154 research outputs found

    Gene Positioning in Chemosensitive and Chemoresistant Ovarian Cancer Cell Lines

    Get PDF
    Ovarian cancer is aggressive, silent (hidden for the majority of its development) and often resistant to cisplatin chemotherapy. Often, each cancer type has unique aneuploidy and gene repositioning, but patterns prevail; therefore, the focus of this study is to find the differences in patterns between sensitive and resistant ovarian cancer cells. If cells are resistant to cisplatin chemotherapy, then they will have specific gene repositioning and an increase in ploidy. Fluorescent In Situ Hybridization (FISH) will be utilized to track repositioning and count ploidy on three different ovarian cell lines, two sensitive to cisplatin and one resistant. Twenty-two different commercially manufactured fluorescent probes will attach to corresponding genes in the DNA of the ovarian cell in pairs. Microscopes and software with the help of the probes allow visualization of the desired genes in vitro. Ovarian cancer took 14,000 lives last year while the surviving 8,000 had a 75% reoccurrence rate which is often accompanied by chemotherapy resistance. Patterns within individual cancers exist and have been used for diagnosis and better understanding of the most effective chemotherapy in other cancers. Ovarian cancer is often undiagnosed until it has progressed to an advanced stage. When ovarian cancer reaches an advanced stage, 70-80% become resistant to platinum-based chemotherapy, like cisplatin. Using FISH to understand if gene repositioning or cell ploidy enables a cell to become resistant will make future diagnoses more efficient. If doctors can determine that the cancer will be resistant to cisplatin chemotherapy based on the gene count or position, then the patient can be redirected to other medication, saving time and increasing chances of survival. Ovarian cancer is commonly treated with cisplatin chemotherapy and as ovarian cancer is typically caught very late in the progression, any time saved is important

    Spatiotemporal variability in the O-18-salinity relationship of seawater across the tropical Pacific Ocean

    Full text link
    The relationship between salinity and the stable oxygen isotope ratio of seawater (δ18Osw) is of utmost importance to the quantitative reconstruction of past changes in salinity from δ18O values of marine carbonates. This relationship is often considered to be uniform across water masses, but the constancy of the δ18Osw-salinity relationship across space and time remains uncertain, as δ18Osw responds to varying atmospheric vapor sources and pathways, while salinity does not. Here we present new δ18Osw-salinity data from sites spanning the tropical Pacific Ocean. New data from Palau, Papua New Guinea, Kiritimati, and Galápagos show slopes ranging from 0.09 ‰/psu in the Galápagos to 0.32‰/psu in Palau. The slope of the δ18Osw-salinity relationship is higher in the western tropical Pacific versus the eastern tropical Pacific in observations and in two isotope-enabled climate model simulations. A comparison of δ18Osw-salinity relationships derived from short-term spatial surveys and multiyear time series at Papua New Guinea and Galápagos suggests spatial relationships can be substituted for temporal relationships at these sites, at least within the time period of the investigation. However, the δ18Osw-salinity relationship varied temporally at Palau, likely in response to water mass changes associated with interannual El Niño–Southern Oscillation (ENSO) variability, suggesting nonstationarity in this local δ18Osw-salinity relationship. Applying local δ18Osw-salinity relationships in a coral δ18O forward model shows that using a constant, basinwide δ18Osw-salinity slope can both overestimate and underestimate the contribution of δ18Osw to carbonate δ18O variance at individual sites in the western tropical Pacific.We are grateful for the dedicated water samplers who enabled this research: Lori J. Bell and Gerda Ucharm of the Coral Reef Research Foundation, Palau; Rosa Maritza Motoche Gonzalez and the Fuerza Aerea Ecuatoriana, Santa Cruz, Galapagos, Ecuador; Taonateiti Kabiri and the students of Tennessee Primary School, London, Kiritimati; and the Manus Weather Observers, U.S. Department of Energy ARM Climate Research Facility, Manus, Papua New Guinea. We would like to thank the Galapagos National Park, the Kiritimati Ministry of Environment Lands and Agricultural Development for sample permits, and the Charles Darwin Research Station for logistical support. Funding sources for this work includes NSF-AGS-PF 1049664 to J.L.C., NSF P2C2-1203785 to K.M.C., J.L.C., and D.N. This research was also supported by the Office of Biological and Environment Research of the U.S. Department of Energy as part of the Atmospheric Radiation Measurement Climate Research Facility. Isotope data are available as supporting information associated with the manuscript. (1049664 - NSF-AGS-PF; P2C2-1203785 - NSF; Office of Biological and Environment Research of the U.S. Department of Energy as part of the Atmospheric Radiation Measurement Climate Research Facility

    No Police in Schools: A Vision for Safe and Supportive Schools in CA

    Get PDF
    "No Police in Schools: A Vision for Safe and Supportive Schools in CA" analyzes data from the U.S. Department of Education's 2017-18 Civil Rights Data Collection (CRDC), the 2019 California Racial and Identity Profiling Act (RIPA) Stops dataset, and data from Stockton Unified School District on police in schools. The data conclusively show harmful and discriminatory policing patterns in schools. School police contribute to the criminalization of tens of thousands of California students, resulting in them being pushed out of school and into the school-to-prison pipeline. Critically, the data suggest that schools underreport the number of assigned law enforcement officers, so these problems are likely even more severe

    Varied Response of Western Pacific Hydrology to Climate Forcings over the Last Glacial Period

    Get PDF
    Atmospheric deep convection in the west Pacific plays a key role in the global heat and moisture budgets, yet its response to orbital and abrupt climate change events is poorly resolved. Here, we present four absolutely dated, overlapping stalagmite oxygen isotopic records from northern Borneo that span most of the last glacial cycle. The records suggest that northern Borneo’s hydroclimate shifted in phase with precessional forcing but was only weakly affected by glacial-interglacial changes in global climate boundary conditions. Regional convection likely decreased during Heinrich events, but other Northern Hemisphere abrupt climate change events are notably absent. The new records suggest that the deep tropical Pacific hydroclimate variability may have played an important role in shaping the global response to the largest abrupt climate change events

    Extended Cave Drip Water Time Series Captures the 2015–2016 El Niño in Northern Borneo

    Get PDF
    Time series of cave drip water oxygen isotopes (δ18O) provide site‐specific assessments of the contributions of climate and karst processes to stalagmite δ18O records employed for hydroclimate reconstructions. We present ~12‐year‐long time series of biweekly cave drip water δ18O variations from three sites as well as a daily resolved local rainfall δ18O record from Gunung Mulu National Park in northern Borneo. Drip water δ18O variations closely match rainfall δ18O variations averaged over the preceding 3–18 months. We observe coherent interannual drip water δ18O variability of ~3‰ to 5‰ related to the El Niño–Southern Oscillation (ENSO), with sustained positive rainfall and drip water δ18O anomalies observed during the 2015/2016 El Niño. Evidence of nonlinear behavior at one of three drip water monitoring sites implies a time‐varying contribution from a longer‐term reservoir. Our results suggest that well‐replicated, high‐resolution stalagmite δ18O reconstructions from Mulu could characterize past ENSO‐related variability in regional hydroclimate.Plain Language SummaryCave stalagmites allow for the reconstruction of past regional rainfall variability over the last hundreds of thousands of years with robust age control. Such reconstructions rely on the fact that differences in the isotopic composition of rainwater set by regional rainfall patterns is preserved as the rainwater travels through cave bedrock to feed the cave drip waters forming stalagmites. Long‐term monitoring of rainwater and cave drip water isotopes ground truth the climate to stalagmite relationship across modern‐day changes in regional rainfall. Twelve years of monitoring data presented in this study identify individual El Niño–Southern Oscillation events in rainfall and cave drip water isotopic composition, providing a strong foundation for stalagmite‐based climate reconstructions from this site.Key PointsThree 12‐year‐long cave drip water δ18O time series capture El Niño and La Niña events in northern BorneoEstimates of karst residence times range from 3 to 18 months, with a secondary contribution from a longer‐term reservoir at one drip siteDrip water nonstationarity implies multiple stalagmites are required to reconstruct El Niño–Southern Oscillation variability over timePeer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/154266/1/grl60264-sup-0002-2019GL086363-SI.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/154266/2/grl60264_am.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/154266/3/grl60264.pd

    Radio observations of the planetary nebula around the OH/IR Star OH354.88-0.54 (V1018 Sco)

    Full text link
    We present radio observations of the unique, recently formed, planetary nebula (PN) associated with a very long-period OH/IR variable star V1018 Sco that is unequivocally still in its asymptoticgiant branch phase. Two regions within the optical nebula are clearly detected in nonthermal radio continuum emission, with radio spectral indices comparable to those seen in colliding-wind Wolf-Rayet binaries. We suggest that these represent shocked interactions between the hot, fast stellar wind and the cold nebular shell that represents the PN's slow wind moving away from the central star. This same interface produces both synchrotron radio continuum and the optical PN emission. The fast wind is neither spherical in geometry nor aligned withany obvious optical or radio axis. We also report the detection of transient H2O maser emission in this nebula.Comment: 11 pages, LaTeX (mn2e.cls), incl. 9 PostScript (ps or eps) figures and 2 tables. Accepted by MNRA

    Northern Borneo stalagmite records reveal West Pacific hydroclimate across MIS 5 and 6

    Get PDF
    Over the past decades, tropical stalagmite δ^(18)O records have provided valuable insight on glacial and interglacial hydrological variability and its relationship to a variety of natural climate forcings. The transition out of the penultimate glaciation (MIS 6) represents an important target for tropical hydroclimate reconstructions, yet relatively few such reconstructions resolve this transition. Particularly, comparisons between Termination 1 and 2 provide critical insight on the extent and influence of proposed climate mechanisms determined from paleorecords and model experiments spanning the recent deglaciation. Here we present a new compilation of western tropical Pacific hydrology spanning 0–160 ky BP, constructed from eleven different U/Th-dated stalagmite δ^(18)O records from Gunung Mulu National Park in northern Borneo. The reconstruction exhibits significant precessional power in phase with boreal fall insolation strength over the 0–160 ky BP period, identifying precessional insolation forcing as the dominant driver of hydroclimate variability in northern Borneo on orbital timescales. A comparison with a network of paleoclimate records from the circum-Pacific suggests the insolation sensitivity may arise from changes in the Walker circulation system. Distinct millennial-scale increases in stalagmite δ^(18)O, indicative of reduced regional convection, occur within glacial terminations and may reflect a response to shifts in inter-hemispheric temperature gradients. Our results imply that hydroclimate in this region is sensitive to external forcing, with a response dominated by large-scale temperature gradients
    corecore