Tracking the identity of moving words: Stimulus complexity and familiarity affects tracking accuracy

In two experiments, participants tracked the identity and location of moving words. The task bears resemblance to one performed by air traffic controllers who track multiple moving aircraft, where they are identified with relatively complex alphanumeric call signs. In Experiment 1, stimulus familiarity was manipulated by comparing the tracking of familiar words and pseudowords. In Experiment 2, also stimulus complexity was varied by having the participants track short and long words. Stimulus complexity affected tracking: Short words were easier to track than long words. Moreover, familiarity of identity affected tracking of short words (short familiar words were easier to track than short pseudo-words) but not of long words. The results are interpreted within the framework of the model of multiple identity tracking model. Mathematical simulations suggest that observers may not have enough time for full identification of complex identities in a dynamic situation. Practical implications of the results for air traffic control are discussed.     

Correlating the internal length in strain gradient plasticity theory with the microstructure of material

The internal length is the governing parameter in strain gradient theories which among other things have been used successfully to interpret size effects at the microscale. Physically, the internal length is supposed to be related with the microstructure of the material and evolves during the deformation. Based on Taylor hardening law, we propose a power-law relationship to describe the evolution of the variable internal length with strain. Then, the classical Fleck–Hutchinson strain gradient theory is extended with a strain-dependent internal length, and the generalized Fleck–Hutchinson theory is confirmed here, by comparing our model predictions to recent experimental data on tension and torsion of thin wires with varying diameter and grain size. Our work suggests that the internal length is a configuration-dependent parameter, closely related to dislocation characteristics and grain size, as well as sample geometry when this affects either the underlying microstructure or the ductility of the material.     

Mentoring Program Enhancements Supporting Effective Mentoring of Children of Incarcerated Parents

Children of incarcerated parents (COIP) are at risk for a range of negative outcomes; however, participating in a mentoring relationship can be a promising intervention for these youth. This study examined the impact of mentoring and mentoring program enhancements on COIP. Secondary data analyses were conducted on an archival database consisting of 70,729 matches from 216 Big Brothers Big Sisters (BBBS) local agencies to establish the differential effects of mentoring on COIP. A subset of 45 BBBS agencies, representing 25,252 matches, participated in a telephone interview about program enhancements for better serving COIP. Results revealed that enhanced program practices, including having specific program goals, providing specialized mentor training, and receiving additional funding resulted in better outcomes for COIP matches. Specifically, specialized mentor training and receiving additional funding for serving matches containing COIP were associated with longer and stronger matches. Having specific goals for serving COIP was associated with higher educational expectations in COIP. Results are discussed in terms of benefits of a relationship‐based intervention for addressing the needs of COIP and suggestions for program improvements when mentoring programs are serving this unique population of youth.     

On the length scale of cyclic strain localization in fine-grained copper films

Fine-grained copper films on a flexible substrate were cyclically deformed under constant strain range control. It was found that cyclic dislocation plasticity through individual dislocation glide is still dominant at the submicrometer scale, while the ability of irreversible slip of dislocations gradually decreases and the damage was changed from extrusion-induced localization to cracking along grain boundary. Statistical evaluation of the mean spacing between slip bands and/or lines leads to a critical scale (～28 nm) below which dislocation-controlled cyclic strain localization would be shut down.     

Special issue preamble: Digit ratio (2D:4D) and individual differences research

The sexually differentiated second-to-fourth digit ratio (2D:4D) is currently frequently utilized in individual differences research as a putative indicator of the masculinizing brain organization effects of prenatal testosterone. This preamble introduces the journal special issue on this theme, entitled “Digit ratio (2D:4D) and individual differences research”. Notes regarding the background, history, and recent progress of 2D:4D research are provided, and the background of the special issue and the contents of its 11 research articles are briefly summarized.     

实施单病种临床路径缩短患者平均住院日

为研究单病种临床路径应用效果,对宫颈癌患者39例、输卵管妊娠患者29例实施,临床路径。结果显示,手术并发症发生率降低,平均住院日和住院费用、药品费、药占比均下降,并具有统计学意义（P〈0．05）。因此,应用单病种临床路径,能降低患者住院日和费用、提高医护工作效率、增加医院竞争力。     

Gait symmetric adaptation: Comparing effects of implicit visual distortion versus split-belt treadmill on aftereffects of adapted step length symmetry

Understanding gait adaptation is essential for rehabilitation, and visual feedback can be used during gait rehabilitation to develop effective gait training. We have previously shown that subjects can adapt spatial aspects of walking to an implicitly imposed distortion of visual feedback of step length. To further investigate the storage benefit of an implicit process engaged in visual feedback distortion, we compared the robustness of aftereffects acquired by visual feedback distortion, versus split-belt treadmill walking. For the visual distortion trial, we implicitly distorted the visual representation of subjects’ gait symmetry, whereas for the split-belt trial, the speed ratio of the two belts was gradually adjusted without visual feedback. After adaptation, the visual feedback or the split-belt perturbation was removed while subjects continued walking, and aftereffects of preserved asymmetric pattern were assessed. We found that subjects trained with visual distortion trial retained aftereffects longest. In response to the larger speed ratio of split-belt walking, the subjects showed an increase in the size of aftereffects compared to the smaller speed ratio, but it steeply decreased over time in all the speed ratios tested. In contrast, the visual distortion group showed much slower decreasing rate of aftereffects, which was evidence of longer storage of an adapted gait pattern. Visual distortion adaptation may involve the interaction and integration of the change in motor strategy and implicit process in sensorimotor adaptation. Although it should be clarified more clearly through further studies, the findings of this study suggest that gait control employs distinct adaptive processes during the visual distortion and split-belt walking and also the level of reliance of an implicit process may be greater in the visual distortion adaptation than the split-belt walking adaptation.     

Tool selectivity in a non-primate,the New Caledonian crow (Corvus moneduloides)

We present an experiment showing that New Caledonian crows are able to choose tools of the appropriate size for a novel task, without trial-and-error learning. This species is almost unique amongst all animal species (together with a few primates) in the degree of use and manufacture of polymorphic tools in the wild. However, until now, the flexibility of their tool use has not been tested. Flexibility, including the ability to select an appropriate tool for a task, is considered to be a hallmark of complex cognitive adaptations for tool use. In experiment 1, we tested the ability of two captive birds (one male, one female), to select a stick (from a range of lengths provided) matching the distance to food placed in a horizontal transparent pipe. Both birds chose tools matching the distance to their target significantly more often than would be expected by chance. In experiment 2, we used a similar task, but with the tools placed out of sight of the food pipe, such that the birds had to remember the distance of the food before selecting a tool. The task was completed only by the male, who chose a tool of sufficient length significantly more often than chance but did not show a preference for a matching length. Electronic Publication     

Effect of stride length on overarm throwing delivery: Part II: An angular momentum response

This is the second component of a two-part series investigating 3D momentum profiles specific to overhand throwing, where altering stride reportedly influences throwing mechanics resulting in significantly different physiologic outcomes and linear momentum profiles. Using a randomized cross-over design, nineteen pitchers (15 collegiate and 4 high school) were assigned to pitch two simulated 80-pitch games at ±25% of their desired stride length. An 8-camera motion capture system (240 Hz) integrated with two force plates (960 Hz) and radar gun tracked each overhand throw. Segmental angular momentums were summed yielding throwing arm and total body momentums, from which compensation ratio’s (relative contribution between the two) were derived. Pairwise comparisons at hallmark events and phases identified significantly different angular momentum profiles, in particular total body, throwing arm, and momentum compensation ratios (P ⩽ 0.05) as a result of manipulating stride length. Sagittal, frontal, and transverse angular momentums were affected by stride length changes. Transverse magnitudes showed greatest effects for total body, throwing arm, and momentum compensation ratios. Since the trunk is the main contributor to linear and angular momentum, longer strides appear to better regulate transverse trunk momentum in double support, whereas shorter strides show increased momentum prior to throwing arm acceleration.