Miracle-dz/UniFAR-FTUs huggingface dataset:
Transferring Skills at Solving Word Problems from Computing to Algebra Through Bootstrap

Many educators have tried to leverage computing or programming to help improve students' achievement in mathematics. However, several hopes of performance gains---particularly in algebra---have come up short. In part, these efforts fail to align the computing and mathematical concepts at the level of detail typically required to achieve transfer of learning. This paper describes Bootstrap, an early-programming curriculum that is designed to teach key algebra topics as students build their own videogames. We discuss the curriculum, explain how it aligns with algebra, and present initial data showing student performance gains on standard algebra problems after completing Bootstrap.
The dampening effect of employees’ future orientation on cyberloafing behaviors: the mediating role of self-control

Previous studies on reducing employees’ cyberloafing behaviors have primarily examined the external control factors but seldomly taken individual internal subjective factors into consideration. Future orientation, an important individual factor, is defined as the extent to which one plans for future time and considers future consequences of one’s current behavior. To explore further whether and how employees’ future orientation can dampen their cyberloafing behaviors, two studies were conducted to examine the relationship between employees’ future orientation and cyberloafing behaviors. The mediation effect of employees’ objective and subjective self-control between them was also examined. In Study 1, a set of questionnaires was completed, and the results revealed that the relationship between employees’ future orientation and cyberloafing behaviors was negative, and objective self-control mediated the relationship. Next, we conducted a priming experiment (Study 2) to examine the causal relationship and psychological mechanism between employees’ future orientation and cyberloafing behaviors. The results demonstrated that employees’ future-orientation dampened their attitudes and intentions to engage in cyberloafing, and subjective self-control mediated this dampening effect. Theoretical and practical implications of these findings are also discussed.
Priority rules govern the organization of traffic on foraging trails under crowding conditions in the leaf-cutting ant Atta colombica

SUMMARY Foraging in leaf-cutting ants is generally organized along well-defined recruitment trails supporting a bi-directional flow of outbound and nestbound individuals. This study attempts to reveal the priority rules governing the organization of traffic on these trails. Ants were forced to move on a narrow trail, allowing the passage of only two individuals at a time. In this condition, a desynchronization of inbound and outbound traffic was observed, involving the formation of alternating clusters of inbound and outbound ants. Most clusters of inbound ants were headed by laden ants followed by unladen ants. This occurred because inbound unladen ants did not attempt to overtake the laden ants in front of them. As unladen ants move on average faster than laden ants, these ants were thus forced to decrease their speed. By contrast, this decrease was counterbalanced by the fact that, by staying in a cluster instead of moving in isolation, inbound unladen ants limit the number of head-on encounters with outbound ants. Our analysis shows that the delay induced by these head-on encounters would actually be twice as high as the delay induced by the forced decrease in speed incurred by ants staying in a cluster. The cluster organization also promotes information transfer about the level of food availability by increasing the number of contacts between outbound and inbound laden ants, which could possibly stimulate these former to cut and retrieve leaf fragments when reaching the end of the trail.
Enteropathogenic Escherichia coli dephosphorylates and dissociates occludin from intestinal epithelial tight junctions

Enteropathogenic Escherichia coli (EPEC) increases tight junction permeability in part by phosphorylating the 20 kDa myosin light chain (MLC20) that induces cytoskeletal contraction. The impact of this enteric pathogen on specific tight junction (TJ) proteins has not been investigated. We examined the effect of EPEC infection on occludin localization and phosphorylation in intestinal epithelial cells. After infection by EPEC, a progressive shift of occludin from a primarily TJ‐associated domain to an intracellular compartment occurred, as demonstrated by immunofluorescent staining. A reverse in the ratio of phosphorylated to dephosphorylated occludin accompanied this morphological change. Eradication of EPEC with gentamicin resulted in the normalization of occludin localization and phosphorylation. The serine/threonine phosphatase inhibitor, calyculin A, prevented these events. The EPEC‐associated decrease in transepithelial electrical resistance, a measure of TJ barrier function, returned to baseline after gentamicin treatment. Non‐pathogenic E. coli, K‐12, did not induce these changes. Transformation of K‐12 with the pathogenicity island of EPEC, however, conferred the phenotype of wild‐type EPEC. Deletion of specific EPEC genes encoding proteins involved in EPEC type III secretion markedly attenuated these effects. These findings suggest that EPEC‐induced alterations in occludin contribute to the pathophysiology associated with this infection.
Outbreak of Francisella novicida bacteremia among inmates at a louisiana correctional facility.

BACKGROUND Francisella novicida is a rare cause of human illness despite its close genetic relationship to Francisella tularensis, the agent of tularemia. During April-July 2011, 3 inmates at a Louisiana correctional facility developed F. novicida bacteremia; 1 inmate died acutely. METHODS We interviewed surviving inmates; reviewed laboratory, medical, and housing records; and conducted an environmental investigation. Clinical and environmental samples were tested by culture, real-time polymerase chain reaction (PCR), and multigene sequencing. Isolates were typed by pulsed-field gel electrophoresis (PFGE). RESULTS Clinical isolates were identified as F. novicida based on sequence analyses of the 16S ribosomal RNA, pgm, and pdpD genes. PmeI PFGE patterns for the clinical isolates were indistinguishable. Source patients were aged 40-56 years, male, and African American, and all were immunocompromised. Two patients presented with signs of bacterial peritonitis; the third had pyomyositis of the thigh. The 3 inmates had no contact with one another; their only shared exposures were consumption of municipal water and of ice that was mass-produced at the prison in an unenclosed building. Swabs from one set of ice machines and associated ice scoops yielded evidence of F. novicida by PCR and sequencing. All other environmental specimens tested negative. CONCLUSIONS To our knowledge, this is the first reported common-source outbreak of F. novicida infections in humans. Epidemiological and laboratory evidence implicate contaminated ice as the likely vehicle of transmission; liver disease may be a predisposing factor. Clinicians, laboratorians, and public health officials should be aware of the potential for misidentification of F. novicida as F. tularensis.
Integrated lossy, near-lossless, and lossless compression of medical volumetric data

We propose an integrated, wavelet based, two-stage coding scheme for lossy, near-lossless and lossless compression of medical volumetric data. The method presented determines the bit-rate while encoding for the lossy layer and without any iteration. It is in the spirit of "lossy plus residual coding" and consists of a wavelet-based lossy layer followed by an arithmetic coding of the quantized residual to guarantee a given pixel-wise maximum error bound. We focus on the selection of the optimum bit rate for the lossy coder to achieve the minimum total (lossy plus residual) bit rate in the near-lossless and the lossless cases. We propose a simple and practical method to estimate online the optimal bit rate and provide a theoretical justification for it. Experimental results show that the proposed scheme provides improved, embedded lossy, and lossless performance competitive with the best results published so far in the literature, with an added feature of near-lossless coding.
Object contour tracking using level sets

High level vision tasks (recognition, understanding, etc.) for video processing require tracking of the complete contour of the objects. In general, objects undergo non-rigid deformations, which limit the applicability of using motion models (e.g. affine, projective) that impose rigidity constraints on the objects. In this paper, we propose a contour tracking algorithm for video captured using mobile cameras of different modalities. The proposed tracking algorithm uses Bayesian inference based on the probability density functions (PDFs) of texture and color features. These feature PDFs are fused in an independent opinion polling strategy, where the contribution of each feature is defined by its discrimination power. We formulate the evolution of the object contour as a variational calculus problem and solve the system using level sets. The associated energy functional combines region-based and boundary-based object segmentation approaches into one framework for object tracking in video, evaluated in the vicinity of the object contour. In this regard, it can be viewed as generalization of formerly proposed methods where the shortcomings of other methods (color, shape, gradient constraints, etc.) are overcome. The robustness of the proposed algorithm is demonstrated on real sequences.
Integrated measuring approach for the study of corrosion mechanisms

The study of the corrosion mechanisms which affect iron artifacts is the first fundamental step for developing tailored and long-lasting conservation procedures. Unfortunately, such mechanisms are connected not only to the composition of the corrosion product layer, but also to its porosity and microstructure. μ-Raman spectroscopy can be used to assess the composition of the corrosion products, but the effect of the layer porosity requires a different approach. This paper investigates the combined use of μ-Raman and Electrochemical Impedance Spectroscopy (EIS) for the characterization of some iron reinforcements of the Metz Cathedral (France), with the final goals of understanding the corrosion mechanism and having a reliable assessment of the artifact stability. In particular, the proposed measuring approach has proved to be able to give useful data on the electrochemical reactivity of the surface, on the presence of cracks and on the porosity degree of the corrosion product layers. After a series of laboratory tests to characterize the surface, the EIS measurements can be employed also in-situ for a noninvasive assessment of the artifact corrosion behavior. This way it is possible to conceive long-lasting monitoring campaigns, which would allow one to identify artifacts apparently well-preserved, but in danger of possible corrosion due to the porous nature of their corrosion layers and the presence of active electrochemical species in contact to the metallic surface.
A role for phosphoinositide 3-kinase in the completion of macropinocytosis and phagocytosis by macrophages

Phosphoinositide 3-kinase (PI 3-kinase) has been implicated in growth factor signal transduction and vesicular membrane traffic. It is thought to mediate the earliest steps leading from ligation of cell surface receptors to increased cell surface ruffling. We show here that inhibitors of PI 3-kinase inhibit endocytosis in macrophages, not by interfering with the initiation of the process but rather by preventing its completion. Consistent with earlier studies, the inhibitors wortmannin and LY294002 inhibited fluid-phase pinocytosis and Fc receptor-mediated phagocytosis, but they had little effect on the receptor-mediated endocytosis of diI-labeled, acetylated, low density lipoprotein. Large solute probes of endocytosis reported greater inhibition by wortmannin than smaller probes did, indicating that macropinocytosis was affected more than micropinocytosis. Since macropinocytosis and phagocytosis are actin-mediated processes, we expected that their inhibition by wortmannin resulted from deficient signaling from macrophage colony-stimulating factor (M-CSF) receptors or Fc receptors to the actin cytoskeleton. However, video microscopy showed cell surface ruffling in wortmannin-treated cells, and increased ruffling after addition of M-CSF or phorbol myristate acetate. Quantitative measurements of video data reported slightly diminished ruffling in wortmannin-treated cells. Remarkably, the ruffles that formed in wortmannin-treated macrophages all receded into the cytoplasm without closing into macropinosomes. Similarly, wortmannin and LY294002 did not inhibit the extension of actin-rich pseudopodia along IgG- opsonized sheep erythrocytes, but instead prevented them from closing into phagosomes. These findings indicate that PI 3-kinase is not necessary for receptor-mediated stimulation of pseudopod extension, but rather functions in the closure of macropinosomes and phagosomes into intracellular organelles.
Towards a discretely actuated steerable cannula for diagnostic and therapeutic procedures

We have designed, developed, and evaluated the performance of a multi-degree-of-freedom discretely actuated steerable cannula with shape-memory alloy (SMA) actuators. This will enable us to deliver diagnostic as well as therapeutic devices to the target location through the hollow inner core of the cannula. We propose to use SMAs to generate bending forces due to its small size and high power density. We annealed the SMA wires through a customized training process in an arc shape and mounted them at discrete locations on the outer surface of the cannula to enable joint motion. A pulse-width modulation (PWM)-based control scheme was implemented to control all SMA actuators simultaneously to enable multiple joint motion using a single power supply. The proposed controller was validated through an experiment inside gelatin to mimic the motion of the cannula inside a medium which requires a significant amount of force to move the joints of the cannula. Trajectory planning using a suitable metric and trajectory execution were successfully implemented. To demonstrate the delivery of a diagnostic tool through our cannula, we demonstrate that we can pass an optical coherence tomography probe through the cannula and perform in situ microscale imaging.
Dirithromycin disc susceptibility tests: interpretative criteria and quality control parameters.

Dirithromycin and its bioactive metabolite (erythromycylamine) were compared in vitro to erythromycin against 450 bacterial isolates. Dirithromycin and erythromycylamine did not differ in their in-vitro activity and the two compounds were additive when combined in equal proportions. Both compounds were active against erythromycin-susceptible bacteria but erythromycin was two to four times more potent on a weight-to-weight basis. Interpretive criteria for dirithromycin were not based on achievable blood concentrations since tissue concentrations may be 20-30 times greater than peak serum levels. Dirithromycin-susceptible strains were those with zones > or = 19 mm in diameter (15 micrograms dirithromycin disc) or MIC < or = 2.0 mg/L and resistance was defined as a zone < or = 15 mm or MIC > or = 8.0 mg/L. Interpretive criteria for testing Haemophilus influenzae on Haemophilus Test Medium (HTM) agar were not defined because of the drug's poor activity in the test system used. Two multi-laboratory studies were also undertaken, one to define quality control limits for disc diffusion tests and the other to define broth microdilution MIC control limits for tests with dirithromycin.
Progressive dehydration causes a progressive decline in basketball skill performance.

PURPOSE To determine the effect of 1, 2, 3, and 4% dehydration (DEH) versus euhydration (EUH) on basketball performance in adult male players. METHODS Seventeen 17- to 28-yr-old male basketball players completed 3 h of interval treadmill walking (40 degrees C and 20% relative humidity) with or without fluid replacement. Subjects completed six trials in random order: 1) EUH with a carbohydrate-electrolyte solution (CES), 2) EUH control (flavored water with 0% carbohydrate and 18 mM sodium), 3) 1% DEH, 4) 2% DEH, 5) 3% DEH, and 6) 4% DEH. After a 70-min recovery period, subjects performed a sequence of continuous basketball drills designed to simulate a fast-paced game. Measures of overall skill performance during the 80-min game included 1) total time to complete basketball-specific movement drills (sprinting, defensive slides, sprinting-defensive slides combination, and repetitive jumping drills) and 2) total number of shots (foul-line and baseline jump shots, layups, three-point, 15-ft, free throws) made per game. RESULTS Performance during all timed and shooting drills declined progressively as % DEH increased. Total time to complete basketball-specific movement drills was slower (1%: + 7 +/- 6; 2%: + 20 +/- 5 (P < 0.05); 3%: + 26 +/- 7 (P < 0.005); 4%: + 57 +/- 9 (P < 0.0001) s), and fewer shots were made during DEH versus EUH control (1%: -5 +/- 1; 2%: -6 +/- 2 (P < 0.05); 3%: -8 +/- 2 (P < 0.005); 4%: -10 +/- 1 (P < 0.0001) shots made). There were no significant differences in performance between CES and EUH control. CONCLUSION Basketball players experienced a progressive deterioration in performance as DEH progressed from 1 to 4%. The threshold, or % DEH at which the performance decrement reached statistical significance, was 2% for combined timed and shooting drills.
Synthesis of TiO2 – Water Nanofluids for its Viscosity and Dispersion Stability Study

In the present research work, an anatase structure titanium dioxide nanoparticle was synthesized by hydrolysis of titanium isopropoxide in the presence and absence of ultrasonication. The resultant product suspension was peptized for getting narrow size distribution. The synthesized nanoparticles are used for preparation of nanofluids with different volume percent loading of nanoparticles in water ranging from 1% to 5%. The characterization of particles was carried out by TEM, XRD. Our result shows that the use of ultrasonic technique has a significant effect on the homogeneity and then size of TiO2 nanoparticles. Viscosity of nanofluids was demonstrated with rheometer (TA instruments). Viscosity results confirmed Newtonian behavior of nanofluids and showing increasing trends with addition of nanoparticles in base fluids. The dispersion of nanoparticles in nanofluids is studied with unique method of UV visible spectrophotometer, which confirm good dispersion stability prepared nanofluid of 50 hrs.
Effects of red pepper on appetite and energy intake

Two studies were conducted to investigate the effects of red pepper (capsaicin) on feeding behaviour and energy intake. In the first study, the effects of dietary red pepper added to high-fat (HF) and high-carbohydrate (HC) meals on subsequent energy and macronutrient intakes were examined in thirteen Japanese female subjects. After the ingestion of a standardized dinner on the previous evening, the subjects ate an experimental breakfast (1883 kJ) of one of the following four types: (1) HF; (2) HF and red pepper (10 g); (3) HC; (4) HC and red pepper. Ad libitum energy and macronutrient intakes were measured at lunch-time. The HC breakfast significantly reduced the desire to eat and hunger after breakfast. The addition of red pepper to the HC breakfast also significantly decreased the desire to eat and hunger before lunch. Differences in diet composition at breakfast time did not affect energy and macronutrient intakes at lunch-time. However, the addition of red pepper to the breakfast significantly decreased protein and fat intakes at lunch-time. In Study 2, the effects of a red-pepper appetizer on subsequent energy and macronutrient intakes were examined in ten Caucasian male subjects. After ingesting a standardized breakfast, the subjects took an experimental appetizer (644 kJ) at lunch-time of one of the following two types: (1) mixed diet and appetizer; (2) mixed diet and red-pepper (6 g) appetizer. The addition of red pepper to the appetizer significantly reduced the cumulative ad libitum energy and carbohydrate intakes during the rest of the lunch and in the snack served several hours later. Moreover, the power spectral analysis of heart rate revealed that this effect of red pepper was associated with an increase in the ratio sympathetic: parasympathetic nervous system activity. These results indicate that the ingestion of red pepper decreases appetite and subsequent protein and fat intakes in Japanese females and energy intake in Caucasian males. Moreover, this effect might be related to an increase in sympathetic nervous system activity in Caucasian males.
Biological activity of bacteriophage ghosts and "take-over" of host functions by bacteriophage.

INTRODUCTION. 344 METHODS UNIQUE TO THE STUDY OF GHOSTS. 345 Preparation of Ghosts. 345 Assay of Ghosts . 345 Purification of Ghosts. 346 Adsorption of Ghosts. 347 Antigenicity of Ghosts . 347 Killer versus Nonkiller Ghosts. 347 BIOLOGICAL ACTIVITIES OF GHOSTS. 347 Inhibition of Colony Formation. 347 Cell Lysis . 348 Superinfection Inhibition. 349 Energy Metabolism in Ghost-Infected Cells. 349 Inhibition of Host Macromolecular Syntheses. 350 Inhibition of Colicin Activity. 351 Effect of Chloramphenicol on Ghost Infection. 352 What Substructures Cause Killing? 352 INHIBITION OF HOST SYNTHESES AFTER PHAGE INFECTION. 352 Kinetics of Inhibition. 352 Is the Inhibition Due to Breakdown of the Host Chromosome? 353 Is Protein Synthesis Necessary? 353 CELL SURFACE CHANGES DURING PHAGE AND GHOST INFECTION. 354 Leakage of Metabolites During Phage Infection. 354 Leakage of Metabolites During Ghost Infection. 355 Effect of Mg+. 356 Transport in Phage and Ghost Infection. 356 Role of Lysozyme. 357 Other Membrane-Associated Phenomena in Phage Infection. 357 A WORD ABOUT BACTERIOCINS . 357 SUMMARY AND CONCLUSIONS. 358 LITERATURE CITED. 360
Scaling measurement experiments to planet-scale: ethical, regulatory and cultural considerations

Conducting planet-scale mobility experiments and measurements is of great interest to network researchers for building the next generation of wireless networking technologies, or for studying inter-disciplinary problems in complex networks. There are many technical challenges that need to be addressed before such experiments can take place. But at the same time, there are many non-technical issues that need to be tackled in order to preserve the welfare of participants in these studies. While some of these issues have been addressed in previous small-scale studies, they become increasingly complex when differences between countries need to be taken into account. This position paper highlights some of these issues and argues that they need to be addressed before planet-scale measurement experiments can be conducted. We discuss ethical, regulatory, cultural and privacy issues, and consider how to design measurement systems that will scale up to planet-wide experiments. We motivate our approach by discussing work in measurement of mobile and online social networks.