Not Invisible: Asian Pacific Islander Juvenile Arrests in San Francisco County

This report is based on data that was originally collected by the San Francisco Juvenile Probation Department. The data reflect all juvenile arrests in the city and county of San Francisco that were referred to the Probation Department and are presented in two ways: 1) total number of arrests per year, and 2) total number of individual youths who were arrested during a given year. Many of the youths who were categorized in the race/ethnic field as "Other Asian" and "Other" can be classified into a specific race/ethnic group by examining the youth's last name. A database of common Asian Pacific Islander surnames and the race/ethnic group that coincides with that surname was developed for the purpose of this project

Not Invisible: Asian Pacific Islander Juvenile Arrests in Alameda County

This report is based on data that were originally collected by the Alameda County Probation Department. The data reflect all juvenile arrest referrals to probation (i.e., official court referral) in the county of Alameda from 1991-2000 and are presented in two ways: number of arrests which are reports of events, not unduplicated individuals, and number of unique youths which are reports of unique youths for the given year. Many of the youths who were categorized in the race/ethnic field as "Other Asian" and "Other" can be classified into a specific race/ethnic group by examining the youth's last name. A database of common Asian Pacific Islander surnames and the race/ethnic group that coincides with that surname was developed for the purpose of this project

Robust post-stall perching with a simple fixed-wing glider using LQR-Trees

Birds routinely execute post-stall maneuvers with a speed and precision far beyond the capabilities of our best aircraft control systems. One remarkable example is a bird exploiting post-stall pressure drag in order to rapidly decelerate to land on a perch. Stall is typically associated with a loss of control authority, and it is tempting to attribute this agility of birds to the intricate morphology of the wings and tail, to their precision sensing apparatus, or their ability to perform thrust vectoring. Here we ask whether an extremely simple fixed-wing glider (no propeller) with only a single actuator in the tail is capable of landing precisely on a perch from a large range of initial conditions. To answer this question, we focus on the design of the flight control system; building upon previous work which used linear feedback control design based on quadratic regulators (LQR), we develop nonlinear feedback control based on nonlinear model-predictive control and 'LQR-Trees'. Through simulation using a flat-plate model of the glider, we find that both nonlinear methods are capable of achieving an accurate bird-like perching maneuver from a large range of initial conditions; the 'LQR-Trees' algorithm is particularly useful due to its low computational burden at runtime and its inherent performance guarantees. With this in mind, we then implement the 'LQR-Trees' algorithm on real hardware and demonstrate a 95 percent perching success rate over 147 flights for a wide range of initial speeds. These results suggest that, at least in the absence of significant disturbances like wind gusts, complex wing morphology and sensing are not strictly required to achieve accurate and robust perching even in the post-stall flow regime.United States. Office of Naval Research. Multidisciplinary University Research Initiative (N00014-10-1-0951)National Science Foundation (U.S.) (Award IIS-0915148

Photodegradation disproportionately impacts biodegradation of semi‐labile DOM in streams

Exposure of dissolved organic matter (DOM) to sunlight can increase or decrease the fraction that is biodegradable (BDOM), but conceptual models fail to explain this dichotomy. We investigated the effect of sunlight exposure on BDOM, addressing three knowledge gaps: (1) how fractions of DOM overlap in their susceptibility to degradation by sunlight and microbes, (2) how the net effect of sunlight on BDOM changes with photon dose, and (3) how rates of DOM photodegradation and biodegradation compare in a stream. Stream waters were exposed to sunlight, and then fed through bioreactors designed to separate labile and semi‐labile pools within BDOM. The net effects of photodegradation on DOM biodegradability, while generally positive, represented the balance between photochemical production and removal of BDOM that was mediated by photon dose. By using sunlight exposure times representative of sunlight exposures in a headwater stream and bioreactors colonized with natural communities and scaled to whole‐stream dynamics, we were able to relate our laboratory findings to the stream. The impact of sunlight exposure on rates of DOM biodegradation in streams was calculated using rates of light absorption by chromophoric DOM, apparent quantum yields for photomineralization and photochemical alteration of BDOM, and mass transfer coefficients for labile and semi‐labile DOM. Rates of photochemical alteration of labile DOM were an order of magnitude lower than rates of biodegradation of labile DOM, but for semi‐labile DOM, these rates were similar, suggesting that sunlight plays a substantial role in the fate of semi‐labile DOM in streams.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/153758/1/lno11244.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/153758/2/lno11244_am.pd

Modelling Carbon Fluxes as an Aid to Understanding Perennial Ryegrass (Lolium perenne) Root Dynamics

Despite the importance of roots in determining plant performance, the factors controlling their development and longevity remain poorly understood. Grass morphology is based on repeating units called phytomers, with each capable of producing one leaf, one daughter tiller, and one or more roots. We developed a phytomer-based understanding of root birth, growth and senescence in Lolium perenne, using a modeling approach to explore seasonal effects on root turnover dynamics, and to explore cultivar differences in these processes. Similar to leaves, roots exhibit a clear progression from initiation, growing for approximately seven phyllochrons, with growth rates strongly influenced by environmental conditions. In spring, the phyllochron decreased over the experiment, while it increased in autumn. In spring, C availability exceeding maintenance respiratory requirements allowed root growth at each phytomer position, with a 70/30 split between maintenance and growth. Under C-deficient conditions in autumn, this split was approximately 80/20, with growth limited to younger phytomer positions, while older roots were more susceptible to starvation-induced senescence due to their high C requirements for maintenance respiration

A Coupled Geochemical and Biogeochemical Approach to Characterize the Bioreactivity of Dissolved Organic Matter From a Headwater Stream

The bioreactivity or susceptibility of dissolved organic matter (DOM) to microbial degradation in streams and rivers is of critical importance to global change studies, but a comprehensive understanding of DOM bioreactivity has been elusive due, in part, to the stunningly diverse assemblages of organic molecules within DOM. We approach this problem by employing a range of techniques to characterize DOM as it flows through biofilm reactors: dissolved organic carbon (DOC) concentrations, excitation emission matrix spectroscopy (EEMs), and ultrahigh resolution mass spectrometry. The EEMs and mass spectral data were analyzed using a combination of multivariate statistical approaches. We found that 45% of stream water DOC was biodegraded by microorganisms, including 31-45% of the humic DOC. This bioreactive DOM separated into two different groups: (1) H/C centered at 1.5 with O/C 0.1-0.5 or (2) low H/C of 0.5-1.0 spanning O/C 0.2-0.7 that were positively correlated (Spearman ranking) with chromophoric and fluorescent DOM (CDOM and FDOM, respectively). DOM that was more recalcitrant and resistant to microbial degradation aligned tightly in the center of the van Krevelen space (H/C 1.0-1.5, O/C 0.25-0.6) and negatively correlated (Spearman ranking) with CDOM and FDOM. These findings were supported further by principal component analysis and 2-D correlation analysis of the relative magnitudes of the mass spectral peaks assigned to molecular formulas. This study demonstrates that our approach of processing stream water through bioreactors followed by EEMs and FTICR-MS analyses, in combination with multivariate statistical analysis, allows for precise, robust characterization of compound bioreactivity and associated molecular level composition

A coupled geochemical and biogeochemical approach to characterize the bioreactivity of dissolved organic matter from a headwater stream

The bioreactivity or susceptibility of dissolved organic matter (DOM) to microbial degradation in streams and rivers is of critical importance to global change studies, but a comprehensive understanding of DOM bioreactivity has been elusive due, in part, to the stunningly diverse assemblages of organic molecules within DOM. We approach this problem by employing a range of techniques to characterize DOM as it flows through biofilm reactors: dissolved organic carbon (DOC) concentrations, excitation emission matrix spectroscopy (EEMs), and ultrahigh resolution mass spectrometry. The EEMs and mass spectral data were analyzed using a combination of multivariate statistical approaches. We found that 45% of stream water DOC was biodegraded by microorganisms, including 31–45% of the humic DOC. This bioreactive DOM separated into two different groups: (1) H/C centered at 1.5 with O/C 0.1–0.5 or (2) low H/C of 0.5–1.0 spanning O/C 0.2–0.7 that were positively correlated (Spearman ranking) with chromophoric and fluorescent DOM (CDOM and FDOM, respectively). DOM that was more recalcitrant and resistant to microbial degradation aligned tightly in the center of the van Krevelen space (H/C 1.0–1.5, O/C 0.25–0.6) and negatively correlated (Spearman ranking) with CDOM and FDOM. These findings were supported further by principal component analysis and 2‐D correlation analysis of the relative magnitudes of the mass spectral peaks assigned to molecular formulas. This study demonstrates that our approach of processing stream water through bioreactors followed by EEMs and FTICR‐MS analyses, in combination with multivariate statistical analysis, allows for precise, robust characterization of compound bioreactivity and associated molecular level composition. Key Points Humic DOM is susceptible to microbial degradation along with peptide‐like DOM Labile DOM can be distinguished from recalcitrant DOM in van Krevelen space EEMs and FTICR‐MS chemically characterize bioreactive and recalcitrant DOMPeer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/108612/1/jgrg20256.pd

Tropospheric Airborne Meteorological Data and Reporting (TAMDAR) Icing Sensor Performance during the 2003/2004 Alliance Icing Research Study (AIRS II)

NASA Langley Research Center and its research partners from the University of North Dakota (UND) and the National Center for Atmospheric Research (NCAR) participated in the AIRS II campaign from November 17 to December 17, 2003. AIRS II provided the opportunity to compare TAMDAR in situ in-flight icing condition assessments with in situ data from the UND Citation II aircraft's Rosemont system. TAMDAR is designed to provide a general warning of ice accretion and to report it directly into the Meteorological Data Communications and Reporting System (MDCRS). In addition to evaluating TAMDAR with microphysical data obtained by the Citation II, this study also compares these data to the NWS operational in-flight icing Current Icing Potential (CIP) graphic product and with the NASA Advanced Satellite Aviation-weather Products (ASAP) Icing Severity product. The CIP and ASAP graphics are also examined in this study to provide a context for the Citation II's sorties in AIRS II

Comprehensive Evidence-Based Assessment and Prioritization of Potential Antidiabetic Medicinal Plants: A Case Study from Canadian Eastern James Bay Cree Traditional Medicine

Canadian Aboriginals, like others globally, suffer from disproportionately high rates of diabetes. A comprehensive evidence-based approach was therefore developed to study potential antidiabetic medicinal plants stemming from Canadian Aboriginal Traditional Medicine to provide culturally adapted complementary and alternative treatment options. Key elements of pathophysiology of diabetes and of related contemporary drug therapy are presented to highlight relevant cellular and molecular targets for medicinal plants. Potential antidiabetic plants were identified using a novel ethnobotanical method based on a set of diabetes symptoms. The most promising species were screened for primary (glucose-lowering) and secondary (toxicity, drug interactions, complications) antidiabetic activity by using a comprehensive platform of in vitro cell-based and cell-free bioassays. The most active species were studied further for their mechanism of action and their active principles identified though bioassay-guided fractionation. Biological activity of key species was confirmed in animal models of diabetes. These in vitro and in vivo findings are the basis for evidence-based prioritization of antidiabetic plants. In parallel, plants were also prioritized by Cree Elders and healers according to their Traditional Medicine paradigm. This case study highlights the convergence of modern science and Traditional Medicine while providing a model that can be adapted to other Aboriginal realities worldwide

CXCR2 Signaling Protects Oligodendrocytes and Restricts Demyelination in a Mouse Model of Viral-Induced Demyelination

BACKGROUND: The functional role of ELR-positive CXC chemokines during viral-induced demyelination was assessed. Inoculation of the neuroattenuated JHM strain of mouse hepatitis virus (JHMV) into the CNS of susceptible mice results in an acute encephalomyelitis that evolves into a chronic demyelinating disease, modeling white matter pathology observed in the human demyelinating disease Multiple Sclerosis. METHODOLOGY/PRINCIPAL FINDINGS: JHMV infection induced the rapid and sustained expression of transcripts specific for the ELR+ chemokine ligands CXCL1 and CXCL2, as well as their binding receptor CXCR2, which was enriched within the spinal cord during chronic infection. Inhibiting CXCR2 signaling with neutralizing antiserum significantly (p<0.03) delayed clinical recovery. Moreover, CXCR2 neutralization was associated with an increase in the severity of demyelination that was independent of viral recrudescence or modulation of neuroinflammation. Rather, blocking CXCR2 was associated with increased numbers of apoptotic cells primarily within white matter tracts, suggesting that oligodendrocytes were affected. JHMV infection of enriched oligodendrocyte progenitor cell (OPC) cultures revealed that apoptosis was associated with elevated expression of cleaved caspase 3 and muted Bcl-2 expression. Inclusion of CXCL1 within JHMV infected cultures restricted caspase 3 cleavage and increased Bcl-2 expression that was associated with a significant (p<0.001) decrease in apoptosis. CXCR2 deficient oligodendrocytes were refractory to CXCL1 mediated protection from JHMV-induced apoptosis, readily activating caspase 3 and down regulating Bcl-2. CONCLUSION/SIGNIFICANCE: These findings highlight a previously unappreciated role for CXCR2 signaling in protecting oligodendrocyte lineage cells from apoptosis during inflammatory demyelination initiated by viral infection of the CNS