Closing the Academic and Equity Gaps: How Achieving the Dream Redefined Assessment

This chapter will demonstrate how Achieving the Dream, a nonprofit leader of a national reform network of community colleges and open‐access universities, uses assessment to guide institutions toward a culture of evidence, equity and continuous improvement to improve student success.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/146378/1/ir20257_am.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/146378/2/ir20257.pd

Decoupling of a Neutron Interferometer from Temperature Gradients

Neutron interferometry enables precision measurements that are typically operated within elaborate, multi-layered facilities which provide substantial shielding from environmental noise. These facilities are necessary to maintain the coherence requirements in a perfect crystal neutron interferometer which is extremely sensitive to local environmental conditions such as temperature gradients across the interferometer, external vibrations, and acoustic waves. The ease of operation and breadth of applications of perfect crystal neutron interferometry would greatly benefit from a mode of operation which relaxes these stringent isolation requirements. Here, the INDEX Collaboration and National Institute of Standards and Technology demonstrates the functionality of a neutron interferometer in vacuum and characterize the use of a compact vacuum chamber enclosure as a means to isolate the interferometer from spatial temperature gradients and time-dependent temperature fluctuations. The vacuum chamber is found to have no depreciable effect on the performance of the interferometer (contrast) while improving system stability, thereby showing that it is feasible to replace large temperature isolation and control systems with a compact vacuum enclosure for perfect crystal neutron interferometry

A virulence activator of a surface attachment protein in Burkholderia pseudomallei acts as a global regulator of other membrane-associated virulence factors

Burkholderia pseudomallei (Bp), causing a highly fatal disease called melioidosis, is a facultative intracellular pathogen that attaches and invades a variety of cell types. We previously identified BP1026B_I0091 as a surface attachment protein (Sap1) and an essential virulence factor, contributing to Bp pathogenesis in vitro and in vivo. The expression of sap1 is regulated at different stages of Bp intracellular lifecycle by unidentified regulator(s). Here, we identified SapR (BP1026B_II1046) as a transcriptional regulator that activates sap1, using a high-throughput transposon mutagenesis screen in combination with Tn-Seq. Consistent with phenotypes of the Δsap1 mutant, the ΔsapR activator mutant exhibited a significant reduction in Bp attachment to the host cell, leading to subsequent decreased intracellular replication. RNA-Seq analysis further revealed that SapR regulates sap1. The regulation of sap1 by SapR was confirmed quantitatively by qRT-PCR, which also validated the RNA-Seq data. SapR globally regulates genes associated with the bacterial membrane in response to diverse environments, and some of the genes regulated by SapR are virulence factors that are required for Bp intracellular infection (e.g., type III and type VI secretion systems). This study has identified the complex SapR regulatory network and its importance as an activator of an essential Sap1 attachment factor

Measurement of Receptor-Activated Phosphoinositide Turnover in Rat Brain: Nonequivalence of Inositol Phosphate and CDP-Diacylglycerol Formation

Two methods for the measurement of receptor-activated phosphoinositide turnover were evaluated for their degree of correspondence in slices of rat brain; they involved the Li + -dependent accumulations of either [ 3 H]-inositol-labeled inositol phosphates or [ 3 H]cytidine-labeled CDP-diacylglycerol. In contrast to the expectation that the ratio of these two responses would remain approximately constant, varying degrees of correspondence were obtained. The two extremes are exemplified by carbachol, which elicited large increases in both inositol phosphate and CDP-diacylglycerol labeling, and endothelin, which gave a robust inositol phosphate response with little or no accumulation of 3 H-CDP-diacylglycerol. No instance of the presence of the latter response in the absence of 3 H-inositol phosphate accumulation was observed. Measurement of 3 H-CDP-diacylglycerol accumulation thus may add additional insight into the regulation of phosphoinositide turnover and the complex actions of Li + .Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/66135/1/j.1471-4159.1993.tb03258.x.pd

Possible origins of macroscopic left-right asymmetry in organisms

I consider the microscopic mechanisms by which a particular left-right (L/R) asymmetry is generated at the organism level from the microscopic handedness of cytoskeletal molecules. In light of a fundamental symmetry principle, the typical pattern-formation mechanisms of diffusion plus regulation cannot implement the "right-hand rule"; at the microscopic level, the cell's cytoskeleton of chiral filaments seems always to be involved, usually in collective states driven by polymerization forces or molecular motors. It seems particularly easy for handedness to emerge in a shear or rotation in the background of an effectively two-dimensional system, such as the cell membrane or a layer of cells, as this requires no pre-existing axis apart from the layer normal. I detail a scenario involving actin/myosin layers in snails and in C. elegans, and also one about the microtubule layer in plant cells. I also survey the other examples that I am aware of, such as the emergence of handedness such as the emergence of handedness in neurons, in eukaryote cell motility, and in non-flagellated bacteria.Comment: 42 pages, 6 figures, resubmitted to J. Stat. Phys. special issue. Major rewrite, rearranged sections/subsections, new Fig 3 + 6, new physics in Sec 2.4 and 3.4.1, added Sec 5 and subsections of Sec

Fusion of short telomeres in human cells is characterized by extensive deletion and microhomology, and can result in complex rearrangements

Telomere fusion is an important mutational event that has the potential to lead to large-scale genomic rearrangements of the types frequently observed in cancer. We have developed single-molecule approaches to detect, isolate and characterize the DNA sequence of telomere fusion events in human cells. Using these assays, we have detected complex fusion events that include fusion with interstitial loci adjacent to fragile sites, intra-molecular rearrangements, and fusion events involving the telomeres of both arms of the same chromosome consistent with ring chromosome formation. All fusion events were characterized by the deletion of at least one of the telomeres extending into the sub-telomeric DNA up to 5.6 kb; close to the limit of our assays. The deletion profile indicates that deletion may extend further into the chromosome. Short patches of DNA sequence homology with a G:C bias were observed at the fusion point in 60% of events. The distinct profile that accompanies telomere fusion may be a characteristic of the end-joining processes involved in the fusion event

Bad influence? – an investigation into the purported negative influence of foreign domestic helpers on children's second language English acquisition

This paper explores the purported negative influence of foreign domestic helpers (FDHs) on child second language acquisition (SLA) by studying Hong Kong Cantonese children's listening ability in second language (L2) English. 31 kindergarten third graders aged 4;6 to 6, and 29 first year secondary students aged 11-14 who have had a Filipino domestic helper at home took part in the study. In addition, 34 youngsters (20 in kindergarten, 14 in secondary) who did not have a Filipino helper participated as controls. Results from two listening tasks (picture choosing task, sound discrimination task) suggest that informants do not differ from the control in their abilities to listen to American-, British-, and Hong Kong English, and that they are better at listening to Filipino-accented English than the control. These findings cast doubts on the anecdotal belief of the harmful effect FDHs have on children's language acquisition including an L2. Moreover, the additional effect of being familiar with another variety of English is arguably a desirable outcome given that English is used as a lingua franca among non-native speakers on a daily basis in this highly globalised world

Pc1-Pc2 waves and energetic particle precipitation during and after magnetic storms: superposed epoch analysis and case studies

Magnetic pulsations in the Pc1-Pc2 frequency range (0.1-5 Hz) are often observed on the ground and in the Earth's magnetosphere during the aftermath of geomagnetic storms. Numerous studies have suggested that they may play a role in reducing the fluxes of energetic ions in the ring current; more recent studies suggest they may interact parasitically with radiation belt electrons as well. We report here on observations during 2005 from search coil magnetometers and riometers installed at three Antarctic stations, Halley (-61.84 degrees magnetic latitude, MLAT), South Pole (-74.18 degrees MLAT), and McMurdo (-79.96 degrees MLAT), and from energetic ion detectors on the NOAA Polar-orbiting Operational Environment Satellites (POES). A superposed epoch analysis based on 13 magnetic storms between April and September 2005 as well as case studies confirm several earlier studies that show that narrowband Pc1-Pc2 waves are rarely if ever observed on the ground during the main and early recovery phases of magnetic storms. However, intense broadband Pi1-Pi2 ULF noise, accompanied by strong riometer absorption signatures, does occur during these times. As storm recovery progresses, the occurrence of Pc1-Pc2 waves increases, at first in the daytime and especially afternoon sectors but at essentially all local times later in the recovery phase (typically by days 3 or 4). During the early storm recovery phase the propagation of Pc1-Pc2 waves through the ionospheric waveguide to higher latitudes was more severely attenuated. These observations are consistent with suggestions that Pc1-Pc2 waves occurring during the early recovery phase of magnetic storms are generated in association with plasmaspheric plumes in the noon-to-dusk sector, and these observations provide additional evidence that the propagation of waves to ground stations is inhibited during the early phases of such storms. Analysis of 30- to 250-keV proton data from four POES satellites during the 24-27 August and 18-19 July 2005 storm intervals showed that the location of the inner edge of the ring current matched well with the plasmapause model of O'Brien and Moldwin (2003). However, the POES data showed no evidence of the consequences of electromagnetic ion cyclotron waves (localized proton precipitation) during main and early recovery phase. During later stages of the recovery phase, when such precipitation was observed, it was coincident with intense wave events at Halley, and it occurred at L shells near or up to 1 RE outside the modeled plasmapause but well equatorward of the isotropy boundary

Uridine Metabolism in the Goldfish Retina During Optic Nerve Regeneration: Cell-Free Preparations

The activities of uridine kinase (EC 2.7.1.48), uridine monophosphate (UMP) kinase (EC 2.7.1.3.14), and uridine diphosphate (UDP) kinase (EC 2.7.4.6) were measured in retinal high-speed supernatant fractions following unilateral optic nerve crush in the goldfish. The enzyme activities followed a similar time course, with initial increases 2-3 days following nerve crush, peak activity at 4 days, and a gradual return to basal levels by day 21. The magnitude of the stimulation on day 4 was about 35% in each case. Activities of two enzymes of intermediary metabolism, pyruvate kinase (EC 2.7.1.40) and lactic dehydrogenase (EC 1.1.1.27), were not altered, indicating that the coordinate increases in nucleoside and nucleotide kinase activities were specific responses to the nerve injury. The increased labeling could not be explained by altered phosphohydrolytic activities. The nature of the enhancement was further studied in UDP kinase, the most active of the kinases examined. Neither low-molecular-weight components nor substrate availability could account for the observed increase in UDP kinase in the 4 day post-crush retinas. The K m , for UDP was unaltered, and a mixing experiment did not support the possibility that stimulatory or inhibitory factors played a role. The enhancement of UDP kinase activity was blocked by injection of actinomycin D following nerve crush. The results suggest that the observed increases in enzymes of uridine metabolism result from their increased formation following nerve crush.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/65504/1/j.1471-4159.1981.tb01714.x.pd