Miracle-dz/UniFAR-FTUs huggingface dataset:
When Insight Just Won't Come: The Failure of Visual Cues in the Nine-Dot Problem

The nine-dot problem is a classic in the field of human problem solving. Cognitive accounts of the problem's difficulty have been criticized on the grounds that the experimental methods on which they rely for support involve a qualitative change to the task requirements of the problem. The three experiments reported here utilize visual and visual-procedural hints to examine the notion that its difficulty is rooted in a mismatch between problem shape and solution shape. Experiment 1 demonstrated that a perceptual cue to the shape of the solution in the form of shading gave rise to only minimal improvements in performance; an additional hint about the relevance of the shading gave rise to modest, but not statistically significant, improvements. Experiment 2 replicated these findings against an additional control condition in which a solely verbal hint to violate the perceptual boundary of the problem shape was given. Furthermore, when both the verbal and visual hints were provided, performance improved only slightly. Experiment 3 provided participants with experience in producing the shape of the correct solution in problem variants closely related to the nine-dot problem. Performance on the transfer task, the basic nine-dot problem, remained at floor, however. These data suggest that visual constraint relaxation is unlikely to be the sole process by which the insight required to find a solution is achieved. The results are interpreted in terms of a previously proposed computational model of performance.
Professional Learning in the Workplace : A Case in Study in Higher Education.

With the aim of contributing to understanding of learning in the workplace, this thesis uses a case study approach to explore the learning of a newly-formed community of practice in the complex environment of higher education. Social theories of learning, based on a paradigm where learning is part of a social activity, have emerged to explain how individuals and groups develop knowledge in the workplace. Whilst studies to date have focussed on established communities of practice, very little work has examined how a new group, with no established experts or ways of working, learns in the workplace. Analysis of interview data from a newly-formed group of eleven learning and teaching co-ordinators revealed a series of practice clusters in which participants appear to engage. Organisationally-derived practice clusters, categorised as systemic, project and knowledge construction practices, relate to tasks identified on the job description. Data analysis also revealed four clusters of agency-derived practice: navigation practices, legitimation practices, affirmation practices and motivation practices. As participants engage in both organisationally-derived and agency-derived practice clusters, they draw upon, and in turn develop, resources which I have grouped into resource clusters comprising knowledge resources and enabling resources, specifically support, guidance, feedback and confidence. The contribution of the research is its focus on the learning of a newly-formed community of practice. Specifically, I propose that to understand the learning of such a community, it is useful to focus on the complex dynamic between the practice clusters in which the members engage and the resource clusters developed and drawn upon. The influence of both individual and organisational factors should be considered, and whilst neither should be given priority, it is likely that the individual will be more proactive, particularly in seeking out support, than a member of an established community of practice.
An analytic approach to moving obstacle avoidance using an artificial potential field

This paper proposes a unified method for moving obstacle avoidance of a robot. The method incorporates the artificial potential field (APF) concept into view-time based motion planning where the driving force is generated at every interval of the view-time. The view-time is defined as the time set from one sampling time instant to the next. The velocity and acceleration of the moving obstacle is assumed to be monitored or priorly known at each sampling time. At each sampling time, an accessible region that will be swept by the obstacle in the next view-time is predicted from the velocity, acceleration, and dynamic constraints of the obstacle. Then, an APF which exerts repulsive force on the robot is constructed around the accessible region. During the view-time, the force induced by the artificial potential field drives the robot away from the accessible obstacle trajectories in real-time. The dynamic constraints of the robot are also considered. Application of the described procedure at each successive sampling time from the initial to final location yields the collision-free trajectory for moving obstacle avoidance.
Non‐trophic impacts from white sharks complicate population recovery for sea otters

Abstract Complex interactions between protected populations may challenge the recovery of whole ecosystems. In California, white sharks (Carcharodon carcharias) mistargeting southern sea otters (Enhydra lutris nereis) are an emergent impact to sea otter recovery, inhibiting the broader ecosystem restoration sea otters might provide. Here, we integrate and analyze tracking and stranding data to compare the phenology of interactions between white sharks and their targeted prey (elephant seals, Mirounga angustirostris) with those of mistargeted prey (sea otters, humans). Pronounced seasonal peaks in shark bites to otters and humans overlap in the late boreal summer, immediately before the annual adult white shark migration to elephant seal rookeries. From 1997 to 2017, the seasonal period when sharks bite otters expanded from 2 to 8 months of the year and occurred primarily in regions where kelp cover declined. Immature and male otters, demographics most associated with range expansion, were disproportionately impacted. While sea otters are understood to play a keystone role in kelp forests, recent ecosystem shifts are revealing unprecedented bottom‐up and top‐down interactions. Such shifts challenge ecosystem management programs that rely on static models of species interactions.
Control of the propagation of dendritic low‐threshold Ca2+ spikes in Purkinje cells from rat cerebellar slice cultures

To investigate the ionic mechanisms controlling the dendrosomatic propagation of low‐threshold Ca2+ spikes (LTS) in Purkinje cells (PCs), somatically evoked discharges of action potentials (APs) were recorded under current‐clamp conditions. The whole‐cell configuration of the patch‐clamp method was used in PCs from rat cerebellar slice cultures. Full blockade of the P/Q‐type Ca2+ current revealed slow but transient depolarizations associated with bursts of fast Na+ APs. These can occur as a single isolated event at the onset of current injection, or repetitively (i.e. a slow complex burst). The initial transient depolarization was identified as an LTS Blockade of P/Q‐type Ca2+ channels increased the likelihood of recording Ca2+ spikes at the soma by promoting dendrosomatic propagation. Slow rhythmic depolarizations shared several properties with the LTS (kinetics, activation/inactivation, calcium dependency and dendritic origin), suggesting that they correspond to repetitively activated dendritic LTS, which reach the soma when P/Q channels are blocked. Somatic LTS and slow complex burst activity were also induced by K+ channel blockers such as TEA (2.5 × 10−4m) charybdotoxin (CTX, 10−5m), rIberiotoxin (10−7m), and 4‐aminopyridine (4‐AP, 10−3m), but not by apamin (10−4m). In the presence of 4‐AP, slow complex burst activity occurred even at hyperpolarized potentials (−80 mV). In conclusion, we suggest that the propagation of dendritic LTS is controlled directly by 4‐AP‐sensitive K+ channels, and indirectly modulated by activation of calcium‐activated K+ (BK) channels via P/Q‐mediated Ca2+ entry. The slow complex burst resembles strikingly the complex spike elicited by climbing fibre stimulation, and we therefore propose, as a hypothesis, that dendrosomatic propagation of the LTS could underlie the complex spike.
Magnetic Skyrmion-Based Neural Recording System Design for Brain Machine Interface

Next-generation brain machine interface demand a high-channel-count neural recording system to wirelessly monitor activities of thousands of neurons. In order to achieve high-density neural recording, further development of single recording channel comprised of a neural amplifier front-end (AFE) and an analog-to-digit converter (ADC) is critical. Despite the great progress made in CMOS implementation of custom-designed neural recording system, hybrid limitations of increasing area and power consumption in line with Moore's law drove great demand for post-CMOS substitutes. Magnetic skyrmion with nano particle-like and non-volatile properties are of both fundamental and applied interests for future bio-inspired electronics. In this work, we propose a compact model including both AFE and ADC based on current-induced skyrmion motion. The proposed system achieved a power consumption of 0.63 pJ/channel with an area overhead of 0.14 μm2. The purpose of this work is to explore the feasibility of magnetic skyrmion for building large-scale, dense neuronal recording system which could pave a new way for future brain machine interface application.
Tryptophan Requirement of the Enterally Fed Term Infant in the First Month of Life

Objectives: Tryptophan not only is an amino acid essential to protein synthesis but also serves as a precursor in 2 important metabolic pathways: the serotonin and the kynurenine pathways. Tryptophan is related to sleeping patterns. The objective of the present study was to determine the tryptophan requirement of term infants using the indicator amino acid oxidation (IAAO) method with L-[1-13C]phenylalanine as the indicator. Methods: Enterally fed infants were randomly assigned to tryptophan intakes ranging from 0.5 to 73 mg · kg−1 · day−1 as part of an elemental diet. After 1-day adaptation to the test diet, [13C]bicarbonate and L-[1-13C]phenylalanine tracers were given enterally. Breath samples were collected at baseline and during isotopic plateaus. The mean tryptophan requirement was determined by using the biphasic linear regression crossover analysis on the fraction of 13CO2 recovery from L-[1-13C]phenylalanine oxidation (F13CO2). Data are presented as mean ± standard deviation. Results: A total of 30 term neonates (gestational age 39 ± 1 weeks) were studied at 9 ± 4 days. F13CO2 decreased until a tryptophan intake of 15 mg · kg−1 · day−1; additional increases in tryptophan intake did not affect F13CO2. Mean requirement was determined to be 15 mg · kg−1 · day−1. Conclusions: The mean tryptophan requirement for elemental formula-fed term infants is 15 mg · kg−1 · day−1. This requirement is lower than the present recommended intake of 29 mg · kg−1 · day−1, which is based on the average intake of a breastfed infant.
Treatment of major depression with psychotherapy or psychotherapy-pharmacotherapy combinations.

BACKGROUND Few reliable correlates of treatment response in depression have emerged despite nearly 40 years of research. We examined the correlates of recovery in a "mega-analysis," or meta-analysis of original data, of 595 patients with major depressive disorder enrolled in 6 standardized treatment protocols. METHODS All patients (mean age, 44 years; 31% male and 69% female) met criteria for nonbipolar, nonpsychotic primary major depressive disorder and were treated for 16 weeks with either cognitive behavior therapy or interpersonal psychotherapy alone (psychotherapy alone; n = 243) or interpersonal psychotherapy plus antidepressant pharmacotherapy (combined therapy; n = 352). The impact of treatment type, severity, study, and other covariates on recovery rates or time to recovery were examined by means of chi 2, log-rank tests, the Cox proportional hazards model, and sensitivity analyses. RESULTS Whereas combined therapy was not significantly more effective than psychotherapy alone in milder depressions, a highly significant advantage was observed in more severe recurrent depressions. Poorer outcomes were also observed in women and older patients, although these effects were dependent on inclusion of particular studies. CONCLUSIONS Mega-analysis is a powerful method for comparing the efficacy of treatments and examining correlates of response. Using this method, we found new evidence in support of the widespread clinical impression that combined therapy is superior to psychotherapy alone for treatment of more severe, recurrent depressions.
Modeling trans-spinal direct current stimulation for the modulation of the lumbar spinal motor pathways

Objective. Trans-spinal direct current stimulation (tsDCS) is a potential new technique for the treatment of spinal cord injury (SCI). TsDCS aims to facilitate plastic changes in the neural pathways of the spinal cord with a positive effect on SCI recovery. To establish tsDCS as a possible treatment option for SCI, it is essential to gain a better understanding of its cause and effects. We seek to understand the acute effect of tsDCS, including the generated electric field (EF) and its polarization effect on the spinal circuits, to determine a cellular target. We further ask how these findings can be interpreted to explain published experimental results. Approach. We use a realistic full body finite element volume conductor model to calculate the EF of a 2.5 mA direct current for three different electrode configurations. We apply the calculated electric field to realistic motoneuron models to investigate static changes in membrane resting potential. The results are combined with existing knowledge about the theoretical effect on a neuronal level and implemented into an existing lumbar spinal network model to simulate the resulting changes on a network level. Main results. Across electrode configurations, the maximum EF inside the spinal cord ranged from 0.47 V m−1 to 0.82 V m−1. Axon terminal polarization was identified to be the dominant cellular target. Also, differences in electrode placement have a large influence on axon terminal polarization. Comparison between the simulated acute effects and the electrophysiological long-term changes observed in human tsDCS studies suggest an inverse relationship between the two. Significance. We provide methods and knowledge for better understanding the effects of tsDCS and serve as a basis for a more targeted and optimized application of tsDCS.
Acute pancreatitis with gradient echo T2*-weighted magnetic resonance imaging.

BACKGROUND To study gradient recalled echo (GRE) T2*-weighted imaging (T2*WI) for normal pancreas and acute pancreatitis (AP). METHODS Fifty-one patients without any pancreatic disorders (control group) and 117 patients with AP were recruited. T2* values derived from T2*WI of the pancreas were measured for the two groups. The severity of AP was graded by the magnetic resonance severity index (MRSI) and the Acute Physiology and Chronic Healthy Evaluation II (APACHE II) scoring system. Logistic regression was used to analyze the relationship between the T2* values and AP severity. The usefulness of the T2* value for diagnosing AP and the relationship between the T2* values and the severity of AP were analyzed. RESULTS On GRE-T2*WI, the normal pancreas showed a well-marinated and consistently homogeneous isointensity. Edematous AP, as well as the non-necrotic area in necrotizing AP, showed ill-defined but homogeneous signal intensity. AP with pancreatic hemorrhage showed a decreased T2* value and a signal loss on the signal decay curve. The T2* value of pancreas in the AP group was higher than that of the control group (t=-8.20, P<0.05). The T2* value tended to increase along with the increase in MRSI scores but not with the APACHE II scores (P>0.05). AP was associated with a one standard deviation increment in the T2* value (OR =1.37; 95% CI: 1.216-1.532). CONCLUSIONS T2*WI demonstrates a few characteristics of the normal pancreas and AP, which could potentially be helpful for detecting hemorrhage, and contributes to diagnosing AP and its severity.
Nonlinear Modeling for a Water-Jet Propulsion USV: An Experimental Study

Although unmanned surface vehicles (USVs) have been extensively researched and applied to many typical scenarios, high-performance autonomous control is still an open problem. One of their major problem stems from the difficulty in constructing a sufficient accurate and sufficient simple control-oriented dynamics model. Owing to the highly complicated physical mechanisms of hydrodynamics, USV systems possess strong nonlinearities and coupling, which make it exceptionally difficult to develop an accurate model structure. In real applications, extensively existing uncertainties, such as external disturbances due to wind, wave, current, and measurement noise in the onboard sensor, will unavoidably influence identification precision with respect to the parameters in the USV's model. Thus, in this paper, a new kind of nonlinear modeling scheme—the active modeling enhanced quasi-linear parameter-varying (qLPV) model—is proposed for a water-jet propulsion USV system. First, a qLPV-structured model is derived by simplifying the real dynamics model, which has a simple quasi-linear structure and can approximate the nonlinearities of the hydrodynamics. Subsequently, a nonlinear version of the Kalman filter-based active modeling method is proposed to provide online estimates of the unstructured model to eliminate the errors due to the structure inaccuracy between the qLPV-structured model and the real system. Finally, the newly proposed modeling scheme is tested on a real USV system and its superiority is shown through comparisons to some other traditional modeling methods.
Two types of calcium channels in the somatic membrane of new‐born rat dorsal root ganglion neurones.

Ca2+ inward currents evoked by membrane depolarization have been studied by the intracellular dialysis technique in the somatic membrane of isolated dorsal root ganglion neurones of new‐born rats. In about 20% of the investigated cells a hump has been detected on the descending branch of the current‐voltage curve, indicating the presence of two populations of Ca2+ channels differing in their potential‐dependent characteristics. An initial less regular component of the Ca2+ current was activated at membrane potentials from ‐75 to ‐70 mV. Its amplitude reached 0.2‐0.9 nA at 14.6 mM‐extracellular Ca2+. The activation kinetics of this component could be approximated by the Hodgkin‐Huxley equation using the square of the m variable. tau m varied in the range from 8 to 1 ms at potentials between ‐60 and ‐25 mV ('fast' Ca2+ current). The second component of the Ca2+ current was activated at membrane depolarizations to between ‐55 and ‐50 mV. It could be recorded in all cells investigated and reached a maximum value of 1‐7 nA at the same extracellular Ca2+ concentration. This component decreased rapidly during cell dialysis with saline solutions. The decrease could be slowed down by cooling and accelerated by warming the extracellular solution. Intracellular introduction of 3',5'‐cAMP together with ATP and Mg2+ not only prevented the decrease but often restored the maximal current amplitude to its initial level. The activation kinetics of this component could also be approximated by a square function, tau m being in the range 16‐2.5 ms at membrane potentials between ‐20 and +3 mV ('slow' Ca2+ current). The fast Ca2+ current inactivated exponentially at sustained depolarizations in a potential‐dependent manner, tau h varying from 76 to 35 ms at potentials between ‐50 and ‐30 mV. The inactivation of the slow Ca2+ current studied in double‐pulse experiments was current‐dependent and developed very slowly (time constant of several hundreds of milliseconds). It slowed down even more at low temperature or after substitution of Ba2+ for Ca2+ in the extracellular solution. Both currents could also be carried by Ba2+ and Sr2+, although the ion‐selecting properties of the two types of channels showed quantitative differences. Specific blockers of Ca2+ channels (Co2+, Mn2+, Cd2+, Ni2+ or verapamil) exerted similar effects on them. The existence of metabolically dependent and metabolically independent Ca2+ channels in the neuronal membrane and their possible functional role are discussed.
Welfare Reform and the Work Support System

[© Brookings Institution] Although the sweeping welfare reform law of 1996 has received widespread attention in the media and among policymakers, the development of the nation's work support system, which is a vital complement to the 1996 reforms, has received far less attention. The work support system is a series of programs that provide benefits to poor and low-income working families. In popular parlance, they are programs that make work pay. The most important of these programs are the minimum wage, the Earned Income Tax Credit, the child tax credit, income supplement programs conducted by states, food stamps, health insurance, child support enforcement, and child care. A recent study by the Congressional Budget Office showed that numerous expansions of these programs since the mid-1980s have increased by a factor of more than eight the value of federal work support benefits now being paid to working families. Given the important role these programs play in maintaining work incentives, supplementing earned income so working families can provide a minimum living standard for their children, and helping families when unemployment hits, the maintenance and even expansion of these programs will be a major part of this year's welfare reauthorization debate in Congress. In this brief, we provide an overview of work support programs and examine the pros and cons of proposals to expand them.
Health care system changes and reported musculoskeletal disorders among registered nurses.

OBJECTIVES We evaluated the impact of health care system changes on nurses' health, and we studied reported musculoskeletal disorders associated with these changes. METHODS This cross-sectional study (n = 1163) defined a musculoskeletal disorder case as moderate pain that lasted at least 1 week or occurred monthly during the past year. Nurses were asked about changes in the health care system in the past year, and responses to 12 changes were summed and were categorized as low, moderate, or high changes. RESULTS When the changes were summed, the adjusted odds ratios for musculoskeletal disorders for more than 6 versus 0 to 1 changes were (1) neck: 4.45 (95% confidence interval [CI] = 1.97, 10.08), (2) shoulder: 2.63 (95% CI = 1.17, 5.91), and (3) back: 3.42 (95% CI = 1.61, 7.27). CONCLUSIONS The adverse impact on health caused by the changing health care system must be addressed to prevent further injuries among nurses.