research opportunity

This article focuses on an investigation of English as a Foreign Language (EFL) teacher (de)motivation in Spain which underwent a methodological transformation from mixed methods to a qualitative approach. Unexpected statistical results from the questionnaire in the piloting phase led to the creation of interview prompts, a dynamic data collection instrument based on reliable items from the questionnaire which was disregarded from the main study at a later stage. The interview prompts provided a card-based data collection method which engaged participants in reflective and challenging tasks. This paper will discuss an unsettling challenge in the research process, how it was seized and the positive outcome which emerged from this unpredicted pitfall. A research breakdown welcomed a methodological turn enabled by the researcher’s reflection on the research dilemma. Authors are encouraged to defy and embrace research obstacles while learning from them and sharing the solutions with the research community

Magnetotransport of CeRhIn5

We report measurements of the temperature-dependent anisotropic resistivity and in-plane magnetoresistance on single crystals of the tetragonal heavy-fermion antiferromagnet (TN = 3.8 K) CeRhIn5. The measurements are reported in the temperature range 1.4 K to 300 K and in magnetic fields to 18 tesla. The resistivity is moderately anisotropic, with a room-temperature c-axis to in-plane resistivity ratio rho_c/rho_a(300 K) = 1.7. rho(T) measurements on the non-magnetic analog LaRhIn5 indicate that the anisotropy in the CeRhIn5 resistivity stems predominately from anisotropy in Kondo-derived magnetic scattering. In the magnetically ordered regime an applied field H reduces TN only slightly due to the small ordered moment (0.37mu_B) and magnetic anisotropy. The magnetoresistance (MR) below TN is positive and varies linearly with H. In the paramagnetic state a positive MR is present below 7.5 K, while a high-field negative contribution is evident at higher temperatures. The positive contribution decreases in magnitude with increasing temperature. Above 40 K the positive contribution is no longer observable, and the MR is negative. The low-T positive MR results from interactions with the Kondo-coherent state, while the high-T negative MR stems from single-impurity effects. The H and T-dependent magnetotransport reflects the magnetic anisotropy and Kondo interactions at play in CeRhIn5.Comment: submitted to Physical Review

Using clickers in a large business class: examining use behavior and satisfaction

YesAs more and more institutions are integrating new technologies (e.g., audience response systems such as clickers) into their teaching and learning systems, it is becoming increasingly necessary to have a detailed understanding of the underlying mechanisms of these advanced technologies and their outcomes on student learning perceptions. We proposed a conceptual model based on the technology acceptance model to understand students’ use behavior and satisfaction with clickers. The valid response from 138 second-year business students of Digital Marketing module taught in a British university, where clickers are extensively used in the teaching and learning process, made the basis for data analysis. The results provided a strong support for the proposed model with a reasonably adequate variance (i.e., adjusted R2) of 67% on behavioral intentions and sufficiently high variance on use behavior (i.e., 86%) and user satisfaction (i.e., 89%)

A review of literature on the use of clickers in the business and management discipline

YesClassroom response systems (clickers), in their various forms, are widely used across disciplines, demonstrating effectiveness across a range of different educational settings. However, only a few literature reviews on this technology have been undertaken in general, and no review has yet been performed on this topic in the business and management context. Realising the existing research gap, this article reviews 33 clicker-related studies from the business and management discipline that are largely focused on student perceptions and outcomes. The purpose of this paper is to provide a critical and balanced review of articles from the business and management discipline on various themes such as learner's engagement, performance, learning, participation, satisfaction, feedback, attendance, enjoyability, motivation, and interactivity, to name a few. The review also provides a brief account of lessons learned from the literature published in other disciplines and recommendations provided by studies from the business and management discipline