Miracle-dz/UniFAR-FTUs huggingface dataset:
THINKING THROUGH THREE WORLDS OF MATHEMATICS

David TallUniversity of Warwick CV4 7AL, UK The major idea in this paper is the formulation of a theory of three distinct but interrelated worlds of mathematical thinking each with its own sequence of development of sophistication, and its own sequence of developing warrants for truth, that in total spans the range of growth from the mathematics of new-born babies to the mathematics of research mathematicians. The title of this paper is a play on words, contrasting the act of ‘thinking through’ several existing theories of cognitive development, and ‘thinking through’ the newly formulated theory of three worlds to see how different individuals may develop substantially different paths on their own cognitive journey of personal mathematical growth. INTRODUCTIONThe International Group for the Psychology of Mathematics Education is a broad organisation with many ‘voices’ expressing a wide range of issues in mathematical teaching, learning and thinking. So broad are the views of its members that it moves over the years in ways that may not seem to present an overall universal picture. Yet there are themes that occur which focus on the psychology of cognitive growth of different individuals in mathematics education that begin to recur and link together to build a global framework. In this paper such themes are drawn out to formulate a long-term theory of cognitive development from conception to mature adult that encompasses a wide range of different paths taken by individuals, from discalculic children who make little progress, to research mathematicians who move forward the boundaries of the subject. THINKING THROUGH A RANGE OF THEORIES It is probably difficult for those of us looking at the huge range of current mathematics education research to imagine the state of the theory when the International Group for the Psychology of Mathematics Education was first conceived. Psychology was still in the grips of behaviorism, with the teaching of mathematics largely in the hands of mathematical practitioners and general educators, and just a few major theorists, such as Piaget (1965), Dienes (1960) and Bruner (1966), having something to say that had particular relevance in mathematics. At the time, Piagetian theories held sway, with an emphasis on successive stages of development and a particular focus on the transitions between stages. Underlying Piagetian theory was a tripartite theory of abstraction: empirical abstraction focusing on how the child constructs meaning for the properties of objects, pseudo-empirical abstraction, focusing on construction of meaning for the properties of actions on objects, and reflective abstraction focused on the idea of how ‘actions and operations become thematized objects of thought or assimilation’ (Piaget, 1985, p. 49). Meanwhile, in a somewhat different direction, Bruner focused on three distinct ways
Dexterity and two-point discrimination of the hand in school-aged children with dysgraphia

Background: Dysgraphia as a problem with handwriting, affects student’s performance in school activities and participation. The purpose of the study was to compare dexterity and two-point discrimination of the hand between learning disabled students with dysgraphia and healthy students. Methods: Forty-three students with developmental dysgraphia and 55 normal students in grade two to four from special and regular schools participated in this study. Hand dexterity and static/dynamic discriminative touch were assessed via Purdue Pegboard and Two-Point Discriminator respectively. Results: Significant differences were found in Purdue Pegboard scores between two groups except in doing the test with the left hand (p<0.05). Purdue Pegboard scores were significantly lower in left-handed children with dysgraphia compared to healthy children (p<0.05). There was no significant difference in dynamic two point discrimination between two groups of children (p>0.05). Static two-point discrimination of the thumb finger was significantly higher in children with dysgraphia (p<0.05). Conclusion: Hand dexterity affects handwriting performance in children with dysgraphia. There were no correlations between two-point discrimination and Purdue Pegboard scores of children with dysgraphia. Intervention should focus on other aspects of dexterity rather than sensory components. Hand dominancy also may be a factor influencing hand performance in dysgraphia.
Dynamic Alterations to α-Actinin Accompanying Sarcomere Disassembly and Reassembly during Cardiomyocyte Mitosis

Although mammals are thought to lose their capacity to regenerate heart muscle shortly after birth, embryonic and neonatal cardiomyocytes in mammals are hyperplastic. During proliferation these cells need to selectively disassemble their myofibrils for successful cytokinesis. The mechanism of sarcomere disassembly is, however, not understood. To study this, we performed a series of immunofluorescence studies of multiple sarcomeric proteins in proliferating neonatal rat ventricular myocytes and correlated these observations with biochemical changes at different cell cycle stages. During myocyte mitosis, α-actinin and titin were disassembled as early as prometaphase. α-actinin (representing the sarcomeric Z-disk) disassembly precedes that of titin (M-line), suggesting that titin disassembly occurs secondary to the collapse of the Z-disk. Sarcomere disassembly was concurrent with the dissolution of the nuclear envelope. Inhibitors of several intracellular proteases could not block the disassembly of α-actinin or titin. There was a dramatic increase in both cytosolic (soluble) and sarcomeric α-actinin during mitosis, and cytosolic α-actinin exhibited decreased phosphorylation compared to sarcomeric α-actinin. Inhibition of cyclin-dependent kinase 1 (CDK1) induced the quick reassembly of the sarcomere. Sarcomere dis- and re-assembly in cardiomyocyte mitosis is CDK1-dependent and features dynamic differential post-translational modifications of sarcomeric and cytosolic α-actinin.
A shift from traditional pedagogy in Nepali Rural Primary Schools ? Rural teachers’ capacity to reflect ICT policy in their practice

Policy by the government of Nepal emphasises the need to develop ICT competencies and suggests the use of ICT will transform traditional models of teaching to ones that are studentcentred. This article reports a study of primary teachers’ experiences of using digital technologies in rural primary schools in Nepal, and investigates their preceptions of how the availability and use of ICT in their schools has transformed traditional teaching models. It further examines the resources they can access and the training they received. Teachers’ accounts of their experiences indicated that the integration of available digital technologies in instructional activities changed their role in the classroom to some extent, created a learner-friendly learning environment and improved aspects of their teaching. The study also found that there was often insufficient access to ICT in and outside the school premises, and that pre-service teacher education, as well as government-provided in-service training, does not cover the use of ICT in instructional activities. Rather provision of infrastructures and training in the use of digital devices is carried out by non-governmental organisations (NGOs). The article argues that for policy to be realised in practice, more sustainable and comprehensive systems need to be developed to train teachers in ICT use and to provide them with necessary facilities.
Detection of Head-to-Tail DNA Sequences of Human Bocavirus in Clinical Samples

Parvoviruses are single stranded DNA viruses that replicate in a so called “rolling-hairpin” mechanism, a variant of the rolling circle replication known for bacteriophages like ϕX174. The replication intermediates of parvoviruses thus are concatemers of head-to-head or tail-to-tail structure. Surprisingly, in case of the novel human bocavirus, neither head-to-head nor tail-to-tail DNA sequences were detected in clinical isolates; in contrast head-to-tail DNA sequences were identified by PCR and sequencing. Thereby, the head-to-tail sequences were linked by a novel sequence of 54 bp of which 20 bp also occur as conserved structures of the palindromic ends of parvovirus MVC which in turn is a close relative to human bocavirus.
Clinical evaluation of QuantiFERON TB-2G test for immunocompromised patients

The usefulness of the tuberculin skin test (TST) and the QuantiFERON TB-2G (QFT-TB) test were compared in immunocompromised patients. The subjects consisted of 252 immunocompromised patients who were clinically suspected of tuberculosis (TB) infection between April 2005 and December 2006. Regarding the underlying diseases, 74 subjects had malignant diseases, 72 were undergoing immunosuppressive treatment, 52 had diabetes mellitus, 50 had chronic renal failure and four had HIV infection. While the positive rate of the QFT-TB test for the diagnosis of TB infection (TB disease or latent TB infection) was 78.1%, that of TST for TB infection was 50.0%. The QFT-TB test was significantly better than TST. However, 32 (13%) patients had an indeterminate QFT-TB result. Indeterminate findings were significantly more frequent in patients receiving immunosuppressive treatment (28%), especially with lymphocytopaenia in the peripheral blood, than in those who had other underlying diseases. While TST-positive and QFT-TB test-negative results were recognised in immunocompromised patients with bacille Calmette–Guérin vaccination or nontuberculous mycobacterial disease, TST-negative and QFT-TB test-positive results were recognised in immunocompromised patients with a past history of TB infection. It was concluded that the QuantiFERON TB-2G test is a more useful diagnostic method for tuberculosis infection than tuberculin skin test for immunocompromised patients suspected of tuberculosis disease. However, because the results of the QuantiFERON TB-2G test show an indeterminate response for patients receiving immunosuppressive treatment, especially for those with lymphocytopaenia due to severe underlying diseases, care must be taken in the interpretation of the QuantiFERON TB-2G test for these patients.
Classical to quantum transition of a driven nonlinear nanomechanical resonator

Much experimental effort is invested these days in fabricating nanoelectromechanical systems (NEMS) that are sufficiently small, cold and clean, so as to approach quantum mechanical behavior as their typical quantum energy scale becomes comparable with that of the ambient thermal energy kBT. Such systems will hopefully enable one to observe the quantum behavior of human-made objects, and test some of the basic principles of quantum mechanics. Here, we expand and elaborate on our recent suggestion (Katz et al 2007 Phys. Rev. Lett. 99 040404) to exploit the nonlinear nature of a nanoresonator in order to observe its transition into the quantum regime. We study this transition for an isolated resonator, as well as one that is coupled to a heat bath at either zero or finite temperature. We argue that by exploiting nonlinearities, quantum dynamics can be probed using technology that is almost within reach. Numerical solutions of the equations of motion display the first quantum corrections to classical dynamics that appear as the classical-to-quantum transition occurs. This provides practical signatures to look for in future experiments with NEMS resonators.
A Retransmission Cut-Off Random Access Protocol with Multi-packet Reception Capability for Wireless Networks

A retransmission cut-off algorithm for Slotted ALOHA random access protocol is studied in terms of the new packet generation rate, the number of retransmission trials and the Multi-packet Reception capacity. The retransmission cut-off is not needed for a stable operation of Slotted ALOHA if the new packet generation rate is below a critical limit. The values of these critical limits increase almost linearly with the increase of MPR capability. The throughput never reaches its maximum value if the new packet generation rate is less than the corresponding critical limits irrespective of the number of retransmission trials. The maximum throughput is attained by adjusting the number of retransmission trials, pertaining to the new packet generation rate exceeding the corresponding critical limits. A complete analysis for the new packet generation rate with the proper adjustment of the number of retransmission trials and the Multi-packet Reception capability that maximizes the channel throughput and stable operation is found. The stable and unstable operating regions in terms of the new packet generation rate, the number of retransmission trials and the Multi-packet Reception capability is devised. The throughput and packet rejection probability of retransmission cut-off Slotted ALOHA with Multi-packet Reception capability are also provided.
Estimated Value of Non-Price Vertical Coordination in the Fed Cattle Market

Subcontract entitled, "Estimating the Value of Vertical Coordination of Quantity in the Beef Industry," with Oklahoma State University. Economic gains appear to be possible for both cattle feeders and packers with improved coordination of the flow of cattle from feedlots to packing plants. From the packer's viewpoint, estimates made in this study indicate that a steady daily flow of cattle into their plant, a flow that is near their optimal processing capacity, will allow them to process cattle $2 to $5/head cheaper than is currently the norm for the industry. Estimates made indicate that packers could also save about $1/head if they could remove the fluctuations they experience in day-today slaughter rates. USDA data show that daily slaughter rates typically vary in beef processing plants by about 15 percent from day to day. In addition, it is estimated that packers can cut costs significantly by running within 5 percent of their optimal capacity rate. Five percent under-utilization of a plant costs the packer about $1/head. Ten percent under-utilization costs about $2.00/head and 15 percent under-utilization costs about $5.00/head (see Table 7). From the feedlot's perspective, being able to market cattle when they are ready has value. Growth/cost of gain simulators and serial slaughter data (which were used to determine how yield grades and quality grades change with slaughter weight and days on feed) indicate that the ability to sell cattle within one week of their optimal sales date can be worth $2 to $12/head. Estimates indicate that feedlots have about a two-week window to market cattle effectively. Within this window, profits do not change by more than about $1/head given a stable cash market. Avoiding the marketing of overweight cattle avoids heavy discounts for over-done cattle and the feed conversion inefficiency that is suffered when cattle are held too long. Typically, holding cattle about one week beyond the window reduces potential profit by about $2/head, and holding them two weeks beyond the window reduces the maximum potential profit by over $5/head. Selling cattle a week ahead of the window (i.e., " green ") typically results in about a $6/head loss. Selling them two weeks before the start of the window nets nearly a $12/head reduction in potential profit. It should be noted that these estimated costs of non-optimal slaughter dates depend partially upon the market-determined discounts for undesirable carcass characteristics. Therefore, they will vary somewhat over time. The magnitude of …
“A better person coming out than going in”: Community College Transfer Students and Constructivist Grounded Theory

ABSTRACT This study explored community college transfer student (CCTS) identity, development, and engagement at four-year institutions. The grounded theory approach was applied to develop CCTS-specific theories. Relational maps and interview questions were included in the research design to explore meaning making given the intersections of identity, development, and engagement. Findings revealed three interlocking concepts, the mechanisms that CCTSs use to cope unanticipated conflicts they experience upon transitioning to their four-year institutions, leading to the desire for self-improvement. Implications for policy, practice, and research in addition to the study’s limitations are also discussed.
The serotonin transporter linked polymorphic region and brain-derived neurotrophic factor valine to methionine at position 66 polymorphisms and maternal history of depression: Associations with cognitive vulnerability to depression in childhood

Abstract Preliminary work indicates that cognitive vulnerability to depression may be associated with variants of the serotonin transporter promoter polymorphism (5-HTTLPR) and the valine to methionine at position 66 (val66met) polymorphism of the brain-derived neurotrophic factor (BDNF) gene; however, existing reports come from small samples. The present study sought to replicate and extend this research in a sample of 375 community-dwelling children and their parents. Following a negative mood induction, children completed a self-referent encoding task tapping memory for positive and negative self-descriptive traits. Consistent with previous work, we found that children with at least one short variant of the 5-HTTLPR had enhanced memory for negative self-descriptive traits. The BDNF val66met polymorphism had no main effect but was moderated by maternal depression, such that children with a BDNF methionine allele had a heightened memory for negative self-descriptive traits when mothers had experienced depression during children's lifetimes; in contrast, children with a methionine allele had low recall of negative traits when mothers had no depression history. The findings provide further support for the notion that the 5-HTTLPR is associated with cognitive markers of depression vulnerability and that the BDNF methionine allele moderates children's sensitivity to contextual factors.
Adapting ranking SVM to document retrieval

The paper is concerned with applying learning to rank to document retrieval. Ranking SVM is a typical method of learning to rank. We point out that there are two factors one must consider when applying Ranking SVM, in general a "learning to rank" method, to document retrieval. First, correctly ranking documents on the top of the result list is crucial for an Information Retrieval system. One must conduct training in a way that such ranked results are accurate. Second, the number of relevant documents can vary from query to query. One must avoid training a model biased toward queries with a large number of relevant documents. Previously, when existing methods that include Ranking SVM were applied to document retrieval, none of the two factors was taken into consideration. We show it is possible to make modifications in conventional Ranking SVM, so it can be better used for document retrieval. Specifically, we modify the "Hinge Loss" function in Ranking SVM to deal with the problems described above. We employ two methods to conduct optimization on the loss function: gradient descent and quadratic programming. Experimental results show that our method, referred to as Ranking SVM for IR, can outperform the conventional Ranking SVM and other existing methods for document retrieval on two datasets.
The effect of PLLA/PVA nanofibrous scaffold on the chondrogenesis of human induced pluripotent stem cells

Abstract Human induced pluripotent stem cells (iPSCs) have been shown as an attractive source for cartilage repair and regenerative medicine. Chondrogenesis of iPSCs is important in cartilage tissue engineering. The objective of our study was enhanced chondrogenic differentiation of iPSCs by using Poly-L-lactic acid/polyvinyl alcohol (PLLA/PVA)-based scaffold and chondrogenic medium. PLLA scaffold was fabricated via electrospinning. The iPSC cells were cultured on the PLLA/PVA scaffold and scaffold-free method. Real-time PCR was performed to evaluate the cartilage-specific genes in the mRNA levels. Also, we have done immunocytochemistry and SEM imaging for confirming differentiation. Real-time PCR showed that significantly increased gene expression of collagen type II, collagen type X and aggrecan on the PLLA/PVA scaffold method when compared to the mRNA levels measured in the scaffold-free method. Down-regulation of Collagen I was observed in PLLA/PVA scaffold compared to scaffold-free. Also, both methods were shown a similar pattern of expression of SOX9. After 21 days, Immunocytochemistry and SEM imaging confirmed the differentiation of iPSC toward chondrocyte. Our results showed that PLLA/PVA scaffold maintain iPSC proliferation and differentiation, and can significantly enhance chondrogenic differentiation of iPSC. PLLA/PVA scaffold seeded iPSC showed the highest capacity for differentiation into chondrocyte-like cells. Graphical Abstract
Why Do People Act Like the Proverbial Ostrich? Investigating the Reasons That People Provide for Not Monitoring Their Goal Progress

Two studies examined peoples' reasons for not monitoring their progress toward their personal goals—a phenomenon that has been termed “the ostrich problem” (Webb et al., 2013). Study 1 used factor analysis to organize the reasons that people gave for not monitoring their goal progress, resulting in 10 factors. The most strongly endorsed reasons were: (a) that information on goal progress would demand a change in beliefs, or (b) undesired action; (c) that progress was poor, and (d) that thinking about and/or working on the goal was associated with negative emotions. Study 2 adopted a prospective design and investigated whether the reasons identified in Study 1 predicted: (a) the likelihood that participants would decline an opportunity to monitor their goal progress, and (b) the frequency with which participants monitored their goal progress. We found evidence that some of the most strongly endorsed reasons from Study 1 also predicted the avoidance of monitoring in Study 2; however, the belief that information about goal progress was likely to be inaccurate and not useful, and perceived control over goal attainment also reliably predicted the avoidance of monitoring in Study 2. Taken together, the findings explain why people do not monitor their goal progress and point to potential avenues for intervention.
Roles of interbasin frequency changes in the poleward shifts of the maximum intensity location of tropical cyclones

An observed poleward migration in the average latitude at which tropical cyclones (TCs) achieved their lifetime-maximum intensities (LMIs) was previously explained by changes in the mean meridional environments favorable to storm development linked to tropical expansion and anthropogenic warming. We show that the poleward migration is greatly influenced by basin-to-basin changes in TC frequency associated with multi-decadal variability, particularly for the Northern Hemisphere (NH). The contribution of the frequency changes to the poleward migration is comparable to that of the mean meridional environmental changes. A statistically significant global poleward trend can be identified simply from the frequency changes in each basin. An opposite trend exists in the frequency variations over the past 30 years between the North Atlantic and the eastern North Pacific where climatological mean latitudes of LMI are high (26.1°N) and low (16.5°N), respectively, which is the key factor in driving the frequency contribution. The strong roles of the interbasin frequency changes in the poleward migration also suggest that if the phase of multidecadal variability in the NH is reversed, as found in earlier TC records, the poleward trend could be changed to an opposite, equatorward, trend in the future.