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Reliable and Repeatable Characterication of Optical Streak Cameras
Optical streak cameras are used as primary diagnostics for a wide range of physics and laser experiments at facilities such as the National Ignition Facility (NIF). To meet the strict accuracy requirements needed for these experiments, the systematic nonlinearities of the streak cameras (attributed to nonlinearities in the optical and electrical components that make up the streak camera system) must be characterized. In some cases the characterization information is used as a guide to help determine how experiment data should be taken. In other cases, the characterization data are applied to the raw data images to correct for the nonlinearities. In order to characterize an optical streak camera, a specific set of data is collected, where the response to defined inputs are recorded. A set of analysis software routines has been developed to extract information such as spatial resolution, dynamic range, and temporal resolution from this data set. The routines are highly automated, requiring very little user input and thus provide very reliable and repeatable results that are not subject to interpretation. An emphasis on quality control has been placed on these routines due to the high importance of the camera characterization information
Global occurrence of Torque teno virus in water systems
Bacterial indicator organisms are used globally to assess the microbiological safety of waters. However, waterborne viral outbreaks have occurred in drinking water systems despite negative bacterial results. Using viral markers may therefore provide more accurate health risk assessment data. In this study, fecal, wastewater, stormwater, surface water (fresh and salt), groundwater, and drinking water samples were analyzed for the presence or concentration of traditional indicators, innovative indicators and viral markers. Samples were obtained in the United States, Italy, and Australia and results compared to those reported for studies conducted in Asia and South America as well. Indicators included total coliforms, Escherichia coli, enterococci, male-specific coliphages, somatic coliphages and microviradae. Viral markers included adenovirus, polyomavirus, and a potential new surrogate, Torque teno virus (TTV). TTV was more frequently found in wastewaters (38-100%) and waters influenced by waste discharges (25%) than in surface waters used as drinking water sources (5%). TTV was also specific to human rather than animal feces. While TTV numbers were strongly correlated to other viral markers in wastewaters, suggesting its utility as a fecal contamination marker, data limitations and TTV presence in treated drinking waters demonstrates that additional research is needed on this potential viral indicator
Survey of Tyrosine Kinase Signaling Reveals ROS Kinase Fusions in Human Cholangiocarcinoma
Cholangiocarcinoma, also known as bile duct cancer, is the second most common primary hepatic carcinoma with a median survival of less than 2 years. The molecular mechanisms underlying the development of this disease are not clear. To survey activated tyrosine kinases signaling in cholangiocarcinoma, we employed immunoaffinity profiling coupled to mass spectrometry and identified DDR1, EPHA2, EGFR, and ROS tyrosine kinases, along with over 1,000 tyrosine phosphorylation sites from about 750 different proteins in primary cholangiocarcinoma patients. Furthermore, we confirmed the presence of ROS kinase fusions in 8.7% (2 out of 23) of cholangiocarcinoma patients. Expression of the ROS fusions in 3T3 cells confers transforming ability both in vitro and in vivo, and is responsive to its kinase inhibitor. Our data demonstrate that ROS kinase is a promising candidate for a therapeutic target and for a diagnostic molecular marker in cholangiocarcinoma. The identification of ROS tyrosine kinase fusions in cholangiocarcinoma, along with the presence of other ROS kinase fusions in lung cancer and glioblastoma, suggests that a more broadly based screen for activated ROS kinase in cancer is warranted
How Sleep Affects Recovery and Performance in Basketball: A Systematic Review
Background: Sleep is considered an essential component related to physiological and psychological recovery in athletes and particularly in basketball, given the impact of condensed travel and game schedules on player health and performance. Objective: The aim of this systematic review is to examine studies published to date on sleep and basketball performance. Methodology: All scientific articles that reported a relationship between sleep and its possible impact on performance in basketball are included. The research processes followed the PRISMA criteria, and the relevant articles were extracted (PubMed, WOS, Scopus) as of December 31, 2021. Results: Twenty-eight articles were selected for inclusion and data extraction, with 27 demonstrating that sleep is a vital component in the recovery of basketball players and their corresponding on-court performance. Three central themes that we identified: (1) the quality and extension of sleep (the better quality and more extension of sleep, better performance and lower probability of injury); (2) influence of the players circadian rhythm (tTravel and game scheduling do not currently facilitate or take this into account); and (3) higher training loads and/or increased stress may jeopardize a subsequent good night's sleep, which should be taken into account when scheduling practices and workouts. Conclusion: The current systematic review regarding sleep and basketball performance and highlights that there is a strong relationship between both variables. Collectively, the evidence supports the critical influence of sleep on player recovery and basketball performance and risk for injury
A Genomic-Based Approach Combining In Vivo Selection in Mice to Identify a Novel Virulence Gene in Leishmania
Parasites of the genus Leishmania cause a variety of human diseases that range from destructive skin lesions caused by L. major to visceral infections of the liver and spleen caused by L. donovani that result in death. The Leishmania genes responsible for these different pathologies are not known. In the present study, we used a comparative genome-based approach to introduce and over-express L. donovani genes in L. major to determine whether this results in increased virulence of L. major in visceral organs of infected mice. Through this approach, a novel gene termed Li1040 was identified that is potentially involved in protein transport and was shown to increase pathogenesis in the visceral organs in mice. The Li1040 gene may therefore represent a Leishmania virulence gene that has the potential to regulate the pathology of infection in the mammalian host. These observations help to define how Leishmania causes fatal infections in humans and therefore provide a parasite-specific target for therapy
The hippocampus as the switchboard between perception and memory.
Adaptive memory recall requires a rapid and flexible switch
from external perceptual reminders to internal mnemonic representations.
However, owing to the limited temporal or spatial
resolution of brain imaging modalities used in isolation, the
hippocampal–cortical dynamics supporting this process remain
unknown. We thus employed an object-scene cued recall paradigm
across two studies, including intracranial electroencephalography
(iEEG) and high-density scalp EEG. First, a sustained increase in hippocampal
high gamma power (55 to 110 Hz) emerged 500 ms after
cue onset and distinguished successful vs. unsuccessful recall. This
increase in gamma power for successful recall was followed by a
decrease in hippocampal alpha power (8 to 12 Hz). Intriguingly,
the hippocampal gamma power increase marked the moment at
which extrahippocampal activation patterns shifted from perceptual
cue toward mnemonic target representations. In parallel,
source-localized EEG alpha power revealed that the recall signal
progresses from hippocampus to posterior parietal cortex and
then to medial prefrontal cortex. Together, these results identify
the hippocampus as the switchboard between perception and
memory and elucidate the ensuing hippocampal–cortical dynamics
supporting the recall process.post-print1844 K
Fabrication of cell container arrays with overlaid surface topographies
This paper presents cell culture substrates in the form of microcontainer arrays with overlaid surface topographies, and a technology for their fabrication. The new fabrication technology is based on microscale thermoforming of thin polymer films whose surfaces are topographically prepatterned on a micro- or nanoscale. For microthermoforming, we apply a new process on the basis of temporary back moulding of polymer films and use the novel concept of a perforated-sheet-like mould. Thermal micro- or nanoimprinting is applied for prepatterning. The novel cell container arrays are fabricated from polylactic acid (PLA) films. The thin-walled microcontainer structures have the shape of a spherical calotte merging into a hexagonal shape at their upper circumferential edges. In the arrays, the cell containers are arranged densely packed in honeycomb fashion. The inner surfaces of the highly curved container walls are provided with various topographical micro- and nanopatterns. For a first validation of the microcontainer arrays as in vitro cell culture substrates, C2C12 mouse premyoblasts are cultured in containers with microgrooved surfaces and shown to align along the grooves in the three-dimensional film substrates. In future stem-cell-biological and tissue engineering applications, microcontainers fabricated using the proposed technology may act as geometrically defined artificial microenvironments or niches
HIV-1 Genetic Diversity in Antenatal Cohort, Canada
Non-B HIV-1 was consistent with patients’ area of origin
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