The Tenderloin Senior Outreach Project (TSOP) is presented as a case study of effective community-based organizing among the isolated elderly in one of America's large “grey ghettos.” Based on the theoretical underpinnings of social support theory and Freire's “education for critical consciousness,” the Project has attempted to address the interrelated problems of poor health, social isolation and powerlessness endemic among the elderly in Single Room Occupancy hotels. The Project's metamorphosis is traced from a university-sponsored community development effort to a community-controlled organization focused on broad social action objectives. The transference of leadership from health education facilitators to indigenous elderly leaders within the hotels is examined, as are some of the strategies employed in increasing Project visibility, preventing burn-out, and facilitating replication in other areas.
The intramolecular addition of β-ketoesters to unactivated alkynes under neutral conditions and at room temperature is described. The method employs triphenylphosphinegold(I) cation as a catalyst for the formation of <i>exo</i>-methylenecycloalkanes. Both monocyclic and bicyclic cyclopentanes and cyclohexanes can be formed in excellent yields and with good diastereoselectivity.
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
No abstract is provided for this article.
A fundamental problem in computer vision is that of inferring the intrinsic, 3D structure of the world from flat, 2D images of that world. Traditional methods for recovering scene properties such as shape, reflectance, or illumination rely on multiple observations of the same scene to overconstrain the problem. Recovering these same properties from a single image seems almost impossible in comparison -- there are an infinite number of shapes, paint, and lights that exactly reproduce a single image. However, certain explanations are more likely than others: surfaces tend to be smooth, paint tends to be uniform, and illumination tends to be natural. We therefore pose this problem as one of statistical inference, and define an optimization problem that searches for the *most likely* explanation of a single image. Our technique can be viewed as a superset of several classic computer vision problems (shape-from-shading, intrinsic images, color constancy, illumination estimation, etc) and outperforms all previous solutions to those constituent problems.
ZIMMERMAN, JACK E.; SHORTELL, STEPHEN M.; KNAUS, WILLIAM A.; ROUSSEAU, DENISE M.; WAGNER, DOUGLAS P.; GILLIES, ROBIN R.; DRAPER, ELIZABETH A.; DEVERS, KELLY Author Information
Reduced cell proliferation may mediate anticarcinogenic effects of caloric restriction (CR). Using heavy water ( 2 H 2 O) labeling, we investigated the cell proliferation response to CR in detail, including time course, effect of refeeding, and role of intermittent feeding with 5% CR. In the time-course study, 8-wk-old female C57BL/6J mice were placed on a 33% CR regimen (fed 3 times/wk) for varying durations. Compared with responses in controls fed ad libitum (AL), proliferation rates of keratinocytes, mammary epithelial cells, and T cells were markedly reduced within 2 wk of CR. In mice fed 95% ad libitum (C95, fed 3 times/wk), cell proliferation was also reduced in all tissues so that differences from 33% CR were only significant at 1 mo. In the refeeding study, mice were refed a C95 diet for varying durations after 1 mo of 33% CR. Cell proliferation rebounded to a suprabasal rate in all tissues after 2 wk of refeeding and then normalized after 2 mo, although the C95 group again exhibited lower cell proliferation than the AL group. The role of intermittent feeding was studied by comparing 33% CR and C95 animals (both fed intermittently) with animals fed isocalorically either daily or continuously by pellet dispenser. Intermittent feeding had no additive effect on 33% CR but reduced cell proliferation in all tissues at the 95% caloric intake level. In summary, the CR effect on cell proliferation is potent, rapid, and reversible in several tissues, and an intermittent feeding pattern reproduces much of the effect in the absence of substantial CR.
Summary: Stimulation of natural killer (NK) cells is regulated by a complex balance of inhibitory and stimulatory receptors expressed by NK cells. However, the interaction of stimulatory receptors and their ligands is poorly understood. One stimulatory receptor, NKG2D, is expressed by all NK cells, stimulated CD8 + T cells, γδ T cells and macrophages. Recently, progress has been made in defining cellular ligands for NKG2D. Four different families of ligands have been identified in mice and humans, all of which are distantly related to MHC class I molecules. Some of the ligands are upregulated in transformed and infected cells, provoking an attack by the innate and adaptive immune systems. It appears that these “induced‐self” ligands recognized by the NKG2D receptor may be a precedent for a new strategy of target cell recognition by the immune system. The authors wish to thank Dennis Wolan for preprints and discussions on the manuscript. AD is a Physician Postdoctoral Fellow of the Howard Hughes Medical Institute.
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Some reports of supernova (SN) discoveries turn out not to be true\ncore-collapse explosions. One such case was SN 2009ip, which was recognized to\nbe a luminous blue variable (LBV) eruption. This source had a massive hot\nprogenitor star identified in pre-explosion data, it had documented evidence of\npre-outburst variability, and it was subsequently discovered to have a 2nd\noutburst in 2010. This same source rebrightened again in 2012, and early\nspectra showed the same narrow-line profiles as before, suggesting another\nLBV-like eruption. We present new photometry and spectroscopy of SN 2009ip,\nindicating that it has transitioned into a true SN. The most striking discovery\nin these data is that unlike previous reports, the spectrum exhibited Balmer\nlines with very broad P-Cygni profiles characteristic of normal Type II\nsupernovae (SNe II), in addition to narrow emission lines seen in SNe IIn and\nLBVs. Emission components have FWHM 8000 km/s, while the P-Cygni absorption\ncomponent has blue wings extending to -13,000 km/s. These velocities are\ntypical of SNe II, but have never been associated with emission lines from a\nnonterminal LBV-like eruption. Initially, the peak absolute magnitude seemed\nfainter than that of normal SNe. However, after a brief period of fading, the\nsource quickly brightened again to M_R=-17.5 mag over a couple days. The broad\nlines mostly disappeared, and the spectrum began to resemble the early\noptically thick phases of SNe IIn. Two weeks later the source leveled off near\n-18 mag, after which broad emission lines again developed in the spectrum as\nthe source faded. We conclude that the 2012 outburst of SN 2009ip was the\nresult of a true core-collapse SN IIn that occured when the progenitor star was\nin an LBV-like outburst phase, and where the SN was initially faint and then\nrapidly brightened due to interaction with circumstellar material (abridged).\n
The primary objectives of the proposed research was the development of deterministic, physico-electrochemical models for predicting the accumulation of localized corrosion damage (pitting corrosion, stress corrosion cracking and corrosion fatigue) in the primary coolant circuits of the currently operating fleet of Light Water Reactors (LWRs) and the embedment of the models into the Grizzly code currently being developed at the Idaho National Laboratory as part of their program on nuclear power plant component aging. Localized corrosion in LWR (BWR and PWR) primary coolant circuits (PCC) is primarily an electrochemical phenomenon, augmented by mechanics and microstructure, the rate of which is determined by certain electrochemical properties, such as the electrochemical corrosion potential (ECP), solution conductivity, temperature, pH, flow rate, and the kinetics of the reduction of redox depolarizers (e.g. O<sub>2</sub>, H<sub>2</sub>O<sub>2</sub>, and H<sub>2</sub>) on the surfaces external to the crack, in addition to mechanical loading (stress intensity factor on the crack) and micro-structural/micro-chemical factors (grain size, precipitates, etc). Because the efficient control of environmentally-assisted cracking (EAC) damage accumulation requires the accurate control of these parameters, it is necessary to develop codes that can accurately predict ECP and crack growth rate (CGR) at any point in the primary coolant circuit (PCC) over wide ranges of temperature (25 <sup>o</sup>C to 320 <sup>o</sup>C), pH (6 – 8), ECP (-0.9 V<sub>she</sub> to 0.2 V<sub>she</sub>), solution conductivity, flow rate (1 – 6 m/s), and stress intensity factor (5 MPa.m<sup>1/2</sup> – 50 MPa.m<sup>1/2</sup>). Knowledge of these parameters, along with suitable damage prediction codes, would allow an operator to predict the accumulated damage in PCC as a function of the future operating history of the reactor (the “corrosion evolutionary path,” CEP). In performing this study, we have further developed our previous prediction codes in the form of BWR_MASTER and PWR_MASTER by upgrading all sub-models for calculating radiolytic species concentration, ECP, and crack growth rate (CGR) as a function of reactor operating variables (power, radiation density, temperature, location in the PCC, flow velocity, coolant pH and conductivity, and operating history). The codes have been used to predict the accumulation of IGSCC damage in Type 304 SS in the core shroud of a BWR over a fuel cycle and to estimate the damage at the same location during start-up, considering transients in reactor power, temperature, and conductivity (due to hide-out/hide-out return). The predicted damage is in good agreement with plant observation. Regarding PWRs, we have developed two new models for calculating CGR in mill-annealed, Alloy 600, by considerably upgrading the MPM (mixed potential model for estimating the ECP), the Coupled 2 Environment Fracture Model (CEFM) that were originally developed to predict ECP and CGR in sensitized stainless steels, to predict CGR in nickel-base alloys, as well as developing a micro- void pressurization model for also estimating CGR in MA Alloy 600. Both CGR models yield CGRs that are in excellent agreement with the experiment. We have also successfully developed crack initiation models for both stainless steels and mill-annealed, Alloy 600. That for stainless steels is based on a pit being the initiation site, whereas in that for mill-annealed, Alloy 600 postulates that initiation occurs at emergent grain boundaries that have been wedged open by internal oxidation. Experiments show that the crack initiation time (CIT) is highly distributed and is a seemingly, random quantity that exhibits trends with various system properties, such as surface stress, hardness, yield strength, etc. Although not identified in the SoW, we have developed a theoretical framework for describing the distributions in the CIT by assuming a normal distribution in the number of initiation sites concerning surface stress. It is well-known from experiments that CGRs are highly distributed quantities also, with almost all systems exhibiting log-normal distributions. In work outside of that proposed, we used the ANN and CEFM to confirm that a log-normal distribution in CGR is expected theoretically if the independent variables are normally distributed. This work essentially defines the accuracy that one might expect in the calculated CGR due to randomness in the independent variables. To provide fundamental, input data for the various models, we have made extensive measurement of the kinetic parameters (exchange current density and Tafel constants) for the oxygen electrode reaction (OER) and the hydrogen electrode reaction (OER) on stainless steels (Types 304 and 316) and nickel-base alloys (Alloys 600 and 690) in reactor coolant at temperatures to 300<sup> o</sup>C and as a function of pH, [O<sub>2</sub>], and [H<sub>2</sub>]. We have also optimized the Point Defect Model for passivity and passivity breakdown on measured electrochemical impedance spectroscopic (EIS) data for all alloys studied in
