The effect of workplace noise exposure on reaction time

This study examined the effect of listening fatigue on the reaction time of normal hearing listeners, who work in noisy places, at different signal to noise ratios (quiet, +5 and +10 dB). Reaction time was measured using a single task paradigm on twelve male listeners (ages 23-58 years) before and after an eight hour shift at a noisy power plant. The participants in the study also completed a subjective rating questionnaire at two intervals, before and after the fatigue-inducing condition. Results of the study indicated that the reaction time was significantly longer for the most difficult listening condition, indicating the possibility that measurement of the reaction time was confounded by the lack of audibility. A learning effect on this particular reaction time task was also found because the results indicated shorter reaction times in the second session. Participants also subjectively rated significantly higher levels of fatigue on the rating scale after they were exposed to the fatigue-inducing condition. Results from this study indicate that caution should be taken when interpreting reaction time data as a measure of listening fatigue or listening effort. In conjunction with previous studies by Hulvey (2015) and Athey (2016) it is the author’s belief that reaction time is affected by signal to noise ratio and not directly by listening fatigue

My Patient or Law Enforcement, Who Gets First Say?

Law enforcement is often left struggling with determining how to appropriately respond to nurses who refuse their request to collect a suspect’s blood when that patient is suspected of intoxicated driving and the officer has a valid search warrant. These scenarios trigger compliance issues including a patient’s right to privacy and consent, “particularly when a medical entity’s compliance with the Health Insurance Portability and Accountability Act of 1996 (“HIPAA”) provisions directly conflicts with law enforcement needs and goals.” Once a suspect becomes a patient, whose interest prevails? Is it healthcare providers’ interest in abiding by the rights, health, and safety of their patients, or is it the State of Arkansas’s interest in deterring intoxicated driving? This Comment serves as a call on the Arkansas State Legislature to address the rising tensions between the medical field and law enforcement field by eliminating the broad discretion granted to medical providers which unjustly blocks the goals of law enforcement and to provide guidance, protection, and confidence to nurses in understanding their roles and responsibilities when acting for the state

Traditional Liberal Arts Colleges\u27 Consideration and Adoption of Online Education: A Presidential Perspective

National research studies have indicated that students are enrolling in more online courses annually (Allen & Seaman, 2010, 2014, 2015); yet, not all higher education institutions are adopting online education. In order to understand more about adoption of online education in higher education and presidents’ perceptions of online education, this study investigated the adoption of online education by traditional liberal arts colleges(TLACs). These institutions and their presidents currently face numerous challenges and threats as TLACs try to remain relevant in the 21st century while maintaining their liberal arts mission. The importance of this study lies in the realization that many higher education institutions and leaders are making decisions about the adoption of online education while also examining if and how online education aligns with their existing environment, mission, culture, and curricula. Drawing upon the diffusion of innovations theory as the framework for informing data collection, this study employed a two-phase, sequential mixed method design. Two research questions guided this study: 1) To what extent has online education been adopted at TLACs?; and 2) How do presidents at TLACs think about the adoption of online higher education in general, within traditional liberal arts institutions, and within their institutions specifically? In order to determine the level of online instructional education activity at each TLAC, the first phase was exploratory. The research sample for phase one of the study consisted of 55 TLACs that solely provided undergraduate curriculum in the arts and sciences. Major findings from phase one of the study indicated that more than half of TLACs (61.82%) did not have online education and did not offer any online courses. The remaining TLACs adopted online education either as fully online (16.36%) or hybrid (21.82%) courses. In the second phase, qualitative interviews with 11 TLAC presidents out of a population of 55 potential participants (20%) were conducted to understand how these administrators feel and think about the adoption of online education. Analyses of the TLAC presidential interviews resulted in three emergent themes: Apprehensions Regarding Online Education, Perceived Inferiority of Online Education, and Potential Opportunities From Online Education

Control valve: Hot gas fast response

The design of a warm gas control valve is reviewed outlining the problems posed by the requirement for extremely fast response combined with a severe environment and a hot, dirty, and corrosive operating fluid

Laboratory and tentative interstellar detection of trans-methyl formate using the publicly available Green Bank Telescope PRIMOS survey

The rotational spectrum of the higher-energy trans conformational isomer of methyl formate has been assigned for the first time using several pulsed-jet Fourier transform microwave spectrometers in the 6-60 GHz frequency range. This species has also been sought toward the Sagittarius B2(N) molecular cloud using the publicly available PRIMOS survey from the Green Bank Telescope. We detect seven absorption features in the survey that coincide with laboratory transitions of trans-methyl formate, from which we derive a column density of 3.1 (+2.6, -1.2) \times 10^13 cm-2 and a rotational temperature of 7.6 \pm 1.5 K. This excitation temperature is significantly lower than that of the more stable cis conformer in the same source but is consistent with that of other complex molecular species recently detected in Sgr B2(N). The difference in the rotational temperatures of the two conformers suggests that they have different spatial distributions in this source. As the abundance of trans-methyl formate is far higher than would be expected if the cis and trans conformers are in thermodynamic equilibrium, processes that could preferentially form trans-methyl formate in this region are discussed. We also discuss measurements that could be performed to make this detection more certain. This manuscript demonstrates how publicly available broadband radio astronomical surveys of chemically rich molecular clouds can be used in conjunction with laboratory rotational spectroscopy to search for new molecules in the interstellar medium.Comment: 40 pages, 7 figures, 4 tables; accepted for publication in Ap

Insights into activity-dependent map formation from the retinotectal system: a middle-of-the-brain perspective

ABSTRACT: The development of orderly topographic maps in the central nervous system (CNS) results from a collaboration of chemoaffinity cues that establish the coarse organization of the projection and activity-dependent mechanisms that fine-tune the map. Using the retinotectal projection as a model system, we describe evidence that biochemical tags and patterned neural activity work in parallel to produce topographically ordered axonal projections. Finally, we review recent experiments in other CNS projections that support the proposition that cooperation between molecular guidance cues and activity-dependent processes constitutes a general paradigm for CNS map formation

Cloning and Phylogenetic Analysis of NMDA Receptor Subunits NR1, NR2A and NR2B in Xenopus laevis Tadpoles

N-methyl-d-aspartate receptors (NMDARs) play an important role in many aspects of nervous system function such as synaptic plasticity and neuronal development. NMDARs are heteromers consisting of an obligate NR1 and most commonly one or two kinds of NR2 subunits. While the receptors have been well characterized in some vertebrate and invertebrate systems, information about NMDARs in Xenopus laevis brain is incomplete. Here we provide biochemical evidence that the NR1, NR2A and NR2B subunits of NMDARs are expressed in the central nervous system of X. laevis tadpoles. The NR1-4a/b splice variants appear to be the predominant isoforms while the NR1-3a/b variants appear to be expressed at low levels. We cloned the X. laevis NR2A and NR2B subunits and provide a detailed annotation of their functional domains in comparison with NR2A and NR2B proteins from 10 and 13 other species, respectively. Both NR2A and NR2B proteins are remarkably well conserved between species, consistent with the importance of NMDARs in nervous system function

Insulin receptor signaling in the development of neuronal structure and function

Sensory experience plays a crucial role in regulating neuronal shape and in developing synaptic contacts during brain formation. These features are required for a neuron to receive, integrate, and transmit signals within the neuronal network so that animals can adapt to the constant changing environment. Insulin receptor signaling, which has been extensively studied in peripheral organ systems such as liver, muscle and adipocyte, has recently been shown to play important roles in the central nervous system. Here we review the current understanding of the underlying mechanisms that regulate structural and functional aspects of circuit development, particularly with respect to the role of insulin receptor signaling in synaptic function and the development of dendritic arbor morphology. The potential link between insulin receptor signaling malfunction and neurological disorders will also be discussed

Exosomes regulate neurogenesis and circuit assembly.

Exosomes are thought to be released by all cells in the body and to be involved in intercellular communication. We tested whether neural exosomes can regulate the development of neural circuits. We show that exosome treatment increases proliferation in developing neural cultures and in vivo in dentate gyrus of P4 mouse brain. We compared the protein cargo and signaling bioactivity of exosomes released by hiPSC-derived neural cultures lacking MECP2, a model of the neurodevelopmental disorder Rett syndrome, with exosomes released by isogenic rescue control neural cultures. Quantitative proteomic analysis indicates that control exosomes contain multiple functional signaling networks known to be important for neuronal circuit development. Treating MECP2-knockdown human primary neural cultures with control exosomes rescues deficits in neuronal proliferation, differentiation, synaptogenesis, and synchronized firing, whereas exosomes from MECP2-deficient hiPSC neural cultures lack this capability. These data indicate that exosomes carry signaling information required to regulate neural circuit development