Remedial Stability Analysis of Unstable Eastern Approach Embankment, Bluegrass Parkway Bridges over Chaplin River

In a meeting held on March 7, 1973, the Division of Research was requested to perform a supplementary slope stability analysis of the unstable, eastern approach embankment and foundation located at the crossing of the Bluegrass Parkway over Chaplin River and extending between Stations 2317+14 and 2321+00. Previously (see referenced report), two remedial schemes had been considered for increasing the stability of the unstable soil mass to an acceptable level. Those included: 1) loading the toe area of the existing, eastern approach slope with a berm, including a sloping berm, and 2) unloading the upper portion of the eastern slope by excavation, that is, decreasing the original approach slope (1.5 horizontal to 1 vertical), which would require an extension of the bridges, construction of piers at the present locations of the abutments and a relocation of the abutments. In the report cited, consideration was given primarily to using a berm to stabilize the eastern approach slope. Normally, that method of increasing the stability of an unstable embankment is the most economical. However, loading the toe area of the existing slope with a berm was considered undesirable in the meeting of March 7, 1973, because a berm would extend into the Chaplin River channel and alter channel hydraulics by constricting the channel area. Furthermore, there was a question of whether the berm materials could withstand the high velocities of Chaplin River. Consequently, an in-depth stability analysis was performed which involved excavation of the approach embankment and a relocation of the abutments

Nitrogen recycling in coastal waters of southeastern U.S. during summer 1986

Summer-time pelagic nitrogen recycling using an 15NH4+ tracer technique was studied for important biological pathways, sinks, and residence times in the microbial food web of coastal Georgia, U.S.A. Results showed that estimated rates of NH4+ regeneration by a variety of microheterotrophs and microzooplankton balanced rates of NH4+ assimilation by the microbial community, i.e., phytoplankton, bacteria and other microheterotrophs, in surface waters. In bottom water below the 1% light level, NH4+ regeneration exceeded community NH4+ assimilation by 3.5 times. However, over a period of 2 weeks, high NH4+ concentrations rarely occurred in bottom waters, and this was attributed to rapid mixing of the water column by winds and tides. Estimated mixing times from time-dependent numerical models were on the order of NH4+ turnover times of 5 to 10 hours. Overall, rates of community NH4+ assimilation exceeded rate estimates of phytoplankton N demand by 1.8 to 2.7 fold, which were made from rates of 14CO2 incorporation into proteins. In bottom samples where phytoplankton were light limited, rates of NH4+ assimilation exceeded the phytoplankton N demand by 3.6 to 11.1 fold. Calculations concerning the role of dissolved organic nitrogen in N cycling suggest that only 10% is recycled to NH4+ daily. This N could support 12 to 29% of the estimated phytoplankton N demand. Residence times of particulate nitrogen pools, based on rates of NH4+ regeneration, were on the order of 3–10 days. During summer-time hydrographic conditions and despite other losses, particulate nitrogen could recycle as often as 100 times before autumn removal processes occur off southeastern U.S

Prevention of Renal ApoB Retention is Protective Against Diabetic Nephropathy: Role of TGF-β Inhibition

Animal studies demonstrate that hyperlipidemia and renal lipid accumulation contribute to the pathogenesis of diabetic nephropathy (DN). We previously demonstrated that renal lipoproteins colocalize with biglycan, a renal proteoglycan. The purpose of this study was to determine whether prevention of renal lipid (apoB) accumulation attenuates DN. Biglycan-deficient and biglycan wild-type Ldlr−/− mice were made diabetic via streptozotocin and fed a high cholesterol diet. As biglycan deficiency is associated with elevated transforming growth factor-β (TGF-β), in some experiments mice were injected with either the TGF-β-neutralizing antibody, 1D11, or with 13C4, an irrelevant control antibody. Biglycan deficiency had no significant effect on renal apoB accumulation, but led to modest attenuation of DN with ∼30% reduction in albuminuria; however, biglycan deficiency caused a striking elevation in TGF-β. Use of 1D11 led to sustained suppression of TGF-β for approximately 8 weeks at a time. The 1D11 treatment caused decreased renal apoB accumulation, decreased albuminuria, decreased renal hypertrophy, and improved survival, compared with the 13C4 treatment. Thus, prevention of renal apoB accumulation is protective against development of DN. Furthermore, this study demonstrates that prevention of renal apoB accumulation is a mechanism by which TGF-β inhibition is nephroprotective

The isolation and culture of endothelial colony forming cells from human and rat lungs

Blood vessels are crucial for the normal development, lifelong repair and homeostasis of tissues. Recently, vascular progenitor cell–driven 'postnatal vasculogenesis' has been suggested as an important mechanism that contributes to new blood vessel formation and organ repair. Among several described progenitor cell types that contribute to blood vessel formation, endothelial colony-forming cells (ECFCs) have received widespread attention as lineage-specific 'true' vascular progenitors. Here we describe a protocol for the isolation of pulmonary microvascular ECFCs from human and rat lung tissue. Our technique takes advantage of an earlier protocol for the isolation of circulating ECFCs from the mononuclear cellular fraction of peripheral blood. We adapted the earlier protocol to isolate resident ECFCs from the distal lung tissue. After enzymatic dispersion of rat or human lung samples into a cellular suspension, CD31-expressing cells are positively selected using magnetic-activated cell sorting and plated in endothelial-specific growth conditions. The colonies arising after 1–2 weeks in culture are carefully separated and expanded to yield pure ECFC cultures after a further 2–3 weeks. The resulting cells demonstrate the defining characteristics of ECFCs such as (i) 'cobblestone' morphology of cultured cell monolayers; (ii) acetylated low-density lipoprotein uptake and Ulex europaeus lectin binding; (iii) tube-like network formation in Matrigel; (iv) expression of endothelial cell–specific surface markers and the absence of hematopoietic or myeloid surface antigens; (v) self-renewal potential displayed by the most proliferative cells; and (vi) contribution to de novo vessel formation in an in vivo mouse implant model. Assuming typical initial cell adhesion and proliferation rates, the entire procedure can be completed within 4 weeks. Isolation and culture of lung vascular ECFCs will allow assessment of the functional state of these cells in experimental and human lung diseases, providing newer insights into their pathophysiological mechanisms

Dynamics and Origin of the 2:1 Orbital Resonances of the GJ 876 Planets

(Abridged) A dynamical fit has placed the two planets about the star GJ 876 in coplanar orbits deep in 3 resonances at the 2:1 mean-motion commensurability with small libration amplitudes. The libration of both lowest order mean-motion resonance variables, theta_1 and theta_2, and the secular resonance variable, theta_3, about 0 deg. differs from the familiar geometry of the Io-Europa pair, where theta_2 and theta_3 librate about 180 deg. By considering a condition for stable simultaneous librations of theta_1 and theta_2, we show that the GJ 876 geometry results because of the large orbital eccentricities e_i, whereas the very small e_i in the Io-Europa system lead to the latter's geometry. Surprisingly, the GJ 876 resonance configuration remains stable for e_1 up to 0.86 and for amplitude of libration of theta_1 approaching 45 deg. with the current e_i. We find that inward migration of the outer planet of the GJ 876 system results in certain capture into the observed resonances if initially e_1 <0.06 and e_2<0.03 and the migration rate |(da_2/dt)/a_2| < 0.03(a_2/AU)^{-3/2} yr^{-1}. The bound on the migration rate is easily satisfied by migration due to planet-nebula interaction. If there is no eccentricity damping, eccentricity growth is rapid with continued migration within the resonance, with e_i exceeding the observed values after a further reduction in the semi-major axes a_i of only 7%. With eccentricity damping (de_i/dt)/e_i = -K|(da_i/dt)/a_i|, the e_i reach equilibrium values that remain constant for arbitrarily long migration within the resonances. The equilibrium e_i are close to the observed e_i for K=100 (K=10) if there is migration and damping of the outer planet only (of both planets). It is as yet unclear that planet-nebula interaction can produce the large value of K required to obtain the observed eccentricities.Comment: 23 pages, including 8 figures; uses AASTeX v5.0; minor additions; accepted for publication in Ap

Effect of Method of Delivering Nicarbazin to Mallards on Plasma 4,4′-Dinitrocarbanilide Levels and Reproduction

Nicarbazin (NCZ), a coccidiostat used in the poultry industry, has been developed as a contraceptive for resident Canada geese. We tested the efficacy of NCZ as a contraceptive using mallards (Anas platyrhynchos) as a model for Canada geese. Nicarbazin-treated corn was fed ad libitum for 14 d at 0, 750, 1,000, or 1,500 ppm. Plasma and egg levels of 4,4′-dinitrocarbanilide (DNC), the active anticoccidial component of NCZ, differed among treatment groups in a dose-response relationship, but plasma levels did not differ between sexes. Nicarbazin caused a decrease in egg weight, but there was no effect of NCZ on the numbers of eggs laid per female per day. Nicarbazin did not significantly impact bird health. An additional trial tested the effect of the method of NCZ delivery on plasma DNC levels. Mallards were given NCZ daily for 12 d either by gavage with a corn oil suspension, gavage with a water suspension, peroral administration of a capsule, or feeding 500 mg of NCZ/kg of pelleted feed ad libitum. The method of delivery significantly affected plasma DNC levels, with the highest levels in the corn oil suspension group and the lowest levels in the pelleted feed group. This is likely due to decreased availability of NCZ in a pellet compared with gavage with a suspension or capsule. Mallards receiving 34.2 mg of NCZ/kg of BW when fed cracked corn coated with NCZ daily for 14 d had higher plasma DNC levels than those obtained by liquid gavage, capsule, or pelleted NCZ feed. For maximum effect in the field, NCZ should be coated onto corn. A higher concentration of NCZ is needed in pelleted feed to obtain comparable plasma DNC levels to allow for the decreased absorption of DNC

Independent Evaluation of Phase 1 of the Affordable Medicines Facility - malaria (AMFm), Multi-Country Independent Evaluation Final Report

The success of malaria control efforts depends on a high level of coverage in the use of effective antimalarials such as artemisinin-based combination therapies (ACTs). Although these anti-malarials have been procured in large amounts by countries, evidence suggests that ACT use still remains far below target levels. In response to this issue, the Affordable Medicines Facility – malaria (AMFm) hosted by the Global Fund to Fight AIDS, Tuberculosis and Malaria (Global Fund) was set up. AMFm comprises three key elements: (i) price reductions through negotiations with ACT manufacturers; (ii) a buyer subsidy through a ‘co-payment’ for ACTs at the top of the global supply chain; and (iii) supporting interventions to promote appropriate use of ACTs. Examples of these supporting interventions include training providers and outreach to communities to promote ACT use. All ACTs subsidized through AMFm bear a green leaf logo on their packaging. The four main objectives of AMFm are to: (i) increase ACT affordability; (ii) increase ACT availability; (iii) increase ACT use, including among vulnerable groups; and (iv) “crowd out” oral artemisinin monotherapies, chloroquine and sulfadoxine-pyrimethamine (SP) by increasing the market share for ACTs

Characterizing Multi-planet Systems with Classical Secular Theory

Classical secular theory can be a powerful tool to describe the qualitative character of multi-planet systems and offer insight into their histories. The eigenmodes of the secular behavior, rather than current orbital elements, can help identify tidal effects, early planet-planet scattering, and dynamical coupling among the planets, for systems in which mean-motion resonances do not play a role. Although tidal damping can result in aligned major axes after all but one eigenmode have damped away, such alignment may simply be fortuitous. An example of this is 55 Cancri (orbital solution of Fischer et al., 2008) where multiple eigenmodes remain undamped. Various solutions for 55 Cancri are compared, showing differing dynamical groupings, with implications for the coupling of eccentricities and for the partitioning of damping among the planets. Solutions for orbits that include expectations of past tidal evolution with observational data, must take into account which eigenmodes should be damped, rather than expecting particular eccentricities to be near zero. Classical secular theory is only accurate for low eccentricity values, but comparison with other results suggests that it can yield useful qualitative descriptions of behavior even for moderately large eccentricity values, and may have advantages for revealing underlying physical processes and, as large numbers of new systems are discovered, for triage to identify where more comprehensive dynamical studies should have priority.Comment: Published in Celestial Mechanics and Dynamical Astronomy, 25 pages, 10 figure

Variability in coastal zone color scanner (CZCS) Chlorophyll imagery of ocean margin waters off the US East Coast.

Abstract The purpose of our study was to use the 7.5-year coastal zone color scanner (CZCS) image time series (Oct. 1978 to July, 1986 to study general patterns in near-surface phytoplankton chlorophyll concentrations in ocean margin waters off the US East Coast. We defined 21 relatively large study areas (&gt;100 km 2 ) within the MAB and SAB to set boundaries for averaging and subsequent analyses. Our objective was to partition the observed CZCS-derived chlorophyll concentration (CSAT, mg m À3 ) variability of these 21 study areas within three general categories based on time scale: daily (i.e. day-week), seasonal and interannual. An additional objective was to determine relations between the temporal patterns in the 21 study areas. All available CZCS imagery (more than 3500 scenes of Level 1 imagery, i.e. top-ofthe-atmosphere radiance in satellite swath coordinates) covering some or all of our area of interest (northwest Atlantic off the US East Coast) were obtained at full resolution, processed to Level 2 (waterleaving radiance, chlorophyll concentration and other derived products in satellite swath coordinates) and mapped to two different study regions located off the southeast and northeast coasts of the US. Satellitederived estimates of near-surface chlorophyll concentrations (CSAT) were extracted on a pixel-by-pixel basis from each of the 21 study areas (chosen based on oceanographic criteria) from each of the daily composite CSAT images. For each image and when satellite coverage permitted, CSAT values were averaged to yield a time series of daily mean values for each of the 21 study areas. We used three basic approaches to quantify temporal and spatial patterns in the 21 time series: (1) multiple linear correlation, (2) structure functions (semi-variance calculations) and (3) empirical orthogonal functions (EOF). Our results show: (1) a simple annual CSAT cycle common to all ocean margin waters along the entire US East Coast, consisting of a broad peak in CSAT concentration during winter and minimum concentrations during the summer