Part 4: Human Nature Theories of Motivation

At the turn of the 20th century, Frederick Taylors’ Scientific Management Theory dominated the industrial landscape. Managers focused on the best, most efficient ways to accomplish tasks, and viewed workers as replaceable cogs in a machine. But a series of experiments at a factory outside of Chicago led to a new perspective of management and motivation, one that focused on people. This approach, developed by Elton Mayo, established Human Relations Theory and laid the groundwork for future human-nature models to follow, including the Myers-Briggs Type Indicator, Motivation 3.0, and the Golden Circle.https://stars.library.ucf.edu/motivationforpublicservants/1003/thumbnail.jp

AN ASSAY OF GRAFT-HOST INTERACTIONS ACROSS STRONG AND WEAK HISTOCOMPATIBILITY BARRIERS IN MICE

1. A new assay of graft-host interactions has been presented. It consists of the early finding of liver infiltrates in responsive and unresponsive homologous recipients 1 to 3 days after the intravenous injection of competent lymphoid tissue in the mouse. 2. Evidence is presented that infiltrates are of donor origin, and are influenced by a homologous antigenic environment. They can be quantitatively increased by preimmunization of donor to recipient and decreased by preimmunization of recipient to donor. Furthermore, they are present in lethally x-irradiated or neonatally thymectomized unresponsive recipients after intravenous injection of competent homologous spleen cells. 3. Splenomegaly, which also occurs in this early period, is a product of both donor and host-specific immune reactivity together with a small non-specific component of host reactivity. 4. A comparison, of the responsiveness of lymphoid tissue from different strains to the same transplantation antigens is presented, together with the observation of differences in the reactivity of reciprocal donor-recipient injection combinations to each other. 5. Graft-host interactions with this model can be demonstrated in donor-host strain combinations isogenic at the H-2 locus without preimmunization of the donor. Differences in reactivity of reciprocal donor-recipient combinations of lymphoid tissue injections to each other can be detected in this group as well as in the groups differing at the strong H-2 locus

Influence of Duration of Homograft on Humoral Responses in Man

Elevated titers of natural antibodies have been demonstrated in the sera of patients following transplantation. These humoral responses were thought to be associated with rejection. This concept was challenged by investigators whose studies associated these responses with infection or with injection of heterologous serum. Nevertheless, the possible prognostic significance of these relatively simple tests has continued to evoke interest. This study was undertaken to compare the humoral responses in three different groups of patients with organ transplants in order to evaluate the influence of duration of the homograft and the attendant immunosuppression

Soleus stretch reflex during cycling

The modulation and strength of the human soleus short latency stretch reflex was investigated by mechanically perturbing the ankle during an unconstrained pedaling task. Eight subjects pedaled at 60 rpm against a preload of 10 Nm. A torque pulse was applied to the crank at various positions during the crank cycle, producing ankle dorsiflexion perturbations of similar trajectory. The stretch reflex was greatest during the power phase of the crank cycle and was decreased to the level of background EMG during recovery. Matched perturbations were induced under static conditions at the same crank angle and background soleus EMG as recorded during the power phase of active pedaling. The magnitude of the stretch reflex was not statistically different from that during the static condition throughout the power phase of the movement. The results of this study indicate that the stretch reflex is not depressed during active cycling as has been shown with the H-reflex. This lack of depression may reflect a decreased susceptibility of the stretch reflex to inhibition, possibly originating from presynaptic mechanisms

Energy efficient hopping with Hill-type muscle properties on segmented legs.

The intrinsic muscular properties of biological muscles are the main source of stabilization during locomotion, and superior biological performance is obtained with low energy costs. Man-made actuators struggle to reach the same energy efficiency seen in biological muscles. Here, we compare muscle properties within a one-dimensional and a two-segmented hopping leg. Different force-length-velocity relations (constant, linear, and Hill) were adopted for these two proposed models, and the stable maximum hopping heights from both cases were used to estimate the cost of hopping. We then performed a fine-grained analysis during landing and takeoff of the best performing cases, and concluded that the force-velocity Hill-type model is, at maximum hopping height, the most efficient for both linear and segmented models. While hopping at the same height the force-velocity Hill-type relation outperformed the linear relation as well. Finally, knee angles between 60° and 90° presented a lower energy expenditure than other morphologies for both Hill-type and constant relations during maximum hopping height. This work compares different muscular properties in terms of energy efficiency within different geometries, and these results can be applied to decrease energy costs of current actuators and robots during locomotion.RoboSoft—Coordination Action for Soft RoboticsThis is the author accepted manuscript. The final version is available from the Institute of Physics via http://dx.doi.org/10.1088/1748-3190/11/3/03600

Features in geometric receiver shapes modelling bat-like directivity patterns

The directional properties of bat ears as receivers is a current area of interest in ultrasound research. This paper presents a new approach to analyse the relationship between morphological features and acoustical properties of the external ear of bat species. The beam pattern of Rousettus leschenaultii’s right ear is measured and compared to that of receiver structures whose design is inspired by the bat ear itself and made of appropriate geometric shapes. The regular shape of these receivers makes it possible to control the key reception parameters and thus to understand the effect on the associated beam pattern of the parameters themselves. Measurements show one receiver structure has a beam pattern very similar to that of R. leschenaultii’s ear, thus explaining the function of individual parts constituting its ear. As it is applicable to all bat species, this approach can provide a useful tool to investigate acoustics in bats, and possibly other mammals

Reynolds number influences in aeronautics

Reynolds number, a measure of the ratio of inertia to viscous forces, is a fundamental similarity parameter for fluid flows and therefore, would be expected to have a major influence in aerodynamics and aeronautics. Reynolds number influences are generally large, but monatomic, for attached laminar (continuum) flow; however, laminar flows are easily separated, inducing even stronger, non-monatomic, Reynolds number sensitivities. Probably the strongest Reynolds number influences occur in connection with transitional flow behavior. Transition can take place over a tremendous Reynolds number range, from the order of 20 x 10(exp 3) for 2-D free shear layers up to the order of 100 x 10(exp 6) for hypersonic boundary layers. This variability in transition behavior is especially important for complex configurations where various vehicle and flow field elements can undergo transition at various Reynolds numbers, causing often surprising changes in aerodynamics characteristics over wide ranges in Reynolds number. This is further compounded by the vast parameterization associated with transition, in that any parameter which influences mean viscous flow development (e.g., pressure gradient, flow curvature, wall temperature, Mach number, sweep, roughness, flow chemistry, shock interactions, etc.), and incident disturbance fields (acoustics, vorticity, particulates, temperature spottiness, even electro static discharges) can alter transition locations to first order. The usual method of dealing with the transition problem is to trip the flow in the generally lower Reynolds number wind tunnel to simulate the flight turbulent behavior. However, this is not wholly satisfactory as it results in incorrectly scaled viscous region thicknesses and cannot be utilized at all for applications such as turbine blades and helicopter rotors, nacelles, leading edge and nose regions, and High Altitude Long Endurance and hypersonic airbreathers where the transitional flow is an innately critical portion of the problem

Microwave Components with MEMS Switches

RF MEMS switches with metal-metal contacts are being developed for microwave applications where broadband, high linearity performance is required. These switches provide less than 0.2 dB insertion loss through 40 GHz. This paper describes the integration of these switches into selected microwave components such as reconfigurable antenna elements, tunable filters, switched delay lines, and SPDT switches. Microwave and millimeter wave measured results from these circuits are presented