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Book Review: Topographies of Whiteness: Mapping Whiteness in Library and Information Science
Teacher Perspectives on Reading Instruction in the Primary Grades
Research shows that teachers have both a passion and desire to teach reading feel conflicted by their pedagogical education, the district in which they teach, and government policies. Research suggests political agendas drive reading programs, reading curriculum, and teacher evaluations. The objective of this qualitative action research paper is to gain insight into primary grade teachers\u27 perspectives on their reading instruction. The teacher participants in the study feel ready and eager to teach reading. However, they routinely feel they are not supported by their individual school district, including the state and local governments, to teach reading effectively. The data collected from this research reinforced prior research surrounding teacher education preparedness, teacher support and resources, which highlight the struggles of reading instructio
Single electron charging of impurity sites visualized by scanning gate experiments on a quantum point contact
A quantum point contact (QPC) patterned on a two-dimensional electron gas is
investigated with a scanning gate setup operated at a temperature of 300 mK.
The conductance of the point contact is recorded while the local potential is
modified by scanning the tip. Single electron charging of impurities induced by
the local potential is observed as a stepwise conductance change of the
constriction. By selectively changing the state of some of these impurities, it
is possible to observe changes in transmission resonances of the QPC. The
location of such impurities is determined, and their density is estimated to be
below 50 per \mu m^2, corresponding to less than 1 % of the doping
concentration
A Millikelvin Scanned Probe for Measurement of Nanostructures
We demonstrate a scanning force microscope, based upon a quartz tuning fork,
that operates below 100 mK and in magnetic fields up to 6 T. The microscope has
a conducting tip for electrical probing of nanostructures of interest, and it
incorporates a low noise cryogenic amplifier to measure both the vibrations of
the tuning fork and the electrical signals from the nanostructures. At
millikelvin temperatures the imaging resolution is below 1 um in a 22 um x 22
um range, and a coarse motion provides translations of a few mm. This scanned
probe is useful for high bandwidth measurement of many high impedance
nanostructures on a single sample. We show data locating an SET within an array
and measure its coulomb blockade with a sensitivity of 2.6 x 10^-5 e/Hz^1/2.Comment: 5 pages, 5 figures, submitted to RS
Popular Concepts of Justice and Hybrid Judicial Institutions in Ghana
The provision of effective, legitimate and accessible justice is one of the most fundamental public goods expected from a well?governed state. In this article, we compare the legitimacy of three state or state?supported Ghanaian dispute settlement institutions: the magistrate's courts, the Commission on Human Rights and Administrative Justice (CHRAJ) and the land dispute committees of the neo?traditional Customary Land Secretariats (CLSs). It was found that popular beliefs and expectations are predominantly focused on the notion that justice requires a âbalanced process for establishing the truthâ, and that the procedures, codes and remedies used by the magistrate's courts and the CHRAJ were more congruent with these beliefs than those of the CLSs. The findings challenge stereotypes of popular and traditional justice as being primarily about reconciliation or restoration of communal harmony, and suggest that state institutions should be supported in their current development of hybrid and informal kinds of dispute settlement
Spatial Current Patterns, Dephasing and Current Imaging in Graphene Nanoribbons
Using the non-equilibrium Keldysh Green's function formalism, we investigate
the local, non-equilibrium charge transport in graphene nanoribbons (GNRs). In
particular, we demonstrate that the spatial current patterns associated with
discrete transmission resonances sensitively depend on the GNRs' geometry,
size, and aspect ratio, the location and number of leads, and the presence of
dephasing. We identify a relation between the spatial form of the current
patterns, and the number of degenerate energy states participating in the
charge transport. Furthermore, we demonstrate a principle of superposition for
the conductance and spatial current patterns in multiple-lead configurations.
We demonstrate that scanning tunneling microscopy (STM) can be employed to
image spatial current paths in GNR with atomic resolution, providing important
insight into the form of local charge transport. Finally, we investigate the
effects of dephasing on the spatial current patterns, and show that with
decreasing dephasing time, the current patterns evolve smoothly from those of a
ballistic quantum network to those of classical resistor network.Comment: 25 pages, 12 figure
Optimizing DNA Extraction Methods for Nanopore Sequencing of Neisseria gonorrhoeae Directly from Urine Samples
Empirical gonorrhea treatment at initial diagnosis reduces onward transmission. However, increasing resistance to multiple antibiotics may necessitate waiting for culture-based diagnostics to select an effective treatment. There is a need for same-day culture-free diagnostics that identify infection and detect antimicrobial resistance. We investigated if Nanopore sequencing can detect sufficient Neisseria gonorrhoeae DNA to reconstruct whole genomes directly from urine samples. We used N. gonorrhoeae-spiked urine samples and samples from gonorrhea infections to determine optimal DNA extraction methods that maximize the amount of N. gonorrhoeae DNA sequenced while minimizing contaminating host DNA. In simulated infections, the Qiagen UCP pathogen mini kit provided the highest ratio of N. gonorrhoeae to human DNA and the most consistent results. Depletion of human DNA with saponin increased N. gonorrhoeae yields in simulated infections but decreased yields in clinical samples. In 10 urine samples from men with symptomatic urethral gonorrhea, â„92.8% coverage of an N. gonorrhoeae reference genome was achieved in all samples, with â„93.8% coverage breath at â„10-fold depth in 7 (70%) samples. In simulated infections, if â„104 CFU/ml of N. gonorrhoeae was present, sequencing of the large majority of the genome was frequently achieved. N. gonorrhoeae could also be detected from urine in cobas PCR medium tubes and from urethral swabs and in the presence of simulated Chlamydia coinfection. Using Nanopore sequencing of urine samples from men with urethral gonorrhea, sufficient data can be obtained to reconstruct whole genomes in the majority of samples without the need for culture
From multiple perspectives to shared understanding
The aim of this study was to explore how learners operating in a small group reach shared understanding as they work out joint research questions and build a theoretical framework and to identify the resources and tools they used in the process. The learnersâ own interpretations of their group activities and learning were also taken into account. The data, consisting of group discussions and the documents produced by the group, were subjected to a qualitative content analysis. The group members employed a variety of resources and tools to exchange their individual perspectives and achieve shared understanding. Summaries of relevant literature laid a foundation for the groupâs theoretical discussions. Reflective comparisons between their book knowledge and their personal experiences of online interaction and collaboration were frequent, suggesting that such juxtapositions may have enhanced their learning by intertwining the content to be mastered and the activities entailed by this particular content
Four-month moxifloxacin-based regimens for drug-sensitive tuberculosis
Supported by the Global Alliance for TB Drug Development with support from the Bill and Melinda Gates Foundation, the European and Developing Countries Clinical Trials Partnership, U.S. Agency for International Development, U.K. Department for International Development, Directorate General for International Cooperation of the Netherlands, Irish Aid, Australia Department of Foreign Affairs and Trade, and National Institutes of Health, AIDS Clinical Trials Group and by grants from the National Institute of Allergy and Infectious Diseases (NIAID) (UM1AI068634, UM1 AI068636, and UM1AI106701) and by NIAID grants to the University of KwaZulu Natal, South Africa, AIDS Clinical Trials Group (ACTG) site 31422 (1U01AI069469); to the Perinatal HIV Research Unit, Chris Hani Baragwanath Hospital, South Africa, ACTG site 12301 (1U01AI069453); and to the Durban International Clinical Trials Unit, South Africa, ACTG site 11201 (1U01AI069426); Bayer Healthcare for the donation of moxifloxacin; and Sanofi for the donation of rifampin.Background: Early-phase and preclinical studies suggest that moxifloxacin-containing regimens could allow for effective 4-month treatment of uncomplicated, smear-positive pulmonary tuberculosis. Methods: We conducted a randomized, double-blind, placebo-controlled, phase 3 trial to test the noninferiority of two moxifloxacin-containing regimens as compared with a control regimen. One group of patients received isoniazid, rifampin, pyrazinamide, and ethambutol for 8 weeks, followed by 18 weeks of isoniazid and rifampin (control group). In the second group, we replaced ethambutol with moxifloxacin for 17 weeks, followed by 9 weeks of placebo (isoniazid group), and in the third group, we replaced isoniazid with moxifloxacin for 17 weeks, followed by 9 weeks of placebo (ethambutol group). The primary end point was treatment failure or relapse within 18 months after randomization. Results: Of the 1931 patients who underwent randomization, in the per-protocol analysis, a favorable outcome was reported in fewer patients in the isoniazid group (85%) and the ethambutol group (80%) than in the control group (92%), for a difference favoring the control group of 6.1 percentage points (97.5% confidence interval [CI], 1.7 to 10.5) versus the isoniazid group and 11.4 percentage points (97.5% CI, 6.7 to 16.1) versus the ethambutol group. Results were consistent in the modified intention-to-treat analysis and all sensitivity analyses. The hazard ratios for the time to culture negativity in both solid and liquid mediums for the isoniazid and ethambutol groups, as compared with the control group, ranged from 1.17 to 1.25, indicating a shorter duration, with the lower bounds of the 95% confidence intervals exceeding 1.00 in all cases. There was no significant difference in the incidence of grade 3 or 4 adverse events, with events reported in 127 patients (19%) in the isoniazid group, 111 (17%) in the ethambutol group, and 123 (19%) in the control group. Conclusions: The two moxifloxacin-containing regimens produced a more rapid initial decline in bacterial load, as compared with the control group. However, noninferiority for these regimens was not shown, which indicates that shortening treatment to 4 months was not effective in this setting. (Funded by the Global Alliance for TB Drug Development and others; REMoxTB ClinicalTrials.gov number, NCT00864383.)Publisher PDFPeer reviewe
External and internal noise surveys of London primary schools
Internal and external noise surveys have been carried out around schools in London, UK, to provide information on typical levels and sources to which children are exposed while at school. Noise levels were measured outside 142 schools, in areas away from flightpaths into major airports. 86% of the schools surveyed were exposed to noise from road traffic, the average external noise level outside a school being 57 dB LAeq. Detailed internal noise surveys have been carried out in 140 classrooms in 16 schools, together with classroom observations. It was found that noise levels inside classrooms depend upon the activities in which the children are engaged, with a difference of 20 dB LAeq between the 'quietest' and 'noisiest' activities. The average background noise level in classrooms exceeds the level recommended in current standards. The number of children in the classroom was found to affect noise levels. External noise influenced internal noise levels only when children were engaged in the quietest classroom activities. The effects of the age of the school buildings and types of window upon internal noise were examined but results were inconclusive
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