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Open Access Publications from the University of California

Scholarly Works (29 results)

  • Article
  • Peer Reviewed
UC San Diego Previously Published Works (2009)
Video sensors with embedded compression offer significant energy savings in transmission but incur energy losses in the complexity of the encoder. Energy efficient video compression architectures for CMOS image sensors with focal-plane change detection are presented and analyzed. The compression architectures use pixel-level computational circuits to minimize energy usage by selectively processing only pixels which generate significant temporal intensity changes. Using the temporal intensity change detection to gate the operation of a differential DCT based encoder achieves nearly identical image quality to traditional systems (4dB decrease in PSNR) while reducing the amount of data that is processed by 67% and reducing overall power consumption reduction of 51%. These typical energy savings, resulting from the sparsity of motion activity in the visual scene, demonstrate the utility of focal-plane change triggered compression to surveillance vision systems.
    Cover page: Focal-Plane Change Triggered Video Compression for Low-Power Vision Sensor Systems
    • Article
    • Peer Reviewed
    UC San Diego Previously Published Works (2015)
    Purpose To evaluate long-term, longitudinal displacement of the optic nerve head (ONH) and anterior lamina cribrosa surfaces in glaucoma patients imaged with spectral-domain optical coherence tomography (SD OCT). Design Prospective study. Participants A total of 173 eyes of 108 subjects (88 with glaucoma and 20 normal subjects) followed for a mean of 5.3 years. Methods The optic disc was imaged with SD OCT at approximately 4-month intervals, and the ONH surface depth (ONHSD), anterior lamina cribrosa surface depth (ALCSD), and prelaminar tissue thickness (PTT) were measured. The reproducibility coefficients of ONHSD, ALCSD, and PTT were calculated from 2 baseline measurements of the glaucoma group. Change in ONHSD/ALCSD/PTT was confirmed when the differences between the first baseline and the latest 2 consecutive follow-up visits were greater than the corresponding reproducibility coefficient. Factors associated with ONHSD and ALCSD changes were identified with linear mixed modeling. Main Outcome Measures Proportion of eyes with ONHSD/ALCSD change. Results Within the glaucoma group, 23.9% (33 eyes) had confirmed ONHSD change (15.2% with posterior and 8.7% with anterior displacement) and 24.6% (34 eyes) had confirmed ALCSD change (12.3% with posterior and 12.3% with anterior displacement). Some 9.4% (13 eyes) showed a decrease in PTT, and 2.2% (3 eyes) showed an increase in PTT. The specificity for detection of ONHSD/ALCSD/PTT change was 91.4% (95% confidence interval [CI], 77.6-97.0), 82.9% (95% CI, 67.3-91.9), and 94.3% (95% CI, 81.4-98.4), respectively. There were no significant differences in the proportion of eyes with visual field progression or history of filtration surgery between the groups with anterior and posterior displacement of ONH/anterior laminar surfaces (P ≥ 0.678). For each millimeter of mercury increase in the average intraocular pressure (IOP) during follow-up, the ONH and anterior laminar surfaces displaced posteriorly by 1.6 μm and 2.0 μm, respectively. An older age was associated with a decrease in magnitude of posterior displacement of the ONH and anterior laminar surfaces (P ≤ 0.009). Conclusions The ONH and anterior laminar surfaces displaced not only posteriorly but also anteriorly (with reference to Bruch's membrane opening) in a significant portion of glaucoma patients. The magnitude of change was related to age and the averaged IOP during follow-up.
      Cover page: Optic Nerve Head Deformation in Glaucoma: A Prospective Analysis of Optic Nerve Head Surface and Lamina Cribrosa Surface Displacement
      • Article
      • Peer Reviewed
      UC Davis Previously Published Works (2007)

      Objective

      Human adenovirus Ad-36 causes adiposity in animal models and enhances differentiation and lipid accumulation in human and 3T3-L1 preadipocytes, which may, in part, explain the adipogenic effect of Ad-36. We determined the consequences of Ad-36 infection on leptin and glucose metabolism in fat cells.

      Design

      3T3-L1 preadipocytes were used to determine the effect of infection by human adenoviruses Ad-36, Ad-2, Ad-9 and Ad-37 on leptin secretion and lipid accumulation. Rat primary adipocytes were used to determine the effect of Ad-36 infection on leptin secretion and glucose uptake in vitro. Furthermore, the effect of Ad-36 on expressions of leptin and selected genes of de novo lipogenesis pathway of visceral adipose tissue were compared ex vivo, between Ad-36 infected and uninfected control rats.

      Results

      Ad-36 suppressed the expression of leptin mRNA in 3T3-L1 cells by approximately 58 and 52% on days 3 and 5 post-infection, respectively. Leptin release normalized to cellular lipid content was 51% lower (P<0.002) in the Ad-36 infected 3T3-L1 cells. Lipid accumulation was significantly greater and leptin secretion was lower for the 3T3-L1 cells infected with other human adenoviruses Ad-9, Ad-36, or Ad-37. Whereas, human adenovirus Ad-2 did not influence cellular lipid accumulation or the leptin release. In rat primary adipocytes, Ad-36 reduced leptin release by about 40% in presence of 0.48 (P<0.01) or 1.6 nM insulin (P<0.05) and increased glucose uptake by 93% (P<0.001) or 18% (P<0.05) in presence of 0 or 0.48 nM insulin, respectively. Next, the adipose tissue of Ad-36 infected rats showed two to fivefold lower leptin mRNA expression, and 1.6- to 21-fold greater expressions for acetyl Co-A carboxylase-1 and 1.2- to 6.3-fold greater expressions for fatty acid synthase, key genes of de novo lipogenesis, compared to the uninfected weight and adiposity matched controls.

      Conclusion

      The in vitro and ex vivo studies show that Ad-36 modulates adipocyte differentiation, leptin production and glucose metabolism. Whether such a modulation contributes to enhanced adipogenesis and consequent adiposity in Ad-36 infected animals or humans needs to be determined.
        Cover page: Adipogenic human adenovirus-36 reduces leptin expression and secretion and increases glucose uptake by fat cells
        • Article
        • Peer Reviewed
        UC San Francisco Previously Published Works (2014)
        © 2014 Morris et al.Background: It is increasingly recognized that the risk for HIV and hepatitis C (HCV) transmission among people who inject drugs (PWID), such as syringe sharing, occurs in the context of relationships between (at least) two people. Evid
          • Article
          • Peer Reviewed
          The Proceedings of the International Plant Nutrition Colloquium XVI (2009)

          Roles of mucilage in protection of root apices from Al toxicity are studied by the comparison of Al binding in different polysaccharides of mucilage and root Al uptake in solution with exogenous pectin and dextran as well as root growth and Al uptake with/without mucilage under mist culture. The results indicate root apices removed of mucilage have higher content of Al and lower root elongation rates. Size exclusion chromatography shows: two peaks of polysaccharides are overlapped by Al content and higher content of Al is found in the fraction of high molecular weight, Al binding enlarges the molecular weight of polysaccharides, thus indicated that Al is bound in polysaccharide especially in high molecular weight fraction. Exogenous pectin is more effectively reduced Al uptake in root apices than dextran and shows a dose dependent manner. These results indicated that polysaccharides with high molecular weight (e.g. pectin) might be more effective in immobilizing Al as well as reducing Al uptake in root apices.

            Cover page: The binding of Al in different polysaccharides alleviates Al toxicity to root apices
            • Article
            • Peer Reviewed
            UC San Francisco Previously Published Works (2014)
            Background: People who inject drugs (PWID) are at highest risk for hepatitis C virus (HCV) infection, yet many remain unaware of their infection status. New anti-HCV rapid testing has high potential to impact this. Methods. Young adult (<30 years) active P
              • Article
              • Peer Reviewed
              California Breast Cancer Research Program Funded Publications (1997)

              Markers in the 3' end of the vitamin D receptor gene have recently been associated with prostate cancer risk. To evaluate the adequacy of the commonly used BsmI restriction fragment length polymorphism as a marker of this locus, we genotyped 627 individuals from five ethnic groups for this marker, as well as for a polymorphic site in the 3' untranslated region of this gene. At the latter site, we identified 12 alleles, A13 to A24, of a poly(A) microsatellite. Allele size followed a bimodal distribution with distinct short (A13-A17) and long (A18-A24) allele populations. Poly(A) allele frequency differed by ethnicity, with the frequency of short alleles being highest in non-Hispanic whites (41%), intermediate in Hispanics and African-Americans (31 and 29%, respectively), and lowest in Japanese-Americans and Chinese (8 and 9%, respectively). In each of the ethnic groups, some degree of coupling was observed between BsmI B and short poly(A) alleles and between BsmI b and long poly(A) alleles. However, the strength of the linkage disequilibrium varied by ethnicity, with departures from complete disequilibrium producing disagreement between the BsmI and poly(A) genotypes. Genotypic disagreement was lowest in Japanese-Americans and non-Hispanic whites (6 and 7%, respectively), intermediate in Chinese and Hispanics (11 and 19%, respectively), and highest among African-Americans (37%), indicating that BsmI is not a good marker for the vitamin D receptor 3' untranslated region genotype in all populations. This finding may explain contradictory results from recent association studies using the BsmI marker.

                Cover page: Strength of linkage disequilibrium between two vitamin D receptor markers in five ethnic groups: implications for association studies.
                • Article
                • Peer Reviewed
                UC San Francisco Previously Published Works (2014)
                Low-grade systemic inflammation is often associated with metabolic syndrome, which plays a critical role in the development of the obesity-associated inflammatory diseases, including insulin resistance and atherosclerosis. Here, we investigate how Toll-lik
                  • Article
                  • Peer Reviewed
                  LBL Publications (2016)
                  As part of the Large Hadron Collider (LHC) Luminosity upgrade program, the U.S.-LHC Accelerator Research Program collaboration and CERN are working together to design and build a 150-mm aperture Nb3Sn quadrupole for the LHC interaction regions. A first series of 1.5-m-long coils was fabricated and assembled in a first short model. A detailed visual inspection of the coils was carried out to investigate cable dimensional changes during heat treatment and the position of the windings in the coil straight section and in the end region. The analyses allow identifying a set of design changes which, combined with a fine tune of the cable geometry and a field quality optimization, were implemented in a new second-generation coil design. In this paper, we review the main characteristics of the first generation coils, describe the modification in coil layout and discuss their impact on parts design and magnet analysis.
                    Cover page: Second-Generation Coil Design of the Nb3Sn low- $\beta$ Quadrupole for the High Luminosity LHC
                    • Article
                    • Peer Reviewed
                    UCLA Previously Published Works (2004)

                    The 1999 Chi-Chi, Taiwan, earthquake provides case histories of ground failure and non-ground failure that are valuable to the ongoing development of liquefaction susceptibility, triggering and surface manifestation models because the data occupy sparsely populated parameter spaces (i.e. high cyclic stress ratio and high fines content with low to moderate soil plasticity). In this paper, we document results from several large site investigation programs conducted in Nantou, Wufeng and Yuanlin, Taiwan. The seismic performance of the investigated sites include non-ground failure building and free-field sites, building sites with partial foundation hearing failures, free-field lateral spread sites, and free-field level ground sites with sediment boils. Field and laboratory investigation protocols for the sites are described, including cone penetration testing (some with pore pressure and shear wave velocity measurements) and rotary wash borings with standard penetration testing (including energy measurements). Implications of the SPT energy measurements with respect to established guidelines for the estimation of SPT energy ratio (including short rod corrections) are presented. Finally, data for three example sites are shown that illustrate potential applications of the data set, and which also demonstrate a condition where existing liquefaction analysis procedures fail to predict the observed field performance. (C) 2004 Elsevier Ltd. All rights reserved.

                      Cover page: Documentation of soil conditions at liquefaction and non-liquefaction sites from 1999 Chi-Chi (Taiwan) earthquake
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