The Validity And Reliability Of Value-Added And Target-Setting Procedures With Special Reference To Key Stage 3

The validity of value-added systems of measurement is crucially dependent upon there being a demonstrably unambiguous relationship between the so-called baseline, or intake measures, and any subsequent measure of performance at a later stage. The reliability of such procedures is dependent on the relationships between these two measures being relatively stable over time. A number of questions arise with regard to both the validity and reliability of value-added procedures at any level in education, but this appears to be particularly problematic at Key Stage 3. Target-setting procedures usually employ value-added data as the basis for predicting future performance, and the validity and reliability of target-setting procedures is therefore also problematic. In a five-year longitudinal case study of one secondary comprehensive school, the validity of both of these procedures was investigated using quantitative and qualitative methods. The validity and reliability of Key Stage 2 data, and data from the NFER Cognitive Abilities Test (CAT), as baseline data for value-added procedures, was investigated using regression analysis. Wider perceptions of value-added procedures were opened up using detailed interviews with a representative cross-section of teachers. Target-setting procedures were investigated by analysing numerical performance data in curriculum areas, by the use of questionnaires to students, staff and parents, and by detailed interviews with a representative sample of students. The results of the investigation suggest that whilst value-added procedures have a high level of validity and reliability for Mathematics at Key Stage 3, this is less true for English and Science. For non-core subjects there appears to be no rational basis upon which value-added procedures can be used. Staff attitudes towards both value-added and target-setting were often quite ambivalent; those of students and parents were generally much more positive. A number of concerns emerged with regard to the ways in which such procedures appear to be distorting teaching and learning, producing a culture of performativity where learning is increasingly seen as a means to an end, rather than a worthwhile end in itself. These findings raise some fundamental questions about our philosophy of education, about accountability, and about the knowledge claims which are made as a result of such procedures

CCD QE in the Soft X-ray Range

e2v has previously provided back-illuminated CCDs for several solar observation projects, resulting in a number of key articles on CCD QE in the soft X-ray region. To update these, e2v has arranged for tests on X-ray optimised EMCCDs at a synchrotron. These have shown QE of at least 45% from 40 eV to 2000 eV, with Enhanced process devices having significantly higher QE than Basic process. The measured values were similar to data published from the SDO SXI mission, showing that the e2v process has been stable over many years. The soft X-ray QE measurements show a reasonable fit to the simple layer model for energies > 600 eV. For energies < 100 eV, measurements show slightly lower QE than the model prediction for both Basic and Enhanced processes. For energies 100 eV to 600 eV, measurements show a reasonable fit to the model for the Basic process, but less improvement from the Enhanced process than the model predicts. Comparing the ~80% typical QE for UV-optimised CCDs at 385 nm with the 45% QE measured at 120 eV in this study, there is a discrepancy in QE for two photon energies with the same absorption length measured on CCDs from the same back-thinning process (one type with AR coating, one type without)

Monitoring Training Load Using the Acute: Chronic Workload Ratio in Non-Elite Intercollegiate Female Athletes

Monitoring training load and its progression in athletes is important to optimise adaptations to training while simultaneously preventing injury. A recent development in this field is the acute: chronic workload ratio (ACWR), which track s average acute training load against average chronic training load to describe training load progression. Furthermore, a new method of calculating the ACWR has been developed using exponentially weighted moving averages (EWMA) which accounts for the decay of fitness and fatigue. This study sought to investigate the relationship between the EWMA and ACWR (based upon session rating of perceived exertion (sRPE)), and injury risk in intercollegiate female athletes (N=4). Participants performed adductor squeeze tests (ASTs) once a week for 8 week s, while their training and wel lness were monitored with sRPE and a daily questionnaire respectively. A hierarchical regression demonstrated that monitoring of average sleep length, average stress, sRPE work loads and an EWMA provided the best model for predicting injury risk in athletes (R2 = 0.47). The findings indicate that the EWMA may be a effective training load monitoring tool than the ACWR model

Constraining the Carbon Budget of Peat Ecosystems: Application of Stoichiometry and Enthalpy Balances

We consider how the stoichiometry and energy content of organic matter reservoirs and fluxes through and from a peatland enable the fluxes and storage of carbon within a peatland to be constrained. We include the elemental composition of the above- and below-ground biomass, litter, the peat profile, and the dissolved and particulate organic matter within a blanket bog in northern England for which the C budget has previously been measured. The study shows, based only on the elemental composition, and calculation of oxidation and energy contents, that: (a) Dissolved organic carbon (DOC) in first-order streams is significantly more oxidized than in peat pore water but that there was no significant difference in organic carbon oxidation state down the peat profile; (b) The occurrence and speciation of N uptake and release in the peatland with N used and recycled can be predicted; (c) The relatively high oxidation state of DOC in stream water acts as an endpoint for peat-forming reactions; (d) Methanogenesis does not result in deep peat formation as its requirement for energy consumes too much organic matter to form residual peat at depth; (e) Sulfate reduction does occur during the formation of deep peat; (f) Organic matter elemental composition could be constrained to within three bounding equations though the proportions of carbon species could not be specified. (g) The formation of deep peat in this catchment could only be achieved if the dissolved organic matter (DOM) in the peat pore water is the dominant electron acceptor and energy source in the production of residual organic matter; however, it is unclear as to the flux of DOM up or down the peat profile

Comparison of Back-Thinned Detector Ultraviolet Quantum Efficiency for Two Commercially Available Passivation Treatments

Back-thinned silicon detectors offer a high response over a very broad spectrum for direct detection by providing an efficient optical path into the sensing silicon avoiding front face structures manufactured from metal, polysilicon, nitrides, and oxides that may absorb the incident light before reaching the sensing silicon. We have tested two CCDs with different back-surface shallow p+ implant thicknesses (basic and enhanced) at the M4 line (wavelength between 40 and 400 nm) at Physikalisch-Technische Bundesanstalt (PTB)’s Metrology Light Source in Berlin. This characterization in the ultraviolet spectral range extends the soft X-ray quantum efficiency (QE) data set previously acquired with the exact same devices. Due to the short absorption depth and the scope for many types of interactions of the device materials with ultraviolet photons, QE measurement and stability of the device against extended exposure in the UV are of ongoing interest. Therefore, QE measurements have been carried out before and after exposures to quantify any change in behavior. To allow characterization of the passivation processes only, the devices have no antireflection coating. The measured QE of the standard back-thinned CCD is below 10% between 70 and 370 nm. An average additional 5% efficiency is achieved in the enhanced device within the same range. At the limits of the measured spectrum, toward soft X-rays or toward the visible range, the QE increases and the difference between the standard and the enhanced process is reduced as the photon absorption length increases beyond the immediate back-surface. The measured QE after long high-flux exposures at 200 nm shows remarkable improvement

Effect of a reduction in glomerular filtration rate after nephrectomy on arterial stiffness and central hemodynamics: rationale and design of the EARNEST study

Background: There is strong evidence of an association between chronic kidney disease (CKD) and cardiovascular disease. To date, however, proof that a reduction in glomerular filtration rate (GFR) is a causative factor in cardiovascular disease is lacking. Kidney donors comprise a highly screened population without risk factors such as diabetes and inflammation, which invariably confound the association between CKD and cardiovascular disease. There is strong evidence that increased arterial stiffness and left ventricular hypertrophy and fibrosis, rather than atherosclerotic disease, mediate the adverse cardiovascular effects of CKD. The expanding practice of live kidney donation provides a unique opportunity to study the cardiovascular effects of an isolated reduction in GFR in a prospective fashion. At the same time, the proposed study will address ongoing safety concerns that persist because most longitudinal outcome studies have been undertaken at single centers and compared donor cohorts with an inappropriately selected control group.&lt;p&gt;&lt;/p&gt; Hypotheses: The reduction in GFR accompanying uninephrectomy causes (1) a pressure-independent increase in aortic stiffness (aortic pulse wave velocity) and (2) an increase in peripheral and central blood pressure.&lt;p&gt;&lt;/p&gt; Methods: This is a prospective, multicenter, longitudinal, parallel group study of 440 living kidney donors and 440 healthy controls. All controls will be eligible for living kidney donation using current UK transplant criteria. Investigations will be performed at baseline and repeated at 12 months in the first instance. These include measurement of arterial stiffness using applanation tonometry to determine pulse wave velocity and pulse wave analysis, office blood pressure, 24-hour ambulatory blood pressure monitoring, and a series of biomarkers for cardiovascular and bone mineral disease.&lt;p&gt;&lt;/p&gt; Conclusions: These data will prove valuable by characterizing the direction of causality between cardiovascular and renal disease. This should help inform whether targeting reduced GFR alongside more traditional cardiovascular risk factors is warranted. In addition, this study will contribute important safety data on living kidney donors by providing a longitudinal assessment of well-validated surrogate markers of cardiovascular disease, namely, blood pressure and arterial stiffness. If any adverse effects are detected, these may be potentially reversed with the early introduction of targeted therapy. This should ensure that kidney donors do not come to long-term harm and thereby preserve the ongoing expansion of the living donor transplant program.&lt;p&gt;&lt;/p&gt

The Neutral Gas Dynamics of the Nearby Magellanic Irregular Galaxy UGCA 105

We present new low-resolution HI spectral line imaging, obtained with the Karl G. Jansky Very Large Array (JVLA), of the star-forming Magellanic irregular galaxy UGCA 105. This nearby (D = 3.39+/-0.25 Mpc), low mass [M_HI=(4.3+/-0.5)x10^8 Solar masses] system harbors a large neutral gas disk (HI radius ~7.2 kpc at the N_HI=10^20 cm^-2 level) that is roughly twice as large as the stellar disk at the B-band R_25 isophote. We explore the neutral gas dynamics of this system, fitting tilted ring models in order to extract a well-sampled rotation curve. The rotation velocity rises in the inner disk, flattens at 72+/-3 km/s, and remains flat to the last measured point of the disk (~7.5 kpc). The dynamical mass of UGCA 105 at this outermost point, (9+/-2)x10^9 Solar masses, is ~10 times as large as the luminous baryonic components (neutral atomic gas and stars). The proximity and favorable inclination (55 degrees) of UGCA 105 make it a promising target for high-resolution studies of both star formation and rotational dynamics in a nearby low-mass galaxy.Comment: The Astronomical Journal, in pres