Naresuan University Journal
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Alienation in mathematics education: critique and development of neo-Vygotskian perspectives
No full textThis paper aims to critique and develop neo-Vygotskian work in mathematics education from (i) within the Vygotskian and activity theoretic tradition, and where necessary from (ii) a Bourdieusian perspective. First, I critique Roth and Radford’s (2011) version of Cultural-historical Activity Theory, suggesting that a classroom episode presented as developmental might be seen as a process of alienation. I trace this to the institutional structure of schooling, in which curriculum and pedagogy are alienated from the learner’s everyday sense. Next, I examine and critique the Vygotskian ‘Funds of Knowledge’ approach to critical mathematics education, which seeks to overcome alienation by subjecting the curriculum to the needs of the poor communities the school serves. Here, the critical point on alienation in the Vygotskian approach is better argued in Bourdieu’s perspective on educational institutions as reproductive of class domination. Finally, the paper discusses the extent to which these critiques pertain to Vygotskian activity theory in general or only to these versions in particular and draws implications for the development of a critical mathematics education perspective in a synthesis of perspectives from Vygotsky and Bourdieu
Synthetic enzyme-substrate tethering obviates the Tolloid-ECM interaction during Drosophila BMP gradient formation.
No full textMembers of the Tolloid family of metalloproteinases liberate BMPs from inhibitory complexes to regulate BMP gradient formation during embryonic dorsal-ventral axis patterning. Here, we determine mechanistically how Tolloid activity is regulated by its non-catalytic CUB domains in the Drosophila embryo. We show that Tolloid, via its N-terminal CUB domains, interacts with Collagen IV, which enhances Tolloid activity towards its substrate Sog, and facilitates Tsg-dependent stimulation of cleavage. In contrast, the two most C-terminal Tld CUB domains mediate Sog interaction to facilitate its processing as, based on our structural data, Tolloid curvature positions bound Sog in proximity to the protease domain. Having ascribed functions to the Tolloid non-catalytic domains, we recapitulate embryonic BMP gradient formation in their absence, by artificially tethering the Tld protease domain to Sog. Our studies highlight how the bipartite function of Tolloid CUB domains, in substrate and ECM interactions, fine-tune protease activity to a particular developmental context
The effects of esterification on the humidity-dependent glass transition of human hair
No full textHuman hair is a highly complex biomaterial. For the analysis of its mechanical and thermal properties it is, however, well described by a two-phase structure, which contains as morphological components the highly-ordered, crystalline intermediate filaments (IFs) and the less-ordered, amorphous matrix. A previous study has shown that wool compared to human hair exhibits for the whole range of water contents higher values for the glass transition temperature, Tg, as a property of the matrix. This is despite a higher content of hydrophobic, high glycine-tyrosine (HGT) proteins contained within the matrix of human hair. On this basis, the internal plasticization (IP) hypothesis was developed, stating that the composition of the matrix is the controlling factor of the glass transition and that, namely, the HGT-proteins may have a plasticization effect in the matrix. To further evaluate this hypothesis, esterifications of the hair proteins with various alcohols were carried out to introduce additional and variable hydrophobic sites into the fiber. The effects of these modifications on the humidity-dependent Tg of hair are analysed on the basis of the Fox-equation. It is shown that all esterifications lead to a systematic decrease of, the Tg-values in line with the IP-hypothesis
EPA guidance on the early detection of clinical high risk states of psychoses.
No full textThe aim of this guidance paper of the European Psychiatric Association is to provide evidence-based recommendations on the early detection of a clinical high risk (CHR) for psychosis in patients with mental problems. To this aim, we conducted a meta-analysis of studies reporting on conversion rates to psychosis in non-overlapping samples meeting any at least any one of the main CHR criteria: ultra-high risk (UHR) and/or basic symptoms criteria. Further, effects of potential moderators (different UHR criteria definitions, single UHR criteria and age) on conversion rates were examined. Conversion rates in the identified 42 samples with altogether more than 4000 CHR patients who had mainly been identified by UHR criteria and/or the basic symptom criterion 'cognitive disturbances' (COGDIS) showed considerable heterogeneity. While UHR criteria and COGDIS were related to similar conversion rates until 2-year follow-up, conversion rates of COGDIS were significantly higher thereafter. Differences in onset and frequency requirements of symptomatic UHR criteria or in their different consideration of functional decline, substance use and co-morbidity did not seem to impact on conversion rates. The 'genetic risk and functional decline' UHR criterion was rarely met and only showed an insignificant pooled sample effect. However, age significantly affected UHR conversion rates with lower rates in children and adolescents. Although more research into potential sources of heterogeneity in conversion rates is needed to facilitate improvement of CHR criteria, six evidence-based recommendations for an early detection of psychosis were developed as a basis for the EPA guidance on early intervention in CHR states
Lung-Function Trajectories Leading to Chronic Obstructive Pulmonary Disease.
No full textBACKGROUND: Chronic obstructive pulmonary disease (COPD) is thought to result from an accelerated decline in forced expiratory volume in 1 second (FEV1) over time. Yet it is possible that a normal decline in FEV1 could also lead to COPD in persons whose maximally attained FEV1 is less than population norms. METHODS: We stratified participants in three independent cohorts (the Framingham Offspring Cohort, the Copenhagen City Heart Study, and the Lovelace Smokers Cohort) according to lung function (FEV1 ≥80% o
Principles- versus Rules-Based Output Statistical Disclosure Control in Remote Access Environments
No full textSearch for metastable heavy charged particles with large ionisation energy loss in pp collisions at TeV using the ATLAS experiment
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A HPLC-SRM-MS based method for the detection and quantification of methotrexate in urine at doses used in clinical practice for patients with rheumatological disease: a potential measure of adherence.
No full textRheumatoid arthritis (RA) is a common autoimmune disease that causes significant disability and reduced life expectancy. The folate antagonist methotrexate (MTX) is first-line therapy for RA when used weekly at low doses (5-25 mg). However, the true rate of adherence to MTX is uncertain. This is in part due to the different methods of measurement of adherence employed with no biochemical test currently available to determine adherence to low dose MTX. Common methods of MTX measurement include immunoassays in patients with high dose therapy, but these assays cross-react with MTX metabolites and lack the sensitivity required to measure adherence to low dose MTX. HPLC-SRM-MS (selected reaction monitoring-mass spectrometry) has several theoretical advantages over immunoassays with improved specificity, minimal cross-reaction and higher sensitivity. The aim of this study was to develop an assay to measure MTX and its major metabolite 7-OH-MTX in urine as a tool to monitor adherence to low dose MTX in clinic. As a proof of concept, urine samples from 4 participants with RA were measured after directly observed therapy. The assay showed improved sensitivity compared to that reported by immunoassays, with low carryover and high within-run precision. In participant samples, MTX was measurable in the urine for up to 105 hours after administration and 7-OH-MTX was detectable up to 98 hours after administration, suggesting that this assay is suitable for the measurement of adherence to therapy. The assay requires minimal sample preparation and can be adopted by other laboratories with minimal study set up
การศึกษาปัจจัยในการกัดชิ้นงานด้วยเม็ดมีด APMT1604PDER-M2 ที่มีผลต่ออายุการใช้งานของคมตัดและความเรียบผิว
Get PDF การศึกษาครั้งนี้มีวัตถุประสงค์เพื่อศึกษาปัจจัยในการกัดชิ้นงานด้วยเม็ดมีด APMT1604 PDER-2M ที่มีผลต่ออายุการใช้งานของคมตัดและความเรียนผิว โดยทำการทดสอบการตัดเฉือนวัสดุเหล็กกล้าคาร์บอน(S45C) ปัจจัยที่มีผลต่ออายุการใช้งานของมีดกัดที่สำคัญคือความเร็วรอบ อัตราการป้อนและความลึกการป้อน นอกจากนี้ปัจจัยที่มีผลต่อคมตัดยังเกิดจากทิศทางการควบคุม ระยะในการป้อนตัดเฉือนงานด้านข้าง และการหล่อเย็น ดังนั้นงานวิจัยฉบับนี้จึงทำการทดลองโดยควบคุมความเร็วรอบ อัตราการป้อน ความลึกการป้อนและได้กำหนดปัจจัยในการศึกษาทดลองโดยกำหนดปัจจัย 3 ประเภทคือระยะการป้อน(Overlap) ทิศทางควบคุมการกัด (Cut Direction) และน้ำหล่อเย็น (Coolant) ตัวแปรคือความเรียบผิวของงาน ซึ่งอยู่ในขอบเขตที่กำหนดในมาตรฐานงานกัดความเรียบผิว (Ra) ≤ 1.6 ไมโครเมตร ใช้ความเร็วรอบคงที่ 960 รอบ/นาที โดยมีการกำหนดระดับปัจจัย 2 ระดับคือระยะการป้อน(Overlap) ที่ 2 มิลลิเมตรและ 4 มิลลิเมตร ทิศทางการเคลื่อนที่ตัดเฉือนแบบ(Climb Milling)และการเคลื่อนที่ตัดเฉือนแบบ(Conventional Milling) การปิดและเปิด น้ำหล่อเย็น จากการศึกษาพบว่าปัจจัยที่มีผลต่ออายุการใช้งานและความเรียบผิวงานคือระยะการป้อน(Overlap) ทิศทางควบคุมการกัด (Cut Direction) และการปิดเปิดน้ำหล่อเย็น มีผลต่ออายุการใช้งานของเม็ดมีดอย่างมีนัยสำคัญที่ระดับ 0.05 ระดับของปัจจัยที่เหมาะสมที่สุดคือทิศทางการเคลื่อนที่การตัดเฉือนควรใช้แบบ(Climb Milling) ควรปิดน้ำหล่อเย็นและระยะการป้อน(Overlap) ที่ 2 มิลลิเมตร ซึ่งทำให้อายุการใช้งานเม็ดมีดสามารถใช้งานได้อย่างเติมประสิทธิภาพมีคุณภาพความเรียบผิวงานที่ดีและมีอายุการใช้งานนานขึ้น
คำสำคัญ: ระยะการป้อน ทิศทางการควบคุมการกัด น้ำหล่อเย็น การกัดชิ้นงานด้วยเม็ดมีด ค่าความเรียบผิว อายุการใช้งานของคมตัด
This study aimed to identify factors in the milling inserts APMT1604 PDER-2M affecting to the utilization duration of cutting by considering the test machining carbon steel (S45C) Factors affecting the utilization duration of cutting are wind speed, feed rate and feed depth .In addition, factors that affect the cutting are also occurring from direction, overlap and coolant. Therefore, this research is conducted by controlled experiments the cutting speed, feed rate, feed depth and determining three factors include overlap, cut direction and coolant. The smooth surface variable could define the standard of milling surface roughness (Ra) ≤1.6 micrometers which uses constant speed at 960 r/min by setting 2 level include overlap at 2 mm. and 4 mm. Moreover, setting climb milling, conventional milling, and coolant by controlling as closed and reopened are important to the utilization duration. The study found that the significant of cut direction, Overlap, and coolant on life time of cutting edge is 0.05. The best outcome can be achieved by using two millimeters overlap, climb milling and closed coolant.
Keywords: Overlap, Cut direction, Coolant, Milling tool inserts, Surface roughness, Lifetime of the cutting edge