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Open Access Publications from the University of California

Scholarly Works (44 results)

  • Article
Lawrence Berkeley National Laboratory (2007)

The 4.5 MeV/nucleon heavy ion cocktail at the 88-Inch Cyclotron has been expanded by incorporating beams from solid material to fill in the linear energy transfer curve. This supercocktail is available by special request and is useful when only normal incidence between the beam and the device under test is possible or desirable.

    Cover page: "Super" Cocktails for Heavy Ion Testing
    • Article
    • Peer Reviewed
    Paroles gelées, Volume 19, Issue 2 (2001)
      Cover page: Homosexualité mon amour : Derrida and the Haunting of Sodom
      • Article
      • Peer Reviewed
      UC Irvine Previously Published Works (2010)
      Current standard methods result in significant discrepancies in carbon offset accounting compared to approaches based on representative community based subsamples, which provide more realistic assessments at reasonable cost. Perhaps more critically, neither of the currently approved methods incorporates uncertainties inherent in estimates of emission factors or non-renewable fuel usage (fNRB). Since emission factors and fNRB contribute 25% and 47%, respectively, to the overall uncertainty in offset estimates for Purépecha communities in Mexico, exclusion of this uncertainty is a critical omission. When the recommended uncertainty for default emission factors and the uncertainty associated with regional estimates of fNRB are included the lower 95% confidence intervals of both Clean Development Mechanism and Gold Standard methods exceed the total amount of carbon saved, which would result in zero marketable carbon savings if approaches recommended by the IPCC Good Practice Guidance and Uncertainty Management in National Greenhouse Gas Inventories, or Land use, Land-Use Change and Forestry (LULUCF) are to be followed. In contrast, for the same communities, methods using representative subsamples of emission factors and fuel consumption, combined with community-level fNRB estimates, result in significant carbon offsets with a lower 95% confidence interval of 2.3 tCO2e home − 1 year − 1. Given the misleading estimates, revision of the currently approved methodologies to provide robust estimates of carbon offsets is strongly recommended.
        Cover page: Improved stove programs need robust methods to estimate carbon offsets
        • Article
        • Peer Reviewed
        UC Santa Barbara Previously Published Works (2015)
        At radio wavelengths, scattering in the interstellar medium distorts the appearance of astronomical sources. Averaged over a scattering ensemble, the result is a blurred image of the source. However, Narayan & Goodman and Goodman & Narayan showed that for an incomplete average, scattering introduces refractive substructure in the image of a point source that is both persistent and wideband. We show that this substructure is quenched but not smoothed by an extended source. As a result, when the scatter-broadening is comparable to or exceeds the unscattered source size, the scattering can introduce spurious compact features into images. In addition, we derive efficient strategies to numerically compute realistic scattered images, and we present characteristic examples from simulations. Our results show that refractive substructure is an important consideration for ongoing missions at the highest angular resolutions, and we discuss specific implications for RadioAstron and the Event Horizon Telescope.
          Cover page: THEORY AND SIMULATIONS OF REFRACTIVE SUBSTRUCTURE IN RESOLVED SCATTER-BROADENED IMAGES
          • Article
          Technical Completion Reports (2009)

          We examined the potential for using riparian conifer trees (coast redwood and Douglasfir) to assess historical nutrient flux and salmon escapement (fish that escape capture by commercial fisheries in the open ocean and are able to return to their natal stream to spawn) to a pair of coastal California watersheds (Mill Creek and Waddell Creek). In each basin, periods of known annual salmon escapement were compared with data on tree-ring growth, nitrogen content [N] and stable nitrogen isotope ratios (δ15N). All tree-ring variables (lagged by +1 year) were positively correlated with Mill Creek salmon escapement, but relationships were inconsistent at Waddell Creek and highly dependent on the time lag applied (0 to 7 years). Annual ring δ15N was especially variable among individual trees growing at the same location with differences as high as 4.8‰ at spawning sites and 6.8‰ at salmon-free control sites. Linear regression-based models were used to reconstruct historical escapement for the periods 1946- 2002 and 1904-2003 in the Mill Creek and Waddell Creek watersheds, respectively. Tree-ring based reconstructions indicated considerable variation in historical escapement to both basins, and contemporary population declines which began in the 1960s (Mill Creek) and 1970s (Waddell Creek) and appeared to level off in the 1990s. Although δ15N was easily quantified in annual tree rings, stream, soil, and within-tree nitrogen dynamics greatly hinder the robust assessment of marine-derived versus autochthonous sources of nitrogen from riparian tree rings.

            Cover page: Evaluating the use of marine-derived nitrogen in riparian tree rings as an indicator of historical nutrient flux and salmon abundance
            • Article
            LBL Publications (2006)

            The BASE Light Ion Facility upgrades have been completed. All proton beams are now delivered to Cave 4A. New control software, a larger diameter beam window, and improved quality assurance measures have been added.

              Cover page: Berkeley Accelerator Space Effects (BASE) Light Ion Facility Upgrade
              • Article
              • Peer Reviewed
              UC Davis Previously Published Works (2016)
              Management of non-compressible torso hemorrhage (NCTH) remains a challenge despite continued advancements in trauma resuscitation. Resuscitative thoracotomy with aortic cross-clamping and recent advances in endovascular aortic occlusion, including resuscitative endovascular occlusion of the aorta, have finite durations of therapy due to the inherent physiologic stressors that accompany complete occlusion. Here, we attempt to illuminate the current state of aortic occlusion for trauma resuscitation including explanation of the deleterious consequences of complete occlusion, potential methods and limitations of existing technology to overcome these consequences, and a description of innovative methods to improve the resuscitation of NCTH. By explaining the complexity and potential deleterious effects of resuscitation augmented with aortic occlusion, our goal is to provide practitioners with a real-world perspective on current endovascular technology and to encourage the continued innovation required to overcome existing obstacles.
                Cover page: Emerging Endovascular Therapies for Non-Compressible Torso Hemorrhage
                • Article
                • Peer Reviewed
                UC Berkeley Previously Published Works (2023)
                MXenes are currently a research hotspot in the field of 2D materials, hinting to revolutionize material technology. Their layered architecture allows for molecular intercalation, defect engineering, and surface band gap functionalization, with applications as diverse as energy storage and drinking water desalination. Its structural and functional integrity has prompted the scientific community to investigate novel compositions in an effort to leverage electrochemical activity, mechanical robustness, flexibility and environmental stability. However, the current synthesis routes present a bottleneck in proposing MXenes as a sustainable material for the future. Therefore, by expanding the reach of synthetic chemistry towards efficient strategies for green production, we present the first comprehensive introspection of the use of green solvents and their impact on material properties during MXene synthesis. This review is an attempt to quantify the intriguing characteristics of MXene nanocomposites by embracing design tools like the ‘iceberg model’. To further evaluate the performance of MXenes fabricated using green strategies (such as eutectic etching) we have made an attempt to critically compare them with conventional MXenes by examining surface characteristics, electrochemical analysis, charge transfer mechanisms etc. Conclusively, we aim to instigate concern about the environmental impact of MXene synthesis and instil a multidisciplinary approach to tailor environmentally benign, scalable and efficient MXene derivatives for commercial energy applications. The review provides an immersive account linking UN sustainable development goals with the industrial outlook of green MXenes, it highlights their impact on climate change, potential to build technically advanced economies, low cost production and range of applications.
                  Cover page: Thinking green with 2-D and 3-D MXenes: Environment friendly synthesis and industrial scale applications and global impact
                  • Article
                  • Peer Reviewed
                  UC Davis Previously Published Works (2014)
                  Understanding factors influencing survival of Pacific salmonids (Oncorhynchus spp.) is essential to species conservation, because drivers of mortality can vary over multiple spatial and temporal scales. Although recent studies have evaluated the effects of climate, habitat quality, or resource management (e.g., hatchery operations) on salmonid recruitment and survival, a failure to look at multiple factors simultaneously leaves open questions about the relative importance of different factors. We analyzed the relationship between ten factors and survival (1980-2007) of four populations of salmonids with distinct life histories from two adjacent watersheds (Salmon and Scott rivers) in the Klamath River basin, California. The factors were ocean abundance, ocean harvest, hatchery releases, hatchery returns, Pacific Decadal Oscillation, North Pacific Gyre Oscillation, El Niño Southern Oscillation, snow depth, flow, and watershed disturbance. Permutation tests and linear mixed-effects models tested effects of factors on survival of each taxon. Potential factors affecting survival differed among taxa and between locations. Fall Chinook salmon O. tshawytscha survival trends appeared to be driven partially or entirely by hatchery practices. Trends in three taxa (Salmon River spring Chinook salmon, Scott River fall Chinook salmon; Salmon River summer steelhead trout O. mykiss) were also likely driven by factors subject to climatic forcing (ocean abundance, summer flow). Our findings underscore the importance of multiple factors in simultaneously driving population trends in widespread species such as anadromous salmonids. They also show that the suite of factors may differ among different taxa in the same location as well as among populations of the same taxa in different watersheds. In the Klamath basin, hatchery practices need to be reevaluated to protect wild salmonids.
                    Cover page: Potential Factors Affecting Survival Differ by Run-Timing and Location: Linear Mixed-Effects Models of Pacific Salmonids (Oncorhynchus spp.) in the Klamath River, California
                    • Article
                    • Peer Reviewed
                    UCLA Previously Published Works (2014)

                    Objective

                    The objective of the study was to describe our early experience with a comprehensive uterine fibroid center and report our results in women seeking a second opinion for management of symptomatic uterine leiomyoma.

                    Methods

                    We performed a HIPAA-complaint, IRB-approved retrospective study of women seeking second opinion for management of uterine fibroids at our multidisciplinary fibroid treatment center in a tertiary care facility from July 2008 to August 2011. After a review of patients' history, physical examination, and magnetic resonance imaging (MRI) findings, treatment options were discussed which included conservative management, uterine-preserving options, and hysterectomy. We performed Fisher's exact test for categorical variables between the cohort that did or did not undergo a uterine-preserving treatment. Differences were considered significant at p < 0.05.

                    Results

                    The mean age of the 205 patient study cohort was 43.8 years (SD 7.5). One hundred sixty-two (79.0%) patients had no prior therapy. Based on MRI, one or more fibroids were detected in 178/205 (86.8%), adenomyosis in 8/205 (3.9%), and a combination of fibroid and nonfibroid condition (i.e., adenomyosis, endometrial polyp) in 18/205 (8.8%). In those who desired to transition their care to our institution (n = 109), 85 patients underwent 90 interventions: 39 MRgFUS (magnetic resonance-guided high-intensity focused ultrasound surgery), 14 UAE (uterine artery embolization), 25 myomectomies, 8 hysterectomies, 3 polypectomies, and 1 endometrial ablation. Five patients had two procedures. Intramural and subserosal fibroids were most commonly treated with MRgFUS followed by myomectomy and then UAE; in contrast, pedunculated fibroids were frequently managed with myomectomy.

                    Conclusions

                    Multidisciplinary fibroid evaluation may facilitate the increase use of less invasive options over hysterectomy for symptomatic fibroid treatment.
                      Cover page: Women seeking second opinion for symptomatic uterine leiomyoma: role of comprehensive fibroid center
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