84 research outputs found
Promising Practices and Unfinished Business: Fostering Equity and Excellence for Black and Latino Males
Boston Public Schools (BPS) commissioned companion studies as part of its efforts to address achievement gaps for Black and Latino males. The first study revealed the increasing diversity of Black and Latino males and stark opportunity gaps throughout the system that contribute in large part to wide attainment gaps for these students. We hypothesized that in schools doing comparatively better with Black or Latino males than their counterparts, educators would be strategically and comprehensively implementing evidence-based cultural, structural, and instructional practices tailored to meet their the needs and aspirations of these students. Through qualitative case studies of four schools, we identified several cross-cutting themes that provide the district and school leaders with some positive news about effective practices found in all good schools: strong school cultures, professional collaboration, differentiated instruction, and, in the elementary schools, family engagement. While we observed pockets of best practices specific to Black and Latino male education, we also brought to light unfinished business, in that none of the four case study schools had an intentional and comprehensive schoolwide approach to educating Black and Latino males. This lack of intentionality resulted in a paucity of evidence that the school administration and faculty as a whole: (a) know and value students' cultural and linguistic backgrounds; (b) adopt explicit and responsive approaches to race and gender; and (c) develop and implement a comprehensive approach to culturally responsive curriculum and instruction. We posit that lack of knowledge, intentionality, and coherence impedes further progress in educating Black and Latino males, and has implications for educators in schools, for staff members in community partner organizations, and for family members of BPS students
Tree-based Unidirectional Neural Networks for Low-Power Computer Vision
This article describes the novel Tree-based Unidirectional Neural Network (TRUNK) architecture. This architecture improves computer vision efficiency by using a hierarchy of multiple shallow Convolutional Neural Networks (CNNs), instead of a single very deep CNN. We demonstrate this architecture’s versatility in performing different computer vision tasks efficiently on embedded devices. Across various computer vision tasks, the TRUNK architecture consumes 65% less energy and requires 50% less memory than representative low-power CNN architectures, e.g., MobileNet v2, when deployed on the NVIDIA Jetson Nano
Dynamic Mode Switching and Loosely Coupled Conformational Events Observed in Single Ribosomes
Evaluation of an Inexpensive Growth Medium for Direct Detection of Escherichia coli in Temperate and Sub-Tropical Waters
The cost and complexity of traditional methods for the detection of faecal indicator bacteria,
including E. coli, hinder widespread monitoring of drinking water quality, especially in lowincome
countries and outside controlled laboratory settings. In these settings the problem is
exacerbated by the lack of inexpensive media for the detection of E. coli in drinking water.
We developed a new low-cost growth medium, aquatest (AT), and validated its use for the
direct detection of E. coli in temperate and sub-tropical drinking waters using IDEXX QuantiTray1.
AT was compared with IDEXX Colilert-181 and either EC-MUG or MLSB for detecting
low levels of E. coli from water samples from temperate (n = 140; Bristol, UK) and subtropical
regions (n = 50, Pretoria/Tshwane, South Africa). Confirmatory testing (n = 418 and
588, respectively) and the comparison of quantitative results were used to assess performance.
Sensitivity of AT was higher than Colilert-181 for water samples in the UK [98.0%
vs. 86.9%; p<0.0001] and South Africa [99.5% vs. 93.2%; p = 0.0030]. There was no significant
difference in specificity, which was high for both media (>95% in both settings). Quantitative
results were comparable and within expected limits. AT is reliable and accurate for
the detection of E. coli in temperate and subtropical drinking water. The composition of the
new medium is reported herein and can be used freely
Magnetoelastic Coupling Through The Antiferromagnet-To-Ferromagnet Transition Of Quasi-Two-Dimensional [Cu(Hf2)(Pyz)(2)]Bf4 Using Infrared Spectroscopy
We investigated magnetoelastic coupling through the field-driven transition to the fully polarized magnetic state in quasi-two-dimensional [Cu(HF2)(pyz)(2)]BF4 by magnetoinfrared spectroscopy. This transition modifies out-of-plane ring distortion and bending vibrational modes of the pyrazine ligand. The extent of these distortions increases with the field, systematically tracking the low-temperature magnetization. These distortions weaken the antiferromagnetic spin exchange, a finding that provides important insight into magnetic transitions in other copper halides
Electron-Phonon And Magnetoelastic Interactions In Ferromagnetic Co[N(Cn)(2)](2)
We combined Raman and infrared vibrational spectroscopies with complementary lattice dynamics calculations and magnetization measurements to reveal the dynamic aspects of charge-lattice-spin coupling in Co[N(CN)(2)](2). Our work uncovers electron-phonon coupling as a magnetic field-driven avoided crossing of the low-lying Co2+ electronic excitation with two ligand phonons and a magnetoelastic effect that signals a flexible local CoN6 environment. Their simultaneous presence indicates the ease with which energy is transferred over multiple length and time scales in this system
Quantum Critical Transition Amplifies Magnetoelastic Coupling In Mn[N(Cn)(2)](2)
We report the discovery of a magnetic quantum critical transition in Mn[N(CN)(2)](2) that drives the system from a canted antiferromagnetic state to the fully polarized state with amplified magnetoelastic coupling as an intrinsic part of the process. The local lattice distortions, revealed through systematic phonon frequency shifts, suggest a combined MnN6 octahedra distortion + counterrotation mechanism that reduces antiferromagnetic interactions and acts to accommodate the field-induced state. These findings deepen our understanding of magnetoelastic coupling near a magnetic quantum critical point and away from the static limit
A Summary Catalogue of Microbial Drinking Water Tests for Low and Medium Resource Settings
Microbial drinking-water quality testing plays an essential role in measures to protect public health. However, such testing remains a significant challenge where resources are limited. With a wide variety of tests available, researchers and practitioners have expressed difficulties in selecting the most appropriate test(s) for a particular budget, application and setting. To assist the selection process we identified the characteristics associated with low and medium resource settings and we specified the basic information that is needed for different forms of water quality monitoring. We then searched for available faecal indicator bacteria tests and collated this information. In total 44 tests have been identified, 18 of which yield a presence/absence result and 26 of which provide enumeration of bacterial concentration. The suitability of each test is assessed for use in the three settings. The cost per test was found to vary from 5.00 for a presence/absence test and from 7.50 for a quantitative format, though it is likely to be only a small component of the overall costs of testing. This article presents the first comprehensive catalogue of the characteristics of available and emerging low-cost tests for faecal indicator bacteria. It will be of value to organizations responsible for monitoring national water quality, water service providers, researchers and policy makers in selecting water quality tests appropriate for a given setting and application
Evaluation of an Inexpensive Growth Medium for Direct Detection of Escherichia coli in Temperate and Sub-Tropical Waters
The cost and complexity of traditional methods for the detection of faecal indicator bacteria, including E. coli, hinder widespread monitoring of drinking water quality, especially in low-income countries and outside controlled laboratory settings. In these settings the problem is exacerbated by the lack of inexpensive media for the detection of E. coli in drinking water. We developed a new low-cost growth medium, aquatest (AT), and validated its use for the direct detection of E. coli in temperate and sub-tropical drinking waters using IDEXX Quanti-Tray®. AT was compared with IDEXX Colilert-18® and either EC-MUG or MLSB for detecting low levels of E. coli from water samples from temperate (n = 140; Bristol, UK) and subtropical regions (n = 50, Pretoria/Tshwane, South Africa). Confirmatory testing (n = 418 and 588, respectively) and the comparison of quantitative results were used to assess performance. Sensitivity of AT was higher than Colilert-18® for water samples in the UK [98.0% vs. 86.9%; p95% in both settings). Quantitative results were comparable and within expected limits. AT is reliable and accurate for the detection of E. coli in temperate and subtropical drinking water. The composition of the new medium is reported herein and can be used freely
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